# US 10,368,659 B2 · Refrigerated display case > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,368,659 B2 - Document ID: US10368659B2 - Status: Granted - Kind: B2 - Application number: 15/569,163 - Filed: 2016-05-13 - Published: 2018-05-31 - Granted: 2019-08-06 - Earliest claimed: 2015-06-16 - Assignees: AHT Cooling Systems GmbH - Applicants: Aht Cooling Systems GmbH - Inventors: Reinhold Resch - Web page: https://patentgrep.com/patent/US10368659B2 ## CPC - A47F 3/0439: {Cases or cabinets of the open type (A47F3/0482 takes precedence)} - F25B 13/00: Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02) - F25B 49/005: {of safety devices (F25B49/02 and F25B49/04 take precedence)} - F25D 11/00: Self-contained movable devices, e.g. domestic refrigerators - F25B 2400/12: Inflammable refrigerants - A47F: SPECIAL FURNITURE, FITTINGS, OR ACCESSORIES FOR SHOPS, STOREHOUSES, BARS, RESTAURANTS OR THE LIKE; PAYING COUNTERS - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS - F25D: REFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR (refrigerated showcases A47F3/04; thermally-insulated vessels for domestic use A47J41/00; refrigerated vehicles, see the appropriate subclasses of classes B60 - B64; containers with thermal insulation in general B65D81/38; heat-transfer, heat-exchange or heat-storage materials, e.g. refrigerants, or materials for the production of heat or cold by chemical reactions other than by combustion C09K5/00; thermally-insulated vessels for liquefied or solidified gases F17C; air-conditioning or air-humidification F24F; refrigeration machines, plants, or systems F25B; cooling of instruments or comparable apparatus without refrigeration G12B) ## Abstract A refrigerated display case (1) with at least one unit composed of a plurality of wall groups, namely a bottom group (11), a rear wall group (12), and a top group (13), which delimit a refrigerated chamber (4) at the bottom, at the back, and at the top, and with a cooling device (5) that has a refrigerant circuit and whose components at least include a compressor (51), an evaporator (50), a condenser (52), and an electric control unit (55). A refrigerated display case that is climate-friendly, efficient, and simultaneously safe to operate is achieved in that propane is contained as a refrigerant in the refrigerant circuit, with a filling capacity of more than 150 g. ## Claims ### Claim 1 A refrigerated display case (1) with at least one unit composed of a plurality of wall groups, namely a bottom group (11), a rear wall group (12), and a top group (13), which delimit a refrigerated chamber (4) at a bottom, at a back, and at a top, and with a cooling device (5) that has a refrigerant circuit at least including a compressor (51), an evaporator (50), a condenser (52), and a control device (55), characterized in that propane is contained as a refrigerant in the refrigerant circuit, with a filling capacity of between 300 g and 1500 g the refrigerant circuit has a low-pressure region with an operating pressure of between 0.8 and 2.0 bar and a high-pressure region with an operating pressure of between 20 and 30 bar; the compressor (51) and the condenser (52) are positioned spaced apart from each other, particularly in different wall groups; the evaporator (50) is positioned in the rear wall group (120); the compressor (51) is positioned beneath the evaporator (50) in a lower region of the rear wall group (12) and at least one fan (56) for assisting a flow of cooling air is positioned above the evaporator (50) in the rear wall group (12); the at least one fan (56, 57) has a motor over temperature protection; the cooling device (5) in the refrigerant circuit has a maximum surface temperature of less than 300° C. during operation; the compressor (51) is a hermetically sealed, suction-gas-cooled compressor, and the compressor (51) is situated in a lowest region of the refrigerant circuit in terms of geodetic altitude. ### Claim 2 (depends on 1) The refrigerated display case (1) according to claim 1, characterized in that the propane is contained as the refrigerant in the refrigerant circuit, with a filling capacity between 500 g and 900 g. ### Claim 3 (depends on 1) The refrigerated display case (1) according to claim 1, characterized in that the control device (55) is mounted to the top group (13), wherein in response to the control device (55) being mounted in the top group (13), the control device (55) is protectively enclosed in a housing. ### Claim 4 (depends on 1) The refrigerated display case (1) according to claim 1, characterized in that at least a portion of electrical components of a plurality of the electrical components used in the refrigerated display case (1) is provided with spark suppression. ### Claim 5 (depends on 4) The refrigerated display case (1) according to claim 4, characterized in that at least one safety relay is provided in a main circuit of the refrigerated display case (1), the at least a portion of electrical components of the plurality of the electrical components is provided with a spark-suppressing coating, conductor track spacings of high-voltage lines are at least 3 mm, spark-preventing plug connections are used. ### Claim 6 (depends on 1) The refrigerated display case (1) according to claim 1, characterized in that the evaporator (50) has a heat transmission device (65) with aluminum fins and/or copper tubes that have an inner diameter of between 10 mm and 15 mm and/or a maximum volume of between 3 l and 7 l. ### Claim 7 (depends on 1) The refrigerated display case (1) according to claim 1, characterized in that the condenser (51) includes a plate heat exchanger that operates in accordance with a counterflow principle, on whose warm side a flow rate of the propane is up to 100 kg/h, and on whose cold side a glycol/water mixture is used as a coolant in a secondary circuit. ### Claim 8 (depends on 1) The refrigerated display case (1) according to claim 1, characterized in that the refrigerated display case (1) includes at least two display case modules (1.1, 1.2, 1.3), which are arranged in a row with each other and are composed of module frames, with side frames (10) that have frame profiles and that support the bottom group (11), the rear wall group (12), and the top group (13) with respective casing parts and the display case modules (1.1, 1.2, 1.3) are provided with a shared evaporator (50′) that is positioned in the rear wall group and extends across a plurality of the at least two display case modules (1.1, 1.2, 1.3). ### Claim 9 (depends on 1) The refrigerated display case (1) according to claim 1, characterized in that side frames (10) are C-shaped when viewed from the side. ### Claim 10 (depends on 1) The refrigerated display case (1) according to claim 1, characterized in that a front roller shade (63) that is operated by a roller shade motor is accommodated in the front section of the top group (13) and the roller shade motor has a spark-preventing design and/or is accommodated in a protective encapsulation. ### Claim 11 (depends on 2) The refrigerated display case (1) according to claim 2, characterized in that the refrigerant circuit has a low-pressure region with an operating pressure of between 0.8 and 2.0 bar and a high-pressure region with an operating pressure of between 20 and 30 bar. ### Claim 12 (depends on 4) The refrigerated display case (1) according to claim 4, characterized in that at least one safety relay is provided in a main circuit of the refrigerated display case (1), the at least a portion of electrical components of the plurality of the electrical components is provided with a spark-suppressing coating, conductor track spacings of high-voltage lines are at least 3 mm, or spark-preventing plug connections are used. ### Claim 13 A refrigerated display case (1) with at least one unit composed of a plurality of wall groups, namely a bottom group (11), a rear wall group (12), and a top group (13), which delimit a refrigerated chamber (4) at a bottom, at a back, and at a top, and with a cooling device (5) that has a refrigerant circuit at least including a compressor (51), an evaporator (50), a condenser (52), and a control device (55), characterized in that propane is contained as a refrigerant in the refrigerant circuit, with a filling capacity of between 300 g and 1500 g.