FIELD OF THE INVENTION

This invention relates generally to kilns. More particularly, disclosed and protected herein is a hinged protective collar for kilns that is foldable between an open configuration preventing wear and damage to the upper peripheral edge surface of the kiln during loading and unloading and a collapsed configuration, such as for storage and transport.

BACKGROUND OF THE INVENTION

Kilns are essential to the manufacture of ceramics, which, by definition, require high temperature treatment. During the firing stage, chemical and physical reactions occur that permanently alter the material. Proper firing of clay converts the relatively weak and malleable substrate into a rigid and strong structure. The final material characteristics of articles of ceramic are determined by a number of factors, including the preparation and composition of the clay substrate, the temperature at which it is fired, and any glazing that might be applied thereto.

One type of kiln often used by finished ware manufacturers to fire ceramic products is commonly referred to as a hobby kiln, which can be used for firing, curing, and heat treating. Kiln styles include the chamber raise kiln, the top loading kiln, and the front loading kiln. The chamber raise kiln is often referred to as a top hat kiln since an upper body portion with sides, a top, and an open bottom is raised and lowered by a winch system relative to a support surface for enabling the insertion, heat treatment, and removal of articles. A front loading kiln typically comprises a box shape with a vertically hinged front door.

Top loading kilns are perhaps the most common type of hobby kiln. A typical top loading kiln is indicated generally at10inFIG. 1. The top loading kiln10has a body portion formed by a fixed peripheral sidewall12and a bottom25. The sidewall12and the bottom25together define a firing chamber16for receiving articles to be heat treated. A lid14with a handle32is coupled to the sidewall12by a hinge arrangement18. The lid14can be retained in an open disposition by a support bar22or other means. When closed, the lid14seals off the chamber16to enable proper heating of the kiln10.

The sidewalls12of top loading kilns10can be of a variety of shapes, including round as inFIG. 4, square, oval, or faceted, such as by having from five to twenty or even more facets. For example, the kiln10inFIG. 1is faceted with ten sides while the kiln10inFIG. 3is faceted with eight sides. The thickness T of the sidewalls12can vary, but is commonly 2 and ½ to 3 and ½ or more inches. Similarly, the effective inner diameter D of kilns10varies depending on, among other things, the needs and budget of the artisan and the design of the manufacturer.

Electric heating elements20, often made from resistance wire, are disposed in grooves21on the interior surfaces of the sidewalls12. The kiln10receives power through a power cord30. Other kilns10are gas fired. A control box24with a control panel28enables control over the operation of the kiln10, and a plurality of venting louvers26enables heat to be dissipated from the control box24. The sidewall12, lid14, and bottom25of the kiln10are typically formed by blocks of firebrick, which can be dry fit or cemented together. The firebrick can be enveloped in a metal lining.

Firebrick is a refractory ceramic material built primarily to withstand high heat and to demonstrate low thermal conductivity, which saves energy and facilitates sustained high internal operating temperatures. In that regard, it will be noted that kilns10are fired not just to a temperature, but to what are typically referred to as cone levels, which account for time and temperature. The firebrick used in electric and gas-fired kilns10is often relatively porous thereby rendering the brick lighter, easier to form, and better thermal insulators than denser brick.

The sidewall12of the top loading kiln10has an upper peripheral surface15that is flat and horizontal for providing a good seal relative to the lower surface of the lid14. A tight seal is important for a number of reasons, including for energy efficiency and to enable the kiln10to reach desired cone levels. Furthermore, a good seal will help prevent caustic fumes from escaping from the firing chamber16and causing adverse effects on bystanders and surrounding components of the kiln10. Furthermore, certain kilns10rely on a tight seal to permit a negative pressure to be created by a downdraft vent system that, when installed and operational, limits the emission of fumes by evacuating them from the chamber16and exhausting them.

Unfortunately, while advantageous for its thermal and other properties, firebrick is very fragile. As such, the soft brick is vulnerable to chipping, breaking, and general wear. For example, as artisans repeatedly lean against the sidewalls12to reach into the firing chamber16, the firebrick at the upper peripheral edge surface15is often worn down over time and otherwise damaged. Furthermore, articles, such as ceramic structures and kiln furniture, can accidentally strike and damage the upper edge surfaces15of the sidewalls12while being inserted and removed. Further risk of damage and wear comes from the habit of some practitioners of propping the lid14of their kiln10open by placing a brick or other obstruction between the lid14and the upper edge surface15of the sidewall12.

Over time, therefore, a wearing away of the upper peripheral edge surface15leads to chips36and damaged edge portions34. The integrity of the seal between the lid14and the upper peripheral edge surface15can be compromised, particularly where the damage extends entirely from the inner edge to the outer edge of the upper peripheral edge surface15, thereby leading to reduced performance and potential harm to surrounding persons and structures. While repair of the damaged peripheral edge surface15is possible, it is expensive and inevitably decreases the life and value of the kiln10.

With an awareness of the foregoing, the present inventor recognized that a structure and method for protecting a kiln10during loading and unloading was needed and, to that end, invented the Kiln Brick Protective Collar of U.S. Pat. No. 8,523,563. The '563 patent disclosed a protective collar for kilns with a rigid body portion with a shape and size substantially corresponding to the shape and size of a portion of the upper peripheral edge surface of the kiln sidewall. With that, the protective collar advantageously can be disposed to rest atop the kiln sidewall to provide effective protection against damage to the kiln brick.

While the protective collar of the '563 patent represented a useful advance in the art, the present inventor has since appreciated a number of further advantages that could be achieved in relation to protective collars for kilns. For instance, protective collars for kilns that are configured to overlie a substantial portion of the kiln sidewall are inherently large. Although necessary to their function, the sheer size of the protective collar often renders it not only challenging to store and transport but also difficult to manage during installation and removal from the kiln. Additionally, it has been found that there are instances where the full size of a protective collar that may be designed to protect half or more of a kiln is not necessarily required.

In view of the foregoing, the present inventor appreciated that it would be advantageous to provide a protective collar for kilns that can achieve a larger, full size for overlying and protecting a substantial portion of a kiln sidewall but that can also be selectively reduced in size for installation and removal, for storage, and to protect a reduced span of the kiln sidewall where doing so would be sufficient.

SUMMARY OF THE INVENTION

Recognizing the advantages that could derive from improving upon even his own invention, the present inventor set forth with the basic object of providing a protective collar for kilns that can be adjusted from a broadened configuration traversing a given angular span to prevent wear and damage in relation to the upper surface of the kiln to a narrowed configuration traversing a reduced angular span.

An underlying object of the invention is to provide a protective collar for kilns that can be selectively expanded in angular range for use in protecting kiln brick against damage but that can also be selectively reduced in angular range for storage and transport and, where desirable, to protect kiln brick against damage over a reduced angular span.

A further object of the invention is to provide a protective collar for kilns that increases the useful life of the kiln and reduces the need for repairs thereto.

A further object of embodiments of the invention is to provide a protective collar for kilns that enables a tight seal between the body of the kiln thereby to improve energy efficiency and firing quality while preventing the deleterious effects of escaping gasses.

Another object of embodiments of the invention is to provide a protective collar for kilns that permits full or substantially full dimensional access to the firing chamber of the kiln for loading and unloading while protecting the fragile firebrick at the upper surface of the kiln.

Still another object of embodiments of the invention is to provide a protective collar for kilns that reduces the care and attention required in leaning over the kiln thereby improving comfort and ease while saving precious time in loading and unloading articles relative to the kiln.

These and in all likelihood further objects and advantages of the present invention will become obvious not only to one who reviews the present specification and drawings but also to those who have an opportunity to observe an embodiment of the hinged protective collar for kilns disclosed herein. Although the accomplishment of each of the foregoing objects in a single embodiment of the invention may be possible and indeed preferred, not all embodiments will seek or need to accomplish each and every potential advantage and function. Nonetheless, all such embodiments should be considered within the scope of the present invention.

In carrying forth the foregoing objects, one embodiment of the invention for a hinged protective collar is crafted for a kiln with a kiln sidewall that has a peripheral edge surface of a given shape, size, and thickness. The hinged protective collar has a rigid first body portion with a proximal end, a distal end, an upper surface, a lower surface, an inner edge, an outer edge, and a shape and size substantially corresponding to the shape and size of a portion of the peripheral edge surface of the kiln sidewall and a rigid second body portion with a proximal end, a distal end, an upper surface, a lower surface, an inner edge, an outer edge, and a shape and size substantially corresponding to the shape and size of a portion of the peripheral edge surface of the kiln sidewall. A hinge structure pivotally couples the first and second body portions. Under this construction, the first and second body portions of the hinged protective collar can be pivoted from a collapsed configuration to an expanded, use configuration.

In practices of the invention, the hinged protective collar is constructed for a kiln with a peripheral edge surface with a faceted shape. As such, each of the first and second body portions of the hinged protective collar has a given number of facets substantially corresponding in size, shape, and disposition to at least some of the facets of the peripheral edge of the kiln sidewall. For instance, the first and second body portions can cooperate when the hinged protective collar is in the expanded configuration to have plural facets corresponding in size, shape, and disposition to a plurality of facets or facet portions of a kiln with a peripheral edge surface with between 5 and 20 facets. Still more particularly, the first and second body portions of the hinged protective collar can cooperate when the hinged protective collar is in the expanded configuration to have facets corresponding in size, shape, and disposition to a plurality of facets of a kiln with a peripheral edge surface with 8, 10, or 12 facets.

In embodiments of the hinged protective collar, each of the first and second body portions has a width approximately equal to the thickness of the peripheral edge surface of the kiln sidewall. There can be an inner dimension between opposed inner edges of the first and second body portions when the hinged protective collar is in the expanded configuration approximately equal to an inner dimension between opposed inner edges of the peripheral edge surface, and there can be an outer dimension between opposed outer edges of the first and second body portions when the hinged protective collar is in the expanded configuration approximately equal to an outer dimension between opposed outer edges of the peripheral edge surface. Each of the first and second body portions can, for instance, have a width within thirty percent of the thickness of the peripheral edge surface of the kiln sidewall.

Embodiments of the hinged protective collar are contemplated wherein the first and second body portions cooperate when the hinged protective collar is in the expanded configuration to form a complete ring for entirely encircling the kiln sidewall while other embodiments are contemplated wherein the first and second body portions cooperate to span less than a complete ring. Where the hinged protective collar spans a complete ring, each of the first and second body portions can then span approximately 180 degrees of a circumference of the peripheral edge surface, and there can be first and second hinge structures that pivotally couple the first and second body portions.

It is further within the scope of the invention for each of the first and second body portions to have an aperture therein, and those apertures in the first and second body portions can be disposed to align when the hinged protective collar is in the collapsed configuration. For example, each of the first and second body portions could have a proximal aperture adjacent to the proximal end of the body portion and a distal aperture adjacent to the distal end of the body portion. When the hinged protective collar is in the collapsed configuration, the proximal apertures in the first and second body portions are disposed to align with one another and the distal apertures are disposed to align with one another.

According to practices of the invention, the hinge structure could be disposed at a mid-portion of a facet formed by proximal portions of the first and second body portions in combination. Stated alternatively, the proximal portions of the first and second body portions can cooperate to form a shape corresponding to one facet of the kiln with the hinge structure disposed midway therealong. In other practices, the hinge structure can be disposed at ends of facets formed by proximal portions of the first and second body portions in combination.

The type of hinge structure could vary within the scope of the invention. By way of non-limiting examples, the hinge structure could comprise a continuous hinge, alternatively referred to as a piano hinge, or the hinge structure could be formed with a living hinge.

Additionally, to prevent damage to the delicate kiln brick during application, removal, and moving of the hinged protective collar, the first and second body portions can have upturned proximal end portions that are angled away from the bottom surfaces of the body portions. With that, the end portions and the hinge structure will tend to be displaced from the surface of the kiln. Alternatively or additionally, the first and second body portions can have upturned distal end portions that are angled away from the bottom surfaces of the body portions, again tending to prevent the collar from damaging the kiln brick.

The first and second body portions of the hinged protective collar could be founded on plates of rigid material, such as a metal or another rigid material. In certain practices of the invention, an upper layer can be fixed to the upper surface of the first body portion, and an upper layer can be fixed to the upper surface of the second body portion. The upper layers could, by way of example and not limitation, comprise layers of a polymeric material, such as a rubber material, a foam material. The upper layers could have flat upper surfaces, or they could be arched or otherwise shaped.

The hinged protective collar can be employed in a method for protecting a peripheral edge surface of a kiln. That method can begin with providing a kiln with a peripheral kiln sidewall that has a peripheral edge surface of a given shape, size, and thickness and then selecting a hinged protective collar. The hinged protective collar can comprise a rigid first body portion with a proximal end, a distal end, an upper surface, a lower surface, an inner edge, an outer edge, and a shape and size substantially corresponding to the shape and size of a portion of the peripheral edge surface of the kiln sidewall; a rigid second body portion with a proximal end, a distal end, an upper surface, a lower surface, an inner edge, an outer edge, and a shape and size substantially corresponding to the shape and size of a portion of the peripheral edge surface of the kiln sidewall; and a hinge structure that pivotally couples the first and second body portions whereby the first and second body portions of the hinged protective collar can be pivoted from a collapsed configuration to an expanded, use configuration.

The protective collar can be applied to the kiln with the lower surfaces of the first and second body portions facing the peripheral edge surface of the kiln sidewall and with the shapes of the first and second body portions of the hinged protective collar and the peripheral edge surface substantially aligned. The hinged protective collar can be applied in the collapsed configuration and pivoted to the expanded configuration or left in the collapsed configuration. Alternatively, the hinged protective collar could be applied already partially or completely in the expanded configuration. The kiln and the hinged protective collar can be considered to be a combination.

One will appreciate that the foregoing discussion broadly outlines the more important goals and features of the invention to enable a better understanding of the detailed description that follows and to instill a better appreciation of the inventor's contribution to the art. Before any particular embodiment or aspect thereof is explained in detail, it must be made clear that the following details of construction and illustrations of inventive concepts are mere examples of the many possible manifestations of the invention.

