Permeable wall encapsulation mold

Abstract

A mold (100, 400) for encapsulating an electrical component (110). The mold (100, 400) includes an encapsulation chamber (120, 420) and an air inlet (150). The encapsulation chamber (120, 420) is defined by a housing (130, 430), an open top (436), and a solid bottom (438). The housing (130, 430) includes a solid outer wall (132, 432), a permeable inner wall (134), and an air chamber (140, 472) between the solid outer wall (132, 432) and the inner wall (134, 434). The air inlet (150) is configured to introduce gas into the air chamber (140, 472). The size and shape of the encapsulation chamber (120, 420) are set to receive the electrical component (110), while leaving a gap for introducing a sealant (200) around the electrical component (110). The sealant (200) can be silicone rubber. To remove the encapsulated electrical component (110), pressurized air can be introduced through the air inlet (150) into the air chamber (140, 472), passing through the permeable inner wall (134), thereby separating the outer surface of the sealant (200) from the housing (130, 430) and allowing the composite casting to be removed from the mold (100, 400).

Description

BACKGROUND OF THE INVENTION

[0001] Molding is a process of manufacturing an object (e.g., casting) by shaping a liquid or flexible material using a rigid frame called a mold, a pattern, or a setting. The mold can have a hollow interior volume that is filled with a liquid or flexible material such as rubber, plastic, glass, metal, etc. The material hardens or solidifies inside the mold, forming a shape that matches the interior volume of the mold. The mold can be created using a pattern or a model of the final desired product. A common molding process is casting molding, which uses gravity to introduce (e.g., pour) the liquid or flexible material into the hollow interior volume of the mold. A release agent can be applied to the hollow interior volume of the mold to more easily remove the hardened (e.g., solidified) casting from the mold. A rigid object can be inserted into the mold before or during the molding process so that the liquid or flexible material encapsulates the rigid object before cooling to form a final composite casting.

[0002] Silicone is a high molecular weight organosilicon compound. Silicone rubber is an elastomer (rubber-like material) composed of silicone resin. Throughout this disclosure, the term silicone will refer to the elastomeric form (e.g., silicone rubber). Silicone can be used in waterproof and heat-resistant components of electrical systems, such as voltage line insulators, vacuum interrupters, etc. For example, a vacuum interrupter can be encapsulated within an outer silicone layer for additional protection. Due to its flexible properties above its melting temperature (about 300 °C) and its relatively low curing rate, silicone is an ideal material for casting molding. Similarly, silicone can be cast at room temperature using a two-part addition curing process. However, silicone casting presents challenges during removal (e.g., ejection) of the casting from the mold.

[0003] For many elastic materials such as silicone rubber, it is difficult to eject a straight-walled, seamless high-silicone casting from a casting mold, and these elastic materials can generate significant friction with the inner surface of the mold. Due to the adhesion force between the outer surface of the silicone casting and the inner surface of the mold, significant force is required to remove the silicone casting from a common mold. Typically, a taper is used to facilitate ejection of the silicone casting, but in some cases, the tapered final product is not suitable for electrical applications. Alternatively, a flip mold process can be used, but in some cases, the seam parting line (e.g., flash) of the flip mold also renders the casting unusable in electrical applications. Any protrusion of material on the outer surface of an insulated electrical component, such as excess material along the parting line, will result in an undesirable gap between the insulated electrical component and an adjacent solid insulation layer. During operation of the electrical component, these gaps can cause dangerous high-voltage breakdowns between the solid insulation layers.

[0004] For example, a vacuum interrupter assembled into a preformed cylindrical straight-wall rigid housing (e.g., a cover) should not have a parting line because such a line would act as a failure path, and it should not have a tapered profile because a tapered profile would create an air gap that could cause dielectric breakdown in the main circuit under certain conditions.

[0005] This document describes a novel solution to at least some of the above problems. Summary of the Invention

[0006] In one embodiment, a mold for encapsulating an electrical component includes an encapsulation chamber and an air inlet. For example, in one embodiment, the encapsulation chamber is defined by a housing, an open top, and a solid bottom. Optionally, the bottom can be removable. The housing includes a solid outer wall, a permeable inner wall, and an air chamber between the solid outer wall and the inner wall. Optionally, each of the solid outer wall, the permeable inner wall, and the air chamber can be cylindrical. The air inlet is configured to introduce gas into the air chamber. The size and shape of the encapsulation chamber can be set to receive the electrical component while leaving a gap for introducing a sealant around the electrical component. Optionally, the sealant can be silicone rubber. Optionally, the gap can be from about 2 mm to about 5 mm.

[0007] For example, in one embodiment, the solid bottom includes at least one ring positioned between the solid outer wall and the permeable inner wall to maintain the gap that forms the air chamber between the solid outer wall and the permeable inner wall. Optionally, the open top includes a flat disk having a central opening, and the flat disk includes at least one second ring positioned between the solid outer wall and the permeable inner wall to further maintain the gap that forms the air chamber between the solid outer wall and the permeable inner wall.

[0008] For example, in another embodiment, the air chamber includes a plurality of inflatable chambers positioned between the solid outer wall and the permeable inner wall. Optionally, the air inlet can include a plurality of orifices, each orifice leading to one of the inflatable chambers. Optionally, the housing can include a plurality of inflatable chamber sidewall members that extend from the solid outer wall to the permeable inner wall and form the inflatable chambers.

[0009] In an alternative embodiment, a casting molding process for encapsulating an electrical component includes providing a mold, positioning the electrical component within the mold, introducing a sealant into the mold, curing the sealant around at least a portion of the electrical component within the mold to form a composite casting, separating the contact surface of the sealant from the mold, and ejecting the composite casting from the mold. Optionally, the electrical component can be a vacuum interrupter. Optionally, the sealant can be silicone rubber. The step of curing the sealant can include forming a composite casting of silicone rubber with a thickness of from about 2 mm to about 5 mm.

[0010] For example, in one embodiment, the mold includes an encapsulation chamber defined by a housing, an open top, a bottom, and an air inlet. The housing includes a solid outer wall, a permeable inner wall, and an air chamber between the solid outer wall and the inner wall. The air inlet is configured to introduce gas into the air chamber. During the step of introducing the sealant into the mold, the sealant is introduced between the electrical component and the permeable inner wall. During the step of separating the contact surface of the sealant from the mold, a pressurized gas is introduced into the air chamber to pass through the permeable inner wall.

[0011] For example, in another embodiment, the bottom of the mold is openable and closable, the step of enclosing the bottom end of the mold is before the step of introducing the sealant, the step of opening the bottom of the mold is before the step of introducing the pressurized gas into the air chamber, and the step of ejecting the combined casting includes pressing the combined casting through the open top from the bottom after opening the bottom.

[0012] For example, in another embodiment, the electrical component includes a top, a bottom, a cylindrical wall, a first post, and a second post. Optionally, the first post may extend from the top and be positioned within the open top of the mold. Optionally, the second post may extend from the bottom and be positioned within the bottom end of the mold. Optionally, the steps of introducing and curing the sealant may at least partially encapsulate the electrical component in the sealant, wherein the top of the electrical component remains exposed, the bottom of the electrical component remains exposed, or both the top and the bottom of the electrical component remain exposed.

[0013] For example, in another embodiment, the air chamber includes a plurality of inflatable chambers positioned between the solid outer wall and the permeable inner wall. Optionally, the air inlet may include a plurality of orifices, each orifice leading to one of the inflatable chambers. Optionally, the step of introducing the pressurized gas into the air chamber may include substantially equalizing the pressure in the air chamber by introducing the pressurized gas into each of the inflatable chambers.

[0014] In another alternative embodiment, a mold for encapsulating a workpiece includes an encapsulation chamber defined by a housing, an open top, and a solid bottom. For example, in one embodiment, the housing includes a solid outer wall, a permeable inner wall, and an air chamber between the solid outer wall and the inner wall. Optionally, the air chamber may include a plurality of inflatable chambers positioned between the solid outer wall and the permeable inner wall. Optionally, the solid outer wall may further include a plurality of air inlets, each air inlet leading to one of the inflatable chambers. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a cross-sectional view of an exemplary mold for encapsulating an electrical component using a permeable inner wall during a molding process.

[0016] Figure 2 is during the encapsulation process Figure 1 of the mold.

[0017] Figure 3 during the ejection process Figure 1 Cross-sectional view of the mold in

[0018] Figure 4 Isometric view of an exemplary mold for encapsulating an exemplary vacuum interrupter using a silicone sealant.

[0019] Figure 5 Is Figure 4 Exploded view of the mold in

[0020] Figure 6 Is Figure 4 Cross-sectional view of the mold in

[0021] Figure 7 Is related to Figure 6 Cross-sectional view of another exemplary mold similar to the mold of

[0022] Figure 8A Is Figure 6 Isometric cross-sectional view of the outer wall of the mold housing of

[0023] Figure 8B Is Figure 7 Isometric cross-sectional view of the outer wall of the mold housing of

[0024] Figure 9 Cross-sectional view of a mold having an exemplary encapsulated vacuum interrupter therein.

[0025] Figure 10 Is a flowchart showing an exemplary method for manufacturing a composite casting according to an embodiment. Detailed Description

[0026] Terms related to the present disclosure are provided at the end of this detailed description section. The drawings are not drawn to scale.

[0027] Figure 1 Cross-sectional view of an exemplary mold 100 for encapsulating a workpiece such as an electrical component 110. The mold 100 employs a permeable inner wall 134 during the molding process. The mold 100 may include an encapsulation chamber 120 for receiving the electrical component 110, and an air inlet 150 providing a path. Air from outside the mold 100 can be forced into the mold 100 through this path.

[0028] The encapsulation chamber 120 may be defined by the internal volume of the outer shell 130. The outer shell 130 may include an outer wall 132, an inner wall 134, a top wall 136, and a bottom wall 138. The gas chamber 140 may be defined by the volume between the outer wall 132 and the inner wall 134, optionally from the top wall 136 to the bottom wall 138 or any point between the top and bottom walls. Optionally, the top wall 136 and / or the bottom wall 138 may be removable, and the inner wall 134 may be separated from the outer wall 132. Alternatively, the outer wall 132, the inner wall 134, the top wall 136, and the bottom wall 138 may be integral.

[0029] The top wall 136 may include an upper opening 142, and the bottom wall 138 may include a lower opening 144 (see Figure 3 ). A removable plate 146 may be positioned within the lower opening 144. For example, the encapsulation chamber 120 may be defined as the volume within the inner wall 134 from the upper opening 142 to the plate 146 that fills the lower opening 144.

[0030] The outer wall 132, the top wall 136, and the bottom wall 138 may be solid in that they have a porosity value (i.e., the measure of pores within a solid body) small enough to prevent gas from passing through the outer wall 132, the top wall 136, and the bottom wall 138 from the gas chamber 140 to the exterior of the outer shell 130, as will be described in more detail below. (Note: When used in this document to refer to a wall, the term "solid" does not mean that the wall must be completely solid. Instead, it means that the inner or outer surface of the wall must be substantially airtight as described above.) The outer wall 132 may also include an orifice 148 that is configured to receive an air inlet 150 and serve as a conduit for gas to enter the gas chamber 140. The inner wall 134 may be permeable and have a porosity value large enough to allow gas to pass through the inner wall 134 from the gas chamber 140 to the interior of the encapsulation chamber 120, but not so porous as to allow encapsulating material to pass through the inner wall 134, as will be described in more detail below. For example, the inner wall 134 may be made of stainless steel, bronze, aluminum, or any material with a suitable controlled porosity. The air inlet 150 may be configured to introduce gas into the gas chamber 140. The gas may be a pressurized gas, as will be described in more detail below.

[0031] The size of the encapsulation chamber 120 may be set to substantially conform to the size and shape of the electrical component 110 or other workpiece, while leaving a gap G for introducing the sealant 200 (see Figure 2 ). For example, the encapsulation chamber 120 may be cylindrical, cubic, etc.

[0032] As Figure 1As shown, the electrical component 110 (or other workpiece) can be positioned within the encapsulation chamber 120 to provide a uniform gap G between the sidewall 112 of the electrical component 110 and the inner wall 134 of the housing 130. The electrical component 110 can be any device that can benefit from electrical insulation. For example, the electrical component 110 can be a circuit breaker, switch, motor, generator, battery, resistor, transistor, capacitor, inductor, transformer, relay, integrated circuit, microprocessor, etc. An exemplary circuit breaker component that requires electrical insulation can be a vacuum circuit breaker, such as Figure 9 the vacuum circuit breaker 900 shown.

[0033] Figure 2 is a cross-sectional view of the mold 100 during the encapsulation process Figure 1 The sealant 200 is a material used to encapsulate the electrical component 110 or other workpiece, thereby forming a composite casting. For example, the sealant 200 can be silicone rubber, ethylene propylene diene monomer (EPDM) rubber, polyurethane rubber, etc. The thickness of the sealant 200 can be any thickness that provides adequate electrical insulation. For example, the thickness of the sealant 200 can be from about 0.25 mm to about 100 mm, from about 0.5 mm to about 50 mm, from about 1 mm to about 25 mm, or from about 2 mm to about 5 mm. During the encapsulation process, the liquid sealant 200 is poured through a controllable valve 202 from a source into the gap G between the electrical component 110 and the encapsulation chamber 120. Once the electrical component 110 is encapsulated to the desired height with the sealant 200, the valve 202 is closed and the source of the liquid sealant 200 is removed. The sidewall 112 of the electrical component 110 can be at least partially encapsulated in the sealant 200, or alternatively, the liquid sealant can be allowed to also cover the upper surface 114 of the electrical component 110. The electrical component 110 can be directly rested on the plate 146 of the housing 130, or alternatively can be spaced apart from the plate 146 to allow the sealant 200 to also encapsulate the lower surface 116 of the electrical component 110.

[0034] Figure 3 is during the ejection process Figure 1Cross-sectional view of the mold 100 in []. After allowing the liquid sealant 200 to cure (i.e., allowing the sealant 200 to cool to a temperature below its melting point and return to a solid state), the plate 146 of the encapsulation chamber 120 can be removed. The contact surface 204 of the sealant 200 is the surface of the sealant 200 that is in direct contact with the housing 130 (especially the inner wall 134). The adhesive force between the contact surface 204 of the sealant 200 and the housing 130 requires additional force to eject the composite casting without damaging the electrical component 110 and / or the sealant 200. Through the orifice 148 in the outer wall 132 of the housing 130, gas is introduced from the air inlet 150 into the gas chamber 140 of the housing 130. As the gas pressure in the gas chamber 140 increases, the pressurized gas is forced through the pores of the permeable inner wall 134 of the housing 130 and against the contact surface 204 of the sealant 200 to uniformly push the sealant 200, thereby providing additional force to counteract the adhesive force. When the gas leaves the permeable inner wall 134 and enters the encapsulation chamber 120, a thin layer of gas separates the contact surface 204 of the sealant 200 from the encapsulation chamber 120. This thin layer of gas allows the composite casting to be ejected from the encapsulation chamber 120 with a significantly reduced ejection force F or significantly reduced damage to the electrical component 110 and / or the sealant 200.

[0035] Figure 4 is an isometric view of another exemplary mold 400 for encapsulating a workpiece such as a vacuum interrupter 900 or other electrical component using a silicone sealant 200. Figure 5 is Figure 4 an exploded view of the mold 400 in []. Figure 6 is Figure 4 a cross-sectional view of the mold 400 in []. The mold 400 is similar in operation to the mold 100 described above, but has additional features.

[0036] Referring together Figures 4 to 6, the mold 400 may include an encapsulation chamber 420 for receiving a vacuum breaker or other workpiece. The encapsulation chamber 420 may be defined by the internal volume of a housing 430. The housing 430 may include an outer wall 432, an inner wall 434, a top 436, and a bottom 438. The outer wall 432 may have a cylindrical shape. The outer wall 432 may also have one or more orifices 448 for receiving an air inlet 150. The inner wall 434 may also have a cylindrical shape, with an outer diameter smaller than the inner diameter of the outer wall 432. The inner wall 434 may be positioned within the outer wall 432 such that a gap G is formed between the inner wall 434 and the outer wall 432. The top 436 may be a flat disk having a plurality of locking notches 452 along its perimeter for receiving locking bolts 454 or other locking members. The top 436 may have a central opening 456 for receiving the workpiece and a liquid sealant 200. The top 436 may also have a pair of nested rings 458, 460 on its lower surface for maintaining the gap G between the outer wall 432 and the inner wall 434. The bottom 438 may also be a flat disk having a plurality of locking notches 462 along its perimeter and aligned with the locking notches 452 of the top 436 for receiving the locking bolts 454. If the workpiece is a vacuum breaker, then the upper terminal post 902 of the vacuum breaker 900 may extend through the central opening 456 in the top 436, and the bottom 438 may also have a central opening 464 for receiving the lower terminal post 904 of the vacuum breaker 900 and one or more annular orifices 466 for filling the encapsulation chamber 420 with the liquid sealant 200 from below. The bottom 438 may have a pair of matching nested rings 468, 470 on its upper surface, which are similar in size and shape to the nested rings 458, 460 of the top 436. The top and bottom nested rings 458, 460, 468, 470 space the outer wall 432 from the inner wall 434 and together with the lower surface of the top 436, the inner surface of the outer wall 432 and the inner wall 434, and the upper surface of the bottom 438 form a sealed air chamber 472. For example, the inner ring 460 on the top 436 may be positioned between the outer wall 432 and the inner wall 434 to further maintain the gap G that forms the air chamber 472 between the outer wall 432 and the inner wall 434. Similarly, the inner ring 470 on the bottom 438 may be positioned between the outer wall 432 and the inner wall 434 to further maintain the gap G that forms the air chamber 472 between the outer wall 432 and the inner wall 434. The locking bolts 454 may be removed from the top 436 and the bottom 438, thereby allowing the mold 400 to be disassembled (see Figure 5)for repair and / or replacement of parts. For example, the mold 400 may include an inner wall having various inner diameters. The inner wall 434 can be selected for each different vacuum breaker 900 or for each desired thickness of the sealant 200. Similarly, the mold 400 may include a pair of outer and inner walls having various heights. A pair of matching outer and inner walls 432, 434 can be selected for vacuum breakers having different heights.

[0037] Figure 7 is a cross-sectional view of another exemplary mold 400' similar to the Figure 6 mold. The mold 400' differs from the mold 400 in the modified housing 430'. The housing 430' may include an outer wall 432', an inner wall 434', a top 436', and a bottom 438'. Both the outer wall 432' and the inner wall 434' can have a cylindrical shape. The inflation chamber 440' can be formed by an inflation sidewall member 447' extending inward from the outer wall 432' to the inner wall 434'. The inflation sidewall member 447' can reinforce the outer wall 432'. The outer wall 432' can also have one or more orifices 448', each orifice serving as an air inlet to the inflation chamber 440'. Thus, in this embodiment, instead of having one air chamber between the outer and inner walls, a plurality of inflation chambers 440' provide a plurality of air chambers between the outer wall 432' and the inner wall 434'. This design can help avoid all pressure being released in an area that has been emptied by ejecting the workpiece, which can reduce the fluid buffering effect and cause the workpiece to stick to the ejection path. Additionally, feeding multiple inflation chambers instead of a single larger chamber can help generally equalize the pressure along the workpiece and help maintain the fluidized layer between the outer and inner walls. The inner wall 434' can be positioned within the outer wall 432' such that the inflation chambers are located within a gap G' between the inner wall 434' and the outer wall 432'. The top 436' can be a flat disk. The top 436' can have a central opening 456' for receiving the workpiece and the liquid sealant 200. The top 436' can also have a pair of nested rings 458', 460' on the lower surface for maintaining the gap G' between the outer wall 432' and the inner wall 434'. The bottom 438' can also be a flat disk. If the workpiece is a vacuum breaker, then the bottom 438' can also have a central opening 464' for receiving the lower terminal post 904 of the vacuum breaker 900 and one or more annular orifices 466' for filling the encapsulation chamber 420' with the liquid sealant 200 from below. The bottom 438' can have a pair of matching nested rings 468', 470' on the upper surface, which are similar in size and shape to the nested rings 458', 460' of the top 436'. The top and bottom nested rings 458', 460', 468', 470' keep the outer wall 432' and the inner wall 434' spaced apart.

[0038] The clearance G' of the modified mold 400' can be greater than the clearance G of the mold 400, thereby providing a greater total volume in the inflation chamber 440' compared to the total volume of the single sealed gas chamber between the outer wall and the inner wall.

[0039] Figure 8A is Figure 6 an isometric cross-sectional view of the outer wall 432 of the mold housing 430 of Figure 8B is Figure 7 an isometric cross-sectional view of the outer wall 432' of the mold housing 430' of , to which the inflation sidewall member 447' is attached. For example, comparing the outer wall 432 and the outer wall 432' applied to the common inner wall 434, the maximum diameter D of the outer wall 432 may be smaller than the maximum diameter D' of the outer wall 432'.

[0040] Figure 9 is a cross-sectional view of the mold 400, in which the exemplary vacuum interrupter 900 is partially surrounded by the silicone sealant 200 within the mold 400. The vacuum interrupter 900 may have a substantially cylindrical intermediate portion 906. The sealant 200 can be cured around the cylindrical intermediate portion 906 of the vacuum interrupter 900 within the encapsulation chamber 420. Gas can be introduced into the gas chamber 472 via the orifice 448, thereby releasing the contact surface 204 of the sealant 200 from the inner wall 434 as described above. The extended lower terminal post 904 can be pressed, or the bottom 438 can be removed, and the lower side of the electrical component 110 can be pressed to lift the composite casting from the encapsulation chamber 420. During the molding process, the lower terminal post 904 can be fixed to the bottom of the mold, such as by a lock nut or other fixing structure.

[0041] Figure 10 Presents a flowchart of a casting molding method. For example, a method of casting and molding a workpiece or other electrical component may include: (a) at 1001, providing a mold having a gas chamber between a solid outer wall and a permeable inner wall; (b) at 1002, positioning the workpiece or other electrical component within the mold; (c) at 1003, encapsulating the workpiece within the mold (although the top can optionally remain open); (d) at 1004, introducing a sealant into the mold and positioning it between the workpiece and the permeable inner wall; (e) at 1005, curing the sealant around at least a portion of the electrical component within the mold to form a composite casting; (f) at 1006, optionally opening the bottom end of the mold; (g) at 1007, introducing gas into the gas chamber to pass through the permeable inner wall, thereby separating the contact surface of the sealant from the mold; and (h) at 1008, removing the composite casting from the mold, such as by pressing the composite casting from the open bottom end to eject the composite casting from the top end of the mold.

[0042] The combined casting can be positioned as a final product within a cylindrical cover (e.g., a rigid housing). Teachings of exemplary encapsulated rod units can be found in U.S. Patent No. 7,852,180, the disclosure of which is incorporated herein by reference in its entirety. Teachings of an exemplary press-in mechanism with a membrane switch can be found in U.S. Patent No. 8,674,254, the disclosure of which is incorporated herein by reference in its entirety. It is desirable that there be no air gap between the vacuum interrupter and the cover. The sealant helps to avoid an air gap between the vacuum interrupter and the cover. This is particularly applicable to vacuum interrupters where silicone encapsulation serves as an electrically insulating mechanical interface layer between the vacuum interrupter and the cover as part of an encapsulated rod unit or other switchgear component.

[0043] As used in this document, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise. All technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art unless otherwise defined. As used in this document, the term "comprising" means "including but not limited to". When used in this document, the term "exemplary" is intended to mean "by way of example" and is not intended to indicate that a particular exemplary item is preferred or required.

[0044] In this document, when terms such as "first" and "second" are used to modify a noun, such use is only intended to distinguish one item from another and is not intended to require an order of precedence unless specifically stated. When used in conjunction with numerical values, the term "about" or "approximate" is intended to include values that are close to but not precisely equal to the numerical value. For example, in some embodiments, the term "about" or "approximate" may include values within + / - 10% of the value.

[0045] When used in this document, terms such as "top" and "bottom", "upper" and "lower", or "front" and "rear" are not intended to have an absolute orientation but are intended to describe the relative positions of various components with respect to each other. For example, when a device of which a component is a part is oriented in a first direction, a first component may be the "upper" component and a second component may be the "lower" component. If the orientation of the structure containing the components changes, the relative orientation of the components may be reversed, or the components may be in the same plane. The claims are intended to cover all orientations of devices containing such components.

[0046] The features and functions disclosed above, as well as alternatives, can be combined into many other different systems or applications. Those skilled in the art can make various substitutions, modifications, variations, or improvements that are currently unforeseen or unpredictable, each of which is also intended to be covered by the disclosed embodiments.

Claims

1. A mold for encapsulating an electrical component, the mold comprising: An encapsulation chamber for receiving the electrical component, the encapsulation chamber being defined by: A housing including a solid outer wall, a permeable inner wall, and an air chamber between the solid outer wall and the permeable inner wall, An open top, A lower opening, and A solid removable bottom positioned within the lower opening; And An air inlet configured to introduce a gas into the air chamber; Wherein the size and shape of the encapsulation chamber are set to receive the electrical component while leaving a gap for introducing a sealant around the electrical component, Wherein the mold is configured to cure the sealant around at least a portion of the electrical component within the mold to form a composite casting, and Wherein the mold is configured to eject the composite casting from the mold.

2. The mold according to claim 1, wherein the sealant comprises silicone rubber.

3. The mold according to claim 1, wherein the gap is 2 mm to 5 mm.

4. The mold according to claim 1, wherein: The air chamber includes a plurality of inflatable chambers positioned between the solid outer wall and the permeable inner wall; and The air inlet includes a plurality of orifices, each of the plurality of orifices leading to one of the inflatable chambers.

5. The mold according to claim 4, further comprising a plurality of inflatable chamber sidewall members extending from the solid outer wall to the permeable inner wall and forming the inflatable chambers.

6. The mold according to claim 1, wherein each of the solid outer wall, the permeable inner wall, and the air chamber is cylindrical.

7. The mold according to claim 1, wherein the solid bottom includes at least one ring positioned between the solid outer wall and the permeable inner wall to maintain a gap for forming the air chamber between the solid outer wall and the permeable inner wall.

8. The mold according to claim 7, wherein: The open top includes a flat disk having a central opening; and The flat disk includes at least one second ring positioned between the solid outer wall and the permeable inner wall to further maintain the gap for forming the air chamber between the solid outer wall and the permeable inner wall.

9. A casting molding method for encapsulating an electrical component, the casting molding method comprising: Providing a mold including: An encapsulation chamber defined by: A housing including a solid outer wall, a permeable inner wall, and an air chamber between the solid outer wall and the inner wall, An open top, A bottom, and An air inlet configured to introduce a gas into the air chamber; Positioning an electrical component within the mold; Introducing a sealant into the mold and between the electrical component and the permeable inner wall; Curing the sealant around at least a portion of the electrical component within the mold to form a composite casting; Introducing a pressurized gas into the air chamber to pass through the permeable inner wall, thereby separating the contact surface of the sealant from the mold; and Eject the combined casting from the mold.

10. The casting and molding method according to claim 9, wherein: the bottom of the mold is openable and closable; the bottom end of the mold is encapsulated before introducing the sealant; the bottom of the mold is opened before introducing the pressurized gas into the air chamber; and ejecting the combined casting includes, after opening the bottom, pressing the combined casting through the open top from the bottom.

11. The casting and molding method according to claim 9, wherein the electrical component comprises: a top; a bottom; a cylindrical wall; a first post extending from the top and positioned within the open top of the mold; and a second post extending from the bottom and positioned within the bottom end of the mold.

12. The casting and molding method according to claim 11, wherein introducing the sealant and curing the sealant encapsulate at least part of the electrical component in the sealant, with the top of the electrical component remaining exposed.

13. The casting and molding method according to claim 11, wherein introducing the sealant and curing the sealant encapsulate at least part of the electrical component in the sealant, with the bottom of the electrical component remaining exposed.

14. The casting and molding method according to claim 11, wherein introducing the sealant and curing the sealant encapsulate at least part of the electrical component in the sealant, with the top and the bottom of the electrical component remaining exposed.

15. The casting and molding method according to claim 9, wherein: the air chamber includes a plurality of inflatable chambers positioned between the solid outer wall and the permeable inner wall; the air inlet includes a plurality of orifices, each of the plurality of orifices leading to one of the inflatable chambers; and introducing the pressurized gas into the air chamber includes substantially equalizing the pressure in the air chamber by introducing the pressurized gas into each of the inflatable chambers.

16. The casting and molding method according to claim 9, wherein the electrical component is a vacuum interrupter.

17. The casting and molding method according to claim 9, wherein the sealant comprises silicone rubber.

18. The casting and molding method according to claim 17, wherein curing the sealant includes forming the combined casting of the silicone rubber with a thickness of 2 mm to 5 mm.

19. A mold for encapsulating a workpiece, the mold comprises: an encapsulation chamber defined by: a housing including a solid outer wall, a permeable inner wall, and an air chamber between the solid outer wall and the permeable inner wall, an open top, and a solid bottom, wherein the solid bottom includes at least one ring positioned between the solid outer wall and the permeable inner wall to maintain a gap forming the air chamber between the solid outer wall and the permeable inner wall; wherein: the air chamber includes a plurality of inflatable chambers positioned between the solid outer wall and the permeable inner wall, and The solid outer wall includes a plurality of air inlets, and each of the plurality of air inlets leads to one of the inflatable chambers in the inflatable chamber.

20. The mold according to claim 19, wherein the solid bottom includes a plurality of locking notches along the perimeter of the solid bottom, and each of the plurality of locking notches is configured to receive a locking member.

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