JP4537524B2 - How to detect oil flowing in a pipe - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for detecting oil flowing through a pipe for detecting oil flowing through the pipe in a system in which oil flows through the light-transmitting pipe by air.
[0002]
[Prior art]
In general, as a system for flowing oil into a light-transmitting pipe by air, for example, an oil supply unit that supplies air to the pipe using air supplied from an air source and air supplied from the air source to the pipe The air supply unit that performs the lubrication is configured such that the oil supplied from the oil supply unit flows through the pipe with the air supplied from the air supply unit, and the oil mixed with the air is discharged from the nozzle provided at the end of the pipe. The system is known.
In such a system, the oil flowing through the pipe may be detected. As the detection method, conventionally, for example, as shown in FIG. 6, the pipe P is irradiated from the light emitting surface 4 of the light emitting unit 2 and the light emitting unit 2 that emits light from the light emitting surface 4 to the outside of the pipe P. There is a known method for detecting oil L flowing through a pipe P based on a change in the amount of light received by the light receiving unit 3.
In this method of detecting the oil flowing through the pipe, light is always emitted from the light emitting surface 4, so that when there is no oil L flowing through the pipe P, the light receiving surface 5 corresponds to the light emitted from the light emitting surface 4. When oil L flowing through the pipe P is present while receiving a predetermined amount of light, the light irradiated from the light emitting surface 4 passes through the oil L. At that time, the path of the light is refracted, the light is absorbed, etc. Therefore, the light receiving surface 5 cannot receive a predetermined amount of light. Therefore, the detection of the oil L flowing through the pipe P is determined by sensing a change in the amount of light received by the light receiving surface 5.
[0003]
[Problems to be solved by the invention]
By the way, in this conventional method of detecting the oil flowing through the pipe, as shown in FIG. 7, the oil L flowing through the pipe P is granular or rippled according to the air blowing pressure on the inner wall surface of the pipe P. When the oil L trajectory becomes unstable, the reflection or absorption of light with respect to the oil L varies, or when the oil L flows in a variety of shapes over the entire inner wall surface In some cases, a desired change in the amount of light cannot be applied to the light-receiving surface 5, and therefore there is a case where this flow cannot be detected even though the oil L is flowing. There was a problem that was getting worse.
[0004]
The present invention has been made in view of such problems. When a small amount of oil flows along with air in a pipe, the amount of detected oil is increased and the oil flows on a fixed track. An object of the present invention is to provide a method for detecting oil flowing through a pipe, in which the reflection and absorption of light can be made constant, and the oil flowing through the pipe can be reliably detected to improve detection accuracy. .
[0005]
[Means for Solving the Problems]
The technical means of the present invention for solving such problems is in a system in which oil flows along the inner wall surface of the pipe by air to a pipe having an inner wall surface that is translucent and forms a cross-sectional circle. A method for detecting oil flowing through a pipe for detecting oil flowing through the pipe, the light emitting unit irradiating light in the pipe on a circumference outside the pipe and centered on the center of one cross-sectional circle And a method of detecting the oil flowing through the pipe for detecting the oil flowing through the pipe based on the reception of the light from the light receiving unit. Bending the portion where the light emitting part and light receiving part of the pipe are located in an arc shape, and detecting the oil so that the oil mainly flows along the track of the inner wall surface having the smallest radius of curvature of the bent pipe. It has a configuration that.
According to this configuration, in the pipe, the portion where the light emitting portion and the light receiving portion are located is bent in an arc shape, so that the oil is along the track of the inner wall surface on the inner side having the smallest curvature radius of the bent pipe. It begins to flow mainly.
The reason why this flowing oil mainly flows along the track of the inner wall surface with the smallest radius of curvature of the pipe is that when the air passes through the arc bent part of the pipe, the wind pressure of the air is outside the bend of the inner wall surface. This is considered to be due to the fact that oil cannot adhere to the outside of the bend and the oil concentrates on the inside of the bend with a low wind pressure.
For this reason, the oil trajectory is specified in the pipe where the light emitting part and the light receiving part are provided, so that the oil particles are combined to increase the volume of the oil particles, and the light irradiated from the light emitting surface is The degree of passage through the oil particles increases, and the effects of light refraction, reflection, absorption, and the like due to the oil particles become constant. As a result, the change in the amount of light received by the light receiving surface when oil is flowing becomes substantially constant, so that the oil flowing through the pipe is reliably detected, and the detection accuracy is improved.
Further, since the threshold value for sensing oil can be increased, it becomes easier to detect a change in the amount of received light when the threshold value is increased.
[0006]
Further, if necessary, the light emitting surface normal perpendicular to the light emitting surface of the light emitting portion and passing through the center of the cross sectional circle and the light emitting surface perpendicular to the light receiving surface of the light receiving portion and An angle θ formed with a light-receiving surface normal passing through the center is set to be an inner angle range of 60 ° to 110 °, and between the inner-angle range of the light-emitting surface normal and the light-receiving surface normal, The light emitting part and the light receiving part are arranged with the orbit point of the orbit positioned.
When the light emitting unit and the light receiving unit are arranged in this manner, the change in the amount of light received by the light receiving surface can be reliably increased, and the threshold value can be further increased. In other words, the threshold value for detecting the change in the amount of received light becomes large, so that it becomes easy to detect the change in the amount of received light.
[0007]
Further, if necessary, an angle θ between the light emitting surface normal and the light receiving surface normal is set to 90 °, and a line connecting the center of the cross-sectional circle and the orbit point of the orbit on the cross-sectional circle is a reference line. As described above, the angle α formed by the reference line and the light emitting surface normal is set to 20 ° to 80 °.
If the angle θ is 90 °, the rate of light passing through the oil reaching the light receiving surface is substantially halved, and the amount of light received on the light receiving surface varies greatly depending on the presence or absence of oil flowing through the pipe. If the angle θ is smaller than 90 °, the amount of light received increases, but the rate at which light passing through the oil reaches the light receiving surface increases too much, and the change in the amount of light received on the light receiving surface due to the presence or absence of oil becomes small. Further, if the angle θ is larger than 90 °, the amount of received light decreases, and the rate at which the light passing through the oil reaches the light receiving surface decreases, so the change in the amount of received light on the light receiving surface due to the presence or absence of oil also decreases.
That is, when the angle θ is 90 ° at which a moderate amount of received light can be obtained and the change in the amount of received light on the light receiving surface due to the presence or absence of oil can be increased, the light receiving unit can easily detect the change in the amount of received light. Detection accuracy is improved. At this time, if the angle α is set to 20 ° to 80 °, the change in the amount of light received on the light receiving surface due to the presence or absence of oil can be increased, and the threshold for sensing the change in the amount of received light becomes large. Therefore, it becomes easy to sense a change in the amount of received light.
Furthermore, if necessary, the light emitting surface of the light emitting part has a width smaller than the diameter of the pipe.
As the width of the light emitting surface is reduced, the degree to which light emitted from the light emitting surface passes through oil increases, and the change in the amount of light received on the light receiving surface greatly depends on the presence or absence of oil. Since the threshold value for detecting the change in the amount of received light increases, it becomes easy to detect the change in the amount of received light.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a method for detecting oil flowing through a pipe according to an embodiment of the present invention will be described with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected and demonstrated to the same thing as the above.
The method for detecting oil flowing through a pipe according to the embodiment of the present invention shown in FIG. 1 is, for example, in an oil supply system S for supplying a minute amount of oil L to a supply unit 17 using air as shown in FIG. This is realized using the detection device 1.
The oil supply system S includes an oil supply unit 13 including a plunger pump 13a that is driven by air supplied from an air source 10 to a passage pipe 12 via a regulator 11 and discharges a constant amount of oil L, and air that reaches the oil supply unit 13. An air supply line 14 that is branched from the line and supplies air from the air source 10 via another regulator 11, an oil line 15 of oil discharged from the plunger pump 13 a of the oil supply unit 13, and the air A three-way joint-like mixing block 16 that is connected to the supply pipe line 14 to allow the oil and air to be mixed and fed, and the mixed oil flows from the mixing block 16 to the oil supply unit 17. The pipe P is configured to include a pipe 18 and a nozzle 18 that is connected to the tip of the pipe P and ejects oil L to the supply unit 17.
In this oil supply system S, the amount of oil supplied at one time of the plunger pump 13a is, for example, 0.01 to 0.05 cc and is intermittently operated with a pause of 1 minute to 10 minutes.
The air pressure is set to, for example, 0.1 MPa to 0.5 MPa.
Further, as shown in FIGS. 1, 3 to 5, the pipe P has a translucent inner wall surface 6 that forms a cross-sectional circle Q, for example, an inner diameter of 2.5 mm (an outer diameter of 4 mm). It consists of a resin pipe such as a tube.
[0009]
And the detection apparatus 1 is provided in the predetermined position of the pipe P of the oil supply system S. FIG. As shown in FIGS. 3 to 5, the detection device 1 includes a light emitting unit that irradiates light into the pipe P on the circumference outside the pipe P and centered on the center O of one cross-sectional circle Q. 2 and a light receiving unit 3 that receives light emitted from the light emitting unit 2 and passed through the pipe P, and detects oil L flowing through the pipe P based on light reception by the light receiving unit 3.
As shown in FIG. 1, the light emitting unit 2 includes a light source including a light emitting diode (not shown) inside, and continues to irradiate light into the pipe P through the light emitting surface 4 while the fueling system S is in operation. . The light receiving unit 3 includes a photosensitive element therein and senses light through the light receiving surface 5. In the light receiving unit 3, the amount of light received when the oil L is not flowing in the pipe P is set as a reference value (for example, 100), and a threshold value (for example, 100 ± 30) is set for the reference value. By setting the threshold value, the light receiving unit 3 is configured to detect the oil L when the amount of received light is 130 or more or less than 70.
The light emitting surface 4 of the light emitting unit 2 is configured to have a width smaller than the diameter of the pipe P.
3 to 5, the light emitting surface 4 of the light emitting unit 2 is shown larger than the diameter of the pipe P for convenience of explanation.
[0010]
Next, a method for detecting the oil flowing through the pipe according to the embodiment of the present invention realized by using the detection device 1 will be described in detail.
The detection method according to the embodiment is an oil detection method for detecting the oil L flowing through the pipe P. In this detection method, the positions of the light emitting unit 2 and the light receiving unit 3 of the pipe P as shown in FIG. The portion to be bent is bent in an arc shape so that the oil L is mainly flowed along the track A of the inner inner wall surface 6 having the smallest curvature radius of the pipe P bent. In this case, the radius of curvature may be determined as appropriate, and the bending direction may be any direction up, down, left, or right without being limited by the direction of gravity.
The reason why this flowing oil L mainly flows along the track A of the inner inner wall surface 6 with the smallest radius of curvature of the pipe P is that when the air passes through a place where the pipe P is bent in an arc shape, the wind pressure of the air is internal. Since it acts strongly on the outside of the bend of the wall surface 6, it is considered that the oil L cannot adhere to the outside of the bend and the oil L concentrates on the inside of the bend with a low wind pressure.
[0011]
In the detection method according to the embodiment of the present invention, the positional relationship between the light emitting unit 2 and the light receiving unit 3 is determined as follows.
As shown in FIGS. 3 to 5, the light emitting unit 2 and the light receiving unit 3 are perpendicular to the light emitting surface 4 of the light emitting unit 2 and pass through the center O of the cross-sectional circle Q of the inner wall surface 6. The angle θ between N and the light-receiving surface normal M that is perpendicular to the light-receiving surface 5 of the light-receiving portion 3 and passes through the center O of the cross-sectional circle Q of the inner wall surface 6 is in an inner angle range of 60 ° to 110 °. In addition, the trajectory point a of the trajectory A on the cross-sectional circle Q is positioned between the inner angle θ range of the light emitting surface normal N and the light receiving surface normal M. FIG. 3 shows a case where the angle θ is 60 °, and FIG. 4 shows a case where the angle θ is 110 °. FIG. 5 shows a case where the angle θ is 90 °.
[0012]
As shown in FIG. 5, when the angle θ formed by the light emitting surface normal N and the light receiving surface normal M is set to 90 °, the center O of the cross-sectional circle Q and the trajectory point a of the trajectory A on the cross-sectional circle are represented by More preferably, the angle α formed between the reference line X and the light emitting surface normal N is set to 20 ° to 80 °, with the connecting line as the reference line X.
Further, as shown in FIGS. 3 to 5, in particular, the positional relationship between the light emitting unit 2 and the light receiving unit 3 is such that the light emitting surface 4 and the light receiving surface 5 are in contact with the pipe P.
[0013]
Therefore, according to the oil supply system S, when air is supplied from the air source 10 and oil is discharged from the plunger pump 13a of the oil supply unit 13, the oil and air are mixed in the mixing block 16, and the air is mixed. The oil that has passed through the pipe P reaches the oil supply unit 17 and is ejected from the nozzle 18.
In this state, the detection apparatus 1 always detects the oil L flowing through the pipe P, and this detection makes it possible to recognize a system abnormality.
According to the oil detection method using this detection device 1, as shown in FIG. 1, in the pipe P, the portion where the light emitting unit 2 and the light receiving unit 3 are located is bent in an arc shape. Since the pipe P mainly flows along the track A of the inner inner wall surface 6 having the smallest curvature radius, the track A of the oil L is specified, and the track A is specified. As a result, the oil L grains are combined to increase the volume of the oil L grains, and the degree to which the light emitted from the light emitting surface 4 passes through the oil L grains increases, and the light L is refracted, reflected, and absorbed by the oil L grains. The influence of the action and the like can be made constant, so that the oil L flowing through the pipe P can be reliably detected, and the detection accuracy can be improved.
[0014]
That is, the positional relationship between the light emitting unit 2 and the light receiving unit 3 is set so that the angle θ is within an inner angle range of 60 ° to 110 ° and between the inner angle θ range of the light emitting surface normal N and the light receiving surface normal M. By positioning the trajectory point a of the trajectory A on the cross-sectional circle Q, the degree of passage of the light irradiated from the light emitting surface 4 through the oil L increases, and the amount of light received when the oil L is not flowing, A large difference (change in the amount of received light) occurs between the amount of received light when L is flowing. By increasing the change in the amount of received light, the threshold for sensing the change in the amount of received light can be increased, and the detection of the oil L can be facilitated. In other words, since the threshold value is increased, it is possible to sense a change in the amount of received light using a light receiving element with low sensitivity.
[0015]
In this case, since the light emitting surface 4 of the light emitting unit 2 is configured to have a width smaller than the diameter of the pipe P, the light emitted from the light emitting surface 4 passes through the oil L on the track A. Thus, the light emitting surface 4 was positioned. The amount of light emitted from the light emitting surface 4 passes through the oil L and the change in the amount of light on the light receiving surface 5 greatly depends on the presence or absence of the oil L. Since the change in the amount of received light increases, the light receiving unit 3 can easily detect the change, and the detection accuracy of the oil L can be improved. Further, if the area of the light emitting surface 4 is reduced, the amount of heat consumed is reduced at the same illuminance ratio.
Further, as shown in FIGS. 3 to 5, the light emitting surface 4 of the light emitting unit 2 is in contact with the pipe P, and the light receiving surface 5 of the light receiving unit 3 is also in contact with the pipe P. Since the degree to which the light emitted from the light passes through the oil L increases and the change in the amount of light received by the light receiving surface 5 increases, the detection accuracy of the oil L can be improved.
[0016]
In addition, as shown in FIG. 5, when the angle θ formed by the light emitting surface normal N and the light receiving surface normal M is set to 90 °, the center O of the cross-sectional circle Q and the trajectory point a of the trajectory A on the cross-sectional circle If the angle α formed by the reference line X and the light emitting surface normal N is set to 20 ° to 80 ° with the line connecting the two lines as the reference line X, the oil flowing through the pipe P has an angle θ of 90 °. It was found that the change in the amount of received light with or without L can be increased. If the angle θ is smaller than 90 °, the amount of received light increases, but the rate at which light passing through the oil L reaches the light receiving surface 5 becomes too large, and the change in the amount of received light due to the presence or absence of the oil L becomes small. Further, if the angle θ is larger than 90 °, the amount of received light decreases, and the rate at which the light passing through the oil L reaches the light receiving surface 5 decreases, so that the change in the amount of received light due to the presence or absence of the oil L also decreases. Thus, the change in the amount of received light on the light receiving surface 5 can be maximized when the angle θ is 90 °.
Further, when the angle θ is 90 °, the change in the amount of light received by the light receiving surface 5 of the light emitted from the light emitting surface 4 that has passed through the oil L becomes larger by setting the angle α to 20 ° to 80 °. .
If such an arrangement condition is used, a large difference can be generated in the amount of light received by the light receiving surface 5 between when the oil L is flowing and when the oil L is flowing. Therefore, the oil L can be reliably detected using a normal photosensitive element without using an expensive photosensitive element with high sensitivity.
[0017]
In the detection method of the oil flowing through the pipe according to the above embodiment, the oil L is detected by changing the amount of light received by the light receiving unit 3 when the oil L flows through the pipe P. By adjusting the positional relationship with the light receiving unit 3 and increasing the amount of light received by the light receiving unit 3 when the oil L flows through the pipe P, the oil is increased or decreased to decrease the amount of oil. L can also be detected.
[0018]
【The invention's effect】
As described above, according to the method for detecting oil flowing through a pipe according to the present invention, the portion where the light emitting portion and the light receiving portion of the pipe are located is bent in an arc shape, and the inner wall surface of the bent pipe having the smallest radius of curvature is provided. A small amount of oil mainly flows along the trajectory of the oil, and light is applied to the trajectory of the inner wall surface through which the oil flows, and the amount of light received by the light receiving unit is constantly changed by the action of the light passing through the oil. Therefore, the oil flowing through the pipe can be reliably detected by sensing the change.
In addition, the light emitting surface normal perpendicular to the light emitting surface of the light emitting unit and passing through the center of the cross sectional circle of the inner wall surface, and the center of the cross sectional circle of the inner wall surface perpendicular to the light receiving surface of the light receiving unit The angle θ formed with the light-receiving surface normal passing through is set to an inner angle range of 60 ° to 110 °, and the orbit point of the orbit on the cross-sectional circle is positioned between the inner angle side of the light-emitting surface normal and the light-receiving surface normal. Thus, when the light emitting unit and the light receiving unit are arranged, the change in the amount of light received by the light receiving surface can be surely increased, and the threshold value can be further increased, so that the change in the amount of received light is detected. Therefore, the oil detection accuracy can be improved.
[0019]
Further, the angle θ formed between the light emitting surface normal and the light receiving surface normal is set to 90 °, and the reference line and the light emitting surface normal are defined with reference to a line connecting the center of the cross-sectional circle and the orbital point of the orbit on the cross-sectional circle. When the angle α is set to 20 ° to 80 °, an appropriate amount of received light that can increase the change in the amount of light received on the light receiving surface due to the presence or absence of oil is obtained, and the light receiving unit senses the change. Therefore, the oil detection accuracy can be improved.
Furthermore, when the light emitting surface of the light emitting part is made smaller than the diameter of the pipe, the degree of light passing from the light emitting surface increases through oil, so the change in the amount of light on the light receiving surface is the presence or absence of oil. Since the light receiving unit easily senses the change, the oil detection accuracy can be improved.
[Brief description of the drawings]
FIG. 1 is a diagram showing a method for detecting oil flowing through a pipe according to an embodiment of the present invention.
FIG. 2 is a diagram showing an example of an oil supply system in which a method for detecting oil flowing through a pipe according to an embodiment of the present invention is used.
FIG. 3 is a cross-sectional view showing a method for detecting oil flowing through a pipe according to an embodiment of the present invention, and shows a case where θ is 60 °.
FIG. 4 is a cross-sectional view showing a method for detecting oil flowing through a pipe according to an embodiment of the present invention, showing a case where θ is 110 °.
FIG. 5 is a cross-sectional view showing a method for detecting oil flowing through a pipe according to an embodiment of the present invention.
FIG. 6 is a cross-sectional view showing an example of a conventional method for detecting oil flowing through a pipe.
FIG. 7 is a cross-sectional view showing a state of oil flowing through a straight pipe.
[Explanation of symbols]
P Pipe L Oil N Light emitting surface normal M Light receiving surface normal Q Cross-sectional circle O Center α Angle θ Angle X Reference line A Orbit a Orbit point 1 Detector 2 Light emitting unit 3 Light receiving unit 4 Light emitting surface 5 Light receiving surface 6 Inner wall surface

Claims (4)

This is a method for detecting oil flowing through a pipe, which detects oil flowing through the pipe in a system in which oil flows along the inner wall surface of the pipe by air to a pipe having a translucent inner wall surface that forms a cross-sectional circle. And
A light emitting unit for irradiating light into the pipe on the outer periphery of the pipe and centering on the center of one cross-sectional circle; and a light receiving unit for receiving light emitted from the light emitting unit and passing through the pipe In the method of detecting the oil flowing through the pipe for detecting the oil flowing through the pipe based on the reception of the light of the light receiving unit,
Bending the portion of the pipe where the light emitting portion and the light receiving portion are located in an arc shape, and detecting the oil so that the oil flows mainly along the track of the inner wall surface having the smallest radius of curvature of the pipe. A method for detecting oil flowing through a pipe, characterized in that: A light emitting surface normal perpendicular to the light emitting surface of the light emitting portion and passing through the center of the cross sectional circle, and a light receiving surface normal perpendicular to the light receiving surface of the light receiving portion and passing through the center of the cross sectional circle And an orbital point of the orbit on the cross-sectional circle between the inner angle range of the light emitting surface normal and the light receiving surface normal. 2. The method for detecting oil flowing through a pipe according to claim 1, wherein the light emitting part and the light receiving part are arranged in a position. An angle θ between the light emitting surface normal and the light receiving surface normal is set to 90 °,
The line α connecting the center of the cross-sectional circle and the trajectory point of the orbit on the cross-sectional circle is used as a reference line, and the angle α formed by the reference line and the light emitting surface normal is set to 20 ° to 80 °. A method for detecting oil flowing through a pipe according to claim 2. 4. The method for detecting oil flowing in a pipe according to claim 2, wherein the light emitting surface of the light emitting portion is configured to have a width smaller than the diameter of the pipe.

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