JPH0737930B2 - Thermobalance device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a thermobalance device, and particularly to high sensitivity and high sensitivity without causing errors due to convection or buoyancy change in a heating furnace during temperature rise / fall. It relates to a device that can measure accuracy.

[Prior Art] Known examples of this type of thermobalance are disclosed in Japanese Patent Publication Nos. 54-27158 and 54-27159.

In Japanese Patent Publication No. 54-27158, a fulcrum is provided at the tip of both arms of a main balance, and a subbalance is suspended at each fulcrum, and one arm of each subbalance passes vertically through the fulcrum of the main balance. The sample and the standard sample are placed in the same furnace by respectively extending to the vicinity of the line and suspending the sample and the standard sample at the tip of each arm.

Further, in Japanese Patent Publication No. 54-27159, a connecting rod having the same length as the balance arm is arranged in parallel with the arm, and a vertical line passing through the fulcrum of the balance intersects with the connecting rod. A link mechanism is formed by rotatably connecting the connecting rod and two supporting rods arranged vertically to each other so as to be rotatably attached to both ends of the arm of the balance and both ends of the connecting rod. By arranging the sample and the standard sample, which are attached to their tips by bending the support rod, in the vicinity of the vertical line, these are housed in the same furnace.

In all of these conventional thermobalance devices, when the same force is applied to the sample and the standard sample, these forces act on the tips of both arms of the balance and are canceled, so that they appear as a change in weight. Absent. Therefore, for example, even when the convection in the heating furnace or the buoyancy of the sample or the like changes in the process of raising or lowering the temperature of the heating furnace in which the sample and the standard sample are accommodated, the change in the sample due to these changes Since the forces acting on and the standard sample are almost the same, these forces are canceled and do not appear as a weight change. on the other hand,
When a weight change occurs in either the sample or the standard sample, the weight change can be detected in the same manner as a normal balance. Thus, even if the balance is made extremely sensitive, it is not affected by convection or buoyancy, so that minute weight changes can be measured with relatively high accuracy.

[Problems to be Solved by the Invention] However, these conventional thermobalance devices are different from those disclosed in Japanese Patent Publication No. 54-27158 in order to store a sample and a standard sample in the same furnace. , One arm of each sub-balance suspended on both arms of the main balance is extended to the vicinity of the vertical line passing through the fulcrum of the main balance, and at the tip of each arm (Japanese Patent Publication No. 54-27159).
In the case of No. No., the support rods rotatably connected to both arms of the balance are bent and extended to the vicinity of the vertical line passing through the fulcrum of the balance, and the sample and the standard sample are attached. It is configured to suspend and. That is, according to this configuration, the length of one arm of the sub balance or the length of the arm extended by bending the support rod is necessarily the main balance,
Alternatively, it should be approximately the same length as one arm of the balance. For this reason, if the length of the arm of the balance is increased in order to make the balance highly sensitive, the arm of the sub-balance or the arm of the support pestle is lengthened accordingly. Then, Japanese Examined Japanese Patent Publication No. 54-27
In the one disclosed in Japanese Patent No. 158, since the weight 9 suspended on the other arm of the sub-balance has to be made heavier by that amount, the whole balance system becomes heavy and the sensitivity is lowered thereby. The effect of improving the sensitivity by lengthening the arms of the balance is largely offset. In addition,
In the one disclosed in Japanese Patent No. 27159, the arm of the supporting rod must be lengthened by the lengthening of the arm of the balance, and the weight of the balance is increased by the increase of the moment due to the lengthening, thereby increasing the balance system. In addition to making the whole heavier, the vertical component force acting on the supporting rod (5) by the connecting rod (3) when the balance is trying to swing to any one of them also increases by the increase of the moment, and in addition, the connecting rod ( Since the force acting on each fulcrum of 3) also increases, the frictional force of each fulcrum also increases, and the effect of improving the sensitivity by lengthening the arm of the balance is largely offset.

As described above, each of the above-mentioned conventional thermobalance devices has a certain limit in improving its sensitivity.

An object of the present invention is to provide a thermobalance device capable of eliminating such drawbacks of the conventional thermobalance device and further improving sensitivity and accuracy.

[Means for Solving Problems] The thermobalance device according to the present invention makes it possible to easily realize higher sensitivity and higher accuracy by using two balance systems. Is a first balance supported on a first fulcrum and a second balance supported on a second fulcrum provided at a constant distance from the first fulcrum. Each sample is extended to the vicinity of a vertical line passing through the midpoints of the first and second fulcrums, and a sample and a standard sample are attached to each tip, and these are housed in the same furnace. It has a structure provided with a connecting means for connecting the respective tips so that the forces applied to the tips of the other arms of the respective balances act on each other without disturbing the operation.

[Operation] The load applied to one arm of the first balance is applied to the other arm of the second balance by the operation of the connecting rod via the other arm. Therefore, these first and second balances are balanced by adjusting the weight applied to one arm of each of these balances. In this state, if the same force is applied to the sample and the standard sample, these forces are canceled by the action of the connecting means, and no change occurs in the balance system. On the other hand, when a force is applied to only one of the sample and the standard sample, for example, only the sample, the balance between the two balances is lost according to the force, and each balance is tilted, which is detected as a weight change. be able to.
Even if the arms of the respective balances are made sufficiently long, there is no factor for canceling out the effect of improving the sensitivity due to the lengthening of the arms, so that it is possible to easily obtain a thermobalance device with extremely high sensitivity.

[Embodiment] FIG. 1 is a diagram showing a configuration of a first embodiment of the present invention, and FIG. 2 is a diagram showing a configuration of a second embodiment of the present invention.

In FIG. 1, reference numeral 1 is a first fulcrum,
A second fulcrum 2 is provided at a constant distance from the fulcrum 1 of the first fulcrum 1, and the first balance 3 is supported on the first fulcrum.
A second balance 4 is supported on the second fulcrum. These arms 5 and 6 of the first and second balances 3 and 4 are the fulcrums
Support rods 9 and 8 that extend to the vicinity of a vertical line passing through the midpoints of 1 and 2 and extend vertically to the tip of each through fulcrums 7 and 8.
10 is rotatably supported, and these support rods 9
Sample holders 11 and 12 are attached to the upper ends of the drawings of FIGS. 10 and 10, respectively, and sample trays 13a and 1a for filling the sample 13 and the standard sample 14 at the tips of these sample holders 11 and 12, respectively.
4a are attached and they are housed in the same furnace 15.

On the other hand, weights 16 and 17 are attached to the lower ends of the supporting rods 9 and 10 in the figure in order to keep these supporting rods vertically. Further, the other arm 18 of each of the balances 3 and 4 is
Numerals 19 and 19 are extended downward and their tip portions are connected to each other by a wire 20 as a connecting means.

In the above configuration, the first and second balances 3 and 4
Is loaded with the weight of the sample 13 and the standard sample 14 through the support rods 9 and 10 and the like to the tips of the arms 5 and 6, respectively. These weights are applied to the arms 18 and 18 of the balance.
The balance is canceled by the wire 20 connecting the tips of 19 so that the balances are balanced when the weights are equal, and tilt in opposite directions when the weights are different. Moreover, even if the balance systems are tilted by the action of the weights attached to the lower ends of the support rods 9 and 10, the support rods are held substantially vertically and do not interfere with the measurement.

When measuring thermogravimetric changes with this thermobalance device,
First, the first balance 3 and the second balance 4 are adjusted so as to be balanced, and then the sample pan 13a is filled with the sample 13 that causes a weight change by heating, and the sample pan 14a is heated to change the weight. The standard sample 14 that does not occur is filled and these are heated by the heating furnace 15. This allows the sample to be
When a weight change occurs in 13, the respective balances are tilted, so that the weight change of the sample can be detected by detecting this with a well-known detection device (not shown).

The above-described first embodiment has the following advantages. That is, when the same force is applied to the sample 13 and the standard sample 14 due to the change in convection or the buoyancy when the sample 13 and the standard sample 14 are heated and heated, these cancel each other and are not detected as a weight change. Therefore, a minute weight change can be measured with extremely high accuracy without being affected by convection or buoyancy.

In addition, since the two arms 3 and 4 are used to extend one arm 5 and 6 of each balance to the vicinity of the vertical line passing through the midpoints of the fulcrums 1 and 2 of each balance, respectively, the sample 13 and the standard The sample 14 and these arms can be housed in the same furnace 15 by just arranging them almost right above the tips of the arms 5 and 6, and each supporting rod can be horizontally arranged like the conventional thermobalance device. No need to extend in the direction. Therefore, if the arms 5 and 6 of each balance are lengthened, it directly leads to the improvement of the sensitivity of each balance, and therefore a balance with extremely high sensitivity can be easily obtained.

Further, since the tips of the other arms 18 and 19 of the respective balances 3 and 4 are connected by the wire 20, compared with the case of connecting using a rigid connecting rod and a fulcrum member etc. without using a wire. Since it is not necessary to accurately match the positional relationship of each fulcrum, assembly and adjustment is easy and the manufacturing cost is low.

FIG. 2 shows a second embodiment of the present invention. In this embodiment, the balance systems in the first embodiment are arranged in a substantially inverted state, and the supporting rods 9 and 10 and the sample holder are arranged. Wires 9a and 10a are used instead of 11, 12 and the sample 13 and the standard sample 14 are suspended on the tips of the arms 5 and 6 of the balances 3 and 4 and housed in the heating furnace 15. In addition, instead of using the wire 20 as a connecting means for connecting the tips of the other arms 18, 19 of the respective balances 3, 4, instead of the rigid connecting rod 20a and both ends of the connecting rod 20a, the ends of the arms 18, 19 respectively. A fulcrum member 2 that is rotatably attached to
By using 0b and 20c, a so-called hanging type thermobalance device is obtained. In this embodiment, unlike the case of the first embodiment, the advantage obtained by using the wire as the connecting means is not obtained, but the first embodiment is used.
In the case of the embodiment, the supporting rods 9 and 10 and the fulcrum members 7 and 8 which are required
Since the sample holders 11 and 12 are not required, the configuration is extremely simple, and the weight of the entire balance system can be reduced, making it easier to increase the sensitivity and using fewer parts. Also, it has excellent advantages such as easy assembly and adjustment.

[Effects of the Invention] As described in detail above, according to the present invention, when the same force is applied to the samples and the standard sample by heating due to convection or buoyancy change, these are Measures minute changes in weight with extremely high accuracy without being affected by convection or buoyancy, unless they are canceled by the action of the connecting means connecting the other arms of the balance and detected as changes in weight. Along with being able to increase the sensitivity of each balance by increasing the length of one arm of each balance, the effect of improving the sensitivity by lengthening that arm as in the conventional thermobalance device can be obtained. Since there is no compensating factor, it has an excellent effect that an extremely sensitive balance can be easily obtained.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a first embodiment of the present invention, and FIG. 2 is a diagram showing a configuration of a second embodiment of the present invention. 1 ... First fulcrum, 2 ... Second fulcrum, 3 ... First balance, 4 ... Second balance, 5,6 ... One arm of the first and second balances, 13 …… Sample, 14 …… Standard sample, 15 …… Heating furnace, 18,19 …… The other arm of the first and second balances, 20,20a
... A wire and a connecting rod that are connecting means.

Claims (1)

[Claims] 1. A first balance supported on a first fulcrum and a second balance supported on a second fulcrum, which is provided at a constant distance from the first fulcrum, respectively. The arms are respectively extended to the vicinity of a vertical line passing through the midpoints of the first and second fulcrums, a sample and a standard sample are attached to the respective tips, and these are housed in the same furnace, and A thermobalance device, characterized in that a connecting means is provided for connecting the respective tips so that the forces applied to the tips of the other arms of the respective balances act on each other without disturbing the operation of the respective balances.