JP6248645B2 - Pipe liquid detection sensor - Google Patents

Description

  The present invention relates to a pipe liquid detection sensor that detects the presence or absence of liquid in a cylindrical tube such as a pipe or tube without touching the liquid.

  Various liquid detection sensors have been devised that automatically and stably detect whether liquid is present in a cylindrical tube such as a pipe or tube having a circular cross section from the outside. A tube made of a material that transmits light is irradiated with light from the outside at the light emitting portion, and the light from the light emitting portion hits the inner wall surface of the tube, and the reflected light enters the light incident portion. There is a reflection-type liquid detection sensor having a configuration in which the light emission portion and the light incidence portion are arranged at an equal angle with respect to the normal direction of the reflection surface of the inner wall of the tube. (For example, see Patent Document 1).

  In addition, it has been considered to change the arrangement relationship between the light emitting portion and the light incident portion so that an optimum state is obtained even when the tube diameters are different (for example, see Patent Document 2).

  However, as for the method of fixing the liquid detection sensor, as shown in Patent Document 2, an ordinary form such as mounting with a pipe sandwiched between two screws is adopted, and workability is included. The details were not examined. It has been a challenge to detect the presence or absence of liquid stably.

  When fixing an object to a cylindrical tube, a configuration in which a tube is sandwiched between a main body and a plate material formed with a U-shaped groove and both sides separated by the U-shaped groove are tightened with screws is a very common fixing method. In this case, the depth of the U-shaped groove is set to be shallower than half of the diameter of the sandwiched tube, and it is required to tighten with the same force with two screws. The work of tightening the two screws alternately little by little while maintaining the gap between the main body and the plate material evenly is considerably troublesome.

Japanese Patent Laid-Open No. 4-66820

JP 2004-45319 A

  The problem to be solved is that when fixing the liquid detection sensor to the pipe, it is necessary to screw at least two places, and workability is poor. One person supports one hand while the other hand holds the screw. It is difficult to stop.

  In the present invention, the tube is sandwiched between V-shaped grooves provided in the main body and the plate material. A bearing portion having a long bearing hole is formed on one side of the plate material, and the shaft is supported by a support shaft provided on the support portion on the main body side so that the rotating shaft can be moved. A screw fixing mechanism is provided on the other side of the plate material, and a screw that penetrates the plate material is fitted into a nut embedded in the main body, and both sides of the nut (in the direction along the V-shaped groove) can be made of silicon rubber or the like. The elastic material is embedded in a shape that protrudes toward the plate material side, and an appropriate frictional force is generated between the plate material, the V-shaped groove of the main body, and the sandwiched pipe as the screw is turned around. . For this reason, the structure is fixed only by tightening one screw.

  Since the pipe liquid detection sensor of the present invention has a structure that is fixed only by tightening one screw, it can be easily attached by one person's work. Since one screw has a structure that is fastened and fixed in a direction to sandwich the tube, a plurality of sensors can be installed side by side. Moreover, the workability is the same as when a single product is attached. Since one screw is tightened and fixed in the direction to sandwich the tube, there is an advantage that workability does not change regardless of the operator's dominant arm. Further, if it is used for a lightweight sensor, it can be directly fixed to the pipe, and it is not necessary to fix the sensor body to a special place. Since the plate that sandwiches the tube is supported by a rotating shaft that can move relative to the main body, the diameter of the tube to which the pipe liquid detection sensor can be fixed can have a certain width, and one unit The range of pipe diameters applicable to pipe liquid detection sensors has been expanded.

FIG. 1 is an explanatory view showing a state in which a pipe liquid detection sensor is fixed to a pipe. FIG. 2 is an explanatory view showing a state in which the case cover is removed from the pipe liquid detection sensor. FIG. 3 is an AA enlarged sectional view of FIG. 1, and is an explanatory view showing a state in which the case cover is coupled to the sensor body.

  The purpose of enabling the pipe liquid detection sensor to be easily attached to a transparent pipe of φ1.6mm to φ2.6mm by one person's work with the minimum number of parts and without compromising the fixing strength to the pipe did.

  FIG. 1 is an explanatory view showing a state in which the pipe liquid detection sensor of the present invention is fixed to a pipe. S is a pipe liquid detection sensor, and P is a cylindrical tube (hereinafter referred to as a pipe). The pipe P is fixed so as to be sandwiched between the main body 10 of the pipe liquid detection sensor S and the case cover 30. Reference numerals 26 and 27 denote mounting holes for bringing the back surface of the sensor into contact with a surface to be fixed such as a wall surface and fixing the fixing through a fixing screw (not shown).

  A connection portion between the sensor main body 10 and the case cover 30 is formed on the right side surface facing the pipe liquid detection sensor. As for the connection part, two bearing elongated holes (33 and 34) respectively formed in two bearing parts (31 and 32) provided on the right side of the case cover 30 are provided above and below the support part G of the main body 10. Are supported by two support shafts (see 11 and 12 in FIG. 2). Reference numeral 36 denotes a case cover fixing screw, and reference numeral 21 denotes a cord incorporating a power supply line and a signal output line. Both the sensor body 10 and the case cover 30 are manufactured by resin molding.

  FIG. 2 is an explanatory view showing a state in which the case cover 30 is removed from the pipe liquid detection sensor S. The support portion G on the right side of the main body 10 has a shape protruding from the front side of the sensor main body 10 by the thickness of the case cover 30, and a support shaft 11 and a support shaft 12 are formed above and below it. Yes. The support shaft 11 and the support shaft 12 are cut obliquely toward the front side, and two bearing elongated holes (33 and 34) formed in the bearing portions (31 and 32) of the case cover 30 respectively. The case cover 30 is united by being pushed into the sensor body 10 so as to be in close contact therewith. The front side provided on the support shaft 11 and the support shaft 12 in the process in which the two bearing portions (31 and 32) provided on the right side of the case cover 30 push the case cover 30 into close contact with the sensor body 10 side. Contacted with the surface cut obliquely toward the surface and expanded in the vertical direction, the edges of the two bearing elongated holes (33 and 34) formed in the respective bearings over the tip of the support shaft, To unite. The support part G is also provided on the support shaft 11 and the support shaft 12 with a sloped machining part (13 and 14) cut obliquely toward the front side, following the face cut obliquely toward the front side. , And the operation of bringing the case cover 30 into close contact with the sensor body 10 side and combining them is performed more smoothly.

Reference numeral 17 denotes a light emitting part, and 18 denotes a light incident part. The light emitted from the light emitting portion 17 hits the inner wall surface of the pipe set here, and the light reflected there enters the light incident portion. The positional relationship between the light emitting part and the light incident part is such that each of them is inclined at substantially the same angle with respect to the normal direction of the reflecting surface of the inner wall of the pipe. 22 is a sensitivity adjusting volume, 23 is an operation indicator lamp, and 24 is a stability indicator lamp. A pipe liquid detection sensor is attached to the pipe, and the sensitivity adjustment volume is turned until the stability indicator lamp 24 is turned on with no liquid in the pipe. Next, let the liquid pass through the pipe and check whether the operation indicator lights. Appropriately set the threshold value (amount of light incident on the light incident portion) when the stability indicator lamp 24 is turned on and the threshold value (amount of light incident on the light incident portion) when the operation indicator light is turned on. For example, the above operation check is a guarantee that the pipe liquid detection sensor functions stably. When liquid is present in the pipe, the amount of reflected light at the reflecting surface of the inner wall of the pipe decreases by the amount of light that is refracted toward the liquid and increases, so it is refracted by the presence of liquid. If the arrangement relationship between the light emitting part and the light incident part such that the amount of outgoing light increases is adjusted to other setting states, the operation of the pipe liquid detection sensor is stabilized accordingly.

Reference numerals 19 and 20 denote cylindrical elastic materials made of silicon rubber, and these elastic materials are embedded in a shape protruding from the main body 10 toward the front side. The case cover fixing screw 36 is contracted as it is turned into the nut 16 built in the sensor body 10. Since the elastic material 19 and the elastic material 20 are arranged at the same height on both sides of the case cover fixing screw 36, the case cover 30 is connected to the main body 10 according to the tightening of the case cover fixing screw 36. It moves almost in parallel while keeping the distance constant.

Next, it will be described in detail that the case cover is coupled to the sensor body so that the rotation shaft can move. FIG. 3 is an AA enlarged sectional view of FIG. 1, and is an explanatory view showing a state in which the case cover is coupled to the sensor body. What is indicated by a broken line is a case cover in a state where the case cover 30 is rotated from the main body 10 of the pipe liquid detection sensor S around the support shaft and opened. Reference numeral 36 denotes a case cover fixing screw, and reference numeral 16 denotes a nut embedded in the main body 10. The pipe P is placed along the V-shaped groove 15 of the main body 10 and the case cover 30 is brought close to the main body 10 so that the V-shaped groove 35 of the case cover 30 contacts the pipe P. Then, the tip of the case cover fixing screw 36 is fitted into the nut 16 and tightened. Then, the case cover 30 moves substantially in parallel while keeping the distance from the main body 10 constant, and a force is applied between the V-shaped groove 35 of the case cover 30 and the pipe P, and a frictional force is generated.

FIG. 3 shows a state in which a pipe P having a diameter of about 2 mm is sandwiched, and the case cover support shaft 12 is positioned substantially at the center of the bearing elongated hole 34 provided in the bearing portion 32 and is stopped. When a pipe P having a diameter of 1.6 mm, which is the minimum value of the pipe diameter to be attached, is sandwiched, the main body 10 and the case cover 30 are stopped in a state of close contact, and the case cover support shaft 12 is supported by the bearing portion 32. It will be located above the bearing long hole 34 provided in. When a pipe P having a diameter of 2.6 mm, which is the maximum value of the pipe diameter to be attached, is sandwiched, the main body 10 and the case cover 30 are stopped in a state farther than the state shown in FIG. Therefore, it is located below the bearing slot 34 provided in the bearing portion 32.

In this way, the case cover is coupled to the sensor body so that the rotation shaft can move. Therefore, even if the diameter of the sandwiched pipe is φ1.6 mm or φ2.6 mm, the force is almost the same. The main body comes into contact with the V-shaped groove of the case cover, and the fixing strength is kept constant. The light emitted from the light source (not shown) through the optical fiber FL is emitted from the light emitting unit 17 toward the pipe P, and the light incident on the light incident unit 18 passes through the optical fiber FR to the light receiving element (not shown). Reach.

If it is adopted as a lightweight sensor, it can be directly fixed to a small-diameter pipe. For example, it can be applied to a medical sensor that is attached to a drip tube in a suspended state and detects the end of the drip solution.

S pipe liquid detection sensor P pipe 10 main body 11 of pipe liquid detection sensor S support shaft 12 support shaft 13 inclined processing portion 14 inclined processing portion 15 V-shaped groove 17 light emitting portion 18 light incident portion 19 elastic material 20 elastic material 21 code 22 Volume 23 Operation indicator lamp 24 Stability indicator lamp 26 Mounting hole 27 Mounting hole 30 Case cover of pipe liquid detection sensor S 31 Bearing portion 32 Bearing portion 33 Bearing elongated hole 34 Bearing elongated hole 35 V-shaped groove 36 Case cover fixing screw FL Optical fiber FR optical fiber

Claims (2)

  A tube made of a material that transmits light is irradiated with light from the outside at the light emitting portion, and the light from the light emitting portion hits the inner wall surface of the tube, and the reflected light enters the light incident portion. Whether or not there is liquid in the tube so that the arrangement relationship between the light emitting portion and the light incident portion is inclined at an equal angle with respect to the normal direction of the reflecting surface of the inner wall of the tube. In the reflection type pipe liquid detection sensor for detecting the outside from the outside, the tube formed of the light transmitting material is configured to be sandwiched between V-shaped grooves provided in the sensor main body and the plate material, and one of the plate materials includes: A bearing portion having a bearing long hole is formed, and the bearing shaft is supported by a support shaft provided on the support portion on the sensor body side so that the rotation shaft can be moved. A screw that penetrates the plate is embedded in the sensor body. The elastic material is embedded in a shape protruding to the plate material side on both sides in the direction along the V-shaped groove of the nut, and the plate material is attached to the body of the main body as the nut is turned around. A pipe liquid detection sensor, wherein a pipe sandwiched between V-shaped grooves is pushed in, and a force is applied between a plate and a pipe and between the pipe and the main body to generate a frictional force. 2. The pipe liquid detection sensor according to claim 1, wherein a support shaft provided in the support portion on the sensor body side is cut obliquely toward the front side.

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