Patent Application
20170175424
The present disclosure relates generally to electrical disconnect handles, and more particularly to an electrical disconnect handle assembly having enhanced security, sealing, and cleaning features.
Electrical disconnects are used in a variety of commercial applications, both indoors and outdoors, for energizing and de-energizing electrical devices, such as lights, fans, pumps, generators and the like. Typically, an electrical disconnect includes an external handle connected to a switch element located within an electrical enclosure, or box. The handle may or may not include lockout features to prevent unauthorized operation of the associated electrical device.
As will be appreciated, electrical disconnects and associated electrical enclosures find wide industrial application, and thus they may be employed in a variety of environments. Some environments may be subject to rain (for outdoor applications), water spray (for indoor applications in which a hygienic work space is required) and/or dust. In addition, due to the increasing intensity of weather events, it may become important for electrical devices to withstand temporary or permanent submersion.
The National Electrical Manufacturers Association (NEMA) and Underwriters Laboratories (UL) provides standards for protection provided by certain enclosure “types.” For example, NEMA Type 6/6P enclosures must provide protection from ingress of solid foreign objects, as well as the ingress of hose directed water and water during temporary or prolonged submersion at a limited depth. Similarly, the International Electrotechnical Commission (IEC) also provides standards for protection of enclosures. For example, an enclosure meeting the IEC's International Protection (IP) Code IP67, IP68 or IP69 must provide protection from dust, as well as protection from powerful jets of water and/or total immersion of the enclosure. In addition, NEMA/UL50E type 6, 6p and IEC equivalent IP67, IP68 provide standards for enclosures subjected to temporary submersion (on the order of minutes) and permanent submersion (on the order of hours or days).
Further, the Occupational Safety & Health Administration (OSHA) provides standards for lockout of electrical disconnects using one or more external locks. Such lockout controls can be important when machinery is being serviced to ensure the safety of workers in the area. Under 29 C.F.R. §§1910.269, OSHA provides standards for such “Hazardous energy control (lockout/tagout)” procedures. Finally, in applications such as health care and food service industries, a variety of independent hygiene/sanitary standards (e.g., National Sanitation Foundation (NSF) standards; American National Standards Institute (ANSI), the US Department of Agriculture (USDA), Food Safety and Inspection Service (FSIS), International Association of Milk, Food and Environmental Sanitarians (IAMFES), American Meat Institute (AMI)), as well as harmonized industry standards must be adhered to so that the handles and other external surfaces of electrical disconnects can be thoroughly cleaned on a periodic basis. Similar European standards also exist.
As can be appreciated, problems exist with the existing handle and seal designs for electrical disconnects which may not be capable of simultaneously meeting all of the aforementioned sealing, lockout, and cleanability requirements. Accordingly, it would be desirable to provide an improved load switch handle and seal assembly that includes enhanced locking and sealing features that provide a desired high degree of moisture and water resistance and which is easily cleanable to meet applicable hygiene/sanitary standards.
A handle assembly may include a handle having a grasping portion, a handle seal recess, and a hub engaging portion. A hub can have a lock receiving surface and a handle engaging portion. A shaft may be receivable within the hub, the shaft having first and second ends, the first end engaged with the handle, and the second end comprising an actuating surface that is rotatable by rotating the grasping portion of the handle. A first seal may be disposed within the handle seal recess. The first seal may engage a sealing face of the hub to prevent moisture ingress between the handle and the hub.
A handle assembly can include a handle having a grasping portion, a handle seal recess, and a hub engaging portion. A huh may have a lock receiving surface, a handle engaging portion and first and second hub seal recesses. A shaft may be receivable within the hub. The shaft may include first and second ends, the first end engaged with the handle, the second end comprising an actuating surface that is rotatable by rotating the grasping portion of the handle. A first seal comprising a V-ring may be disposed within the handle seal recess and the first hub seal recess. The V-ring may engage the first hub seal recess to prevent moisture ingress between the handle and the hub. A second seal may be disposed in the second hub seal recess. The second hub seal recess may be disposed about a central portion of the shaft. The second seal may comprise an X-ring. Opposing sealing surfaces of the X-ring seal engage the second hub seal recess and the central portion of the shaft to prevent moisture ingress between the hub and the shaft.
A handle assembly is disclosed, comprising a handle having a grasping portion, a handle seal recess, and a hub engaging portion. A hub may have a lock receiving surface, a handle engaging portion and first and second hub seal recesses. A shaft may be receivable within the hub. The shaft may have first and second ends, the first end engaged with the handle, the second end comprising an actuating surface that is rotatable by rotating the grasping portion of the handle. A first seal may be a V-ring disposed within the handle seal recess and the first hub seal recess. The V-ring may engage a sealing face of the hub to prevent moisture ingress between the handle and the hub. The handle and hub may further comprise respective lock receiving surfaces for receiving a shank portion of a lock therebetween. The lock receiving surface of the handle may comprise a handle ledge portion disposed opposite a handle lip portion, and the lock receiving surface of the hub may comprise a hub ledge portion disposed opposite a hub lip portion.
By way of example, a specific embodiment of the disclosed device will now be described, with reference to the accompanying drawings, in which:
A handle assembly is disclosed that includes redundant sealing, locking and cleanability features rendering the assembly suitable for a variety of industrial and commercial applications. As will be described, a redundant sealing system is disclosed that enables the handle assembly to comply with waterproofing standards (e.g., NEMA-UL50E type 4, IEC IP66), submersion standards (e.g., NEMA-UL50E type 6/6P, IEC IP67/68), and standards governing exposure to high pressure waterjets/steam (e.g., IEC IP69 or IP69K (ISO)), among others. In addition, the disclosed handle assembly can include elements that reduce or eliminate the formation of crevice or pockets within the assembly, thus making it appropriate for sanitary (i.e., food service, healthcare) applications. Further, the disclosed handle assembly may include locking features that facilitate the use of a multiply-locked system to provide enhanced security against unauthorized activation or deactivation of an associated load.
Referring now to
As will be appreciated, the presence of angular surfaces within the handle assembly 1, and the absence of small crevices within the assembly, enable effective cleaning of the assembly with or without the locks installed. This can be important where the handle assembly 1 is used in foodservice, healthcare or other applications in which sanitary/hygiene standards apply.
Referring to
As will be appreciated, in some embodiments, the hub 8 and plate member 16 may be integrally formed. An example of this is where the hub and plate member are molded or otherwise formed from a polymer material, or are formed from molded or cast metal. In such cases, the fifth seal 42 may be eliminated.
It will be appreciated that the illustrated seals 34-42 may be formed of any of a variety of elastomeric materials as will be described in greater detail later. In addition, different combinations of seal materials and types may be used in place of, or in addition to, one or more of the illustrated seals. Finally, it will be understood that not all of the seals may be required for a particular application of the handle assembly 1. For example, in some applications, a desired sealing level may be achieved by using only the first seal 34. In other applications, only the first through third seals 34-38 may be used. Various combinations and arrangements of the disclosed seals are contemplated without departing from the disclosure.
Referring now to
The illustrated embodiment shows an exemplary V-ring used as the first seal 34. As will be appreciated, the first seal 34 may be employed to prevent water ingress during cleaning and/or immersion of the handle assembly 1. The illustrated V-ring 34 includes a body portion 44, a lip portion 46, and a living hinge portion 48. The body portion 44 may be received within a circumferential handle seal recess 50 formed in the handle 2. In one embodiment, the V-ring is press-fit into the handle seal recess 50, though this is not critical and the V-ring could be engaged within the handle seal recess using a suitable adhesive. The lip portion 46 may protrude from the handle seal recess so that it is presented axially toward a sealing face 52 of the hub 8. In one embodiment, the sealing face 52 is part of a circumferential first hub seal recess 54 formed in a handle engaging portion 56 of the hub 8. Thus arranged, the lip portion 46 contacts the sealing face 52 of the hub 8 when the handled 2 is engaged with the hub. As the lip portion 46 engages the sealing face 52 it flexes about a living hinge portion 48, thereby increase the sealing area between the lip portion 46 and the sealing face 52 of the hub 8. As arranged, the first seal 34 prevents moisture, dust or other foreign materials from passing between the handle 2 and hub 6. The first seal 34 and the handle seal recess 50 may be sized so that the first seal 34 remains fixed to the handle 2 such that it rotates with respect to the sealing face 52 of the hub 8 when the handle is rotated. The reverse arrangement is also contemplated, and the first seal 34 could be fixed to the hub 8 and could rotate with respect to the handle 2 as the handle is rotated during operation.
The second and third seals 36, 38 may be disposed within a second seal recess 58 formed in the hub 8. The second seal recess 58 may be sized and configured to hold the second and third seals 36, 38 in a stacked relationship between the hub 8 and a central portion 60 of the shaft 28. In the illustrated embodiment, the hub engaging portion 4 of the handle 2 engages the second seal 36 when the handle is coupled to the hub 8 and applies a compressive force to the second seal. This compressive force presses the second seal 36 into the third seal 38 so that the third seal engages a bottom shoulder 62 of the second seal recess 58. In the illustrated embodiment, the second seal 36 is an O-ring while the third seal 38 is an X-ring. As such, when the O-ring 36 pressed into the X-ring 38, the O-ring extends into the concave surface of the X-ring between the lobes 64, thus causing the lobes 64 to press against the central portion 60 of the shaft 28 and against the surfaces of the hub within the second seal recess 58.
As arranged, the second and third seals 36, 38 prevent moisture, dust or other foreign materials from passing between the handle 2, hub 8, and shaft 28. The second and third seals 36, 38 thus act as a secondary seal against the ingress of material passing the first seal 34. The second and third seals 36, 38 and the second seal recess 58 may be sized so that the second and third seals remain fixed to the hub 8, and rotate with respect to the central portion 60 of the shaft 28 when the handle 2 and shaft are rotated. The reverse arrangement is also contemplated, and the second and third seals 36, 38 could be fixed to the central portion 60 of the shaft 28 and could rotate with respect to the hub 8 as the handle 2 is rotated during operation.
The fourth seal 40 may be disposed within a third hub seal recess 66 formed in a central portion 68 of the hub 8. The third hub seal recess 66 may be positioned within the hub 8 so that the second hub seal recess 58 is disposed between the third hub seal recess and the first hub seal recess 54. The second and third hub seal recesses 58, 66 may be axially separated from each other by a shoulder portion 70 of the hub 8, thereby creating two separate seal recesses within the hub. It will be appreciated that this is not critical, and in some embodiments the second and third hub seal recesses could be connected or could together be a single recess.
The fourth seal 40 may be positioned within the third hub seal recess 66 so that it seals against a lower central portion 72 of the shaft 28. The lower central portion 72 and the central portion 60 of the shaft 28 may be adjacent to each other, and in one non-limiting exemplary embodiment the lower central portion may have a diameter that is larger than a diameter of the central portion. In the illustrated embodiment, a shoulder portion 74 of the shaft 28 engages the fourth seal 40 when the shaft is coupled to the hub 8 and the handle 2 and presses the fourth seal 40 against the shoulder portion 70 of the hub, thus retaining the fourth seal within the third hub seal recess 66. In one non-limiting exemplary embodiment the fourth seal 40 is a Simmering. The fourth seal 40 may be sized to be press fit into the third hub seal recess 66, and it may also be sized so that a gap “g” is formed between the fourth seal and the shoulder portion 74 of the shaft 28. The gap “g” may ensure that no contact, and thus no friction, occurs between the fourth seal 40 and the shaft 28 during operation of the handle assembly 1.
As arranged, the fourth seal 40 prevents moisture, dust or other foreign materials from passing between the hub 8 and shaft 28. The fourth seal 40 thus act as a tertiary seal against the ingress of material passing the first, second and third seals 34, 36, 38. The fourth seal 40 and the third seal recess 66 may be sized so that the fourth seal 40 remains fixed to the hub 8, and rotates with respect to the shaft 28 when the handle 2 and shaft are rotated. The reverse arrangement is also contemplated, and the fourth seal 40 could be fixed to the shaft 28 and could rotate with respect to the hub 8 as the handle 2 is rotated during operation.
The fifth seal 42 may be received within a circumferential plate seal recess 76 formed in a lower portion 78 of the hub 8. The fifth seal 42 may be presented within the plate seal recess so that it seals against a plate surface 80 of the plate member 16 when the hub 8 is fixed to the plate member. Thus arranged, the fifth seal 42 prevents moisture, dust or other foreign materials from passing between the hub 8 and the plate member 16. In the illustrated embodiment, the fifth seal 42 is an O-ring. As previously noted, in some embodiments the hub 8 and plate member 16 will be formed as a single piece, thus obviating the need for the fifth seal 42.
It will be appreciated that the illustrated embodiment includes specific seal types, that such arrangements are not critical and other types of seals can also be used, a non-limiting listing of which includes Types S, L and E V-rings, O-rings, X-rings, hollow O-rings, square rings, Simmerings, Simmering inflatable (i.e., air pocket) seals, gaskets, formed in place gaskets, and the like.
The first through fifth seals 34-42 can be made from one or more elastomeric materials. In one embodiment, all of the seals are made from the same type of elastomer, while in other embodiments the seals can be made from different elastomeric compositions and/or hardnesses. It will be appreciated that the choice of elastomeric material used for the first through fifth seals 34-42 may be selected to best suit the environment in which the handle assembly 1 will be subjected. A non-limiting exemplary listing of suitable elastomeric materials for the first through fifth seals 34-42 include rubber, nitrile, butadiene, synthetic rubber including ethylene-propylene (EPM, EPR, EPDM), nitrile rubber (NBR), Hydrogenated Nitrile Butadiene Rubber (HBNR), highly saturated nitrile rubber (HSN), neoprene, chloroprene, VMQ or PVMQ silicone rubber, polyester urethane (AU), polyether urethane (EU); fluoropolymer, FVMQ fluorosilicone, fluoromethyl ketone (FMK, FFMK) or a combination thereof. In non-limiting exemplary embodiments the first through fifth seals 34-42 can also have hardnesses of between 40-90 Shore A. In addition, for some embodiments, the elastomeric material used for the first through fifth seals 34-42 can have a desired degree of oil and/or chemical resistance.
In some embodiments, different seal materials can be used for the different seals 34-42 to obtain a universal or almost universal chemical compatible seal. For example, the first seal (V-ring) 34 could be formed from Viton, while the second and third seals (O-ring, X-ring) 36, 38 could be formed from a different material (i.e., one that is resistant to materials for which Viton is unsatisfactory). The fourth seal (Simmering) 40 could also be formed from Viton. Such an arrangement could provide resistance to ingress of a larger number of different chemicals/materials than an arrangement using only a single seal material for all seals in the assembly. The aforementioned combination is merely exemplary, and non-limiting, and a variety of other combinations can be employed depending on the particular installation. The disclosed redundancy of the seal compatibilities may complement and strengthen the resulting chemical barrier to a wide array of chemicals to which the handle assembly 1 will be subject.
As can be seen in
Referring now to
As can be seen, the handle ledge portions 100 comprise flat vertical ledges that together form a triangular shaped raised portion 104. The raised portion 104 can be centrally disposed about the axis A-A (see
In some embodiments, the handle 2 may be molded from two different materials, including a structural polymer skeleton layer and softer over-layer that provides an enhanced tactile feel. Such dual-shot molding provides a solid continuous surface around the entire handle 1, including areas not protected by seals. The resulting surface can be smooth, free of crevices, and easy to clean.
The disclosed handle 2 may have a smooth outer surface free of pockets or ribs/no pockets/ribs. Cosmetic appeal can also be enhanced as a dual color may be imparted to the handle 2, allowing an appropriate color choice to satisfy high visibility requirements desired to satisfy applicable standards. For example, the coloration of the handle 2 may comply with national safety color standards of ANSI Z535.
Like the handle, the hub 8 may include a plurality of lock receiving surfaces including a plurality of hub ledge portions 112 and a plurality of hub lip portions 114. The illustrated embodiment includes three hub ledge portions 112 and three hub lip portions 114 corresponding to the three handle ledge and lip portions 100, 102 of the handle. It will be appreciated that this is not critical, and fewer or greater numbers of hub ledge and lip portions can be used without departing from the disclosure.
As can be seen, the hub ledge portions 112 comprise flat ledges that together form the handle engaging portion 56. The handle engaging portion 56 is centrally disposed about the axis A-A (see
As can also be seen, the hub 8 employs smooth surfaces and a relatively shallow profile, which minimizes or eliminates crevice formation and facilitates cleaning. As mentioned, this can be advantageous for applications that require adherence to sanitary standards.
The geometry and features of the hub 4 and handle 2 make them manufacturable from a wide variety of materials, a non-limiting list including metal (e.g., stainless steel, copper, brass, aluminum), polymer (e.g., thermoplastics, thermosets), and ceramics. Further, the hub 4 and handle 2 can be manufactured using any of a variety of processes, a non-limiting list including machining, molding and casting. Using the aforementioned processes and materials enable the hub 4 and handle 2 to be manufactured to the surface finish/roughness requirements of applicable sanitary standards. Further, in some embodiments, one or more surfaces of the hub 4 and handle 2 can be provided with an antimicrobial coating, which may be applied as a resin coating, an electrocoating, a powder coating or the like.
The end face 120 of the shaft may include a lateral slot 121 that passes through an end portion of the central fastener recess 90. Within the lateral slot 121 may dispose a key slot 123. The key slot 123 may be sized and configured to receive a portion of a load switch, as will be described further in relation to
As previously noted, during operation the shaft 28 rotates with the handle 2. Thus, the distal portion 86 of the shaft 28 includes a pair of flat sides 116 that correspond to similar flat sides 118 (
As shown in
Referring now to
As can be seen, the opposing surfaces of the hub and handle lip and ledge portions are configured in a manner such that water, dust or other contaminants will not accumulate within the handle assembly 1. Thus, the surfaces of the handle 2 and hub 8 can be angled and/or a large space is provided between surfaces to prevent such accumulation
While certain embodiments of the disclosure have been described herein, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision additional modifications, features, and advantages within the scope and spirit of the claims appended hereto.
