Defrosting in open show case of cold-air-circulation type

Claim 2

In the defrosting of an open show case of cold-air-circulation type having: a case structure including an outer cabinet and a cooled commodity box disposed in the innermost part of said cabinet and adapted to hold commodities in cooled state, said case structure having a front opening for access from the outside to said commodities; a cold-air-circulation passage means formed adjacently around said box and provided therewithin with air cooling means and first air circulation means for circulating cold air through said passage means, said passage means having, at respectively opposite ends thereof and at opposite upper and lower sides of said access opening, ejection nozzle means and corresponding suction inlet means between which a cold-air curtain is formed when air is thus circulated in normal cooling operation; and air passage means provided with second air circulation means and having air ejection nozzle means and corresponding suction inlet means for forming at least one protective air curtain outside of said cold-air curtain for shielding said cold-air curtain from the outside air, an improved defrosting method which comprises controllably stopping the operation of said air cooling means and operating said first and second air circulation means respectively in mutually adjacent air passage means to circulate air in mutually opposite directions thereby to cause air to flow in short-circuited flow at said ejection nozzle means and suction inlet means, in which flow, air ejected from one passage means is immediately sucked into an adjacent passage means without forming an air curtain across the access opening, thereby to draw warm outside air into said cold-air-circulation passage means, and thereby to melt and remove frost adhering to parts related to said passage means.

Claim 3

In the defrosting of an open show case of cold-air-circulation type having: a case structure including an outer cabinet and a cooled commodity box disposed in the innermost part of said cabinet and adapted to hold commodities in cooled state, said case structure having a front opening for access from the outside to said commodities; a first passage formed adjacently outside of and around said box and provided therewithin with air cooling means and first air circulation means for circulating cold air through said passage, said passage having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet between which a cold-air curtain is formed when cold air is thus circulated in normal cooling operation; a second passage provided with second air circulation means and having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet for forming a protective second air curtain outside of said cold-air curtain; and a third air passage provided with third air circulation means and having at one end thereof an opening communicating with the outside air and at the other end thereof an ejection nozzle for blowing a protective third air curtain outside of said second air curtain, an improved defrosting method which comprises controllably stopping the operation of said air cooling means, operating said second air circulation means in the same forward direction as in said normal cooling operation, and operating said first and third air circulation means in respective directions reverse to those in normal cooling operation thereby to cause a portion of air in said first passage to flow out of said suction inlet thereof and be immediately sucked in short-circuited flow into said suction inlet of said second passage and portions of air in said second passage to flow out of said ejection nozzle thereof and be immediately sucked in short-circuited flow into said ejection nozzles of said first and third passages and thereby to draw warm outside air into said passages to accomplish defrosting.

Claim 4

In the defrosting of an open show case of cold-air-circulation type having: a case structure including an outer cabinet and a cooled commodity box disposed in the innermost part of said cabinet and adapted to hold commodities in cooled state, said case structure having a front opening for access from the outside to said commodities; a first passage formed adjacently outside of and around said box and provided therewithin with air cooling means and first air circulation means for circulating cold air through said passage, said passage having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet between which a cold-air curtain is formed when cold air is thus circulated in normal cooling operation; a second passage provided with second air circulation means and having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet for forming a protective second air curtain outside of said cold-air curtain; and a third air passage provided with third air circulation means and having at one end thereof an opening communicating with the outside air and at the other end thereof an ejection nozzle for blowing a protective third air curtain outside of said second air curtain, an improved defrosting method which comprises controllably stopping the operation of said air cooling means, operating said second air circulation means in the same forward direction as in said normal cooling operation, and operating said first and third air circulation means in respective directions reverse to those in normal cooling operation thereby to cause a portion of air in said first passage to flow out of said suction inlet thereof and be immediately sucked in short-circuited flow into said suction inlet of said second passage and portions of air in said second passage to flow out of said ejection nozzle thereof and be immediately sucked in short-circuited flow into said ejection nozzles of said first and third passages and thereby to draw warm outside air into said passages to accomplish defrosting.

Claim 5

In the defrosting of an open show case of cold-air-circulation type having: a case structure including an outer cabinet and a cooled commodity box disposed in the innermost part of said cabinet and adapted to hold commodities in cooled state, said case structure having a front opening for access from the outside to said commodities; a first passage formed adjacently outside of and around said box and provided therewithin with air cooling means and first air circulation means for circulating cold air through said passage, said passage having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet between which a cold-air curtain is formed when cold air is thus circulated in normal cooling operation; a second passage provided with second air circulation means and having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet for forming a protective second air curtain outside of said cold-air curtain; and a third air passage provided with third air circulation means and having at one end thereof an opening communicating with the outside air and at the other end thereof an ejection nozzle for blowing a protective third air curtain outside of said second air curtain, an improved defrosting method which comprises controllably stopping the operation of said air cooling means, operating the first and third air circulation means in the same forward directions as in said normal cooling operation, and operating said second air circulation means in the direction reverse to that in normal cooling operation thereby to cause a portion of air in said second passage to flow out of said suction inlet thereof and be immediately sucked in short-circuited flow into said suction inlet of said first passage and portions of air in said first and third passages to flow out of respective ejection nozzles thereof and be immediately sucked in short-circuited flow into said ejection nozzle of said second passage and thereby to draw warm outside air into said passages to accomplish defrosting.

Claim 6

In the defrosting of an open show case of cold-air-circulation type having: a case structure including an outer cabinet and a cooled commodity box disposed in the innermost part of said cabinet and adapted to hold commodities in cooled state, said case structure having a front opening for access from the outside to said commodities; a first passage formed adjacently outside of and around said box and provided therewithin with air cooling means and first air circulation means for circulating cold air through said passage, said passage having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet between which a cold-air curtain is formed when cold air is thus circulated in normal cooling operation; a second passage provided with second air circulation means and having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet for forming a protective second air curtain outside of said cold-air curtain; and a third air passage provided with third air circulation means and having at one end thereof an opening communicating with the outside air and at the other end thereof an ejection nozzle for blowing a protective third air curtain outside of said second air curtain, an improved defrosting method which comprises controllably stopping the operation of said air cooling means, operating the first and third air circulation means in the same forward directions as in said normal cooling operation, and operating said second air circulation means in the direction reverse to that in normal cooling operation thereby to cause a portion of air in said second passage to flow out of said suction inlet thereof and be immediately sucked in short-circuited flow into said suction inlet of said first passage and portions of air in said first and third passages to flow out of respective ejection nozzles thereof and be immediately sucked in short-circuited flow into said ejection nozzle of said second passage and thereby to draw warm outside air into said passages to accomplish defrosting.

Claim 7

In an open show case of cold-air-circulation type having: a case structure including an outer cabinet and a cooled commodity box disposed in the innermost part of said cabinet and adapted to hold commodities in cooled state, said case structure having a front opening for access from the outside to said commodities; a cold-air-circulation passage means formed adjacently around said box and provided therewithin with air cooling means and first air circulation means for circulating cold air through said passage means, said passage means having at respectively opposite ends thereof, and at opposite sides of said access opening, ejection nozzle means and corresponding suction inlet means between which a cold-air curtain is formed when air is thus circulated in normal cooling operation; and air passage means provided with second air circulation means and having air ejection nozzle means and corresponding suction inlet means for forming at least one protective air curtain outside of said cold-air curtain for shielding said cold-air curtain from the outside air, the improvement wherein the air circulation means in at least one of said passage means is reversible in air circulating direction, and wherein there is provided means operable at the time of defrosting of the show case to stop the operation of said air cooling means and operating said first and second air circulation means respectively in mutually adjacent air passage means to circulate air in mutually opposite directions thereby to cause air to flow in short-circuited flow at said ejection nozzle means and suction inlet means, in which flow, air ejected from one passage means is immediately sucked into an adjacent passage means without forming an air curtain across the access opening, thereby to draw warm outside air into said passage means and thereby to accomplish defrosting.

Claim 8

In an open show case of cold-air-circulation type having: a case structure including an outer cabinet and a cooled commodity box disposed in the innermost part of said cabinet and adapted to hold commodities in cooled state, said case structure having a front opening for access from the outside to said commodities; a cold-air-circulation passage means formed adjacently around said box and provided therewithin with air cooling means and first air circulation means for circulating cold air through said passage means, said passage means having at respectively opposite ends thereof, and at opposite sides of said access opening, ejection nozzle means and corresponding suction inlet means between which a cold-air curtain is formed when air is thus circulated in normal cooling operation; and air passage means provided with second air circulation means and having air ejection nozzle means and corresponding suction inlet means for forming at least one protective air curtain outside of said cold-air curtain for shielding said cold-air curtain from the outside air, the improvement wherein the air circulation means in at least one of said passage means is reversible in air circulating direction, and wherein there is provided means operable at the time of defrosting of the show case to stop the operation of said air cooling means and operating said first and second air circulation means respectively in mutually adjacent air passage means to circulate air in mutually opposite directions thereby to cause air to flow in short-circuited flow at said ejection nozzle means and suction inlet means, in which flow, air ejected from one passage means is immediately sucked into an adjacent passage means without forming an air curtain across the access opening, thereby to draw warm outside air into said passage means and thereby to accomplish defrosting.

Claim 9

In an open show case of cold-air-circulation type having: a case structure including an outer cabinet and a cooled commodity box disposed in the innermost part of said cabinet and adapted to hold commodities in cooled state, said case structure having a front opening for access from the outside to said commodities; a first passage formed adjacently outside of and around said box and provided therewithin with air cooling means and first air circulation means for circulating cold air through said passage, said passage having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet between which a cold-air curtain is formed when cold air is thus circulated in normal cooling operation; a second passage provided with second air circulation means and having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet for forming a protective second air curtain outside of said cold-air curtain; and a third air passage provided with third air circulation means and having at one end thereof an opening communicating with the outside air and at the other end thereof an ejection nozzle for blowing a protective third air curtain outside of said second air curtain, the improvement wherein said first and third air circulation means are reversible in respective air circulations directions thereof, and wherein there is provided means operable at the time of defrosting of the show case to stop the operation of said air cooling means, operating said second air circulation means in the same forward direction as in said normal cooling operation, and operating said first and third air circulation means in respective directions reverse to those in normal cooling operation thereby to cause a portion of air in said first passage to flow out of said suction inlet thereof and be immediately sucked in short-circuited flow into said suction inlet of said second passage and portions of air in said second passage to flow out of said ejection nozzle thereof and be immediately sucked in short-circuited flow into said ejection nozzles of said first and third passages and thereby to draw warm outside air into said passages to accomplish defrosting.

Claim 10

In an open show case of cold-air-circulation type having: a case structure including an outer cabinet and a cooled commodity box disposed in the innermost part of said cabinet and adapted to hold commodities in cooled state, said case structure having a front opening for access from the outside to said commodities; a first passage formed adjacently outside of and around said box and provided therewithin with air cooling means and first air circulation means for circulating cold air through said passage, said passage having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet between which a cold-air curtain is formed when cold air is thus circulated in normal cooling operation; a second passage provided with second air circulation means and having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet for forming a protective second air curtain outside of said cold-air curtain; and a third air passage provided with third air circulation means and having at one end thereof an opening communicating with the outside air and at the other end thereof an ejection nozzle for blowing a protective third air curtain outside of said second air curtain, the improvement wherein said first and third air circulation means are reversible in respective air circulations directions thereof, and wherein there is provided means operable at the time of defrosting of the show case to stop the operation of said air cooling means, operating said second air circulation means in the same forward direction as in said normal cooling operation, and operating said first and third air circulation means in respective directions reverse to those in normal cooling operation thereby to cause a portion of air in said first passage to flow out of said suction inlet thereof and be immediately sucked in short-circuited flow into said suction inlet of said second passage and portions of air in said second passage to flow out of said ejection nozzle thereof and be immediately sucked in short-circuited flow into said ejection nozzles of said first and third passages and thereby to draw warm outside air into said passages to accomplish defrosting.

Claim 11

In an open show case of cold-air-circulation type having: a case structure including an outer cabinet and a cooled commodity box disposed in the innermost part of said cabinet and adapted to hold commodities in cooled state, said case structure having a front opening for access from the outside to said commodities; a first passage formed adjacently outside of and around said box and provided therewithin with air cooling means and first air circulation means for circulating cold air through said passage, said passage having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet between which a cold-air curtain is formed when cold air is thus circulated in normal cooling operation; a second passage provided with second air circulation means and having, at respectively opposite ends thereof at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet for forming a protective second air curtain outside of said cold-air curtain; and a third air passage provided with third air circulation means and having at one end thereof an opening communicating with the outside air and at the other end thereof an ejection nozzle for blowing a protective third air curtain outside of said second air curtain, the improvement wherein said second air circulation means is reversible in the air circulation direction thereof, and wherein there is provided means operable at the time of defrosting of the show case to stop the operation of said air cooling means, operating the first and third air circulation means in the same forward directions as in said normal cooling operation, and operating said second air circulation means in the direction reverse to that in normal cooling operation thereby to cause a portion of air in said second passage to flow out of said suction inlet thereof and be immediately sucked in short-circuited flow into said suction inlet of said first passage and portions of air in said first and third passages to flow out of respective ejection nozzles thereof and be immediately sucked in short-circuited flow into said ejection nozzle of said second passage and thereby to draw warm outside air into said passages to accomplish defrosting.

Claim 12

In an open show case of cold-air-circulation type having: a case structure including an outer cabinet and a cooled commodity box disposed in the innermost part of said cabinet and adapted to hold commodities in cooled state, said case structure having a front opening for access from the outside to said commodities; a first passage formed adjacently outside of and around said box and provided therewithin with air cooling means and first air circulation means for circulating cold air through said passage, said passage having, at respectively opposite ends thereof and at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet between which a cold-air curtain is formed when cold air is thus circulated in normal cooling operation; a second passage provided with second air circulation means and having, at respectively opposite ends thereof at opposite sides of said access opening, an ejection nozzle and a corresponding suction inlet for forming a protective second air curtain outside of said cold-air curtain; and a third air passage provided with third air circulation means and having at one end thereof an opening communicating with the outside air and at the other end thereof an ejection nozzle for blowing a protective third air curtain outside of said second air curtain, the improvement wherein said second air circulation means is reversible in the air circulation direction thereof, and wherein there is provided means operable at the time of defrosting of the show case to stop the operation of said air cooling means, operating the first and third air circulation means in the same forward directions as in said normal cooling operation, and operating said second air circulation means in the direction reverse to that in normal cooling operation thereby to cause a portion of air in said second passage to flow out of said suction inlet thereof and be immediately sucked in short-circuited flow into said suction inlet of said first passage and portions of air in said first and third passages to flow out of respective ejection nozzles thereof and be immediately sucked in short-circuited flow into said ejection nozzle of said second passage and thereby to draw warm outside air into said passages to accomplish defrosting.