JP7488525B2 - Sensor fixture and fluid control device - Google Patents

Description

The present invention relates to a sensor fixture, and in particular to a sensor fixture that can securely and easily attach a temperature sensor to a pipe or a fluid control device, and a fluid control device equipped with the sensor fixture.

Sensors attached to pipes and fluid control devices, especially temperature sensors, have a small diameter and may come off if not attached securely, so various sensor fixing devices have been proposed. When measuring the temperature of a fluid in a fluid control device equipped with multiple gas lines, a small hole for attaching the sensor is drilled in the flow path block, a half-split support member is fixed to the actuator part of the fluid control device, for example, an on-off valve, a slit is provided on the mating surface of the mating protrusion, the sensor wiring part is sandwiched in the slit and tightened with a screw, and the tip of the sensor part is inserted into the small hole for attaching the sensor to fix the sensor (see, for example, Patent Document 1).

In addition, when attaching to a pipe, a simple method is often used, such as placing the sensor part on the circumference of the pipe where the measurement is to be performed and wrapping it with wire to secure it.

Patent Publication No. 6240661

However, the sensor fixture disclosed in Patent Document 1 requires machining of a thick metal material to match the size of the actuator, which is costly. In addition, when attaching the sensor to the pipe, the sensor is fixed by wrapping it around the pipe, and the metal wires come into contact with each other in large numbers, which can prevent accurate temperature measurement. There is also the risk of the sensor falling off if the sensor is not fixed sufficiently. Another problem is that using wires or the like as a fixture increases the number of contact points between the fixture and the pipe or sensor, which can lead to a deterioration in measurement accuracy due to heat conduction from the fixture.

The present invention was made in consideration of these points, and its purpose is to provide a sensor fixture that can fix a rod-shaped sensor and the wiring extending from the sensor to a cylindrical member with a simple structure, and a fluid control device equipped with the sensor fixture.

The sensor fixture according to the present invention, which has been made to solve the above problems, comprises:
A sensor fixture for mounting a sensor on a cylindrical object, comprising:
a main body formed by bending a flat plate-like member into a U-shape so that the inner surface distance between both ends is substantially the same as the diameter of the object;
A cylindrical body having a length substantially equal to the diameter of the object and having screw holes formed on both end surfaces;
The screw is a countersunk screw having a seat surface formed in a truncated cone shape that is screwed into the screw hole,
The body is configured with mounting holes at both ends through which the flat head screws that screw into the screw holes of the cylindrical body are inserted. The mounting holes are larger than the screw diameter and smaller than the maximum outer diameter of the head of the flat head screw, and are preferably about the outer diameter of the middle position of the frustum of the cone on the head seat side.

This sensor fixing device has a truncated cone-shaped seating surface of the flat head screw that fits along the mounting hole as the flat head screw is tightened into the cylindrical body, firmly fixing the sensor placed between the inside of the U-shaped bent part of the plate and the surface of the object, such as a pipe that is the measurement target.

In this case, the U-shaped bent portion of the plate can have a defect formed around the entire circumference of the bent portion.

In addition, a fluid control device according to the present invention, which is made to solve the same problem, comprises:
A fluid control device;
a flow path block in which a flow path is formed inside the flow control device;
Among fluid control devices, a sensor fixing device as described in claim 1 or claim 2 is provided on the actuator of a fluid control device having a cylindrical actuator, a sensor part is attached to a sensor mounting hole formed in a flow path block, and the sensor wiring is fixed to the surface of the actuator with the sensor fixing device.

According to the present invention, by determining the center distance of the mounting holes located at both ends in a flat plate state from the outer diameter of the sensor or the wiring extending from the sensor and the outer diameter of the object, such as a pipe, to which the sensor fixture is attached, it is possible to easily manufacture a sensor fixture that can firmly fix the sensor or the wiring extending from the sensor to a cylindrical member.

1 is a partially cutaway perspective view showing an outline of a state in which a sensor fixture according to an embodiment of the present invention is attached to a pipe. FIG. 11 is a partially cutaway perspective view showing a procedure for attaching the sensor fixture to a pipe. FIG. These are cross-sectional views showing the procedure for attaching the sensor fixture to piping: (a) shows the sensor being placed between the piping and the sensor fixture main body, with the cylindrical body positioned between both ends of the main body; (b) shows the flat head screw being inserted through the mounting hole in the main body and temporarily fixed into the screw hole in the cylindrical body; and (c) shows the flat head screw being tightened, with the cylindrical body pressing the piping towards the sensor, and the sensor being clamped and fixed between the inside of the curved surface of the main body and the outer circumferential surface of the piping. FIG. 11 is a plan view showing a flat state of the main body of the sensor fixture before bending. 13A and 13B are a side view and a perspective view, respectively, showing another embodiment of the main body of the sensor fixture. 13 is a partially cutaway perspective view of a fluid control device in which the sensor fixing device is attached to a fluid control device. FIG.

The following describes in detail the embodiments of the present invention with reference to the drawings. Note that the following embodiments are essentially preferred examples and are not intended to limit the scope of the present invention, its applications, or its uses. In addition, the term "cylindrical" used in this specification includes not only hollow cylinders, but also solid cylinders.

<Embodiment 1>
1 to 4 show a first embodiment of the present invention.

This sensor fixture 1 is used to secure various sensors, such as a temperature sensor or wiring extending from a temperature sensor, to fluid control equipment or piping. In this embodiment, an example is shown in which a temperature sensor S is attached to a piping P.

This sensor fixture 1 is a sensor fixture 1 for attaching a temperature sensor to a cylindrical object, which in this embodiment is a pipe P, and is composed of a main body 2 in which a flat plate-shaped member is bent into a U-shape so that the inner surface distance between both ends is approximately the same as the diameter of the object, a cylindrical body 3 with screw holes 3a formed on both end faces with a length approximately the same as the diameter of the object, and a flat head screw 4 with a seat surface 4b that screws into the screw hole 3a and has a truncated cone shape. At both ends of the U-shaped bent main body 2, mounting holes 2a are opened through which the threaded portion 4a of the flat head screw 4 that screws into the screw hole 3a of the cylindrical body 3 is inserted. The mounting hole 2a is configured to be larger than the screw outer diameter of the flat head screw 4 and smaller than the maximum outer diameter of the head of the flat head screw 4, and is preferably configured to be, for example, approximately the outer diameter at the midpoint of the truncated cone periphery of the seat surface 4b of the head.

[Main unit]
As shown in FIG. 4, the main body 2 consists of a long flat plate with mounting holes 2a at both ends and a notch 2b in the center, and is bent into a U-shape so that the inner surface distance between both ends is approximately equal to the outer diameter of the pipe P to which the sensor is attached.

The center-to-center distance L of the mounting holes 2a, 2a can be easily calculated from the outer diameter of the sensor S, the outer diameter of the pipe P, and the outer diameter of the cylindrical body 4. By matching this center-to-center distance L and the inner R dimension when bent with the radius of the pipe P, a highly accurate sensor fixing device 1 can be easily manufactured.

Furthermore, as shown in the cross-sectional view of FIG. 3, the mounting hole 2a may be opened cylindrically, or may be machined as a countersunk hole to match the conical seat of the countersunk screw 4 (the seat angle of the countersunk head is 90°).
In line with

[Cylindrical body]
In this embodiment, a solid metal cylinder is used as the cylindrical body 3, but the material is not particularly limited. The screw holes 3a formed on both end faces may be pilot holes that penetrate the body and have threads engraved along the entire length as shown in the figure, but they do not need to be pilot holes of a predetermined depth that penetrate the body.

The dimensions of the cylindrical body 3 are that the length is equal to the outer diameter of the pipe P, and the outer diameter is determined according to the center-to-center distance L of the mounting holes 2a of the main body 2 in the flat state described above. It is preferable that the outer diameter is approximately the same as the width dimension H of the main body 2 in the flat state shown in Figure 4, and the center-to-center distance L is determined accordingly.

The countersunk screw 4 can be a commercially available countersunk screw. This allows the sensor fixing device to be manufactured at a low cost. The seat of the countersunk screw is shaped like a truncated cone, and by screwing the countersunk screw 4 into the cylindrical body 4 located at the end of the main body 2, the cylindrical body 4 can be gradually pressed against the piping along the outer diameter of the mounting hole 2a.

Next, the procedure for attaching the sensor S to the pipe using the sensor fixture 1 will be described with reference to Figure 3.

First, as shown in Figure 1, the rod-shaped sensor S is positioned inside the bent part of the main body 2, and is brought closer to the pipe P, and the cylindrical body 3 is positioned between both ends of the main body 2 so as to achieve the positional relationship shown in Figure 3(a). In this state, the pipe P is only lightly clamped by the main body 2, and no force is being applied to the sensor S.

Next, as shown in Figure 3(b), the flat head screw 4 is passed through the mounting hole 2a, and the threaded portion 4a is screwed into the screw hole 3a of the cylindrical body 3. In this state, the seat surface 4b of the flat head screw 4 only comes into contact with a part of the opening edge of the mounting hole 2a at a point on the right side of the figure, and the cylindrical body 3 and the flat head screw 4 are in a state in which they can move left and right in the figure, and no force is applied to the sensor S, as in Figure 3(a).

As shown in FIG. 3(c), by tightening the flat head screw 4, the conical seat 4b of the flat head screw 4 moves along the opening edge of the mounting hole 2a, moving the cylindrical body 3 to the left in the illustration and pressing the pipe P towards the bent portion of the main body 2. As a result, the sensor S, which is arranged between the bent portion of the main body 2 and the pipe P, is clamped and fixed between the bent portion of the main body 2 and the pipe P.

In this case, because a cutout recess 2b is provided at the bent portion of the main body 2, the contact distance of the two line contact points T1 between the pipe P and the main body 2 can be shortened. In addition, the contact point T2 between the pipe P and the cylindrical body 3 becomes a point contact. In this way, there are few contact points between the sensor fixture 1 and the pipe P, which minimizes heat conduction from the sensor fixture and reduces the disruption of the accuracy of the sensor S that measures temperature due to external disturbances.

<Modification>
A modified example of the sensor fixture of the present invention is shown in Fig. 5. This sensor fixture is the same as that of the first embodiment except that the shape of the mounting hole 2a of the main body 2 is different, and therefore a description thereof will be omitted.

The mounting hole 2a opened in the main body 2 of this sensor fixture is the same as that in the first embodiment, and two mounting holes 2a1, 2a2, one above the other, have different center-to-center distances L when in flat plate state. In the example, the center-to-center distance of the upper mounting hole 2a1 in the flat plate state is slightly shorter than L, and the center-to-center distance of the lower mounting hole 2a2 in the flat plate state is slightly longer than L.

This makes it possible to handle cases where the sensor diameter has changed slightly from the design when installing the sensor on-site, where the pipe dimensions differ by a few millimeters, or where the sensor cannot be fixed with sufficient gripping force due to deformation, etc.

In addition, the mounting hole 2a of the main body 2 is the same as in embodiment 1, and the cylindrical body 3 is an elliptical cylinder, so that slight differences in the sensor diameter and piping diameter can be accommodated by rotating the elliptical cylinder.

<Embodiment 2>
The second embodiment relates to a fluid control device in which the above-mentioned sensor fixture is attached to a fluid control device and a temperature sensor for measuring the temperature of a flow path block, for example, is fixed.

Figure 6 shows a fluid control device 10 of the present invention. This fluid control device 10 is configured by arranging various fluid control devices in multiple rows, and connecting the flow paths of the fluid control devices in adjacent rows at predetermined locations by device connection means. In recent years, this type of fluid control device has been integrated to connect mass flow controllers, on-off valves, etc. without using tubes.

The fluid control device 10 shown in FIG. 6 includes multiple fluid control devices 7A-7G on the upper level, multiple flow path blocks 5 with fluid flow paths inside on which the multiple fluid control devices 7A-7G are placed on the lower level, a support member 6 supporting the multiple flow path blocks 5, and a temperature sensor S that is attached to a small sensor attachment hole 5A provided in the flow path block 5 and measures the temperature. Although not shown in the figure, this type of integrated type fluid control device may require a heating device to prevent condensation and to prevent re-liquefaction when a fluid that is liquid at room temperature is gasified and flowed. In such a fluid control device with a heating device, ribbon-shaped planar heaters are arranged on both sides of at least one line, and the temperature of the flow path must be measured.

The flow path block 5 and the fluid control devices 7A-7G are considered as one line, and two lines are shown in the example, but the number of lines is not limited to this, and the number of lines can be freely determined depending on the equipment, from one line to multiple lines.

In this fluid control device 10, the wiring Sa extending from the sensor S is fixed to the cylindrical actuator 70 of the on-off valve 7A, which is a fluid control device, using the sensor fixing device 1 described above.

By using this sensor fixing device, it is possible to effectively prevent the temperature sensor S attached to the fluid control device 10 from accidentally falling out, which can cause the entire device to stop due to poor temperature measurement.

As explained above, the sensor fixture of the present invention can be used effectively not only for new piping that requires temperature measurement but also for existing piping, and can also be used effectively for fixing wiring that may extend from a sensor of a fluid control device equipped with a cylindrical device such as an actuator.

REFERENCE SIGNS LIST 1 sensor fixture 10 fluid control device 2 main body 2a mounting hole 2b missing portion 3 cylindrical body 3a screw hole 4 countersunk screw 4a threaded portion 4b seat surface 5 flow path block 6 support member 7 fluid control device 70 actuator

Claims (3)

A sensor fixture for mounting a sensor on a cylindrical object, comprising:
a main body formed by bending a flat plate-like member into a U-shape so that the inner surface distance between both ends is substantially the same as the diameter of the object;
A cylindrical body having a length substantially equal to the diameter of the object and having screw holes formed on both end surfaces;
The screw is a countersunk screw having a seat surface formed in a truncated cone shape that is screwed into the screw hole,
The sensor fixing device has mounting holes at both ends of the main body, through which the flat head screws that screw into the threaded holes of the cylindrical body are inserted. The sensor fixing device according to claim 1, in which the U-shaped bent portion of the flat plate has a missing portion formed around the entire circumference of the bent portion. A fluid control device;
a flow path block in which a flow path is formed inside the flow control device;
A fluid control device comprising: a fluid control device including a cylindrical actuator, the fluid control device including a sensor fixture according to claim 1 or 2 arranged on the actuator; a sensor unit attached to a sensor mounting hole formed in a flow path block; and a sensor wiring extending from the sensor fixed to a surface of the actuator by the sensor fixture.

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