JPH052841Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a viscoelasticity measuring device for tracking the curing process of vulcanized rubber, thermosetting resin, etc.

[Prior Art] Viscoelasticity tests are conducted to determine whether unvulcanized rubber or thermosetting resin will have desired physical properties after vulcanization or thermosetting, respectively. . Among these, regarding the vulcanization test
ISO-3417 and Japan Rubber Association standard SRIS
3105-1980 specifies the test method.

Figure 4 shows a conventional device, for example, JP-A-53-14479.
FIG. 2 is an enlarged cross-sectional view of the peripheral portion of the die disclosed in the publication and defined as SRIS 3105 die type B. In the figure, 1 is the upper die (first die),
2 is the lower die (second die), 3 is the upper fixed die (first fixed die), 4 is the lower fixed die (second fixed die), and 5 and 6 are the upper and lower seals (O-rings), respectively. be. 7 is the torque detection axis;
8 is a drive shaft, 10 and 11 are each a heating plate, 1
2 and 13 are temperature detectors, respectively. As shown in the figure, the measuring section of the conventional device consists of upper and lower dies 1,
2. Consists of four dies, upper and lower fixed dies 3 and 4, and two upper and lower seals (O-rings) 5 and 6. When the upper half of the measuring section is lifted upward by the air cylinder located above the figure, a shallow disc-shaped recess formed by three parts: the lower die 2, the lower fixed die 4, and the lower seal 6 is exposed. do. This shape with a depression on the bottom side is convenient because there is no need to worry about spilling when pouring even a low-viscosity liquid sample before hardening, but on the other hand, after hardening, the lower fixed die 4
Since the sample does not protrude from the top surface of the sample, there is no handhold during the stripping operation and it is extremely difficult to peel off. Even so, in the case of a rubber sample, it can be peeled off by piercing it with a sharp tool, but in the case of a hard and durable resin sample or a sample with strong adhesive properties, this becomes a very difficult task and significantly impedes measurement efficiency.

[Problems to be solved by the invention] As described above, in the conventional apparatus, it takes a long time to remove the cured sample after the measurement is completed, which hinders the measurement efficiency.

It is an object of the present invention to eliminate such conventional drawbacks and provide a viscoelasticity measuring device that can efficiently measure viscoelasticity.

[Means for Solving the Problems] In order to achieve such an object, the present invention includes first and second dice facing each other, and a first fixing member fixed at a position surrounding the first die. a die, a second fixed die fixed in a position surrounding the second die, and a second fixed die housed within the second fixed die;
The present invention is characterized by comprising an intermediate plate that can be easily attached and detached.

[Function] The viscoelasticity measuring device of the present invention has an intermediate plate in addition to the conventional four die configuration.
The hardened sample that has been measured can be easily removed.
Measurement efficiency can be improved.

[Examples] Examples of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a sectional view of a measuring section in an embodiment of the present invention, and FIG. 2 is an exploded perspective view thereof. In both figures, 21 is an upper die (first die), 22 is a lower die (second die), 23 is an upper fixed die (first fixed die), and 24 is a lower fixed die (second die).
(fixed die), 25 is an intermediate plate, 27 and 28 are an upper seal and a lower seal, respectively. The intermediate plate 25 has a flange 25A, and the lower fixed die 24 is provided with at least one notch 24A (indicated by an arrow in FIG. 1). 30 is a sample, and 31 is a counterbore for a fixing screw.

When the upper structure consisting of the upper die, upper fixed die, etc. is pushed downward by the force of the air cylinder,
For fluid samples, the measurement section closes immediately, and for solid samples such as pellets and powder, as the temperature rises and melts, the measurement section closes gradually.The upper fixed die and the intermediate plate come into close contact, and the upper and lower seals close the measurement section. . At this time, the excess sample and the sample that has become redundant due to thermal expansion due to temperature rise flow out under high pressure and are accommodated in the space of the burr groove 29 provided on the upper surface of the intermediate plate.

When the upper measurement part is pulled up after the measurement is completed and the sample is cured, in most cases, separation occurs at the interface between the cured sample 30 and the upper die 21, and between the burr 30A and the upper fixed die 23, and the burr 30A and The measurement section opens leaving the cured sample 30 on the bottom side. Next, a lever-like tool is inserted into the notch 24A provided at at least one location on the periphery of the lower fixed die 24, and the collar 25A provided on the outer periphery of the intermediate plate 25 is inserted using the edge of the notch as a fulcrum. When it is pried up, the four parts (intermediate plate 25, lower seal 28, hardened sample 30, and burr 30A) come off as one as shown in FIG. The force required for this operation has little to do with the hardness of the cured sample, and depends almost solely on the adhesive strength of the sample, and even in the case of fairly strongly adhesive samples, it is necessary to apply an appropriate mold release agent in advance. This allows it to be peeled off extremely easily and quickly.

After peeling it off as one piece, remove the intermediate plate 25.
The work of removing the cured sample 30 and burrs 30A from the test piece is extremely easy because it is carried out in a large area outside. Further, in order to facilitate this operation, it is desirable that all the cylindrical surfaces of the intermediate plate 25 that come into contact with the sample 30 and the burr 30A have a so-called "pull taper". The intermediate plate 25 from which the sample and burrs have been removed is returned to the measuring section together with the lower seal 28, and after waiting for the temperature to recover, the next measurement begins. Since this sample stripping operation can normally be carried out in a fairly short time, the temperature drop in the intermediate plate 25 during this time is relatively small, and as shown in the figure, the intermediate plate 25 can be designed to have a considerably lower heat capacity than other dies. Therefore, the disturbance in the temperature equilibrium of the measuring section caused by returning the cooled intermediate plate 25 to its original position is small, and the temperature is recovered relatively quickly. In this way, the ease of sample stripping operation using the intermediate plate not only improves testing efficiency, but also has the effect of saving time for waiting for temperature recovery during high temperature measurements.

In the embodiment shown in FIG. 1, the upper die has a conical projection on the side that contacts the sample.
This protruding part has a volume that allows it to penetrate below the liquid surface at the moment the die is closed, even if the sample is in a low viscosity liquid state and is difficult to set because it bulges on the lower measurement part. This has the function of filling every corner of the measuring section space with the sample, but the present invention can also be applied to devices having upper dies of other shapes. In addition to the continuous flange, the flange provided on the outer periphery of the intermediate plate 25 includes intermittent protrusions, horizontal holes or depressions provided on a part of the outer periphery,
Alternatively, various methods such as a groove provided on the outer periphery can be used. In addition, various methods can be used for the cutout portion of the lower fixed die, such as a gap extending all around the circumference. The ring-shaped flat part provided near the inner periphery of the upper surface of the intermediate plate has the function of sealing the measuring section by bringing it into close contact with the flat part of the lower surface of the upper fixed die 23, and maintaining the necessary internal pressure of the sample during measurement. has. However, if the melt viscosity of the uncured sample is low, the internal pressure of the sample decreases during measurement due to insufficient sealing function in this area.
This may lead to slippage at the interface between the sample and the die and foaming within the sample, resulting in an unstable curing curve. Figures 5, 6 and 7 show examples of effective sealing methods for such low viscosity samples.

FIG. 5 shows that by widening the radial width of the ring-shaped flat portion (indicated by A in the figure), the flow resistance when the excess sample flows into the burr groove 29 is increased, and the flow resistance is counteracted. An example of a method for increasing the internal pressure of the sample generated as a force is given below. Such methods are effective for samples with intermediate melt viscosities (eg, tens to thousands of centiStokes). In addition, this method has a simpler structure than the method that uses an elastic sealing material described below, so it has the advantage of not increasing the number of consumable parts, increasing the effort of replacing them, and increasing the effort of cleaning after measurement. There is.

In the case of samples with even lower melt viscosity (for example, 10 cm Stokes or less), a stable curing curve can be obtained using a sealing method that simply brings smooth metal surfaces into close contact, as illustrated in Figures 1 and 5. It may be difficult to maintain the necessary internal sample pressure. In such a case, a sealing method using an elastic sealing material as illustrated in FIG. 6 or 7 is effective. FIG. 6 shows an embodiment of a method in which a ring-shaped groove is provided in a flat portion of an intermediate plate and an elastic sealing material 31 (hereinafter referred to as an intermediate seal) such as a commercially available O-ring is embedded. By creating a groove shape with an appropriate tightening margin so that an appropriate amount of elastic deformation is applied to the intermediate seal when closing the measurement section, it is possible to maintain the necessary internal pressure of the sample even for low-viscosity samples, and the hardening process becomes possible. Curve stability can be improved. Further, such a sealing method using an elastic sealing material can also be achieved by providing a groove on the upper fixed die side and embedding the intermediate seal 32, as illustrated in FIG.

[Effects of the invention] As explained above, by adding an intermediate plate that can be easily attached and detached to the measurement section, it is possible to easily remove the cured sample that has been measured, and the measurement efficiency can be improved.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the measuring section in an embodiment of the present invention, Fig. 2 is an exploded perspective view of the embodiment shown in Fig. 1, Fig. 3 is a sectional view showing a removed measured hardened sample, and Fig. 4 The figure shows a cross-sectional view of the measurement section of a conventional viscoelasticity measuring device.
The figure is a sectional view of a measurement section for low melt viscosity samples in which an elastic sealant is embedded in the intermediate plate, and FIG. 7 is a sectional view of a measurement section for low melt viscosity samples in which an elastic sealant is embedded in an upper fixed die. 7... Torque detection axis, 8... Drive shaft, 21...
Upper die, 22...Lower die, 23...Upper fixed die, 24...Lower fixed die, 24A...Notch, 25...Intermediate plate, 25A...Brim portion, 27...Upper seal, 28... ...Lower seal, 29
...Burr groove, 30...Sample, 31, 32...Intermediate seal.

Claims (1)

[Scope of utility model registration request] first and second dice facing each other, a first fixed die fixed at a position surrounding the first die, and a second fixed die fixed at a position surrounding the second die, A viscoelasticity measuring device characterized by comprising an intermediate plate that is housed in the second fixed die and that is easily removably fitted.