JP2012189425A - Measuring apparatus for element adsorption/desorption amount - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a measuring apparatus for element adsorption/desorption amount, having a balance which is capable of performing accurate measuring at all the time without being thermally influenced by a heater which heats a corrosive gas or an object to be measured.SOLUTION: A measuring apparatus for an element adsorption/desorption amount is configured to measure the amount of elements adsorbed to an object to be measured or the amount of elements desorbed from the object to be measured. The measuring apparatus comprises a balance 25 which measures the weight of the object to be measured, a tray 34 which is arranged to be positioned lower than the balance and in which the object to be measured is placed, a connection member 26 which connects the balance and the tray, a first container 21 which accommodates the balance therein, a second container 22 which accommodates the tray therein and includes a heating source for heating the object to be measured, a thermal shield plate 24 which shields the balance in the first container from heat of the heating source, and an exhaust mechanism which introduces a gas from a lower portion of the second container into the container and exhausts the gas from the upper portion thereof.

Description

  The present invention relates to an element adsorption / desorption amount measuring apparatus for measuring the amount of an element adsorbed on an object to be measured or the amount of an element desorbed from the object to be measured.

  As is well known, for example, if a gas element is present in various metal parts such as automobiles, the mechanical strength of the metal part deteriorates, so it is necessary to measure in advance the amount of gas contained in the sample of the metal part. there were. For this reason, development of techniques for measuring the amount of gas in a sample has been in progress.

Patent document 1 is a technique regarding the apparatus which measures the weight of the evaporated substance condensed and deposited on the collection board. This technique will be described with reference to FIG.
This apparatus includes an evaporation source container 1 and a sealed container 2, and these containers are connected by a pipe section 3. In the evaporation source container 1, an evaporation source 4 for holding the evaporation substance M and a heater 5 are provided, and a collecting plate 6 is provided at a spaced position on the evaporation source 4. The collection plate 6 is suspended from a balance mechanism portion 8 provided in the sealed container 2 via a connecting rod 7 that passes through the piping portion 3. The balance mechanism unit 8 is placed on a pedestal 10 provided with a through hole 9 through which the connecting rod 7 is passed. An electric heater 11 is provided in the base 10 and is filled with a refrigerant 12 such as water.

  The signal terminal of the balance mechanism unit 8 is connected to the control power supply unit 15 via the signal wire 13 and a terminal 14 provided penetrating the sealed container 2. Further, the sealed container 2 is provided with an opening 16 for taking the balance mechanism unit 8 into and out of the sealed container 2. The opening 16 is closed by a lid 17. A vacuum pump 19 is connected to the evaporation source container 1 via a valve 18. Note that reference numerals 20 a and 20 b in the figure are fastening metal fittings for connecting the pipe portion 3 and the evaporation source container 1.

  In the apparatus having such a configuration, the weight of the evaporated substance M condensed and deposited on the collection plate 6 is measured by the following procedure. First, the valve 18 is opened, and the inside of the evaporation source container 1 and the sealed container 2 is brought into a predetermined vacuum state by the vacuum pump 19. Subsequently, the temperature of the base 10 is controlled and maintained at an optimum temperature for the operation of the balance mechanism unit 8. Thereafter, the balance mechanism unit 8 is actuated and controlled by the control power supply unit 15, and the total weight W0 of the collecting plate 6 and the connecting rod 7 in the vacuum state is measured and recorded in advance. Next, the heater 5 is energized. When heated, the evaporated substance M placed on the evaporation source 4 evaporates in the direction of the arrow, and condenses and accumulates on the lower surface of the collection plate 6. Therefore, the accumulated evaporation material M, the collection plate 6, and the connecting rod 7. The total weight W1 is measured and recorded in the same manner as described above. As a result, the film weight ΔW of the evaporation substance M can be regarded as ΔW = W1−W0.

Japanese Unexamined Patent Publication No. 7-19936

  By the way, in the conventional measuring apparatus, the balance mechanism unit 8 uses a control board on which electronic components such as semiconductor elements are mounted. Therefore, if corrosive gases such as chlorine and fluorine are present in the sealed container, There was a problem that the control board was easily corroded. Further, since the inside of the evaporation source container 1 is exposed to a high temperature atmosphere, the inside of the sealed container 2 communicating with the evaporation source container 1 and the piping unit 3 is also affected by thermal transition, and the control board in the balance mechanism unit 8 is adversely affected. There was a problem. Therefore, there is a problem that the weight of the film condensed and deposited on the lower surface of the collecting plate 6 cannot be accurately measured by the balance mechanism unit 8. Therefore, there has been a demand for an apparatus that is not affected by corrosive gas or thermal transition.

  The present invention has been made in consideration of such circumstances, and reduces the thermal effect of the heater that heats the corrosive gas and the object to be measured, thereby adsorbing and desorbing elements having a balance that enables accurate measurement. An object is to provide a measuring device for quantity.

  An element adsorption / desorption amount measuring apparatus according to the present invention is an element adsorption / desorption amount measurement apparatus for measuring the amount of an element adsorbed on a measured object or the amount of an element desorbed from the measured object. A balance for measuring the weight of the object to be measured; a receiving tray on which the object to be measured is placed; and a connecting member for connecting the balance and the receiving tray; A first container for storing a balance; a second container for storing the tray; and a heating source for heating an object to be measured; and the balance in the first container shielded from the heat of the heating source And a heat shield mechanism for introducing gas into the second container from the lower part of the container and exhausting the gas from the upper part.

  According to the present invention, it is possible to obtain an element adsorption / desorption amount measuring apparatus having a balance capable of reducing the thermal influence caused by a corrosive gas or a heater for heating an object to be measured and capable of accurate measurement. .

FIG. 1 is a schematic view of an apparatus for measuring the amount of adsorption / desorption of an element according to Example 1 of the present invention. FIG. 2 is a schematic view of an apparatus for measuring the amount of adsorption / desorption of elements according to Example 2 of the present invention. FIG. 3 is a schematic view of an element adsorption / desorption measuring apparatus according to Example 3 of the present invention. FIG. 4 is a schematic view of an element adsorption / desorption measuring apparatus according to Example 4 of the present invention. FIG. 5 is a schematic diagram of an apparatus for measuring the amount of adsorption / desorption of an element according to Example 5 of the present invention. FIG. 6 is a schematic view of an element adsorption / desorption measuring apparatus according to Example 6 of the present invention. FIG. 7 is an explanatory view of a conventional membrane weight measuring apparatus.

Hereinafter, an apparatus for measuring the amount of adsorption / desorption of elements according to the present invention will be described. However, the present invention is not limited to the embodiments described below.
Example 1
Reference is made to FIGS. 1 (A) and (B). Here, FIG. 1 (A) is a schematic diagram of an element adsorption / desorption amount measuring apparatus according to the first embodiment, and FIG. 1 (B) is an explanatory view showing an enlarged main part of FIG. 1 (A). is there. However, Example 1 shows an example in which the weight of the element desorbed from the object to be measured is measured.

  Reference numeral 21 in the figure denotes a sealed container (first container). A reaction container (second container) 22 is connected to the sealed container 21 via a connecting pipe 23 below the sealed container 21. A heat shield plate 24 for shielding heat from an electric heater, which will be described later, is provided in the sealed container 21, and is partitioned into a room 21 a separate from the room 21 a where the balance 25 is disposed.

  As shown in FIG. 1B, the heat shield plate 24 is annular and has a hollow portion 27b inside having a central hole 27a through which a wire (connecting member) 26 made of tungsten (W) or stainless steel (SUS304) is passed. A magnetic body 27, an annular permanent magnet 28 disposed in the hollow portion 27 b of the magnetic body 27, and an annular nonmagnetic body 29 disposed inside the permanent magnet 28 are provided. In the center hole 27a of the magnetic body 27, a magnetic fluid 30 that receives a magnetic action by the magnetic flux of the magnetic circuit formed by the magnetic body 27 and the permanent magnet 28 is disposed, and thereby the periphery of the wire 26 penetrating the center hole 27a. Is kept liquid-tight. Although not shown, a lid is provided on the top of the sealed container 21, and the inside of the chamber 21 a of the sealed container 21 is held at 1 atm so as to facilitate the exchange of the balance 25. A cooling mechanism 32 in which a coolant such as water 31 is accommodated is disposed around the sealed container 21 in order to cool the sealed container 21. Although not shown, the cooling mechanism 32 includes a supply pipe for supplying water, a discharge pipe, a pump, and the like.

Inside the reaction vessel 22, a receiving tray 34 made of Al ₂ O ₃ for placing an object 33 to be measured is provided. The tray 34 and the bottom of the balance 25 are connected by the wire 26. The inside of the reaction vessel 22 is heated to, for example, about 1500 ° C. by an electric heater 35 made of tungsten (W). A gas introduction pipe 36 for introducing a raw material gas (for example, a chemically reactive gas such as hydrogen or an inert gas) is connected to the lower side of the reaction vessel 22, and a gas discharge pipe 37 is connected to the upper side. Has been. The gas introduction pipe 36 and the discharge pipe 37 are provided with opening / closing valves 36a and 37a, respectively, which constitute an exhaust mechanism. The reaction vessel 22 is evacuated by a vacuum pump (not shown), but is omitted for convenience. In addition, a hole 22 (not shown) through which the wire 26 is passed is formed in the lid 22a constituting a part of the reaction vessel 22.

  When measuring the weight of the object to be measured 33 in the element adsorption / desorption measuring device having such a configuration, first, the inside of the reaction vessel 22 is evacuated, and then the source gas is opened with the open / close valves 36a and 37a opened. The measurement object 33 is heated by the electric heater 35 while exhausting the inside of the reaction vessel 22 from the discharge pipe 37 while introducing the gas from the gas introduction pipe 36. As a result, the element adsorbed on the object to be measured 33 interacts with the raw material gas and gradually desorbs, and the weight of the object to be measured 33 that gradually decreases can be measured.

  According to the first embodiment, the heat shield plate 24 for partitioning the inside of the sealed container into a room 21 a for accommodating the balance 25 and another room 21 b is provided in the sealed container 21, and the cooling mechanism 32 is provided around the sealed container 21. Therefore, it is possible to avoid the high temperature heat generated by the electric heater 35 that heats the measurement object 33 in the reaction vessel 22 from having a thermal effect on the balance 25 in the sealed vessel 21. Further, even if the object to be measured 33 contains corrosive gas, the balance 25 is protected by the heat shield plate 24 and the gas in the reaction vessel is exhausted from the exhaust mechanism. Therefore, the weight of the object to be measured 33 can always be accurately measured. Specifically, in the case of the first embodiment, it is possible to accurately measure that the element adsorbed on the measurement object 33 interacts with the raw material gas while being heated by the electric heater 35 and gradually desorbs. it can.

Further, since the exhaust mechanism is configured to supply the source gas from the bottom side of the reaction vessel 22 and discharge the gas from the upper side of the reaction vessel 22, the exhaust mechanism is generated by thermal decomposition of the source gas in the vicinity of the upper portion in the reaction vessel 22. It can be avoided that a light hydrogen layer remains and unreacted heavy gas remains at the bottom of the reaction vessel 22.
Further, in the first embodiment, the tray 34 is hung on the bottom side of the balance 25 using the wire 26 and the weight of the measurement object 33 placed on the tray 34 is measured. Therefore, the measurement object 33 has various shapes. Even if it does, there is little fluctuation | variation of the gravity center of the to-be-measured object 33, and the weight of the to-be-measured object 33 can be measured correctly.

(Example 2)
Please refer to FIG. Example 2 shows an example in which the weight of an element desorbed from a measurement object is measured. Note that the same members as those in FIG.
Reference numerals 41 and 42 in the figure are reaction vessels as a first vessel, and are communicated by a communication passage 43 positioned below. The reaction vessel 41 is partitioned into rooms 41 a and 41 b by the heat shield plate 24, and the reaction vessel 42 is partitioned into rooms 42 a and 42 b by the heat shield plate 24. A balance rod 44 made of Al ₂ O ₃ as a balance member is disposed in the communication path 43 and the rooms 41b and 42b.

  The bottom of one balance 25 and one end of the balance rod 44 are connected by a first wire 46, and the bottom of the other balance 25 and the other end of the balance rod 44 are connected by another first wire 47. In the chambers 41 b and 42 b where both ends of the balance bar 44 are located, stoppers 48 for reducing the rolling of the balance bar 44 are provided. The central portion of the balance bar 44 and the tray 34 are connected by a second wire 49.

  According to the second embodiment, the sealed containers 41 and 42 for respectively storing the balance 25 are arranged apart from each other by the communication passage 43, and the balance rod 44 is arranged in the communication passage 43 and the rooms 41b and 42b. 25 and the both ends of the balance rod 44 are connected by first wires 46 and 47, respectively, and the balance rod 44 and the tray 34 are connected by a second wire 49, so that the heat transfer path from the reaction vessel 22 As compared with the first embodiment, the thermal influence on the balance 25 in the high-temperature sealed containers 41 and 42 can be further reduced.

  Further, by arranging the stoppers 48 at both ends of the balance rod 44, the roll of the balance rod 44 can be suppressed. It should be noted that it is possible to avoid leaving a light hydrogen layer generated by thermal decomposition of the raw material gas near the top in the reaction vessel 22 or leaving unreacted heavy gas at the bottom of the reaction vessel 22 due to the presence of the exhaust mechanism. The same as in the case of Example 1.

(Example 3)
Please refer to FIG. Example 3 is an example in which the weight of an element desorbed from an object to be measured is measured. The same members as those in FIGS. 1 and 2 are denoted by the same reference numerals, and description thereof is omitted.
Reference numeral 51 in the figure denotes an inverted T-shape comprising a support shaft 51a, one end of which is fixed to the bottom of the tray 34, and a horizontal bar 51b connected to the lower end of the support shaft 51a so as to intersect the support shaft 51a. A mold member is shown. The wires 46 and 47 connect the bottom of each balance 25 and the end of the horizontal bar 51b, respectively. A connecting member is constituted by the inverted T-shaped member 51 and the wires 46 and 47. In Example 3, the connecting tube 23 is U-shaped, and the central portion of the U-shaped connecting tube 23 located on the lower side of the reaction vessel 22 is partially formed into a cylindrical chamber 23a having a large diameter. It has become. The stopper 48 is provided in a direction orthogonal to the axial direction of the support shaft 51 a of the inverted T-shaped member 51. Further, the heat shield plate 24 is disposed at the upper end portion of the connecting pipe 23.

  According to the third embodiment, the heat transfer path from the reaction vessel 22 is lengthened by the two wires 46 and 47 arranged in the U-shaped connecting pipe 23 and the inverted T-shaped member 51. Compared with Example 1, the thermal influence by the electric heater 35 in the reaction vessel 22 can be further suppressed. Even if the object to be measured 33 contains a corrosive gas, the gas supplied from the gas introduction pipe 36 to the lower side of the reaction vessel 22 passes through the discharge pipe 37 on the upper side of the reaction vessel 22 and is outside the reaction vessel. Almost all can be discharged. Therefore, the weight of the object to be measured 33 can always be accurately measured.

Example 4
Reference is made to FIGS. 4A and 4B. Here, FIG. 4A is a schematic view showing a cross section of the element adsorption / desorption amount measuring apparatus according to the fourth embodiment, and FIG. 4B is a plan view of the main part of FIG. 4A. . However, the same members as those in FIGS. 1 and 2 are denoted by the same reference numerals and description thereof is omitted. The fourth embodiment is characterized in that, for example, six balances 25 are arranged at equal intervals in the circumferential direction, and the weight range of the measurement object 33 that can be measured by each balance 25 is narrowed. In general, when the weight of the part to be measured is measured with one balance, the weight range of the object to be measured 33 that can be measured with the balance increases, and the weight measurement in smaller units becomes impossible. In the fourth embodiment, the weight of the object to be measured 33 can be measured with higher accuracy by using a large number of balances 25 and setting the weight range that can be measured by each balance 25 as a smaller unit.

(Example 5)
Please refer to FIG. However, the same members as those in FIGS. 1 and 2 are denoted by the same reference numerals and description thereof is omitted.
Reference numeral 52 in the figure is a cantilever beam. The cantilever 52 has one end (left end) fixed to the support shaft 52a so that one end is fixed to the bottom of the tray 34, and the other end (right end) communicates with the support shaft 52a. It consists of a plate-like member 52 b fixed to the inner wall of the chamber 55 below the tube 23. Here, the other end of the plate-like member 52b has a spring function, and the plate-like member 52b moves as indicated by an arrow A within the elastic deformation limit with the other end of the plate-like member 52b as a fulcrum P.

  One end of the wire 46 is connected to the bottom of the balance 25, and the other end is connected to the plate-like member 52b. The cantilever beam 52 and the wire 46 constitute a connecting member. A stopper 53 is provided on the lower side of the plate-like member 52b in order to stop the rapid downward movement of the plate-like member 52b.

  According to the fifth embodiment, similarly to the second embodiment, the thermal influence by the electric heater 35 in the reaction vessel 22 can be suppressed, and the measurement object 33 can be always measured with high accuracy, and the reaction vessel 22 can be measured. It can be smoothly discharged out of the reaction vessel without leaving any residual gas inside.

(Example 6)
Please refer to FIG. However, the same members as those in FIGS. 1, 2, and 5 are denoted by the same reference numerals, and description thereof is omitted.
The code | symbol 61 in a figure shows the wire connected with the end of the plate-shaped member 52b. A central portion of a rod-shaped member 62 is connected to the wire 61, and the tray 34 is connected to the rod-shaped member 62 via a plurality of wires 63.

  According to the sixth embodiment, as in the second embodiment, the thermal influence by the electric heater 35 in the reaction container 22 can be suppressed, and the measurement object 33 can be always measured with high accuracy, and the reaction container 22 can be measured. It can be smoothly discharged out of the reaction vessel without leaving any residual gas inside.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, the material of the wire is not limited to tungsten (W) or stainless steel (SUS304), but may be Pt or Mo, for example. Further, in the above-described embodiment, the case where the weight of the object to be measured is measured when the element is desorbed from the object to which the element is adsorbed is described. The same applies to the case of measuring the weight of the object to be measured.

  21, 41, 42 ... vacuum container (first container), 22 ... sealed container (second container), 23 ... connecting pipe, 24 ... heat shield plate, 25 ... balance, 26 ... wire, 27 ... magnetic body, 28 ... Permanent magnet, 29 ... Non-magnetic material, 32 ... Cooling mechanism, 33 ... Object to be measured, 34 ... Dish, 35 ... Electric heater, 36 ... Gas introduction pipe, 37 ... Discharge pipe, 44 ... Balance rod (balance member), 46, 47 ... first wire, 48, 53 ... stopper, 49 ... second wire, 51 ... inverted T-shaped member, 52 ... cantilever.

Claims (6)

A device for measuring the amount of adsorption / desorption of an element for measuring the amount of an element adsorbed on a measured object or the amount of an element desorbed from the measured object,
A balance for measuring the weight of the object to be measured;
A saucer on which the object to be measured is placed, positioned so as to be positioned below the balance;
A connecting member for connecting the balance and the tray;
A first container containing the balance;
A second container that contains the saucer and includes a heating source for heating the object to be measured;
A heat shield mechanism for shielding the balance in the first container from the heat of the heating source;
An apparatus for measuring the amount of adsorption / desorption of an element, comprising an exhaust mechanism for introducing gas into the second container from the lower part of the container and exhausting the gas from the upper part. Having a plurality of balances spaced apart from each other;
The connecting member includes a balance member that is vertically movable between the balance and the tray, a first wire that connects each of the balances and both ends of the balance member, and a central portion of the balance member. 2. The element adsorption / desorption amount measuring apparatus according to claim 1, wherein the element is composed of a second wire connecting the tray and the second wire.   3. The element adsorption / desorption according to claim 1, wherein the heat shield plate is provided in the first container or in a connecting pipe that connects the first container and the second container. Quantity measuring device.   The heat shield plate has an annular magnetic body having a central hole through which the first wire is passed and the inside is a hollow portion, an annular permanent magnet disposed in the magnetic body, and an inner side of the permanent magnet 4. An annular nonmagnetic material disposed on the magnetic material and a magnetic fluid disposed around a first wire passing through a central hole of the magnetic material. 5. A device for measuring the amount of adsorption and desorption of elements. Having a plurality of balances spaced apart from each other;
The connecting member has an inverted T-shaped member consisting of a supporting shaft fixed at one end to the bottom of the tray and a horizontal bar connected to the supporting shaft so as to intersect the supporting shaft, and one end at the bottom of each balance. 2. The element adsorption / desorption amount measuring apparatus according to claim 1, wherein the element is composed of two wires which are respectively connected and the other ends are respectively connected to both ends of the horizontal bar of the inverted T-shaped member.   The connecting member is a plate-like member whose upper end is fixed to the bottom of the tray, one end is connected to the lower end of the supporting shaft, the other end is fixed, and the other end is a fulcrum and can be moved vertically. 2. The element adsorption / desorption measuring device according to claim 1, comprising a cantilever comprising: a wire having one end connected to the bottom of the balance and the other end connected to the plate member.

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