JPH0750049B2 - Thermal expansion coefficient measuring device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a thermal expansion coefficient measuring device, and particularly to a thermal expansion coefficient measuring device which is preferably used for an irregularly shaped object or an object having a large displacement amount during thermal expansion. It is about.

[Prior Art] As an example of a conventional thermal expansion coefficient measuring device, for example, a structure shown in FIG. 2 is known.

This conventional thermal expansion coefficient measuring device 1 includes a fixed part 2, a pair of movable parts 3 (3a, 3b) for respectively holding a standard sample A and a measured sample W between the fixed part 2, and both movable parts. Three
(3a.3b), the differential transformer 4 for detecting the relative amount of movement of the two, and the movable parts 3 (3a, 3b) are connected to the movable parts 3 (3a, 3b). 3a and 3b) is provided with holding force adjusting means 5 (5a and 5b) for adjusting the holding force applied to each of the samples A and W, and a heater H for heating each of the samples A and W. The force adjusting means 5a, 5b includes a lever 6 (6a, 6b) rotatably arranged around a fulcrum S, and a balance weight 7 (7a, 6a, 6b) provided at one end of the lever 6 (6a, 6b). 7b) and a balance weight 8 (8a ・ 8) for fine adjustment provided near the balance weight 7 (7a ・ 7b)
8b), and the movable portions 3 (3a, 3b) are engaged with the other end of the lever 6 (6a, 6b).

The thermal expansion coefficient measuring device 1 holds the standard sample A and the measurement sample W between the fixed part 2 and the movable parts 3 (3a and 3b), respectively, and the balance weights 7 (7a and 7b). ), 8 (8a / 8b), the movable part 3 (3a / 3
The holding force acting from b) to each sample A / W is adjusted to be almost zero, then each sample A / W is heated by the heater H, and the elongation amount between both samples A / W caused by this heating is adjusted. Is electrically detected by the differential transformer 4 as a relative movement amount between the movable parts 3 (3a, 3b) holding them, and the data of the measurement sample W is detected by this data and the characteristics of the standard sample A. The coefficient of thermal expansion is calculated.

[Problems to be Solved by the Invention] Problems to be solved by the present invention are as follows.

That is, in the thermal expansion coefficient measuring device 1 described above, the balance structure composed of the lever 6 and the balance weights 7 and 8 is used to adjust the holding force applied to each of the samples A and W. If the displacement of
The holding amount set for the measurement sample W changes due to an increase in the amount of rotation of the movable part 3 (3a, 3b), and the action line of the holding force and the extending direction of the measurement sample W are inclined. It is assumed that the deviation will occur.

Therefore, the application to the measurement sample W having a large elongation amount or the measurement in the viscous region after the softening point is limited.

Further, since the distance between the fixed portion 2 and the fulcrum S is set substantially uniquely, and the saw 6 must be in a horizontal state for setting the holding force, the fixed portion 2 and the movable portion 3 ( The distance between 3a and 3b) is naturally regulated.

As a result, the shape of the sample W that can be measured is also limited, making it difficult to apply it to a long sample.

Especially, in the measurement requiring accuracy, the change of the above-mentioned various conditions must be strictly controlled.
In addition, the shape of the measurement sample W must be created in conformity with the standard shape, and the work required for measurement becomes complicated.

[Means for Solving the Problems] An object of the present invention is to provide a thermal expansion coefficient measuring device capable of effectively solving the above-mentioned problems. In order to achieve this object, the present invention particularly relates to the device. The fixed part fixed to the main body, and holds the measurement sample between the fixed part,
In addition, the sample holding means including a movable part that is moved in the expansion / contraction direction according to the expansion / contraction amount of the measurement sample, the movement amount detection means connected to the movable part to detect the movement amount, and the movable part. From the holding force adjusting means for adjusting the holding force applied to the measurement sample from, the holding force adjusting means, the liquid tank fixed to the apparatus main body, is immersed in the liquid in the liquid tank, It is characterized by comprising a float for generating an external force in the direction of pressing the measurement sample on the movable portion by the buoyancy and a balance weight for generating an external force in the direction of canceling the buoyancy.

[Operation] The thermal expansion measuring device of the present invention adjusts the holding force applied to the measurement sample by adjusting the upward external force generated by the buoyancy of the float, the weight of the movable portion, the weight of the measurement sample, and the adjustable balance. This is done by balancing with the downward external force, which consists of the weight of the weight, and these external forces are aligned along a straight line so that the magnitude and direction of the holding force applied to the measurement sample can be determined regardless of the moving position of the movable part. This is to hold it constant and to expand the movable range of the movable part.

[Embodiment] An embodiment of the present invention will be described below with reference to FIG.

In FIG. 1, reference numeral 10 indicates a thermal expansion coefficient measuring device 10 according to this embodiment, which holds a measurement sample W between a fixed part 11 fixed to the device main body B and the fixed part 11. And,
A sample holding means 13 including a movable part 12 that is moved in the expansion / contraction direction according to the expansion / contraction amount of the measurement sample W, and a movement amount detection means connected to the movable part 12 to detect the movement amount.
14 and a holding force adjusting means 15 for adjusting the holding force applied from the movable part 12 to the measurement sample W. The holding force adjusting means 15 includes a liquid tank 16 fixed to the apparatus main body B,
A float 17 that is poured into the liquid in the liquid tank 16 to generate an external force in the direction of pressing the measurement sample W on the movable portion 12 by the buoyancy force, and a balance weight that generates an external force in the direction of canceling the buoyancy force. It has a basic configuration consisting of 18.

Next, these will be described in detail.
Is a guide tube 19 which is fixed to the apparatus main body B along the vertical direction.
And a support plate 20 fixed at a predetermined interval above the guide tube 19 (upper side in the figure) and holding one end portion (upper end portion) of the measurement sample W.
A support rod 21 that constitutes the movable portion 12 and holds the other end portion (lower end portion) of the measurement sample W is fitted in 19 so as to be vertically movable.

A frame body 22 that forms a space portion is directly attached to the lower end portion of the support rod 21 directly below the support rod 21.

As the moving amount detecting means 14, a differential transformer 23 is used in the present embodiment, and the core 23 of the operating transformer 23 is used.
a is fixed to the lower end of a frame body 22 attached to the support rod 21 so that it can be moved up and down together with the movable portion 12, and a felt 23b of a differential transformer 23 is fixed to the apparatus main body B.

Therefore, when a relative movement occurs between the fixed portion 11 and the movable portion 12, the movement causes the core 23a and the field 23b to move.
The relative movement with and is done at the same time.

The liquid tank 16 constituting the holding force adjusting means 15 includes the frame body 22.
Is disposed in the space formed by
It is arranged immediately below 21 with a proper gap formed between it and the frame body 22, and an upper part thereof is opened, and a liquid L such as pure water or silicon oil is stored inside.

The float 17 is attached to the frame body 22 so as to be coaxial with the support rod 21 and to the connecting rod 24 integrally projecting toward the inside of the frame body 22, as described above. In addition, the support rod 21 is pushed upward along the length direction thereof by the buoyancy generated in the state of being poured into the liquid L.

The float 17 includes the support rod 21, the frame body 22, the core 23a, and the measurement sample W held by the support rod 21.
The shape is set so as to generate buoyancy capable of pushing up the total weight of the.

The balance weight 18 is attached to the upper part of the frame 22 so as to surround the support rod 21, and is selected and used according to the weight, shape, material, etc. of the measurement sample W. When W is set between the fixed portion 11 and the movable portion 12, the load is set to 0.5 to 1.5 g with respect to the measurement sample W.

The thermal expansion coefficient measuring device 10 of the present embodiment configured in this way
The procedure for measuring the coefficient of thermal expansion will be described below.

First, the balance weight 18 is placed on the upper portion of the frame body 22, and the weight of the support rod 21, the frame body 22, and the differential transformer core 23a and the like is balanced with the buoyancy generated by the float 17, and the sample is The holding force of the holding means 13 is set to zero.

After mounting the standard sample A between the fixed part 11 and the movable part 12, the weight of the balance weight 18 is gradually increased to make the standard sample A 0.5.
Give a load of ~ 1.5g.

In this state, the heater H is driven to heat the standard sample A to a predetermined temperature.

By such an operation, the support rod 21, the frame body 22, and the float 17 are pushed down along with the thermal expansion of the standard sample A, and the core 23a is also pushed down and relatively moved with respect to the field 23b. Then, when the relative movement between the core 23a and the field 23b is performed, this movement amount becomes
It is electrically detected as the amount of thermal expansion of the standard sample A under the heating temperature.

Furthermore, by performing such an operation while sequentially changing the heating temperature, the relationship between the temperature and the thermal expansion amount for the standard sample A is obtained, and based on this, the mechanical characteristics of the thermal expansion coefficient measuring device 10 are obtained. Is obtained.

Here, this measurement result is stored in the calculation means as reference data.

Next, a measurement sample W is set between the fixed part 11 and the movable part 12 in place of the standard sample A in the same procedure and heated, and the relationship between the temperature and the thermal expansion amount is measured.

Then, the thermal expansion coefficient of the measurement sample W is calculated by a calculation in which the correction based on the mechanical characteristics of the thermal expansion coefficient measuring device 10 obtained from the measurement operation on the standard sample A is added to the measurement result.

When measuring such a coefficient of thermal expansion, the expansion / contraction direction of the sample A (W) and the acting direction of the holding force applied to the sample A (W) are substantially aligned with each other. Irrespective of the above, a constant holding force is applied to the sample A (W) from a constant direction.

Therefore, a large amount of movement of the movable portion 12 can be obtained, and effective measurement can be performed even with an irregular sample such as a long object.

In addition, even when a large amount of displacement occurs, such as when the measurement sample W reaches a viscous flow region that exceeds the characteristics or the softening point, the allowable movement amount of the movable portion 12 is large, and various setting conditions are set. As described above, since the movable portion 12 is held substantially constant regardless of the moving position, it is possible to measure in a wide displacement range.

Furthermore, since an amorphous sample may be used, processing of the sample is unnecessary and the measurement operation becomes simple.

It should be noted that the shapes, sizes, and the like of the respective constituent members shown in the above embodiment are examples, and can be variously changed based on design requirements and the like.

[Effects of the Invention] As described above, according to the present invention, as a means for adjusting the holding force for a sample, a liquid tank fixed to the apparatus main body,
A float that is immersed in the liquid in the liquid tank to generate an external force in the direction of pressing the measurement sample on the movable portion by its buoyancy and a balance weight that generates an external force in the direction of canceling the buoyancy Therefore, it has the following excellent effects.

Regardless of the moving position of the movable part, various conditions such as the magnitude of the holding force applied to the sample and the direction of action can be held constant, and as a result, the movable range of the movable part can be expanded and the displacement amount It enables measurement of large samples or viscous flow regions past the softening point.

It is possible to set a large gap between the fixed part and the movable part during setting, which makes it possible to perform measurements on irregularly shaped samples or long samples, and reduces the processing on the sample to make measurement operations. It can be simple.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of the present invention, and FIG. 2 is a schematic view showing a conventional structure example. 10 ... Thermal expansion coefficient measuring device, 11 ... Fixed part, 12 ... Movable part, 13 ... Sample holding means, 14 ... Moving amount detecting means, 15 ...
… Holding force adjusting means, 16 …… Liquid tank, 17 …… Float, 18…
... Balance weight, A ... Standard sample, B ... Device body, W ... Measurement sample.

Claims (1)

[Claims] 1. A fixed part fixed to an apparatus main body, and a movable part which holds a measurement sample between the fixed part and is movable in the expansion / contraction direction according to the expansion / contraction amount of the measurement sample. The sample holding means, the moving amount detecting means connected to the movable part to detect the moving amount thereof, and the holding force adjusting means for adjusting the holding force applied to the measurement sample from the movable part, The holding force adjusting means is a liquid tank fixed to the apparatus main body, and a float which is put into the liquid in the liquid tank and generates an external force in a direction of pressing the measurement sample against the movable portion by its buoyancy. A thermal expansion coefficient measuring device comprising: a balance weight that generates an external force in a direction to cancel the buoyancy.