JPH028258B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for testing the thermal insulation performance of a thermos flask.

[Prior art and its problems]

Generally, thermos flasks are made up of double inner and outer cylinders, and a heat insulating layer is formed between the inner and outer cylinders using a vacuum or other heat insulation treatment. The product has been commercialized through a vacuum treatment process that seals the product, a cleaning process that cleans the inside of the thermos flask and dries it with high-temperature dry gas, and an inspection process that measures insulation performance and checks for defective products. It's normal. Among these, the inspection process to measure insulation performance is usually performed by filling or enclosing hot water or heated steam inside and determining the degree of temperature drop over time, or by heating from the outside with the mouth sealed, and by heating the internal atmosphere over time. Judgment is made based on the degree of increase in However, methods that use hot water or heated steam require a process of injecting and discharging the hot water or steam as well as drying the interior, and the method measures the temperature difference by the natural fall of the hot water or heated steam due to the outside temperature. Therefore, the inspection takes a long time and the equipment is complicated and large. In addition, the method of heating the outside does not use hot water or steam, so the drying process after the inspection can be omitted, but since the method measures the degree of rise in the atmospheric temperature inside the thermos, the inconvenience of requiring a long time for the inspection cannot be avoided. .

Also, as shown in Japanese Patent Application Laid-open No. 49-67680,
There is a method of testing insulation performance by injecting hot air into the bottle while transporting the thermos flask by suspending it upside down on a trolley conveyor. After measuring the initial temperature, it is led to a constant temperature room, and after about 15 minutes, it is transferred from the constant temperature room to a temperature control room, where the temperature is further measured and the insulation performance is inspected by the temperature change from the initial temperature. Because of this, it takes a long time to perform the test and requires separate hot air for the test.

Based on the above, the present inventors have studied various ways to improve the insulation performance testing method, and as a result, they have found that the measurement time can be significantly shortened by a completely different measurement method from the conventional measurement method, and the manufacturing process described above. It has been discovered that the cleaning process and the inspection process in the manufacturing process can be organically combined, and that this combination can streamline the manufacturing process and reduce the heat source.

[Objects and means of the present invention]

The present invention aims to provide a method for inspecting the thermal insulation performance of a thermos flask, which streamlines the manufacturing process and shortens inspection time by utilizing the high-temperature drying gas used for the drying process in the washing process for the inspection process. This is the purpose.

In the method of the present invention, a thermos flask consisting of an inner and outer cylinder with a heat insulating layer formed between the inner and outer cylinders is placed upside down on a belt conveyor with the mouth of the flask aligned with the opening of the belt conveyor, and the washing process is carried out. , the inside of the thermos bottle is washed during the transfer, and then high-temperature dry gas is supplied into the thermos bottle to dry the inside of the thermos bottle, and before the drying process with the high-temperature dry gas starts (before the start of high-temperature dry gas supply), Measure the initial temperature of the thermos barrel during the drying process (while supplying high-temperature drying gas) or immediately after the end of the drying process (immediately after stopping the supply of high-temperature drying gas), and also measure the initial temperature after starting the supply of high-temperature drying gas. This method is characterized by measuring the rising temperature of the outer barrel of the thermos flask after a certain period of time has elapsed since the measurement, including the end point of the temperature rise, and inspecting the heat insulation performance based on the temperature change between the two measured temperatures.

〔Example〕

Hereinafter, one embodiment of the method of the present invention will be described in detail.

In Fig. 1, 1A, 1B, and 1C are thermos bottles that have undergone an assembly process and a vacuum treatment process, respectively, and are composed of an inner and outer cylinder 2 and an outer cylinder 3, and are vacuum insulated between the inner and outer cylinders 2 and 3. The vacuum flasks 1A, 1B, and 1C are placed upside down on the belt conveyor 4 with the mouths of the thermos flasks 1A, 1B, and 1C aligned with the respective openings of the belt conveyor 4, and transported to the washing process. The thermos 1A is washed by a high-pressure washer 5 by spraying a washing liquid into the bottle, and the thermos 1B is washed with the washing liquid and then the inside of the bottle is washed with water by a water washer 6. The thermos flask 1C that has been washed with water is sent through the supply pipe 7, and is dried by supplying high-temperature drying gas injected from the nozzle 8 into the bottle.

The above is a washing process that is normally carried out, and conventionally, after the washing process is completed, the process moves to the above-mentioned step of inspecting the heat insulation performance using hot water, etc., but the method of the present invention is carried out during the above-mentioned washing process. That is, after washing with water by the water washer 6 and before starting the drying process, that is, before starting the supply of high-temperature drying gas, the initial temperature T ₁ is measured by touching the measurement sensor 9 at an arbitrary measurement point of the thermos bottle outer cylinder 3, for example, on the bottom wall. do. Next, a high temperature drying gas is supplied into the bottle to perform a drying process, and after a certain period of time has elapsed since the start of drying, the temperature T ₂ at the measurement point is measured while the temperature is rising (including the end point of temperature rise),
The temperature difference between these (ΔT=T ₂ −T ₁ ) is determined, and the quality is judged based on the obtained ΔT. In this case, the temperature may be measured by measuring the initial temperature T ₁ during the washing step before the start of the drying process, for example during washing with water, or
Furthermore, the temperature T ₂ can be measured during the drying process or even after a certain period of time has passed after the drying process is completed, while the temperature of the outer cylinder is rising due to residual heat, or at the end of the rise. Furthermore, the temperature T ₁ is measured during the drying process or immediately after the drying process is finished, and after a certain period of time has passed, the temperature T ₂ during the rise (including the end point of temperature rise) is measured and the temperature difference is calculated from T ₁ - _{T 2} . It is also possible.

Figure 2 is an example measurement diagram of a metal thermos flask with an inner volume of ₁ and both the inner and outer tanks made of stainless steel.
This figure shows the temperature change obtained by drying with dry air. Solid line a in the figure is ΔT
The dotted line b indicates a defective product with poor insulation performance, and the dotted line _b indicates a defective product with poor insulation performance.
It was confirmed that approximately 2 minutes is sufficient for T ₂ measurement.

〔Effect of the invention〕

As described above, the present invention transports a thermos bottle placed upside down on a belt conveyor to a washing process, washes the inside of the bottle during the transfer, and then supplies high-temperature drying gas to the inside of the bottle to dry the inside of the bottle. Measure the initial temperature of the thermos barrel before the start of the drying process, during the drying process, or immediately after the end of the drying process, and also while the temperature of the thermos barrel is rising after the high temperature drying gas supply has started and a certain period of time has passed after the initial temperature measurement. (including the end point of temperature rise), and the insulation performance is inspected based on the temperature change at both measured temperatures, so the high temperature dry gas used for the drying process after washing, which was previously required, can be used to improve the insulation performance. Since it is used as a heat source for inspection, hot water, heated steam, hot air, etc. used only for inspection can be omitted, and the inspection process can be incorporated into the cleaning process, thereby streamlining the process. In addition, conventionally, measurements were made by determining the temperature change of hot water, heated steam, or atmospheric gas poured into a thermos flask, but the present invention allows for direct measurement of the heat transmitted through the thermos insulation layer of a thermos flask, resulting in faster response. For example, according to the conventional testing method using hot water, it takes at least 3 minutes to obtain the temperature difference ΔT, and it takes time to pour and drain the hot water, but according to the method of the present invention, It is sufficient to use a high-temperature drying gas of about 2 minutes after the start of drying.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of the method of the present invention, and FIG.
The figure is an example measurement diagram in the case of a metal thermos flask having an inner capacity of 1 and both the inner and outer tanks made of stainless steel as the test object. 1A, 1B, 1C...Thermos bottle consisting of inner cylinder 2 and outer cylinder 3, 5...High pressure washer, 6...Water washer, 7...
... Supply pipe, 8 ... Nozzle, 9 ... Measurement sensor.

Claims (1)

[Claims] 1. A thermos bottle, which has double inner and outer cylinders and a heat insulating layer is formed between the inner and outer cylinders, is transferred to the washing process by placing the thermos bottle upside down on the belt conveyor with its mouth aligned with the opening of the belt conveyor. The inside of the thermos bottle is washed during the transfer, and then high-temperature dry gas is supplied into the thermos bottle to dry the inside of the thermos bottle, and the outer cylinder of the thermos bottle is cleaned before, during, or immediately after the drying process using the high-temperature dry gas. Measure the initial temperature, and then measure the temperature during the rise, including the end point of temperature rise, of the thermos outer cylinder after the start of supply of high-temperature dry gas and after a certain period of time has passed after the initial temperature measurement. A method for inspecting the thermal insulation performance of a thermos flask, characterized by inspecting the performance.