JP6154623B2 - Pressure gauge - Google Patents

Description

  The present invention relates to a pressure gauge in which a base end of a Bourdon tube is connected to a fluid introduction member.

The base end of the Bourdon tube is connected to the fluid introduction member, and a pointer is provided at the tip of this Bourdon tube via a pointer transmission interlocking mechanism. The tip of the Bourdon tube is displaced by the pressure of the fluid to be measured introduced from the fluid introduction member. A Bourdon tube type pressure gauge that displays this displacement with a pointer is known.
This Bourdon tube type pressure gauge reads the pressure value by displaying the pointer, so it is excellent in visibility. However, in terms of reading accuracy, the Bourdon tube pressure gauge calculates the measured value based on the electrical signal detected by the detector. It does not extend to the measuring device. Therefore, there is a measuring device that combines a Bourdon tube pressure gauge and an electrical measuring device.

  As a conventional example of this type of measuring apparatus, a fluid having a base block whose base end is connected to a Bourdon tube and into which a fluid to be measured flows, and a pressure sensor that is provided on the base block and measures the pressure of the fluid to be measured A physical quantity measuring device (Patent Document 1), a branch pipe provided at the base of a Bourdon tube and communicating with a flow path of the Bourdon pipe, a diaphragm for closing the flow path of the branch pipe, and a sensor having a strain gauge provided on the diaphragm (Patent Document 2), and a gauge (Patent Document 3) in which a variable magnetoresistive phase shift type rotation detector and a digital visual display are added to a Bourdon tube type pressure gauge.

Japanese Patent Laid-Open No. 10-288560 Microfilm of Japanese Utility Model Application No. 55-168627 (Japanese Utility Model Publication No. 57-89941) Microfilm of Japanese Utility Model No. 56-121593 (Japanese Utility Model Publication No. 58-27714)

In the conventional examples shown in Patent Document 1 and Patent Document 2, since the sensor protrudes from the base of the Bourdon tube, the measuring instrument must be enlarged.
In the conventional example shown in Patent Document 3, the variable magnetoresistive phase shift type rotation detector outputs a signal along with the rotation of the rotating shaft rotated by the Bourdon tube, so that the Bourdon tube is driven. If there is an error, the error is output as it is as an electrical measuring device.

  The objective of this invention is providing the pressure gauge which can detect the output of the electrical signal from a detection part correctly while being miniaturized.

The pressure gauge of the present invention includes a fluid introduction member in which a fluid introduction hole into which a fluid to be measured is introduced, a Bourdon tube having a base end connected to the fluid introduction member via a mounting portion, A sensor having a pointer that rotates in accordance with the displacement of the tip and a detection unit that detects the pressure of the fluid to be measured that is incorporated in the attachment unit and is introduced into the fluid introduction member, and that outputs a detection signal from the detection unit An element, and the mounting portion includes a first communication passage communicating with the fluid introduction hole, a second communication passage communicating the first communication passage and the Bourdon tube, and the first communication passages . A sensor mounting hole that is arranged between the second communication path and communicates with the first series path and the second communication path, and inserts the sensor element into the sensor mounting hole; A retaining member for retaining the sensor element; And characterized by providing the hole for urging.

In the present invention having this configuration, the fluid to be measured introduced from the fluid introduction hole of the fluid introduction member is sent from the first series passage of the attachment portion to the Bourdon tube through the second communication passage. The Bourdon tube into which the fluid to be measured is introduced has its tip displaced. The pointer moves with the displacement of the Bourdon tube tip, and the measured value can be read by displaying the pointer. On the other hand, the fluid to be measured introduced from the fluid introduction hole is sent from the first series passage of the attachment part to the sensor element through the sensor attachment hole part. In the sensor element, the detection unit detects the pressure of the fluid to be measured, and the detected electrical signal is output. Thereby, it becomes possible to calculate and display the measured value based on the electric signal.
In the present invention, the sensor mounting hole provided with the sensor element and the Bourdon tube introduce the fluid to be measured from the first series passage, respectively, so that the same pressure is applied to the sensor element and the Bourdon tube. Therefore, the electrical signal detected by the detection unit of the sensor element is output more accurately than the conventional example that is detected using the displacement of the Bourdon tube.
In addition, since the sensor element is built in the mounting portion, the pressure gauge can be downsized.
Furthermore, since the sensor element is built in the mounting portion, the sensor element does not protrude from the mounting portion, so that the sensor element is not accidentally touched, and the assembling work is facilitated.

The pressure gauge of the present invention includes a fluid introduction member in which a fluid introduction hole into which a fluid to be measured is introduced, a Bourdon tube having a base end connected to the fluid introduction member via a mounting portion, A sensor having a pointer that rotates in accordance with the displacement of the tip and a detection unit that detects the pressure of the fluid to be measured that is incorporated in the attachment unit and is introduced into the fluid introduction member, and that outputs a detection signal from the detection unit An element, a pointer transmission mechanism that transmits movement of the Bourdon tube to the pointer, and a base to which the pointer transmission mechanism is attached. The attachment portion includes a first series passage that communicates with the fluid introduction hole, A second communication path communicating with the series passage and the Bourdon tube, and a sensor mounting hole communicating with the first series path and the second communication path are formed, and the sensor mounting hole is provided with the sensor. While inserting the element, The stop member for the retaining elements are provided in the sensor attachment hole, the attachment portion is a block body which is mounted to the base, the first communication passage and said fluid introducing member of the block body The fluid introduction hole communicates with each other through a communication pipe .
In this configuration, the pressure gauge can be arranged at a position that does not interfere with the pointer transmission mechanism arranged inside the pressure gauge by providing the mounting section through the base while providing the above-described effects. Can be made compact.

In the present invention, the sensor element has a cylindrical portion and a diaphragm provided in the cylindrical portion, a fluid to be measured is introduced into the cylindrical portion, and the detection portion is provided in the diaphragm. A configuration having a strain gauge provided is preferable.
In this configuration, when the fluid to be measured displaces the diaphragm, an electric signal is output from the strain gauge.
Therefore, the sensor element has a structure in which a diaphragm is provided in the cylindrical part and a strain gauge is provided in the diaphragm, so that it is suitable not only for detecting the pressure of a high-pressure fluid to be measured but also to the attachment part. Installation can be performed easily.

The front view which shows the internal structure of the pressure gauge concerning one Embodiment of this invention. The side view which notched a part of said pressure gauge. The front view which shows the state in which the attaching part was attached to the base. The exploded sectional view of an attaching part. The front view which fractured | ruptured a part of attachment structure to the attachment part of a Bourdon tube. The side view which fractured | ruptured a part of attachment structure to the attachment part of a Bourdon tube.

An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows an internal structure of the pressure gauge according to the present embodiment, and FIG. 2 shows a side surface in which a part of the pressure gauge is cut out.
1 and 2, the pressure gauge includes a joint 1 as a pressure introducing member attached to a member to be attached such as a pipe (not shown), a bottomed cylindrical case 2 fixed to the joint 1, and the case 2 A base 3 provided on the base 3, a mounting portion 4 provided on the base 3, a Bourdon tube 5 provided with a base end on the mounting portion 4, a pointer 6 connected to a distal end side of the Bourdon tube 5, and a Bourdon tube 5 Provided with a pointer transmission mechanism 7 that transmits the movement of the pointer 6 to the pointer 6, a sensor element 8 built in the mounting portion 4, a scale plate 9 that is attached to the front surface of the case 2, and a cover 10 that covers the scale plate 9. Structure.

The joint 1 includes a main body portion 11 and a screw portion 12 provided at the distal end portion of the main body portion 11 and has a structure formed integrally with a metal member such as brass, stainless steel, or steel. The screw portion 12 is screwed to the attached member.
A fluid introduction hole 1 </ b> A for introducing a fluid to be measured is formed inside the joint 1.

The case 2 includes a disc portion 21 and a cylindrical portion 22 provided on the outer peripheral edge of the disc portion 21 and is made of a metal material such as iron or stainless steel or other materials. A proximal end portion of the main body portion 11 of the joint 1 is attached to the peripheral surface of the cylindrical portion 22.
A scale plate 9 is housed inside the case 2, and between the scale plate 9 and the disc portion 21 of the case 2, the base 3, the mounting portion 4, the Bourdon tube 5, the pointer transmission mechanism 7, and the sensor element 8 is arranged.
The base 3 includes a plate portion 31 disposed in parallel with the disc portion 21 and two support columns 32 for supporting the back surface of the plate portion 31 on the disc portion 21. A hole (not shown) is formed at a position where the plate portion 31 abuts on the column portion 32, and one end portion of a columnar support member (not shown) is inserted through this hole and connected to the column portion 32. The end portion supports the back surface of the scale plate 9. The scale plate 9 is attached to the support member by screws indicated by reference numeral 90 in FIG.
Inside the Bourdon tube 5, a circulation port 5 </ b> A is formed through which the fluid to be measured flows.
The pointer 6 includes a pointer main body 61 and a shaft portion 62 that is fixed to the base end portion of the pointer main body 61 and passes through the center portion of the scale plate 9 and is connected to the pointer transmission mechanism 7.

The pointer transmission mechanism 7 increases the amount of displacement of the distal end portion of the Bourdon tube 5 and transmits it to the pointer 6, and is connected to the connection member 71 connected to the distal end portion of the Bourdon tube 5 and the connection member 71. And an internal unit 72 that transmits the displacement of the tip of the Bourdon tube 5 to the pointer 6.
The inner unit 72 includes a lower plate 74 and an upper plate 75 that are arranged to face each other via a support portion 73 and rotatably support the shaft portion 62 of the pointer 6, and a pinion (not shown) provided on the shaft portion 62. A sector 76 having one end meshed with the pinion and rotatably supported on the lower plate 74 and the upper plate 75, and one end engaged with the other end of the sector 76 and the other end connected to the connecting member 71. And a rod 77 supported rotatably. The lower plate 74 is attached to the base 3.

On the front surface of the scale plate 9, necessary scales and numbers for displaying the pressure value together with the pointer 6 are described.
The cover 10 includes a cover main body 101 that fits into the cylindrical portion 22 of the case 2 and a disk-like window member 102 provided on the cover main body 101, and the window member 102 is spaced from the scale plate 9 by a predetermined interval. They are spaced apart from each other.
An annular packing (not shown) is interposed between the window member 102 and the opening end surface of the case 2.
The attachment portion 4 and the joint 1 are connected via a communication pipe 13.
The communication pipe 13 is connected to the pipe main body 13A, a connection portion 13B provided at one end of the pipe main body 13A and connected to the joint 1 on the proximal end side, and provided at the other end of the pipe main body 13A. 13C.

The detailed structure of the attachment portion 4 is shown in FIGS.
FIG. 3 shows a state where the attachment portion 4 is attached to the base 3, and FIG. 4 shows a cross section of the attachment portion 4.
3 and 4, the attachment portion 4 is a prismatic block body having one side surface fixed to the plate portion 31, and is connected to one of two side surfaces orthogonal to the side surface to which the plate portion 31 is fixed. 13C is provided, and the base end portion of the Bourdon tube 5 is provided on the other side. The attachment position of the plate part 31 of the attachment part 4 is a position that does not interfere with the pointer transmission mechanism 7 (see FIG. 1).

Inside the mounting portion 4, a first series passage 41 that communicates with the fluid introduction hole 1 </ b> A of the joint 1 through the communication pipe 13, and a second communication path 42 that communicates the first series passage 41 and the Bourdon pipe 5. And a sensor mounting hole 43 communicating with the first series passage 41 and the second communication passage 42 are formed.
Each of the first series passage 41 and the second communication passage 42 is formed of a hole having a straight axis, and these axes are aligned. In the present embodiment, the axial centers of the first series passage 41 and the second communication passage 42 are not necessarily limited to being in a straight line, and may be offset. In FIG. 4, the first series passage 41 has a larger diameter than the second communication path 42. The relationship between the diameters of the first series passage 41 and the second communication path 42 is illustrated in FIG. 4. However, the diameter of the first series passage 41 may be smaller than that of the second communication passage 42, and both may have the same diameter.

The sensor mounting hole 43 has a distal end portion 43A provided between the first series passage 41 and the second communication passage 42, and is provided continuously to the distal end portion 43A. An insertion hole portion 43B communicating with the female screw portion 43C and a female screw portion 43C formed continuously to the insertion hole portion 43B are provided, and the axial centers of the first series passage 41 and the second communication passage 42 are provided. Orthogonal to the axis.
The insertion hole 43 </ b> B has an inner peripheral surface that matches the outer peripheral shape of the sensor element 8. In the state where the sensor element 8 is inserted into the insertion hole 43B, the retaining member 40 is provided in the female screw portion 43C. In the state where the retaining member 40 is provided in the female screw portion 43C, the surface exposed to the outside of the retaining member 40 is the same surface as the surface on which the female screw portion 43C of the mounting portion 4 is formed.
The retaining member 40 is an annular member in which a male screw portion 440 that is screwed to the female screw portion 43C is formed on the outer peripheral portion.

The sensor element 8 is a metal member in which a stepped cylindrical portion 81 whose outer peripheral surface faces the sensor mounting hole 43 and a diaphragm 82 provided on one end side of the cylindrical portion 81 are integrally formed. And the fluid to be measured is introduced into the cylindrical portion 81.
The sensor element 8 is sandwiched between the retaining member 40 and the bottom surface of the sensor mounting hole 43.
A detection portion 80 made of a strain gauge is formed in a portion of the diaphragm 82 exposed from the internal space of the retaining member 40. One end of a linear conductive member 83A is connected to the detection unit 80.

Returning to FIGS. 1 and 2, the other end portion of the linear conductive member 83 </ b> A is connected to a sensor circuit portion 84 provided on the scale plate 9.
The sensor circuit portion 84 has a structure in which an electronic component 84B is provided on a disc-shaped mounting board 84A, and a cover body 86 that covers the front surface of the mounting board 84A is provided on the scale plate 9. By turning a variable resistor adjusting screw (not shown) at a predetermined position of the sensor circuit portion 84 that can be seen from the operation hole 86A formed in the cover body 86, the offset and the linear gain can be adjusted.
One end of a linear conductive member 83B is connected to the electronic component 84B, and a terminal member 85 attached to the disc portion 21 of the case 2 is connected to the other end of the linear conductive member 83B. The electrical signal detected by the detection unit 80 from the terminal member 85 is amplified by the sensor circuit unit 84 and output to the outside. The electric signal output to the outside is taken in by a control device (not shown), the measured value is calculated, and the result can be displayed on a display unit (not shown).

The attachment structure of the Bourdon tube to the attachment portion is shown in FIGS.
FIG. 5 shows a front view of a part of the attachment structure of the Bourdon tube 5 to the attachment part 4. FIG. 6 shows a side view of a part of the attachment structure of the Bourdon tube 5 to the attachment part 4. It is shown.
5 and 6, the mounting portion 4 has two wall portions 45 facing each other on the side surface on which the Bourdon tube 5 is provided along the axial direction, and the Bourdon tube 5 is interposed between these wall portions 45. The base end of is fitted. The end of the second communication passage 42 is opened in the Bourdon tube 5. The wall 45 and the base end of the Bourdon tube 5 are joined to each other by welding.

In the pressure gauge having the above configuration, the joint 1 is attached in advance to a member to be attached such as a pipe. The fluid to be measured that flows through the inside of the attached member is introduced into the fluid introduction hole 1A of the joint 1, and further, the sensor is attached to the second communication passage 42 through the communication pipe 13 and the first series passage 41 of the attachment portion 4. To the hole 43 for use.
The fluid to be measured passing through the second communication path 42 is sent to the Bourdon tube 5, and the tip of the Bourdon tube 5 into which the fluid to be measured is introduced is displaced. When the tip of the Bourdon tube 5 is displaced, the displacement is expanded by the pointer transmission mechanism 7 and transmitted to the pointer 6, and the pointer 6 is rotated. The scale plate 9 reads the position where the rotated pointer 6 stops.
On the other hand, the fluid to be measured sent from the first series passage 41 of the mounting portion 4 to the sensor mounting hole 43 displaces the diaphragm 82 of the sensor element 8. When the diaphragm 82 is displaced, an electrical signal detected from the detection unit 80 is output to the control device disposed outside through the sensor circuit unit 84 and the terminal member 85. In the control device, the measured value is calculated and the result is displayed.

Therefore, in this embodiment, the following effects can be achieved.
(1) A joint 1 in which a fluid introduction hole 1A is formed, a Bourdon tube 5 having a proximal end connected to the joint 1 via a mounting portion 4, and a rotation of the Bourdon tube 5 according to the displacement of the distal end. A needle 6 and a sensor element 8 having a detection unit 80 that detects the pressure of a fluid to be measured that is built in the attachment portion 4 and introduced into the fluid introduction hole 1A of the joint 1 are provided. A first series passage 41 communicating with 1A, a second communication path 42 communicating with the first series path 41 and the Bourdon tube 5, and a sensor mounting hole communicating with the first series passage 41 and the second communication path 42. The sensor element 8 is inserted into the sensor mounting hole 43, and a retaining member 40 that prevents the sensor element 8 from being detached is provided in the sensor mounting hole 43. For this reason, the sensor mounting hole 43 and the Bourdon tube 5 introduce the fluid to be measured from the first series passage 41, and the same pressure is applied to the sensor element 8 and the Bourdon tube 5. Compared to the conventional example in which an electrical signal is output in accordance with the displacement, the pressure directly generated in the sensor element 8 is detected and output by the detection unit 80, so that the measurement accuracy can be increased. In addition, since the sensor element 8 is built in the attachment portion 4, the pressure gauge can be downsized as compared with the case where the sensor element 8 is provided protruding from the attachment portion 4. In particular, since the Bourdon tube 5 and the mounting portion 4 in which the sensor element 8 is housed are housed in the case 2, the pressure gauge can be downsized according to the size of the case 2. Further, since the sensor element 8 is built in the mounting portion 4, the sensor element 8 does not protrude from the mounting portion 4, and therefore the detection portion 80 of the sensor element 8 may be erroneously touched when the pressure gauge is assembled. Since there is no assembly work, it becomes easy.

(2) The pressure gauge includes a pointer transmission mechanism 7 that transmits the movement of the distal end portion of the Bourdon tube 5 to the pointer 6 and a base 3 to which the pointer transmission mechanism 7 is attached. The mounting portion 4 is attached to the base 3. Since the first series passage 41 and the fluid introduction hole 1A of the block body are communicated with each other through the communication pipe 13, the mounting portion 4 is disposed at a position where it does not interfere with the pointer transmission mechanism 7. The thickness dimension of the case 2 can be reduced and the pressure gauge can be made compact.

(3) Since the retaining member 40 is an annular member formed on the outer periphery with a male threaded portion 440 that is screwed into the female threaded portion 43C of the sensor mounting hole 43, the retaining member 40 can be reliably prevented from coming off from the mounting portion 4. The attachment work of the retaining member 40 to the attachment portion 4 can be easily performed. Further, since the retaining member 40 is an annular member, the central portion thereof is a space for drawing out the linear conductive member 83A for taking out the detection signal from the detection unit 80 of the sensor element 8, so that the assembly work of the pressure gauge Can be easily performed.

(4) Since the base end portion of the Bourdon tube 5 is fitted between the two wall portions 45 of the attachment portion 4, the wall portion 45 can be positioned when attaching the Bourdon tube 5 to the attachment portion 4. The attachment work of the Bourdon tube 5 to the attachment portion 4 can be easily performed.

(5) The sensor element 8 is a bottomed cylindrical member made of metal having a cylindrical portion 81 and a diaphragm 82 provided on the cylindrical portion 81 and having a strain gauge as the detecting portion 80 formed therein. Not only is it suitable for detecting the pressure of a high-pressure fluid to be measured, but it can be easily attached to the attachment portion 4.

In addition, this invention is not limited to the said embodiment, Including other structures etc. which can achieve the objective of this invention, the deformation | transformation etc. which are shown below are also contained in this invention.
For example, in the above-described embodiment, in order to attach the retaining member 40 to the sensor mounting hole 43, the sensor mounting hole 43 includes the female thread portion 43C, and the retaining member 40 includes the male thread portion 440. However, in the present invention, a cylindrical portion may be used instead of the female screw portion 43C, a cylindrical portion may be used instead of the male screw portion 440, and these may be fixed by welding.
Further, the end surface of the retaining member 40 may be configured to recede from the end surface on which the male screw portion 43C of the mounting portion 4 is formed.

Moreover, in the said embodiment, the structure which abbreviate | omits the communication pipe 13 and attaches the attaching part 4 to the coupling 1 directly may be sufficient. Further, the cross-sectional shape of the Bourdon tube 5 may be circular or elliptical.
Further, in the present invention, the internal unit 72 that transmits the displacement of the distal end portion of the Bourdon tube 5 to the pointer 6 may be omitted, and the displacement of the distal end portion of the Bourdon tube 5 may be directly transmitted to the pointer 6.
Further, the sensor element 8 is configured such that the tubular portion 81 and the diaphragm 82 are integrally formed, and the fluid to be measured is introduced into the tubular portion 81, and the detection portion 80 made of a strain gauge is formed in the diaphragm 82. However, the present invention is not limited to this configuration. For example, the sensor element may be a capacitive sensor element.

  DESCRIPTION OF SYMBOLS 1 ... Joint (pressure introduction member), 1A ... Fluid introduction hole, 3 ... Base, 4 ... Mounting part, 5 ... Bourdon tube, 6 ... Pointer, 7 ... Pointer transmission mechanism, 8 ... Sensor element, 9 ... Scale plate, 13 ... Communication pipe, 40 ... Retaining member, 41 ... First series passage, 42 ... Second communication passage, 43 ... Sensor mounting hole, 43B ... Insertion hole, 43C ... Female thread, 45 ... Wall, 80 ... Detection Part

Claims (3)

A fluid introduction member in which a fluid introduction hole into which a fluid to be measured is introduced is formed; a Bourdon tube having a base end connected to the fluid introduction member via a mounting portion; A moving pointer, and a sensor element that has a detection unit that detects the pressure of a fluid to be measured that is built in the attachment unit and is introduced into the fluid introduction member, and that outputs a detection signal from the detection unit,
The mounting portion includes a first series passage communicating with the fluid introduction hole, a second communication path communicating the first series passage and the Bourdon tube, and the first series passage and the second communication path . And a sensor mounting hole that communicates with the first series passage and the second communication passage .
A pressure gauge, wherein the sensor element is inserted into the sensor mounting hole, and a retaining member for preventing the sensor element from being detached is provided in the sensor mounting hole. A fluid introduction member in which a fluid introduction hole into which a fluid to be measured is introduced is formed; a Bourdon tube having a base end connected to the fluid introduction member via a mounting portion; A pointer that moves , a sensor element that detects the pressure of the fluid to be measured that is built in the mounting part and is introduced into the fluid introduction member, and that outputs a detection signal from the sensor part; and It has a pointer transmission mechanism that transmits movement to the pointer, and a base to which this pointer transmission mechanism is attached.
The mounting portion includes a first series passage communicating with the fluid introduction hole, a second communication path communicating the first series passage and the Bourdon tube, and the first series passage and the second communication path. A communicating sensor mounting hole is formed,
The sensor element is inserted into the sensor mounting hole, and a retaining member for preventing the sensor element from being removed is provided in the sensor mounting hole.
The attachment portion is a block body attached to the base, and the first series passage of the block body and the fluid introduction hole of the fluid introduction member communicate with each other through a communication pipe. . In the pressure gauge according to claim 1 or 2,
The sensor element includes a cylindrical part and a diaphragm provided in the cylindrical part, a fluid to be measured is introduced into the cylindrical part, and the detection part is a strain gauge provided in the diaphragm. A pressure gauge characterized by comprising:

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