# US 9,775,448 B2 · Refrigerated display appliances > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,775,448 B2 - Document ID: US9775448B2 - Status: Granted - Kind: B2 - Application number: 15/000,520 - Filed: 2016-01-19 - Published: 2016-05-12 - Granted: 2017-10-03 - Earliest claimed: 2010-03-29 - Assignees: Applied Design and Engineering Limited - Applicants: Applied Design and Engineering Ltd. - Inventors: Ian Wood; Edward Hammond - Web page: https://patentgrep.com/patent/US9775448B2 ## CPC - A47F 3/0447: {with air curtains} - A47F 3/0478: {Control or safety arrangements} - A47F 2003/046: {with shelves having air ducts} - A47F: SPECIAL FURNITURE, FITTINGS, OR ACCESSORIES FOR SHOPS, STOREHOUSES, BARS, RESTAURANTS OR THE LIKE; PAYING COUNTERS ## Abstract A refrigerated display unit having an open-fronted cabinet providing a product display space accessible through an access opening provided by the open front. Cooling means produces cold air to refrigerate items in the product display space. A cold air curtain is provided across the access opening using a forwardly-positioned discharge outlet communicating with a supply duct and a forwardly-positioned return inlet in communication with a return duct receiving air from the air curtain. The air curtain is substantially unsupported by the any supplementary cooling airflow supplied into the product display space separately from the air curtain. ## Claims ### Claim 1 A refrigerated display unit, comprising: an open-fronted cabinet containing a product display space accessible through an access opening defined by the open front; a cooling means for introducing or producing cold air to refrigerate items in the product display space in use; at least one forwardly-positioned discharge outlet communicating with a supply duct for, in use, projecting cold air with a discharge velocity as an air curtain across the access opening, which discharge outlet has an effective width that determines air curtain thickness; and at least one forwardly-positioned return inlet communicating with a return duct for, in use, receiving air from the air curtain, such that spacing between the discharge outlet and the return inlet determines air curtain height; wherein the discharge velocity, as measured at a point 25 mm below the discharge outlet, is between 0.1 m/s and 1.5 m/s; air curtain height is less than ten times the air curtain thickness; and the air curtain is substantially unsupported by any supplementary cooling airflow supplied into the product display space separately from the air curtain. ### Claim 2 (depends on 1) The unit of claim 1, wherein the mass flow rate of any supplementary cooling airflow is less than 5% of the mass flow rate of the cold air projected from the discharge outlet to form the air curtain. ### Claim 3 (depends on 1) The unit of claim 1, wherein substantially no supplementary cooling airflow is supplied into the product display space. ### Claim 4 (depends on 1) The unit of claim 1, wherein any supplementary cooling airflow is supplied into the product display space substantially only at a location spaced between the access opening and a back inner panel of the product display space. ### Claim 5 (depends on 4) The unit of claim 4, wherein supplementary cooling airflow is supplied in the region of a side inner panel of the product display space. ### Claim 6 (depends on 5) The unit of claim 5, wherein supplementary cooling airflow is supplied from a shelf in the cabinet. ### Claim 7 (depends on 1) The unit of claim 1, wherein the supply duct and the return duct together extend around the product display space to define a recirculation path between the return inlet and the discharge outlet. ### Claim 8 (depends on 7) The unit of claim 7, wherein the supply duct and the return duct lie behind inner panels that define the product display space, to provide supplementary cooling to the product display space by cooling the inner panels. ### Claim 9 (depends on 8) The unit of claim 8, wherein at least one inner panel is at least partially insulated, heated or of low conductivity to reduce local supplementary cooling to the product display space. ### Claim 10 (depends on 1) The unit of claim 1 and comprising at least one finisher extending laterally in front of the discharge outlet and/or the return inlet, the or each finisher being insulated, heated, of low-conductivity material and/or with a low-emissivity finish. ### Claim 11 (depends on 10) The unit of claim 10, wherein at least one finisher influences airflow discharged from the discharge outlet or received by the return inlet. ### Claim 12 (depends on 11) The unit of claim 11 wherein a finisher in front of the discharge outlet has a lower edge that lies below a discharge face of the discharge outlet. ### Claim 13 (depends on 11) The unit of claim 11, wherein a finisher in front of the return inlet has an upper portion that extends above an intake face of the return inlet. ### Claim 14 (depends on 13) The unit of claim 13, wherein the upper portion of that finisher is inclined upwardly and forwardly away from the product display space. ### Claim 15 (depends on 13) The unit of claim 13, and having an upstanding riser on a rear side of the return inlet. ### Claim 16 (depends on 15) The unit of claim 15, wherein the riser and the opposed upper portion of the finisher cooperate to channel air from the air curtain into the return inlet. ### Claim 17 (depends on 13) The unit of claim 13, wherein the upper portion of that finisher is inclined upwardly and rearwardly toward the product display space. ### Claim 18 (depends on 1) The unit of claim 1, and being adapted to generate a velocity profile that varies across the thickness of the air curtain, with faster airflow on the side of the curtain facing the product display space. ### Claim 19 (depends on 1) The unit of claim 1, further comprising upright finishers that are disposed in front of the air curtain along sides of the air curtain and extend inwardly across the access opening. ### Claim 20 (depends on 1) The unit of claim 1, further comprising a differential pressure sensor arranged to compare pressures in the supply and return duct; and a controller responsive to a signal from the sensor to control the unit in accordance with the signal to modify relative pressures in the ducts. ### Claim 21 (depends on 1) The unit of claim 1, comprising: an open-fronted cabinet defining a cold-storage volume; and at least one shelf disposed in the cold-storage volume for supporting refrigerated items in use; wherein the shelf defines an upper access opening above the shelf and a lower access opening below the shelf affording access to refrigerated items in respective product display spaces in the cold-storage volume above and below the shelf, and the shelf has: at least one forwardly-positioned discharge outlet communicating with a supply duct for, in use, projecting cold air as an air curtain across the lower access opening; and at least one forwardly-positioned return inlet communicating with a return duct for, in use, receiving air from another air curtain discharged above the shelf across the upper access opening. ### Claim 22 (depends on 21) The unit of claim 21, wherein the shelves are arranged in a vertical array and a plurality of vertical arrays of shelves are arranged into side-by-side columns. ### Claim 23 (depends on 22) The unit of claim 22, and comprising at least one partition between shelves of adjacent columns. ### Claim 24 (depends on 23) The unit of claim 23, wherein at least a front edge of the partition is insulated, heated, of low-conductivity material and/or with a low-emissivity finish. ### Claim 25 (depends on 21) The unit of claim 21, wherein the or each shelf is bounded to the sides by at least one partition and/or by at least one side wall of the cabinet, and wherein the partition or side wall extends forwardly beyond the shelf. ### Claim 26 (depends on 25) The unit of claim 25, wherein a finisher that is insulated, heated, of low-conductivity material and/or with a low-emissivity finish on front of the shelf extends from the partition or side wall on one side of the shelf to the partition or side wall on the other side of the shelf. ### Claim 27 (depends on 1) The unit of claim 1, wherein a front-to-rear thickness of the air curtain is between 40 mm and 250 mm. ### Claim 28 (depends on 1) The unit of claim 1, wherein a vertical height of the air curtain is between 200 mm and 800 mm.