JPH0444224B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method and method for measuring penetration or penetration of a pasty substance such as petroleum asphalt or penetration of grease, etc. Regarding equipment.

[Background technology and its problems]

Penetration is the amount of penetration of the penetration measuring needle into the measurement sample when the needle with a constant load is allowed to fall freely for a certain period of time into the measurement sample kept at a constant temperature in a thermostatic chamber. be. There is a standard for measuring the penetration of petroleum asphalt, for example, in JIS-K-2207. In addition, the material is softer than petroleum asphalt.
For example, in the case of grease, the hardness, ie, the hardness, of the grease is measured using a similar device using a measuring needle of a different shape from that used for penetration. For measuring the durability of this grease, please refer to JIS-K-
2220, and JIS-K-2235 stipulates the measurement of penetration and penetration of petroleum waxes.

When measuring hardness such as penetration, it is first necessary to bring the tip of a needle for measuring penetration or hardness into contact with the sample to be measured so as not to damage the surface of the sample. However, in conventional measurement methods, the height of the sample stage must be adjusted by holding up an electric light to cast the shadow of the measuring needle tip onto the surface of the measuring sample, or by looking at the measuring needle tip in a mirror. It was impossible. Therefore, skill is required for measurement operations, measurement results tend to vary from person to person, and accurate measurement results are not necessarily easily obtained.

Furthermore, after the tip of the measuring needle comes into contact with the surface of the measuring sample, it is necessary to allow the measuring needle to enter the measuring sample for a certain period of time, but this operation must be completed in a short period of time, usually only a few seconds. Must be.
Therefore, in this case as well, skill is required for the measurement operation, and measurement results tend to vary from person to person.

Therefore, in order to overcome these difficulties,
A device for automatically measuring penetration has already been proposed (Japanese Patent Publication No. 49-31677). In this device,
The needle for measuring penetration was suspended from the dial gauge via an elastic thread, but there were cases where the resistance of the gear when moving the dial gauge could not be ignored. In other words, unlike standards such as JIS, it is difficult to say that the measurement is performed by letting the needle for measuring penetration fall freely; In some cases, it may be necessary to change the approach time or introduce a correction formula, and from these points of view it is not always sufficient.

[Purpose of the invention]

The object of the present invention has been made in consideration of the above-mentioned circumstances, and it is an object of the present invention to provide a method and a measuring device for measuring penetration or penetration, which can easily obtain highly accurate measurement results without requiring special skill. It is about providing.

[Means and actions for solving problems]

In order to achieve the above object, the first invention suspends a needle for measuring penetration or penetration with a constant load toward a measurement sample from a flexible thread connected to a strain gauge. The strain gauge changes the contact between the measuring needle and the surface of the measuring sample when the needle and the measuring sample gradually approach each other based on the relaxation of the flexible thread caused by the contact between the measuring needle and the measuring sample surface. Then, with the flexible thread relaxed, the measuring needle is introduced into the measuring sample for a certain period of time, and the amount of penetration of the measuring needle into the measuring sample at that time is detected. It is characterized in that it is determined from the output signal of a linear direction displacement detector connected to the measuring needle.

Further, the second invention provides a needle portion having a needle for measuring penetration or penetration and having a constant weight as a whole, a flexible thread hanging from the needle portion, and a flexible thread. a strain gauge connected to the other end side, a measurement sample disposed below the measurement needle, a moving means for adjusting the positional relationship between the measurement needle and the measurement sample along the extension direction; The present invention is characterized in that it is provided with a linear direction displacement detector that detects the amount of displacement of the measuring needle when the measuring needle is allowed to fall freely into the measuring sample for a certain period of time due to the weight of the needle portion.

In the method and device for measuring penetration or penetration according to the present invention, the contact between the measuring needle and the surface of the measuring sample can be detected with high precision by using a strain gauge, and the contact between the measuring needle and the surface of the measuring sample can be detected with high precision. The amount of intrusion into the measurement sample can also be detected with high precision by using a linear displacement detector.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows an overall configuration diagram of an embodiment in which the present invention is applied to a penetration measuring device. In the figure, a needle portion 1 is composed of a penetration measuring needle 2, a weight 3, and a needle holder 4. The tip of the penetration measuring needle 2 is directed vertically downward, and the weight 3
Therefore, the needle part 1 has a constant weight as a whole, e.g.
Adjusted to have 100gr.

The needle part 1 is connected to a strain gauge 6 via a flexible thread 5.
hanging from. This flexible thread 5 is used to sensitively sense the initial contact between the tip of the needle 2 for measuring penetration and the sample surface, and is made of nylon, other synthetic fibers, or silk thread with appropriate elasticity and strength. A flexible thread is used. Further, the strain gauge 6 used has a structure in which a normal thin film gauge body is fixed to a support.

A rack 7 is fixed to the support of the strain gauge 6, and a pinion 8 is engaged with the rack 7.
The pinion 8 is attached to the output shaft of the first motor 9, and therefore the strain gauge 6 is attached to the output shaft of the first motor 9.
It is adapted to be moved vertically in the up and down direction as the wheel rotates. Further, a first limit switch 11 and a second limit switch 12 are arranged at a predetermined interval in the vertical direction of the hanging of the rack 7, and the upper and lower limit positions of the rack 7, and thus the strain gauge 6, in the vertical vertical direction are detected. It is becoming more and more like this.

Below the penetration measuring needle 2, a measurement sample 15 housed in a container-shaped sample stand 14 is placed. A constant temperature medium circulation path 16 and a circulation pump 17 are attached to the sample stage 14 , and the constant temperature medium in the constant temperature chamber 18 is circulated to the sample stage 14 by the pump 17 .
5 is maintained at a constant temperature. Further, a rack 19 is fixed to the sample stand 14, a pinion 21 is meshed with the rack 19, and the pinion 21 is attached to the output shaft of a second motor 22. The penetration measuring needle 2 moves up and down along the penetration direction (that is, vertically up and down direction).

The amount of penetration (penetration) of the penetration measuring needle 2 into the measurement sample 15 is detected by a differential transformer 25 as a linear displacement detector provided at the upper end of the needle holder 4. It's summery. Differential transformer 2
5 has a coil 26, and the needle holder 4 has a coil 26.
It also serves as the iron core that moves inside. At this time, instead of the needle holder 4 serving as the iron core, a core of a normal differential transformer may be fixed to the upper end of the needle holder 4, and the lower end of the flexible thread 5 may be connected to this core.

Further, the needle holder 4 can be held at any vertical position by the clasp 31.

The clasp portion 31 is shown enlarged in FIGS. 2 and 3. In these figures, the clasp part 31
has a pair of gripping members 33 that sandwich the needle holder 4 therebetween. The pair of gripping members 33 are rotated about rotational shafts 34 at one end of each, and are connected to each other so as to sandwich the needle holder 4 by a spring 35 provided at the other end.

Further, the distance between the pair of gripping members 33 is widened by the actuating member 36 having an acute-angled tip against the biasing force of the spring 35, and the needle holder 4 is released from the clasp part 31 at this time. Become. The actuating member 36 is connected to a drive shaft 38 via a link 37, and the drive shaft 38 moves horizontally depending on the energization state of the solenoid 39, and the movement is transmitted to the actuating member 36 via the link 37. It's summery.
Further, the pair of gripping members 33 and the link 37 are supported by a support body 40.

FIG. 4 shows the control system of this embodiment. In the figure, the CPU 41 receives the output signals of the strain gauge 6 and the differential transformer 25 from the A/D converter, respectively.
In addition to being inputted via converters 42 and 43, signals from the first limit switch 11 and second limit switch 12 are also inputted. In addition, the CPU 41 includes first and second motors 9, 22, a circulation pump 17, and a solenoid 39.
In addition to outputting control signals to each of the above, data signals are sent to a recording section 44 such as a recorder or printer, and a display 45. Furthermore, a memory 46 is connected to the CPU 41.

Next, a method for measuring penetration according to this embodiment will be explained.

When measuring the penetration, first, (1) set the initial position of the penetration measurement needle 2 by bringing the penetration measurement needle 2 into contact with the surface of the measurement sample 15, and then (2) ) The penetration of the penetration measuring needle 2 into the measurement sample 15 must be detected.

(1) Method of contact between the penetration measuring needle 2 and the surface of the measurement sample 15.

With the needle holder 4 released from the clasp 31, the needle 1 is allowed to hang down from the strain gauge 6. At this time, since the weight of the needle portion 1 is applied to the strain gauge 6, a predetermined voltage is output.

The strain gauge 6 is driven by the first motor 9 to raise it, and the first limit switch 11 is activated.
Stop at the position where it operates.

The sample stage 14 is driven by the second motor 22 and raised.

When the sample stage 14 rises and the penetration part measurement needle 2 comes into contact with the surface of the measurement sample 15,
The flexible thread 5 of the strain gauge 6 is relaxed.
The output signal (voltage) of the strain gauge 6 at this time is as shown in FIG. 5, which was initially a predetermined voltage, but due to the contact, the output voltage gradually decreases as the flexible thread 5 relaxes. It changes like that. The point in time when the change value of the output signal of the strain gauge 6 reaches a preset value is defined as the position where the penetration measuring needle 2 and the surface of the measurement sample 15 come into contact.

This position is detected by the CPU 41, the second motor 22 is stopped, and the sample stage 14 is stopped.

(2) Measuring the penetration of the penetration measuring needle 2 into the measurement sample 15.

After the second motor 22 stops, the needle holder 4 is fixed by the clasp, and the position of the needle 2 (needle holder 4) for measuring penetration at this time is detected by the differential transformer 25, and the initial position is detected. It is stored in the memory 46 as .

The first motor 9 is driven, and the strain gauge 6 is
is lowered to the position where the second limit switch 12 is activated. This allows the flexible thread 5 to relax by the necessary and sufficient amount.

Release the needle holder 4 from the clasp 31. At this time, since the elastic thread 5 has already been relaxed by a sufficient amount by the above-described operation, the penetration measuring needle 2 is in a state where it can freely enter from the sample surface of the measurement sample 15.

The penetration measuring needle 2 is allowed to fall freely into the measurement sample 15 for a predetermined period of time (for example, 5 seconds).

After a predetermined period of time has elapsed, the clasp 31 is actuated to fix the needle holder 4 and stop the penetration measuring needle 2 from entering the measurement sample 15.

The position of the penetration measuring needle 2 when the needle 2 is stopped is detected by the differential transformer 25, and the detected value obtained at this time is compared with the initial position to determine the penetration. The amount of penetration of the measuring needle 2, that is, the degree of penetration is calculated. This calculated value is recorded in the recording section 44, and
It is displayed on the display 45.

According to this embodiment, the following effects can be obtained.

Contact between the penetration measuring needle 2 and the sample surface of the measurement sample 15 can be detected with high precision. For example, in the conventional method, it is difficult to detect contact between the penetration measuring needle 2 and the sample surface of the measurement sample 15, even by an expert. On the other hand, according to the present embodiment, even if the penetration measuring needle 2 penetrates into the sample surface of the measurement sample 15 by only about 0.1 mm, the penetration measurement needle 2 and the sample surface of the measurement sample 15 will overlap. contact can be detected. Furthermore, no skill is required for the measurement operation.

In addition, when detecting the penetration of the penetration measuring needle 2 using a dial gauge, in order to comply with standards such as JIS, it is necessary to change the entry time of the penetration measuring needle or use a correction method. had to be introduced. However, in this embodiment, the penetration measuring needle 2 is introduced into the measurement sample 15 in the same condition as in the JIS and other standards, so there is no need to change the entry time or introduce a correction formula. be.

6 and 7 show other embodiments of the clasp portion. In these figures, the clasp portion 61 has a support block 62, a cylinder hole 63 is provided in the support block 62, and a piston 64 is slidably held in the cylinder hole 63. Support block 62 and piston 64
are formed with through holes 65 and 66, respectively, the through hole 65 has a slightly larger diameter than the outer diameter of the needle holder 4, the through hole 66 has an even larger diameter than the through hole 65, and these through holes The needle holder 4 is loosely passed through 65 and 66.

A spring 67 is disposed at the bottom of the cylinder hole 63, and the spring 67 biases the piston 64 toward the outside of the cylinder hole 63, thereby shifting the center of both through holes 65 and 66 and supporting the needle holder 4. It is designed to be locked to a block 62. However, the piston 64 has the actuating member 3
6 are connected, and when the actuating member 36 moves the piston 64 by a predetermined amount toward the bottom of the cylinder hole 63 against the biasing force of the spring 67, both the through holes 65, 6
The needle holder 4 is moved in the direction in which the centers of the needle holders 6 and 6 coincide with each other.
is released from the support block 62 and can freely move up and down.

Even in an embodiment using such a clasp portion 61, the same effects as in the above-mentioned embodiment using the clasp portion 31 can be achieved.

In addition, although the embodiment in which the present invention is applied to penetration measurement has been described above, the present invention is not limited to this, and by appropriately changing the shape of the measuring needle 2, JIS- Grease durability can be measured based on K-2220 with the configuration other than the measuring needle being the same as in the above example, and further,
The penetration and penetration of petroleum wax can also be measured in the same way. In this way, penetration and penetration both measure the hardness of a substance, and there is no substantial difference between the names.

In addition, the linear direction displacement detector is a differential transformer 26.
However, the present invention is not limited to the differential transformer 26, and a linear encoder such as a capacitive type, an optical type, an electromagnetic type, etc. may be used.

Furthermore, the moving means for adjusting the vertical positional relationship between the penetration measuring needle 2 and the measurement sample 15 was configured so that the sample stage 14 could be raised and lowered by the second motor 22 in the above example. The stand 14 may be fixed, and the first motor 9 alone may bring the penetration measuring needle 2 into contact with the measurement sample 15 and loosen the flexible thread 5. In addition, when fixing the sample stage 14, the needle part 1, the strain gauge 6, the first motor 9, the differential transformer 25, the clasp part 3
A structure in which the parts including the first part can be moved as one to the sample stage 14 side may be used, but if the sample stage 14 side is movable, the amount of movement of the needle part 1 will be smaller and the flexible thread 5 will be subject to vibrations, etc. This is advantageous because it reduces the possibility of giving.

Moreover, the weight 3 of the needle part 1 is not fixed;
When the penetration measuring needle 2 is brought into contact with the sample surface, the load on the needle portion 1 by the weight 3 may be released to particularly improve the detection sensitivity of the contact by the strain gauge 6. In this case, the weight 3
is held in a separate holding mechanism, and when measuring penetration, is transferred to the needle part 1 so that the penetration can be measured with a predetermined weight.

Further, the operating procedure may be fully automated by being programmed in the memory 46, or may be a combination of manual operations.

[Effects of the Invention] As described above, according to the present invention, it is possible to provide a method and a measuring device for measuring penetration or penetration degree, which can easily obtain highly accurate measurement results without requiring special skill. .

[Brief explanation of drawings]

FIG. 1 is a front view showing the overall configuration of an embodiment in which the present invention is applied to a penetration measuring device, and FIGS. 2 and 3 are a plan view and front view showing an enlarged clasp portion of the embodiment. 4 is a block diagram showing the control system of the embodiment, FIG. 5 is a diagram showing changes in the output signal of the strain gauge in the embodiment, and FIGS. 6 and 7 are diagrams showing changes in the output signal of the strain gauge in the embodiment. FIG. 2 is a plan view and a partially sectional front view showing the clasp part. DESCRIPTION OF SYMBOLS 1... Needle part, 2... Needle for measuring penetration, 3... Weight, 4... Needle holder, 5... Flexible thread, 6... Strength gauge, 7... Rack, 8... ...Pinion,
9...First motor, 11, 12...Limit switch, 14...Sample stage, 15...Measurement sample, 16
... Constant temperature medium circulation path, 17 ... Circulation pump, 1
8... Constant temperature chamber, 19... Rack, 21... Pinion, 22... Second motor, 25... Differential transformer as linear displacement detector, 26... Coil,
31, 61... Clasp portion, 33... Gripping member, 34
... Rotation shaft, 35 ... Spring, 36 ... Operating member, 37 ... Link, 38 ... Drive shaft, 39 ...
...Solenoid, 40...Support, 41...CPU,
42, 43...A/D converter, 44...recording section,
45...Display, 46...Memory, 62...
...Support block, 63...Cylinder hole, 64...
Piston, 65, 66...through hole, 67...spring.

Claims (1)

[Claims] 1. A needle for measuring penetration or penetration with a constant load is suspended from a flexible thread connected to a strain gauge toward a measurement sample, and these measurement needles and the measurement sample are connected to each other. The contact between the measurement needle and the surface of the measurement sample when the measurement needle is gradually brought close to the surface of the measurement sample is controlled by the output signal of the strain gauge that changes based on the relaxation of the flexible thread caused by the contact between the measurement needle and the surface of the measurement sample. After that, the measuring needle is allowed to enter the measuring sample for a certain period of time with the flexible thread relaxed, and the amount of penetration of the measuring needle into the measuring sample at that time is related to the measuring needle. A method for measuring penetration or penetration, characterized by determining it from an output signal of a linear displacement detector. 2. A needle having a needle for measuring penetration or penetration and having a constant weight as a whole, a flexible thread hanging down from this needle, and a needle connected to the other end of the flexible thread. a strain gauge placed below the measuring needle; a moving means for adjusting the vertical positional relationship between the measuring needle and the measuring sample; A device for measuring penetration or penetration, comprising a linear displacement detector that detects the amount of displacement of a measuring needle when it is allowed to fall freely into a measurement sample for a certain period of time due to its weight. 3. The device for measuring penetration or penetration according to claim 2, wherein the linear displacement detector is comprised of a differential transformer.