Patent Application
20140209767
The disclosure relates generally to water heaters, and more particularly, to a mounting bracket for a water heater for mounting a temperature sensor, a gas valve, a power delivery unit, a controller and/or any other suitable object or device to the water heater.
Water heaters are used in homes, businesses and just about any establishment having the need for heated water. A conventional water heater typically has at least one heating element or “heater,” such as a gas-fired burner and/or electric heating element. Each water heater also typically has at least one thermostat or controller for controlling the heater. The controller typically receives signals related to the temperature of the water within the water heater tank, often from a temperature sensor that is thermally engaged with the water in the water heater tank.
In some instances, a water heater may operate in accordance with a first temperature set point and a second temperature set point. The difference between the first and second temperature set point may be referred to as the temperature differential of the water heater. When temperature signals from the temperature sensor indicate that the water temperature is below the first set point, for example when the water temperature is below about 120° F., the controller may turn on the heater and the water within the water heater tank begins to heat. After some time, the water temperature within the water heater tank will increase to the second set point, which, for example may be about 140° F. At this point, the controller may cause the heater to reduce its heat output or, alternatively, causes the heater to turn off. This heat cycle begins again when the water temperature within the water heater tank cools down below the first set point, such as below about 120° F.
For a gas fired water heater, a temperature sensor, a gas valve and a controller are often mounted relative to the water heater tank. The controller typically receives a temperature signal from the temperature sensor. The temperature sensor often protrudes into and is thermally coupled to the water in the water heater tank. The controller typically is programmed to control the gas valve such that the temperature of the water in the water heater tank remains between the first and second temperature set points, as described above. For an electric water heater, a temperature sensor, a power delivery unit and a controller may be mounted to the water heater tank. In this case, the controller may control the power delivery unit such that the temperature of the water in the water heater tank is kept between the first and second temperature set points.
What would be desirable is an improved mounting bracket for mounting the temperature sensor, the gas valve, the power delivery unit, the controller and/or any other suitable object or device to the water heater.
The present disclosure relates generally to an improved mounting bracket for mounting a temperature sensor, a gas valve, a power delivery unit, a controller and/or any other suitable object or device to a water heater. An illustrative but non-limiting example of the disclosure may be found in a mounting bracket that includes a polymeric body that has a sensor portion configured to receive a temperature sensor. The sensor portion may have a distal end that extends into and supports the temperature sensor within the water tank. In some cases, the sensor portion may be an elongated stem that has an internal well for receiving the temperature sensor. The polymeric body may also include a first threaded portion that is configured to threadably engage a threaded spud of the water heater such that when the threaded portion threadably engages the threaded spud of the water heater, the sensor portion extends into the water tank of the water heater. In some embodiments, the mounting bracket may include a component retaining region. The component retaining region may be use to retain a gas valve, a power delivery unit, a controller and/or any other suitable object or device relative to the water heater.
A shell may be disposed over and surround at least a portion of the sensor portion. In some instances, the shell may be formed from a different material than the polymeric body. For example, in some embodiments, the polymeric body may include a nylon material while the shell may include a metal material such as stainless steel or brass. In some cases, the shell may be mechanically deformed (e.g. crimped) to engage a mating feature on the sensor portion to help secure the shell to the sensor portion. Alternatively, the shell may be attached to the sensor in other manners, such as, but not limited to, threadably engaging the sensor portion, through adhesives, shrink wrapping, etc. In some instances, a cavity may be formed between the shell and the sensor portion. In some cases, this cavity may be at least partially filled. For example, the cavity may be at least partially filled with a thermally conductive silicone gel, water from the water tank of the water heater, or any other suitable material.
The following description should be read with reference to the drawings. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the disclosure. The disclosure may be more completely understood in consideration of the following detailed description of various embodiments in connection with the accompanying drawings, in which:
While the disclosure is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the disclosure to the particular examples described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure.
The following description should be read with reference to the drawings, in which like elements in different drawings are numbered in like fashion. The drawings, which are not necessarily to scale, depict several examples that are not intended to limit the scope of the disclosure. Although examples of construction, dimensions, and materials are illustrated for the various elements, those skilled in the art will recognize that many of the examples provided have suitable alternatives that may be utilized.
As can be seen, water heater 10 includes a temperature sensor 28. In some cases, temperature sensor 28 may enter water tank 12 at a location laterally offset from gas control unit 18. In some instances, however, temperature sensor 28 may instead be located behind gas control unit 18, and in some cases, may be supported and retained by a common mounting bracket such as that described more fully below. In any event, water tank 12 may include an aperture 30 that is sized and configured to accept temperature sensor 28. This can be seen in
Wiring harness 62 may be configured to extend from temperature sensor assembly 49 and to a gas control unit, such as the gas control unit 18 illustrated in
Bracket 32 may be formed of any suitable material. In some cases, bracket 32 may include non-metallic materials such as a polymeric material, glass, ceramic, plastic, and the like. In some cases, bracket 32 may be manufactured as a single piece by injection molding a nylon material such Hylon®, available from Entec Polymers in Manchester, Tenn. The thermal conductivity of such non-metallic materials may be less than those of metallic materials, and as a result, may partially thermally isolate the temperature sensor assembly 49 from the water in the water tank 12, but may be less expensive to produce than a metallic well. It is contemplated that in some cases, bracket 32 may not be formed entirely from the same material, or bracket 32 may not be formed as a single piece.
Sensor portion 36 of the bracket 32 may include an elongated stem extending from component retaining region 33. Sensor portion 36 may include an internal well 39 (shown in more detail in
In some instances, distal end region 42 may have a reduced cross-sectional area relative to remaining regions 37, 38 and 40 of sensor portion 36. However, it is contemplated that in some cases, the cross-sectional area of distal end 42 may be the same as, or substantially the same as the remaining regions 37, 38 and 40 of sensor portion 36. In some embodiments, distal end 42 may include a cutting element (not explicitly shown) disposed at or near the tip. In some instances, the cutting element may include a blade-like feature. The cutting element may be capable of puncturing and/or piercing a plastic sheet or barrier commonly wrapped around the water tank 12 of many water heaters during installation of the bracket 32. It is contemplated that in some cases, the cutting element may be omitted from the design.
Referring to
It is further contemplated that shell 50 may allow for near-zero change in the thermal time constant of sensor portion 36 and/or the temperature sensor relative to a bracket with no shell 50. In some instances, shell 50 may have a shape similar to the profile of thread lead-in portion 40 and distal end region 42 of the sensor portion 36. However, this is not required. The distance between sensor portion 36 and shell 50 may be exaggerated in the Figures to better illustrate the different components. It is contemplated that shell 50 may be sized and shaped as desired to achieve the desired spacing between sensor portion 36 and shell 50. In some instances, shell 50 may be formed of stainless steel. However, it is contemplated that shell 50 may be formed of any suitable material, such as, but not limited to, brass, other metals or metal alloys, ceramics, polymers, or polymer blends.
In some embodiments, bracket 32 may also include two (or more) bosses 44 on a first lateral side, and two (or more) bosses 44 on a second opposing lateral side. While bracket 32 is shown having four bosses 44, it is contemplated that bracket 32 may have any number of bosses 44 as desired, for example, but not limited to, one, two, three, or more. Additionally, it is contemplated that bosses 44 may be disposed on fewer, or more, than two lateral sides of the bracket. Bosses 44 may provide, among other things, an area for torque to be applied directly to the bracket 32 during installation. For example, an installation tool may grip and apply torque to bosses 44 to threadably engage threaded region 38 of sensor portion 36 with the threaded water heater spud on a water tank 12. In some instances, bosses 44 may further include a rib 46 disposed between adjacent bosses 44. Rib(s) 46 may provide additional support to the bracket 32, and may also help prevent an installation tool from contacting the component retaining region 33 of bracket 32 during installation.
Referring now to
In some instances, there may be a gap 58 between the shell 50 and the sensor portion 36 such that a layer of water (or other fluid) may be disposed between the shell 50 and the sensor portion 36 of bracket 32. This may reduce the volumetric flow rate of water over the surface of sensor portion 36 while still allowing water to contact and thermally engage sensor portion 36. A reduced volumetric flow rate (compared to a sensor portion 36 with no shell 50) may reduce water related degradation of the sensor portion while still maintaining low cost and good controller functionality. In some cases, one or more holes may be added to the shell 50 to allow water to flow through the shell 50, but at a reduced the volumetric flow rate relative to when no shell 50 is provided. In some cases, at least part of the shell 50 may be made from a screen or grate that allows water to flow through but at a reduced volumetric flow rate.
It is further contemplated that shell 50 may allow for near-zero change in the thermal time constant of sensor portion 36 and/or the temperature sensor relative to a bracket with no shell 50. It is contemplated that the size and shape of shell 50 may be adjusted to regulate the size of gap 58 and thus the amount of water allowed between shell 50 and sensor portion 36 when bracket 32 is engaged with a water tank. It is further contemplated that the number of crimps 56 and/or size of the crimps 56 may be adjusted to help control the amount of water flow between shell 50 and sensor portion 36 when bracket 32 is engaged with a water tank. In some embodiments, shell 50 may extend distally beyond the distal end of distal end region 42, although this is not required. This may create a cavity 52 at the distal end of shell 50. In some instances, such a cavity 52 may be filled with a thermally conductive silicone gel (not explicitly shown) to facilitate heat transfer from the shell 50 to the distal end region 42 of the sensor portion 36, which is where the temperature sensor of the temperature sensor assembly 49 may be located. In some instances, other thermally conductive materials may be disposed within cavity 52, when cavity 52 is provided. It is contemplated that in some embodiments, a thermally conductive adhesive may be disposed within cavity 52 to help secure shell 50 to sensor portion 36.
Sensor portion 136 may include a shell 150 configured to threadably engage second threaded region 135. Shell 150 may include a threaded region 142 configured to engage second threaded region 135. A sealing member 146, such as an O-ring or gasket may be positioned between shell 150 and the open end region 148. The sealing member 146 may help prevent water from entering cavity 152 within shell 150 and engaging and possibly damaging the temperature sensor 128. An outer surface of the proximal end of shell 150 may form a thread lead-in region 140 disposed between a distal end region 144 of shell 150 and first threaded region 138. Thread lead-in region 140 may be configured to help guide the sensor portion 136 into the aperture 30 of the water tank 12 with proper alignment for the first threaded region 138 to engage the threaded spud in the water tank 12. In some embodiments, the thread lead-in region 140 may have zero draft for maximum effectiveness, but this is not required. When first threaded region 138 is engaged with the threaded water heater spud, distal end region 144 may be disposed within water tank 12. As shown, distal end region 144 may house a temperature sensor 128 such that when the bracket is engaged with the water tank 12, the temperature sensor 128 is in at least partial thermal communication with the water in the water tank 12. In some cases, the temperature sensor 128 may engage the inside surface of the shell 150.
In some instances, distal end region 144 of shell 150 may have a reduced cross-sectional area relative to the sensor portion 136. However, it is contemplated that in some cases, the cross-sectional area of distal end region 144 may be the same as, or substantially the same as the sensor portion 136. In some embodiments, distal end region 144 may include a cutting element (not explicitly shown) disposed at or near the tip. In some instances, the cutting element may include a blade-like feature. The cutting element may be capable of puncturing and/or piercing a plastic sheet or barrier commonly wrapped around the water tank 12 of many water heaters during installation of the bracket 32. It is contemplated that in some cases, the cutting element may be omitted from the design.
Shell 150 may be constructed from the same material as the remaining regions of sensor portion 136 or may be constructed from a different material. It is contemplated that sensor portion 136 may be formed of a relatively inexpensive material, such as nylon, while shell 150 may be formed of a material more resistant to water degradation. In some instances, shell 150 may be formed of brass. However, it is contemplated that shell 150 may be formed of any material desired, such as, but not limited to: stainless steel, other metals or metal alloys, ceramics, polymers, or polymer blends. In some instances, the distal end region 144 of shell 150 may be cylindrically shaped. However, this is not required. It is contemplated that the distal end region 144 may take any shape desired. In some instances, the shape of the distal end region 144 may generally conform to the shape of the temperature sensor 128.
In some embodiments, distal end region 242 may include a shell or shell 250 configured to protect distal end region 242 from water related degradation. Shell 250 may be disposed over distal end region 242 and secured to the sensor portion 236. In some instances, shell 250 may be formed by shrink wrapping a polymeric material that is disposed over the distal end region 242. The shrink wrap material may be any material desired to provide the desired protection from water related degradation. In some cases, the shell 50 may include a dip coating that is dip coated on the outer surface of the distal end region 242 of the sensor portion 236. In some embodiments, shell 250 may be larger than distal end region 242.
In some cases, a cavity 252 may be present between shell 250 and distal end region 242, but this is not required. In some instances, and when a cavity 252 is provided, the cavity 252 may be filled with a thermally conductive silicone gel (not explicitly shown) to facilitate heat transfer. It is contemplated that in some embodiments, a thermally conductive adhesive may be disposed within cavity 252 to help secure shell 250 to sensor portion 236. In other embodiments, shell 250 may be sized and shaped to generally conform to the outer surface of distal end region 242. In some cases, the cavity 252 may be filled with water from the water tank when the bracket is installed on a water heater. In some cases, one or more holes may be added to the shell 250 to allow water to flow into and out of the cavity 252, but at a reduced the volumetric flow rate relative to when no shell 250 is provided. In some cases, at least part of the shell 250 may be made from a screen or grate that allows water to flow through but at a reduced volumetric flow rate. It is contemplated that shell 250 may be of any size or shape desired. For example, in some instances shell 250 may extend over thread lead-in portion 240 and/or beyond the distal end of distal end region 242, as desired.
In some embodiments, shell 250 may include a cutting element 254 disposed at or near the tip. In some instances, the cutting element may include a blade-like feature. The cutting element may be capable of puncturing and/or piercing a plastic sheet or barrier commonly wrapped around the water tank 12 of many water heaters during installation of the bracket 32. It is contemplated that in some cases, the cutting element may be omitted from the design.
An outer surface of the proximal end of shell 350 may form a thread lead-in region 340 disposed between a distal end region 354 of shell 350 and first threaded region 338. Thread lead-in region 340 may be configured to help guide the sensor portion 336 into the aperture 30 of the water tank 12 (see
In some instances, distal end region 354 of shell 350 may have a reduced cross-sectional area relative to the sensor portion 336. However, it is contemplated that in some cases, the cross-sectional area of distal end 354 may be the same as, or substantially the same as the sensor portion 336. In some embodiments, distal end 354 may include a cutting element (not explicitly shown) disposed at or near the tip. In some instances, the cutting element may include a blade-like feature. The cutting element may be capable of puncturing and/or piercing a plastic sheet or barrier commonly wrapped around the water tank 12 of many water heaters during installation of the bracket 32. It is contemplated that in some cases, the cutting element may be omitted from the design.
Shell 350 may be constructed from the same material as the remaining regions of sensor portion 336 or may be constructed from a different material. It is contemplated that sensor portion 336 may be formed of a relatively inexpensive material, such as nylon, while shell 350 may be formed of a material more resistant to water degradation. In some instances, shell 350 may be formed of a heat resistant polymer. However, it is contemplated that shell 350 may be formed of any material desired, such as, but not limited to: stainless steel, brass, other metals or metal alloys, ceramics, polymers, or polymer blends. In some instances, the distal end region 354 of shell 350 may generally conform to the shape of the temperature sensor 328, as shown in
The disclosure should not be considered limited to the particular examples described above, but rather should be understood to cover all aspects of the disclosure as set out in the attached claims. For example, it is contemplated that features shown and described with respect to one Figure may be applied to illustrative brackets shown and described with respect to other Figures. More generally, various modifications, equivalent processes, as well as numerous structures to which the disclosure can be applicable will be readily apparent to those of skill in the art upon review of the instant specification.
