Sealing arrangement for an explosion proof enclosure

Abstract

An explosion proof enclosure assembly with a first enclosure (110) defining a port (112) with a threaded portion (114) and a tube (120) joinable to the first enclosure (110). The tube (120) defines a threaded portion (122). The explosion proof enclosure further having the threaded portion (122) of the tube (120) being threaded into the threaded portion (114) of the first enclosure (110) to provide a threaded connection arrangement (130). A flame path (140) defined by the threaded connection arrangement (130). The explosion proof enclosure further having a sealing arrangement (150) having a ring (152) mounted around the tube (120) and a seal (154) compressed by the ring (154) for providing sealing between the tube (120) and the first enclosure (110).

Description

SEALING ARRANGEMENT FORAN EXPLOSION PROOF ENCLOSUREReference to Related Application

[0001] This application is being filed on June 26, 2025, as a PCT International Patent Application and claims the benefit of and priority to Indian Provisional Patent Application No. 202411049584, filed on June 28, 2024, the disclosure of which is incorporated herein by reference in its entirety.Background

[0002] Enclosures may often be placed in areas of hazardous gaseous conditions.Enclosures may include electrical components which may be at risk of sparking. Enclosures within hazardous conditions may also be at risk of allowing outside elements, such as water, into the enclosure at connection points for terminals. These outside elements may damage the electrical components.Summary

[0003] One aspect of the present disclosure relates to an explosion proof enclosure. The explosion proof enclosure including a first enclosure defining a port with a threaded portion and a tube joinable to the first enclosure. The tube defines a threaded portion. The explosion proof enclosure further includes the threaded portion of the tube being threaded into the threaded portion of the first enclosure to provide a threaded connection arrangement, a flame path defined by the threaded connection arrangement; and a sealing arrangement including a ring mounted around the tube and a seal compressed by the ring for providing sealing between the tube and the first enclosure.

[0004] Another aspect of the present disclosure relates to a method of assembling an explosion proof enclosure assembly. The method including inserting a tube through a sealing body, threading the tube into a port of an explosion proof enclosure, and compressing the sealing body against the explosion proof enclosure to seal an interface between the tube and the explosion proof enclosure.

[0005] Another aspect of the present disclosure relates to an explosion proof assembly. The explosion proof assembly including a first enclosure defining a port with a threaded portion and a tube joinable to the first enclosure, the tube defining a threaded portion. The threaded portion of the tube being threaded into the threaded portion of the first enclosure to provide a threaded connection arrangement. A flame path defined between the threaded portion of the tube and the threaded portion of the first enclosure. A sealing arrangementincluding a ring and at least one seal, and wherein the sealing arrangement is configured to seal the flame path within the port of the first enclosure. The first enclosure includes one of a groove or a plurality of openings surrounding the port for retaining the ring against an exterior of the first enclosure.Brief Description of Drawings

[0006] FIG. l is a perspective view of an explosion proof enclosure assembly of the present disclosure;

[0007] FIG. 2 is a perspective cross-sectional view of the explosion proof enclosure assembly of FIG. 1;

[0008] FIG. 3 is an enlarged perspective cross sectional view of a sealing nut of the explosion proof enclosure assembly of FIG. 1;

[0009] FIG. 4 is a perspective view of an alternate embodiment of the sealing arrangement of an explosion proof enclosure assembly;

[0010] FIG. 5 is a perspective view of an alternate embodiment of the sealing arrangement of an explosion proof enclosure assembly;

[0011] FIG. 6 is an alternate embodiment of the sealing arrangement of an explosion proof enclosure assembly of FIG. 4;

[0012] FIG. 7 is a perspective view of an alternate embodiment of the sealing arrangement of an explosion proof enclosure assembly.Detailed Description

[0013] Aspect of the present disclosure are directed to an explosion proof enclosure assembly. In some embodiments, the assembly includes a connection point between a tube and an enclosure. The assembly may include a sealing body. The first enclosure and the tube having threaded portion which mate to define a flame path. The flame path allows flames to dissipate and prevent explosions.

[0014] Further aspects of the present disclosure are directed toward sealing arrangement of an enclosure. A sealing body may join to the tube and enclosure. The sealing arrangement includes at least one seal. In some examples, the sealing arrangement may include a first seal and a second seal. The first seal creates an axial seal, and the second seal creates a radial face seal against the enclosure. The first and second seals limit the ingress of water into the enclosure.

[0015] Referring to FIG. 1-3, the present disclosure relates to an explosion proof assembly. The explosion proof assembly includes a first enclosure 110, a tube 120 joinable to the first enclosure 110, a threaded arrangement 130, a flame path 140, and a sealing arrangement 150. The first enclosure 110 defines a port 112 with a threaded portion 114. The tube 120 defines a threaded portion 122 and a passage 123. The threaded arrangement 130 is defined by the threaded portion 122 of the tube 120 and the threaded portion 114 of the first enclosure 110. The threaded arrangement 130 is configured to join the threaded portion of the tube 120 engaging with the threaded portion 114 of the first enclosure 110. The flame path 140 is defined between the connection of the threaded portion 122 of the tube 120 and the threaded portion 114 of the first enclosure 110. A sealing arrangement 150 includes at least one seal and the sealing arrangement 150 is configured to seal the first enclosure 110. In some examples, the at least one seal can be a first seal 154 and a second seal 156.

[0016] In some examples, first enclosure 110 may enclose a circuit breaker. The first enclosure 110 may be an explosion proof enclosure within a hazardous environment. As such, in certain instances, sparks may occur which can cause a flame.

[0017] The flame path 140 allows for flames caused by the spark in the hazardous environment to dissipate before exiting the enclosure 110. In some examples, the threaded arrangement 130 is a defined number of threads allowing for the dissipation of the flame. The threaded arrangement is in compliance with at least one or all of UL1203, IEC 60079-0, IEC 60079-1, or IEC 60079-7. In some examples, the threads may be straight threads. In other examples, the threads may be tapered threads.

[0018] In some examples, a second enclosure 170 may also be joined to the tube 120 at an opposite end 180 of the tube from an end 182 of the tube 120 attached to the first enclosure 110. The second enclosure 170 may include terminals having wires which pass through the tube 120. As such, wires may pass through the passage of the tube 120 and connect with the circuit breaker.

[0019] The sealing arrangement 150 prevents the ingress of water into the first enclosure 110. Conventional methods do not provide adequate sealing and can limit the dissipation of the flames within the flame path. The sealing arrangement 150 can define at least one seal which seals against the ingress of water from entering the first enclosure 110. In some examples, the sealing arrangement 150 can include a sealing body 152 and at least one seal 154, 156. In other instances, a liquid seal can be formed around the threaded portion without affecting the flame path.

[0020] Referring to FIGS. 2 and 3, the first enclosure 110 engages with the sealing arrangement 150. The sealing arrangement 150 includes the sealing body 152, a first seal 154, and a second seal 156. The first enclosure 110 defines a sealing body retaining groove 116 to receive the sealing body 152. Further, the first enclosure 110 may be machined to form the groove 116 which accommodates a face of the sealing body 152. The sealing body 152 may be a sealing nut which can be joined fastened around the circumference of the tube 120 and received within the groove 116. In some instances, the sealing body 152 may referred to as a ring. A face 157 of the sealing body 152 may fit within the groove 116. In some instances, the groove 116 may be formed by machining the first enclosure 110.Advantageously, the sealing arrangement 150 allows improved sealing against the ingress of water with minimal machining and without affecting the flame path 140.

[0021] The sealing arrangement 150 allows the retention of seals 154, 156 against the tube and the first enclosure 110. The sealing body 152 defines a first groove 158. The first groove 158 of the sealing body 152 retains the first seal 154 and creates an axial face seal against the first enclosure 110. The first seal 154 may seal against the enclosure 110 while received within the groove 116. In some examples, the first seal 154 may be an O-ring. In some examples, the sealing body 152 is machined to define the first groove 158. The sealing body 152 may further define a threaded portion 160. As will be explained in greater detail later, the threaded portion 160 is engageable with a second threaded portion 128 of the threaded portion 122 of the tube 120.

[0022] Further, the tube 120 may include a first groove 124. The first groove 124 of the tube 120 may allow the retaining of the second seal 156 against an interior wall of the sealing body 152. As such, the second seal 156 seals against the sealing body 152 and around the tube 120 within the groove. In some examples, the second seal 156 may be an O-ring. In some examples, the tube 120 may be machined to define the first groove 124.

[0023] The flame path 140 is defined by between the threaded portion 114 of the port 112 and a first threaded region 126 of the threaded portion of the tube 120. As such, if a spark occurs, the flames may travel through and dissipate within the flame path 140. A second threaded region 128 of the threaded portion 122 of the tube 120 may extend beyond the threaded portion 114 of the port 112 on the exterior side 118 of the first enclosure 110. The second threaded portion 128 allows the tightening of the sealing body 152 to the tube 120. As such, the sealing body 152 may be screwed onto the threaded portions 122 of the tube 120 to seal the enclosure 110. The tightening of the sealing body 152 along the threaded arrangement 130 creates an axial face seal with the first seal 154 and a radial seal with thesecond seal 156. The port 112 does not require the use of tape to seal against water. Advantageously, the sealing arrangement 150 provides both an axial seal and radial seal to prevent water from entering the enclosure 110 without affecting the flame path 140, requiring tape to seal the enclosure 110, and / or with minimal machining required to the tube 120 or enclosure 110.

[0024] FIG. 4 illustrates an alternate embodiment of the sealing arrangement 150 of an explosion proof enclosure assembly 200 of the present disclosure. The sealing arrangement 150 may include a sealing body 252. The sealing body 252 includes an overmolded interior seal 254 on the threaded portion 256 of the sealing body 152. For instance, the sealing body 252 may be matingly engaged to the threaded portion 122 of the tube 120 outside of the flame path 140 and against the enclosure 110. The overmolded interior seal 254 may prevent water ingress into the first enclosure 110 without affecting the flame path 140. The overmolded interior seal 254 beneficially does not compromise the flame path and needs no additional machining to the enclosure.

[0025] FIGS. 5 and 6 illustrates another embodiment of the sealing arrangement 150 of an explosion proof enclosure assembly 300. In the example explosion proof enclosure assembly 300, the sealing arrangement 150 includes a sealing body 352 with a seal. The sealing body 352 may be a compression ring. The sealing body may be fastened to the first enclosure by fasteners. The sealing body defines an area 353 which receives the at least one seal. The area 353 may instead be a groove 358 defined within a face 359 of the compression ring facing the first enclosure. The fasteners 380 may extend through the compression ring to join the compression ring to the first enclosure. Referring to 5, the compression ring may be machined to have the groove 358. The groove 358 may receive a seal 356. an O-ring. In other examples, the compression ring 352 is a piece of sheet metal (see FIG. 6) with a first portion 354 receiving the first seal 356. The area is defined by a space between the compression ring and the first enclosure. The sealing body 352 may join to the enclosure 110 by fasteners 380. The enclosure may include a plurality of openings 382 to receive the fasteners 380. In other examples, the sealing body 352 may seal against the first enclosure 110 via a liquid seal gasket. It will be appreciated that the sealing body 352 when fastened to the first enclosure 110 seals against the tube 120 without threadingly engaging the tube 120. In some embodiments, the first seal 356 at the first portion 354 of the sealing body 352 may be a liquid seal. Advantageously, no machining is required to tube 120. A further benefit of the embodiment is functionality of providing sealing to the enclosure without affecting the flame path 140.

[0026] FIG. 7 illustrates an alternate embodiment of the sealing arrangement 150 an explosion proof enclosure assembly 400 of the present disclosure. The sealing arrangement 150 includes a sealing body 452. The sealing body 452 may be a lock nut or flat washer with a gasket 454 on an enclosure facing side of the sealing body 452. Referring to FIG. 7, the sealing body 452 may include a threaded portion 456 which engages a threaded portion 122 of the tube 120. The gasket 454 may seal directly against the enclosure 110.

[0027] Another aspect of the present disclosure is a method of assembling an explosion proof enclosure assembly 100. The tube 120 threadingly engaged to the port 112 of the first enclosure 110. An end of the tube 120 may be inserted through the sealing body 152. The sealing body 152 may be threadingly engaged to the tube 120 and tightened against the first enclosure 110. The end of the tube 120 may threadingly engaged to the port 112 of the second enclosure 170.

[0028] The various embodiments described above are provided by way of illustration only and should not be construed to limit the claims attached hereto. Those skilled in the art will readily recognize various modifications and changes that may be made without following the example embodiments and applications illustrated and described herein, and without departing from the full scope of the following claims.

Claims

What is claimed:

1. An explosion proof assembly comprising: a first enclosure defining a port with a threaded portion; a tube joinable to the first enclosure, the tube defining a threaded portion; the threaded portion of the tube being threaded into the threaded portion of the first enclosure to provide a threaded connection arrangement; a flame path defined by the threaded connection arrangement; and a sealing arrangement including a ring mounted around the tube and a seal compressed by the ring for providing sealing between the tube and the first enclosure.

2. The explosion proof assembly of claim 1, further comprising a second enclosure joinable to an end of the tube opposite an end joinable to the first enclosure.

3. The explosion proof assembly of claim 1, wherein the threaded portion of the tube includes a threaded region extending beyond the threaded portion of the first enclosure to an exterior side of the first enclosure.

4. The explosion proof assembly of claim 1, wherein the ring holds the seal at an interface between the tube and the enclosure.

5. The explosion proof assembly of claim 1, wherein the ring is a sealing nut with a threaded portion.

6. The explosion proof assembly of claim 5, wherein the threaded portion of the sealing nut engages with the threaded portion of the tube extending beyond the first enclosure.

7. The explosion proof assembly of claim 5, wherein the sealing nut defines a first groove retaining the seal, and wherein the seal is an O-ring.

8. The explosion proof assembly of claim 6, wherein the seal is pressed against a face of the first enclosure and the ring.

9. The explosion proof assembly of claim 7, wherein the first groove has an open side facing towards the first enclosure, wherein the seal is a first seal that is axially compressed between the sealing nut and the first enclosure, and wherein the tube defines a second groove having an open side facing toward the ring, wherein a second seal is retained within the second groove and is radially compressed between the tube and the ring.

10. The explosion proof assembly of claim 5, wherein the sealing nut includes a first seal overmolded into the threaded portion of the sealing nut.

11. The explosion proof assembly of claim 4, wherein the ring is a washer secured to the first enclosure by threaded fasteners and the seal faces the first enclosure.

12. The explosion proof assembly of claim 4, wherein the ring is a compression ring fastened to the first enclosure, the compression ring defining an area which receives the at least one seal within a space at an interface between the tube, the first enclosure, and the compression ring, and wherein fasteners extend through the compression ring to join the compression ring to the first enclosure.

13. The explosion proof assembly of claim 12, wherein the area is a groove defined within a face of the compression ring facing the first enclosure.

14. The explosion proof assembly of claim 12, wherein the compression ring is a piece of sheet metal, and the area is defined by a space between the compression ring and the first enclosure.

15. The explosion proof assembly of claim 4, wherein the ring includes a gasket.

16. The explosion proof assembly of claim 1, wherein the seal includes a liquid seal.

17. The explosion proof assembly of claim 1, wherein the ring is attached by fasteners to the first enclosure.

18. The explosion proof assembly of claim 1, wherein the flame path is defined the threaded portion of the tube engaging the port and the threaded portion of the port.

19. The explosion proof assembly of claim 1, wherein the seal is a first seal, wherein the first seal axially compressed between the first enclosure and the ring, wherein the assembly further includes a second seal, and wherein the second seal is radial compressed between the ring and the tube.

20. A method of assembling an explosion proof enclosure assembly comprising: inserting a tube through a sealing body; threading the tube into a port of an explosion proof enclosure; compressing the sealing body against the explosion proof enclosure to seal an interface between the tube and the explosion proof enclosure.

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