초록 ▼

The present invention provides a refrigerated merchandiser including a case defining a product display area. The product display area defines a highest temperature zone and a lowest temperature zone. The merchandiser includes a first product simulator positioned in the highest temperature zone of th

The present invention provides a refrigerated merchandiser including a case defining a product display area. The product display area defines a highest temperature zone and a lowest temperature zone. The merchandiser includes a first product simulator positioned in the highest temperature zone of the product display area to generate a first signal representative of the temperature of products positioned in the highest temperature zone of the product display area, and a second product simulator positioned in the lowest temperature zone of the product display area to generate a second signal representative of the temperature of products positioned in the lowest temperature zone of the product display area. The merchandiser also includes a controller in communication with the first and second product simulators. The controller is operable to adjust an outlet temperature set point in response to the first and second signals from the first and second product simulators.

대표청구항 ▼

I claim: 1. A refrigerated merchandiser, comprising: a case defining a product display area and an air passage having an inlet located adjacent a bottom of the product display area and that receives air from the product display area, the air passage further having an outlet that delivers air to the

I claim: 1. A refrigerated merchandiser, comprising: a case defining a product display area and an air passage having an inlet located adjacent a bottom of the product display area and that receives air from the product display area, the air passage further having an outlet that delivers air to the product display area, the product display area defining a highest temperature zone located adjacent the inlet of the air passage and a lowest temperature zone; an evaporator positioned in the air passage to refrigerate the air according to an outlet temperature set point; a fan positioned in the air passage to move the air through the passage; a first product simulator positioned in the highest temperature zone of the product display area to generate a first signal representative of the temperature of products positioned in the highest temperature zone of the product display area; a second product simulator positioned in the lowest temperature zone of the product display area to generate a second signal representative of the temperature of products positioned in the lowest temperature zone of the product display area; and a controller in communication with the first and second product simulators, the controller being operable to adjust the outlet temperature set point in response to the first and second signals from the first and second product simulators. 2. The refrigerated merchandiser of claim 1, wherein the case includes a rear wall separating in part the product display area from a vertical portion of the air passage, and wherein the lowest temperature zone in the product display area is located adjacent the rear wall. 3. The refrigerated merchandiser of claim 2, further comprising a plurality of apertures through the rear wall to communicate the air passage and the product display area. 4. The refrigerated merchandiser of claim 1, further comprising an outlet temperature sensor for generating an outlet temperature signal representative of the temperature of the air discharged from the outlet of the air passageway. 5. The refrigerated merchandiser of claim 4, wherein the controller is in communication with the outlet temperature sensor, and wherein the controller is operable to adjust flow of refrigerant through the evaporator in response to the outlet temperature signal. 6. The refrigerated merchandiser of claim 1, further comprising an inlet temperature sensor for generating an inlet temperature signal representative of the temperature of the air received by the inlet of the air passage, wherein the controller is in communication with the inlet temperature sensor. 7. The refrigerated merchandiser of claim 1, further comprising a saturated evaporator temperature sensor for generating a saturated evaporator temperature signal representative of the saturated evaporator temperature, wherein the controller is in communication with the saturated evaporator temperature sensor. 8. The refrigerated merchandiser of claim 1, wherein the first product simulator includes a temperature sensor for generating the first signal. 9. The refrigerated merchandiser of claim 1, wherein the second product simulator includes a temperature sensor for generating the second signal. 10. A method of controlling a refrigerated merchandiser, comprising: providing a case defining a product display area and an air passage having an inlet that receives air from the product display area and an outlet that delivers air to the product display area, the product display area defining a highest temperature zone and a lowest temperature zone; positioning an evaporator in the air passage to refrigerate the air according to an outlet temperature set point; positioning a fan in the air passage to move the air through the passage; generating a first signal representative of the temperature of products positioned in the highest temperature zone of the product display area using a first product simulator; generating a second signal representative of the temperature of products positioned in the lowest temperature zone of the product display area using a second product simulator; adjusting the outlet temperature set point in response to the first and second signals generated by the first and second product simulators; logging a first temperature value during frost-free operation of the evaporator, the first temperature value associated with at least one of the air entering the inlet of the air passage, the air exiting the outlet of the air passage, and saturated evaporator temperature; logging a second temperature value during frosted operation of the evaporator, the second temperature value associated with at least one of the air entering the inlet of the air passage, the air exiting the outlet of the air passage, and saturated evaporator temperature; calculating a difference of the first and second temperature values; and defrosting the evaporator when the difference exceeds a pre-determined value. 11. The method of claim 10, further comprising positioning the first product simulator adjacent to the inlet of the air passage. 12. The method of claim 10, further comprising: providing a rear wall in the case separating in part the product display area from a vertical portion of the air passage, the rear wall having a plurality of apertures to communicate the air passage and the product display area; and positioning the second product simulator adjacent to the rear wall. 13. The method of claim 10, further comprising: detecting an outlet temperature of the air discharged from the outlet of the air passage; calculating a temperature difference between the outlet temperature and the outlet temperature set point; and adjusting flow of refrigerant through the evaporator to decrease a magnitude of the temperature difference. 14. The method of claim 13, wherein detecting an outlet temperature of the air discharged from the outlet of the air passage occurs about every 1 to 3 seconds of operation of the refrigerated merchandiser. 15. The method of claim 10, wherein the first and second product simulators each define an acceptable temperature range, and wherein adjusting the outlet temperature set point in response to the first and second signals includes adjusting the outlet temperature set point when at least one of the first and second signals indicate that one of the first and second product simulators has a temperature outside of the acceptable temperature range. 16. The method of claim 10, wherein adjusting the outlet temperature set point occurs about every 1 to 2 hours of operation of the refrigerated merchandiser. 17. The method of claim 10, further comprising comparing the difference of the first and second temperature values with the pre-determined value. 18. The method of claim 10, wherein logging the first and second temperature values includes logging at least one of an inlet air temperature, outlet air temperature, and saturated evaporator temperature. 19. The method of claim 10, wherein logging the first and second temperature values includes logging at least one of a difference between outlet air temperature and inlet air temperature, and a difference between saturated evaporator temperature and inlet air temperature.