Patent Application
20130140417
The present disclosure relates to refrigeration systems, and particularly to thermostats or thermal switches of refrigeration systems.
Refrigeration systems include refrigerated bins and display cases. Such refrigerated display cases are common in convenience stores, grocery stores, and other commercial applications. For example, some display cases can include upright units with shelves to stock and display refrigerated food or frozen items.
Such refrigeration systems for commercial display and storage can include an evaporator to chill surrounding air within a refrigeration unit. This evaporator typically includes refrigeration tubing, which can accumulate frost from prolonged use. To address the frost issue, a thermostat or thermal switch can be mounted to refrigeration tubing of the evaporator portion of the refrigeration system. This thermal switch then controls on-off cycles of a heater that removes or prevents frost from accumulating on the evaporator refrigeration tubing or coils.
Certain refrigeration systems can include a generally elongated evaporator unit having refrigeration tubing that runs back and forth within a length of the evaporator unit. The refrigeration tubing has U-bends (also known as return bends) at the ends of the evaporator unit. In other words, the refrigeration tubing coil runs within the evaporator space, looping back and forth into and out of the unit multiple times. Thus, there are several evaporator tube U-bends at the end of the evaporator unit. These U-bends are in relatively close proximity to each other, that is, they are tightly bended and bunched leaving little free space.
Space constraints of the evaporator create challenges both during manufacture of refrigeration systems, and for maintenance—especially when the evaporator unit is positioned tightly within the larger refrigeration system to minimize space used by components used in the refrigeration cycle. Specifically, such evaporator units have significant size constraints on the ends for adding a thermal switch. Adding the thermal switch to the end of an evaporator unit is preferred for subsequent access such as for replacement, as well as initial assembly. In addition to the relatively small space available for the thermal switch, this thermal switch needs to be ergonomically accessible both for assembly and for replacement. For example, in some refrigeration units, it is necessary to install the thermal switch using one hand.
Techniques disclosed herein include a mounting clip for use with so called large body thermal switches, which have a length substantially longer than a diameter of refrigeration tubing. Such thermal switches typically include one end having a semi-cylindrical surface area designed to contact and follow the shape of refrigeration tubing, thereby increasing surface area contact between the thermal switch and refrigeration tubing. As such, there are significant physical constraints for the clip both from the thermal switch size and the closely spaced U-bends.
One embodiment includes a mounting clip that provides an easy way to attach the thermal switch to the refrigeration tubing. For example, one embodiment includes a snap-fit design. The mounting clip snaps onto the thermal switch, and then snaps onto the refrigeration tubing as well. The mounting clip can be further sized to meet the space constraints defined by the evaporator unit end section. The mounting clip can be attached and removed with one hand, secures contact between the thermal switch and the refrigeration tube, and fits within the bounds of clustered return ends of refrigeration tubing.
Additionally, although each of the different features, techniques, configurations, etc., herein may be discussed in different places of this disclosure, it is intended that each of the concepts can be executed independently of each other or in combination with each other. Accordingly, the one or more present inventions, embodiments, etc., as described herein can be embodied and viewed in many different ways.
Also, note that this preliminary discussion of embodiments herein does not specify every embodiment and/or incrementally novel aspect of the present disclosure or claimed invention(s). Instead, this brief description only presents general embodiments and corresponding points of novelty over conventional techniques. For additional details and/or possible perspectives (permutations) of the invention(s), the reader is directed to the Detailed Description section and corresponding figures of the present disclosure as further discussed below.
The foregoing and other objects, features, and advantages of the invention will be apparent from the following more particular description of preferred embodiments herein, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, with emphasis instead being placed upon illustrating the embodiments, principles, concepts, etc.
Techniques disclosed herein include a mounting clip for use with large body thermal switches, which can have a length substantially longer than a diameter of refrigeration tubing. Such thermal switches typically include one end having a concave semi-cylindrical surface area designed to contact and follow the shape of refrigeration tubing, thereby increasing surface area contact between the thermal switch and refrigeration tubing. As such, there are significant physical constraints for the clip both from the thermal switch size and the closely spaced U-bends.
In general, example embodiments can include a one-piece or two-piece mounting clip that removable presses and holds the thermal switch against a refrigeration tube by encompassing both the refrigeration tube and the thermal switch.
Referring now to
In
Referring now to
Note that top, bottom, and side portion labels are for distinction among/between parts of the mounting clip for clarity relative to each other but do not necessarily indicate orientation during use. During use of the mounting clip, such as when attached to an evaporation unit, the top portion of the loop may be oriented in a side (vertical) position relative to gravity, or otherwise oriented depending on a particular orientation of refrigeration tubing.
With the elongated member 110 formed from a material having some elastic or tensile properties (such as metal or plastic), the mounting clip 100 can be squeezed together or otherwise manipulated to separate the ends 111 and 112 such that the mounting clip is in an open position (not shown). In an open position, the mounting clip 100 can open or flex sufficiently to be passed over refrigeration tubing 180. After being passed over the refrigeration tubing 180, the ends 111 and 112 can be interlocked, the force of which secures the thermal switch 170 to the refrigeration tubing 180. Locking and interlocking the ends 111 and 112 can be performed either manually or using a locking/unlocking tool. In this example embodiment, the ends 111 and 112 are illustrated as having opposing bends adapted to form hooks that interlock with each other. Note that other latching mechanisms can be substituted for the elongated member to interlock with itself.
Returning to
In some embodiments, a thickness of the elongated member and loop geometry can be selected such that the loop is sized to fit between U-bends of adjacent refrigeration tubing, such as bunched return bends on the end of an evaporator unit.
Referring now to
In
Referring now to
Note that by manufacturing the prongs using a metallic or plastic or equivalent material, the prongs can flex sufficiently to permit the second end 171 of the thermal switch to be pressed against the mounting clip 200, and then hold the thermal switch 170 against the or within the mounting clip 200. If the thermal switch 170 has a perimeter lip 173, then the prongs can flex sufficiently to pass over the lip, and then return towards an initial position and contact the cylindrical body of the thermal switch 170. In other words, the prongs enable the thermal switch to be walked or worked on to the mounting clip (angled installation) or snapped on to the mounting clip without angled installation. The thermal switch can be snapped onto the mounting clip prior to attaching the mounting clip to the refrigeration tube. In an alternative embodiment, the mounting clip 200 can include a structural plate that is spot welded, riveted, crimped, or otherwise attached to the elongated member. The structure plate then includes the prongs instead of the elongated member 210.
The first end 211 of the elongated member 210 and the second end 212 of the elongated member are positioned at the bottom portion 224 of the loop. In other words, the bending of the elongated member 210 is such that the ends terminate near each other on the bottom side 224 of the loop. The first end 211 of the elongated member and the second end 212 of the elongated member are configured to define a separable opening 227 to the loop such that the elongated member 210 and the thermal switch 170 can be pressed onto the refrigeration tube 180 via the separable opening 277. Accordingly, the first end 211 of the elongated member 210 and the second end 212 of the elongated member 212 move apart from each other when pressed over the refrigeration tube 180 and then return to an approximate initial position after passing the refrigeration tubing 180. In one configuration, ends 211 and 212 can be bent at an angle that assists the loop to separate when the opening 227 is pressed with sufficient force against the refrigeration tube 180. With the elongated member 210 formed from a material having some elastic or tensile properties (such as metal or plastic), the mounting clip 200 can be pressed over the refrigeration tube 180, causing the ends 211 and 212 to separate widening the opening 227 to allow passage of the loop over the refrigeration tube 180.
In some embodiments, the a thickness of the elongated member and loop geometry can be selected such that the loop is sized to fit between U-bends of adjacent refrigeration tubing, such as bunched return bends on the end of an evaporator unit.
While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present application as defined by the appended claims. Such variations are intended to be covered by the scope of this present application. As such, the foregoing description of embodiments of the present application is not intended to be limiting. Rather, any limitations to the invention are presented in the following claims.
