CN113203490A

CN113203490A - Temperature indicating meter

Info

Publication number: CN113203490A
Application number: CN202010837193.1A
Authority: CN
Inventors: 大内优; 月冈周郎
Original assignee: Nike Co ltd
Current assignee: Nestec SA; Nike Co ltd
Priority date: 2020-01-16
Filing date: 2020-08-19
Publication date: 2021-08-03
Also published as: KR20210092653A; JP2021113698A; JP6694121B1

Abstract

The present invention relates to a temperature indicator. In order to achieve the miniaturization of a temperature sensing cylinder and the overall size and to accurately measure a temperature even when a temperature measuring region is narrow and a measuring part is at a high temperature, a temperature indicator includes: a temperature sensing cylinder in which a working fluid that expands and contracts in accordance with the temperature of a measurement target portion is sealed; a main body case forming a closed space; a bourdon tube elastically displaced in accordance with a pressure change caused by expansion and contraction of a working fluid; a capillary tube connecting the temperature sensing cylinder and the bourdon tube; and a temperature indicating section having a pointer and a scale plate. The pointer is rotatable about the axis of rotation in response to the resilient displacement of the bourdon tube. The bourdon tube is formed in a spiral shape at predetermined turns and can be elastically displaced in the radial direction. The other end portion of the bourdon tube is movable about the rotation axis in accordance with the elastic displacement of the bourdon tube. The working fluid is sealed in the capillary and the Bourdon tube.

Description

Temperature indicating meter

Technical Field

The present invention relates to a temperature indicator.

The present application claims priority from application Ser. No. 2020-.

Background

Conventionally, there are various types of temperature indicators for measuring the temperature of a measurement target portion depending on the application, installation location, and the like, and for example, as shown in patent documents 1 and 2 below, a temperature indicator using a glass rod thermometer as a temperature measuring portion is widely known.

In such a temperature indicator, alcohol or the like is often used as the temperature measuring liquid, but for example, in the case of measuring a temperature measuring region having a high temperature of 150 ℃ or higher, mercury is more preferably used as the temperature measuring liquid. However, in recent years, measures for prohibiting the use of mercury have been taken from the viewpoint of environmental protection.

Therefore, the bourdon tube is known as a temperature indicator that can measure a temperature measurement area at the same level as that when mercury is used, without using mercury.

For example, a hydraulic temperature indicator is known, which includes: a temperature sensing part with working liquid sealed inside; an arc-shaped bourdon tube that elastically displaces based on a pressure change caused by expansion and contraction of the working fluid; and an amplification transmission mechanism for amplifying the elastic displacement of the Bourdon tube and transmitting the amplified displacement to the pointer.

According to the temperature indicator, the bourdon tube can be elastically displaced based on a pressure change caused by expansion and contraction of the working fluid, and the elastic displacement amount of the bourdon tube can be transmitted to the indicating needle in an enlarged state by the enlargement transmission mechanism, and the indicating needle can be rotated. Therefore, a temperature measurement region of high temperature can be measured without using mercury.

Documents of the prior art

Patent document

Patent document 1: japanese Utility model registration No. 3130262

Patent document 2: japanese Kokai publication Sho-49-106378

Disclosure of Invention

Problems to be solved by the invention

The temperature indicator using the bourdon tube is a system for measuring a temperature by using a pressure change (volume change) due to expansion and contraction of a working fluid containing a working liquid, and therefore, it is necessary to keep the displacement linearity of the bourdon tube with respect to the pressure change at a high temperature. Therefore, it is required to increase the internal volume of the temperature sensing cylinder in which the working fluid is sealed. By increasing the internal volume, the displacement linearity (linearity) of the bourdon tube can be improved, and the temperature measurement accuracy can be improved.

Specifically, in many cases, a large internal volume is ensured by forming a temperature sensing cylinder, which is formed in a cylindrical shape with a predetermined outer diameter and in which a working fluid can be sealed, to be long in the axial direction. Therefore, in the conventional temperature indicator using the bourdon tube, the temperature sensing tube is generally formed long.

Such a temperature indicator using a bourdon tube is widely used in various applications, for example, in a cooling and heating air-conditioning duct, a cooling and heating water duct, various boilers, industrial equipment, a marine engine, and the like. Specifically, in these respective installation places, the temperature indicator may be attached to a container containing various fluids such as gas and liquid, or a pipe through which the fluids flow.

In order to accurately measure the temperature of the fluid, it is necessary to insert the temperature sensing cylinder from the outside through an attachment port provided in the container, the pipe, or the like, and attach the temperature indicator in a state where the temperature sensing cylinder is appropriately provided in the container or the pipe.

However, in a marine engine or the like, for example, the diameter of a pipe through which exhaust gas (a measurement target portion) flows is often small, and accordingly, the insertion length for inserting the temperature sensing cylinder into the pipe is often set short. Therefore, in the conventional temperature indicator, since the length of the temperature sensing cylinder is long, a part of the temperature sensing cylinder is exposed to the outside of the pipe line, and the temperature of the exhaust gas cannot be measured accurately, which may cause a problem such as poor indication.

In particular, in the case of a marine engine, since exhaust gas is high in temperature, it is necessary to provide the entire temperature sensing cylinder in a narrow temperature measurement region in a pipeline, but it is difficult for a conventional temperature indicator in which the length of the temperature sensing cylinder is long to satisfy such a demand.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a temperature indicator capable of accurately measuring a temperature even when a temperature measuring region is narrow and a measuring portion is at a high temperature, while achieving downsizing of a temperature sensing cylinder and the entire size.

Means for solving the problems

(1) The temperature indicator of the present invention comprises: a temperature sensing cylinder in which a working fluid is sealed, the working fluid expanding and contracting in accordance with a temperature of a portion to be measured; a main body housing, in which a closed space is formed; a connection pipe provided between the temperature sensing cylinder and the main body case and integrally connecting the temperature sensing cylinder and the main body case; a bourdon tube disposed in the main body housing and elastically displaced according to a pressure change caused by expansion and contraction of the working fluid; a capillary tube that connects the temperature sensing cylinder and the bourdon tube in a state where the inside of the temperature sensing cylinder and the inside of the bourdon tube are communicated; a temperature indicating part provided in the main body case and having a pointer indicating a temperature corresponding to the elastic displacement of the Bourdon tube and a scale plate. The capillary tube is provided from the inside of the connection tube to the inside of the closed space, is connected to the temperature sensing cylinder inside the connection tube, and is connected to one end of the bourdon tube inside the closed space. The pointer is connected to the other end portion of the bourdon tube and is rotatable about a rotation axis in accordance with elastic displacement of the bourdon tube. The bourdon tube is formed in a spiral shape with a predetermined number of turns around the rotation axis as a center, and is elastically displaceable in a radial direction, when viewed from the direction of the rotation axis. The other end portion of the bourdon tube may move around the rotation axis in accordance with the elastic displacement of the bourdon tube. The working fluid is sealed inside the capillary and inside the Bourdon tube.

According to the temperature indicator of the present invention, since the working fluid sealed in the temperature sensing cylinder expands and contracts in accordance with the temperature of the measurement target portion, the working fluid in the capillary tube and the working fluid in the bourdon tube also expand and contract in accordance with the expansion and contraction. Accordingly, the bourdon tube formed in a spiral shape is elastically displaced in the radial direction in accordance with a pressure change caused by expansion and contraction of the working fluid. Thus, the other end portion of the bourdon tube can be moved circumferentially (rotationally) around the rotation axis in accordance with the elastic displacement of the bourdon tube. Therefore, the pointer can be rotated about the rotation axis in accordance with the elastic displacement of the bourdon tube, and the temperature indication (temperature display) of the portion to be measured can be performed by the scale plate and the pointer.

In particular, since the temperature sensing cylinder and the bourdon tube are connected by the capillary tube, the bourdon tube does not need to extend to the temperature sensing cylinder and can be left inside the main body case. Therefore, the entire length of the bourdon tube can be made shorter than in the case of the system in which the bourdon tube is directly connected to the temperature sensing tube. Therefore, the bourdon tube can be formed into a spiral shape with a small number of turns, the outer diameter of the bourdon tube as a whole can be suppressed, and the bourdon tube itself can be miniaturized.

In this way, the entire length is shortened to form a spiral shape with a small number of turns, and the bourdon tube is miniaturized, so that even when the thermal expansion coefficient of the working fluid is small, that is, the working fluid slightly expands and contracts, the bourdon tube can be elastically displaced with a good reaction. Therefore, the internal volume of the temperature sensing cylinder for sealing the working fluid can be reduced, and the length of the temperature sensing cylinder can be made shorter than that of the conventional one. Therefore, the temperature sensing cylinder can be miniaturized.

Further, since the length of the temperature sensing cylinder can be shortened to achieve miniaturization, even in a narrow temperature measurement region, it is easy to appropriately install the temperature sensing cylinder in the temperature measurement region. Further, since the temperature is measured based on the expansion and contraction of the working fluid without using mercury or the like, the temperature can be accurately measured even if the measured portion is at a high temperature. For these reasons, even when the temperature measurement region is narrow and the measured portion is at a high temperature, the temperature measurement can be performed accurately.

Further, since the temperature sensing cylinder and the one end portion of the bourdon tube are connected by the capillary tube, not only the total length, curvature, number of turns, and the like of the bourdon tube can be easily set according to design, but also the movement of the bourdon tube can be concentrated on the elastic displacement in the radial direction, and therefore the amount of the elastic displacement can be accurately controlled. Therefore, the accuracy of the measurement result can be improved. Further, since a gearless system for rotating the indicating needle by the elastic displacement of the bourdon tube can be adopted without using a gear or the like, a measurement error or the like due to gear engagement does not occur. In this regard, high accuracy of the measurement result can be achieved. In addition, because a gearless mode can be adopted, the durability is easier to improve, and the service life of the product can be prolonged.

Further, since miniaturization can be achieved by suppressing the outer diameter size of the bourdon tube, the internal volume of the closed space can be suppressed, and miniaturization of the main body casing itself can also be achieved. Therefore, miniaturization of the entire temperature indicator can be achieved. Therefore, the temperature indicator can be more easily applied to a location where it is difficult to secure an installation space, and can be applied to, for example, a ship engine or the like. Further, unlike the stick thermometer, since a dial system for indicating the temperature by rotating the pointer around the rotation axis can be adopted, the reading is easier, and the visual recognition can be further improved.

(2) The capillary tube may include: a first capillary tube connected to the temperature sensing cylinder; a second capillary tube connected to the one end portion of the bourdon tube; and a third capillary. The first capillary, the second capillary, and the third capillary may be integrally combined in a state of communicating with each other through a relay member. The third capillary tube may be used as an introduction tube for introducing the working fluid into the inside of the temperature sensing cylinder and the inside of the bourdon tube through the first capillary tube and the second capillary tube.

In this case, since the capillary tube is composed of the first capillary tube, the second capillary tube, and the third capillary tube which are communicated with each other, the capillary tube can be more easily and reliably connected to the temperature sensing cylinder and the bourdon tube, and the working fluid can be more easily sealed.

In particular, after the first capillary tube and the bourdon tube are connected and the second capillary tube and the bourdon tube are connected, the working fluid can be more easily and smoothly sealed by the third capillary tube serving as the introduction tube. That is, by introducing the working fluid into the third capillary, the working fluid can be smoothly introduced into the temperature sensing cylinder and the bourdon tube through the first capillary and the second capillary. Therefore, the working fluid can be sealed in all of the cartridge, the capillary tube, and the bourdon tube. Therefore, even when the bourdon tube is miniaturized, the working fluid can be reliably sealed in the bourdon tube, and the temperature measurement can be stably performed.

(3) The relay member includes: a relay plate fixed to the body case and having a receiving hole formed therein; and a relay sleeve fixed in the accommodation hole in an embedded state. A plurality of insertion holes may be formed in the relay sleeve, the plurality of insertion holes may axially penetrate the relay sleeve, and the first capillary, the second capillary, and the third capillary may be inserted through the plurality of insertion holes, respectively. The first capillary, the second capillary, and the third capillary may be fixed in the insertion hole and communicate with each other in the accommodation hole.

In this case, the first capillary, the second capillary, and the third capillary can be reliably combined in a state of communicating with each other by the relay member.

For example, the first capillary, the second capillary, and the third capillary may be integrally combined with the relay sleeve by inserting the first capillary, the second capillary, and the third capillary into the insertion holes of the relay sleeve, and then fixing the first capillary, the second capillary, and the third capillary by welding or the like. Then, after the relay sleeve is fitted into the receiving hole, it is fixed by welding or the like, and the relay plate and the relay sleeve can be integrally combined. Thus, the first capillary, the second capillary, and the third capillary can be combined to the relay plate fixed to the main body case through the relay sleeve.

Therefore, the first capillary, the second capillary, and the third capillary are not shaken in the main body case, and a stable posture can be maintained. Further, by fitting the relay sleeve into the accommodation hole, the first capillary, the second capillary, and the third capillary can be reliably communicated with each other in the accommodation hole.

(4) The main body shell can be internally provided with: a rotation shaft portion that is combined with the main body case in a state of being provided coaxially with the rotation axis; a first rotating bracket rotatably combined to the rotating shaft portion about the rotation axis and mounted with the pointer; a second rotating bracket rotatably combined to the rotating shaft portion about the rotation axis and connected to the other end portion of the bourdon tube and positioning the bourdon tube in the rotation axis direction; a coupling body that couples the first rotating bracket and the second rotating bracket and rotates the first rotating bracket in accordance with rotation of the second rotating bracket.

At this time, the other end portion moves around the rotation axis due to the elastic displacement of the bourdon tube, and the second rotating bracket can be rotated around the rotation axis along with the other end portion. Thus, the first rotating bracket can be rotated about the rotation axis by the coupling body, and the pointer can be rotated about the rotation axis. Therefore, the pointer can be finally rotated based on the elastic displacement of the bourdon tube without using a gear or the like, and the temperature can be indicated.

In particular, since the respective members of the first rotating bracket, the second rotating bracket, the coupling body, the bourdon tube, and the pointer can be compactly combined by the rotating shaft portion combined with the main body case, it is possible to realize stable operation performance while maintaining accuracy of temperature indication even if the size of the main body case is miniaturized.

(5) The joint may have a bimetal that combines a high expansion portion and a low expansion portion having different thermal expansion rates and deforms in accordance with a temperature change when the temperature in the main body case reaches a predetermined temperature or more. The bimetal may rotate the first rotating bracket in a direction opposite to a rotating direction based on the elastic displacement of the bourdon tube by being deformed.

At this time, when the temperature in the main body case reaches a predetermined temperature or more, the bimetal deforms according to the temperature change, rotating the first rotating bracket, which is about to rotate along with the rotation of the second rotating bracket, in a direction opposite to the elastic displacement direction of the bourdon tube. Thus, even if the bourdon tube is elastically displaced due to the influence of the temperature change in the main body case, the rotation of the first rotating bracket (i.e., the rotation of the pointer) caused by the temperature change in the main body case can be eliminated. Thus, it is possible to correct a temperature error caused by a temperature change in the main body casing, and to cause the pointer to indicate the temperature based only on the temperature change of the measured portion even if the temperature in the main body casing is at, for example, a high temperature. Therefore, the reliability of the measurement result can be further improved.

(6) The scale plate may be arranged such that scales indicating temperature are arranged in a circumferential direction centering on the rotation axis, and intervals of the scales are unequally arranged in a predetermined temperature range unit. The scale may be unevenly provided based on a change in the amount of elastic displacement of the bourdon tube with respect to a temperature change of the measured portion.

In this case, by miniaturizing the bourdon tube, even if the change in the elastic displacement amount of the bourdon tube with respect to the temperature change of the portion to be measured is a nonlinear change, the scale of the scale plate corresponding thereto is a non-uniform scale, and therefore, the temperature can be accurately indicated. Therefore, a more reliable temperature indication can be performed.

(7) The connection pipe may be formed in a straight pipe shape extending in an axial direction of the temperature sensing cylinder.

In this case, the connection pipe may be, for example, a straight stainless steel pipe, and the temperature sensing cylinder and the main body case may be integrally connected more reliably and stably. Further, since the size of the main body case can be reduced as described above, the center of gravity of the entire temperature indicating gauge can be shifted toward the temperature sensing cylinder, and the center of gravity of the temperature indicating gauge can be lowered. Therefore, not only vibration resistance can be improved by miniaturization, but also visual recognition of the temperature indicating portion including the pointer can be improved.

(8) The connection pipe may be connected to the main body case in such a manner as to cross the rotation axis.

At this time, since the scale plate and the pointer may be directed in a direction different from the axial direction of the temperature sensing cylinder and the connection pipe, they may be not expressed upward but expressed forward. Therefore, the visual recognition of the temperature indicating section including the scale plate and the pointer can be further improved.

(9) The connection pipe may include a flexible pipe having flexibility.

In this case, since the flexible tube can be bent arbitrarily, the main body case can be provided, for example, at a position away from the temperature sensing tube. Therefore, the temperature indicator can be used in different usage forms according to the usage, installation place, and the like, and is easy to use and improved in convenience.

Effects of the invention

According to the temperature indicator of the present invention, not only can the temperature sensing cylinder and the entire size be reduced, but also the temperature can be accurately measured even when the temperature measurement area is narrow and the temperature of the measurement target portion is high.

Drawings

Fig. 1 is a view showing an embodiment of the present invention, and is a front view of a temperature indicator.

Fig. 2 is a side view of the temperature indicator shown in fig. 1.

Fig. 3 is a longitudinal sectional view of the temperature indicator shown in fig. 2.

Fig. 4 is a front view of the temperature indicator shown in fig. 1 in a state of being pulled out from the protection tube.

Fig. 5 is a longitudinal sectional view of the temperature sensing part having the lever and the temperature sensing cylinder shown in fig. 3.

Fig. 6 is an enlarged sectional view of the periphery of the main body case shown in fig. 3.

Fig. 7 is a sectional view taken along the line a-a shown in fig. 6.

Fig. 8 is a front view of the housing of the main body housing shown in fig. 6.

Fig. 9 is a top view of the bourdon tube shown in fig. 7.

Fig. 10 is an enlarged view of the fixed end of the bourdon tube shown in fig. 9 viewed from the direction of arrow B.

Fig. 11 is a plan view of the relay board shown in fig. 6.

Fig. 12 is a side view of the relay board shown in fig. 11.

Fig. 13 is a longitudinal sectional view of the pointer shaft shown in fig. 6.

Fig. 14 is a front view of the pointer shaft shown in fig. 13.

Fig. 15 is a longitudinal sectional view of the bourdon shaft shown in fig. 6.

Fig. 16 is a front view of the bourdon shaft shown in fig. 15.

Figure 17 is a top view of the bimetal of figure 7.

Fig. 18 is a top view of the bimetal arm shown in fig. 7.

Fig. 19 is a side view of the bimetal arm shown in fig. 18 viewed from the direction of arrow C.

Fig. 20 is a side view of the relay sleeve shown in fig. 6.

Fig. 21 is a sectional view taken along line D-D shown in fig. 20.

Fig. 22 is a view showing a modification of the scale plate.

Fig. 23 is a view showing another modification of the scale plate.

Fig. 24 is a diagram showing a modification of the oil cap.

Fig. 25 is a side view showing a modification of the temperature indicating gauge, and is a view showing the temperature indicating portion facing upward.

Fig. 26 is a side view showing another modification of the temperature indicating gauge, and is a view showing the temperature indicating portion obliquely upward.

Fig. 27 is a front view showing still another modification of the temperature indicator, and is a view of the temperature indicator including a connection pipe having a flexible pipe.

Fig. 28 is an enlarged sectional view around the lower end portion of the flexible pipe shown in fig. 27.

Figure 29 is a side view of a body housing including around the upper end of the flexible pipe shown in figure 27.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In the present embodiment, a case where a temperature indicator is attached to an exhaust pipe through which exhaust gas discharged from a marine engine flows to measure the temperature of the exhaust gas is described as an example.

However, the location and use of the temperature indicator may be changed as appropriate.

As shown in fig. 1 and 2, the temperature indicator 1 of the present embodiment can be provided to the exhaust pipe 2 through a protective pipe 10, and the protective pipe 10 is attached to the attachment cylinder 3 formed on the exhaust pipe 2 through which the exhaust gas (the portion to be measured of the present invention) G flows.

The mounting cylinder 3 is formed in a cylindrical shape protruding outward from the exhaust pipe 2, and communicates the inside and outside of the exhaust pipe 2. A first female screw portion 3a is formed on the inner peripheral surface of the mounting tube 3.

In the present embodiment, the center axis of the mounting tube 3 coincides with the center axis of the temperature sensing tube 20 described below. Therefore, the common central axis is referred to as a temperature sensing shaft O1. The direction away from the exhaust pipe 2 along the temperature sensing axis O1 is referred to as upward, and the direction toward the exhaust pipe 2 opposite thereto is referred to as downward. Therefore, the direction along the temperature sensing axis O1 is the vertical direction L1. Further, one direction orthogonal to the temperature sensing axis O1 is referred to as a front-rear direction L2, and a direction orthogonal to both the vertical direction L1 and the front-rear direction L2 is referred to as a left-right direction L3. Further, in the front-rear direction L2, the direction in which the scale plate 25 described below faces is the front side or the front, and the opposite direction is referred to as the rear side or the rear.

(protective tube)

As shown in fig. 1 to 3, the protection tube 10 is made of, for example, stainless steel, and includes a protection tube main body 11 formed in a bottomed cylindrical shape and a fastening nut 12 fixed to an upper end portion of the protection tube main body 11.

The outer diameter of the protective tube main body 11 is formed smaller than the inner diameter of the mounting cylinder 3, and can be inserted into the exhaust pipe 2 from above through the mounting cylinder 3. A first external thread portion 11a that is screwed into the first internal thread portion 3a on the mounting tube 3 side is formed in a portion of the outer peripheral surface of the protective tube main body 11 that is located below the fastening nut 12. Therefore, the first external thread portion 11a is screwed into the first internal thread portion 3a, whereby the protection pipe body 11 can be integrally attached to the attachment cylinder 3 in a state of being inserted into the exhaust pipe 2 by a predetermined insertion amount.

Further, a metal (e.g., copper) spacer 13 is provided between the fastening nut 12 and the upper end opening end of the mounting tube 3. When the protective tube 10 is mounted on the mounting cylinder 3, the spacer 13 is sandwiched between and in close contact with the fastening nut 12 and the upper end open end of the mounting cylinder 3. Thereby, high sealability between the mounting cylinder 3 and the protective tube main body 11 is ensured. Further, the first female screw portion 3a and the first male screw portion 11a are configured to be tightly screwed with each other. In this regard, a high sealing property between the mounting cylinder 3 and the protective tube main body 11 is also ensured.

The fastening nut 12 is mainly used for screwing the first external thread portion 11a to the first internal thread portion 3a when fastening the protective tube 10 to the mounting tube 3, and is, for example, a hexagonal nut. A second female screw portion 12a that is screwed with a second female screw portion 42a of a tightening screw member 40 described below is formed on the inner peripheral surface of the fastening nut 12.

(temperature indicator)

As shown in fig. 1 to 3, the temperature indicator 1 includes: a temperature sensing part 21 having a temperature sensing cylinder 20; a main body case 22 provided above the temperature sensing unit 21; a straight tube-shaped lever (connection pipe in the present invention) 23 that integrally connects the temperature sensing cylinder 20 and the main body case 22; and a temperature indicating section 26 provided in the main body case 22 and having a pointer 24 and a scale plate 25.

Therefore, the temperature indicator 1 of the present embodiment is a direct-connection type in which the temperature sensing unit 21 is directly connected to the main body case 22 via the rod 23.

As shown in fig. 4, the temperature indicator 1 is configured such that the stem 23 and the temperature sensing cylinder 20 are inserted into the protective tube 10 from above, and the temperature sensing cylinder 20 can be installed in the exhaust pipe 2 through the protective tube 10. In contrast, by pulling out and separating the temperature indicator 1 from the protective tube 10, the temperature indicator 1 can be separated from the protective tube 10 while leaving the protective tube 10 on the exhaust pipe 2 side.

Accordingly, since the temperature indicator 1 can be combined with the exhaust pipe 2 by the protection pipe 10, the temperature indicator 1 can be easily attached and detached while the inside of the exhaust pipe 2 is maintained in a sealed state by the protection pipe 10.

Further, the temperature indicator 1 is integrally combined with the protective tube 10 by a below-described tightening screw member 40 and a fastening ring 45.

As shown in fig. 3 and 5, the temperature sensing unit 21 includes the above-described temperature sensing cylinder 20 and a plug 30 for closing an upper end opening of the temperature sensing cylinder 20.

The temperature sensing cylinder 20 is made of, for example, stainless steel, and is formed in a bottomed cylindrical shape having an upper opening. Further, as described above, the center axis line of the temperature sensing cylinder 20 (the temperature sensing shaft O1) is provided coaxially with the center axis line of the attachment cylinder 3 and the protection pipe 10.

In the present embodiment, in a plan view seen from the direction of the temperature sensing shaft O1, a direction intersecting the temperature sensing shaft O1 is referred to as a radial direction, and a direction surrounding the temperature sensing shaft O1 is referred to as a circumferential direction.

The outer diameter of the temperature sensing cylinder 20 is formed to be slightly smaller than the inner diameter of the protection pipe 10, and is formed in a bottomed cylindrical shape having a short length along the temperature sensing axis O1. The working fluid F is sealed inside the temperature sensing tube 20, and expands and contracts in accordance with the temperature of the exhaust gas G transmitted through the protection tube 10.

Further, the working fluid F may be, for example, an inert gas. However, various gases including gases other than inert gases may be used, and a liquid or the like may be used instead of the gas. In each of the drawings including fig. 3, the working fluid F is indicated by dot hatching. However, in order to make the drawings easy to understand, the working fluid F inside the temperature sensing cylinder 20 is shown only by dot hatching.

The plug 30 is made of, for example, stainless steel, is provided above the temperature sensing cylinder 20, and is formed in a multi-stage shaft shape in which the outer diameter changes in multiple stages along the temperature sensing shaft O1.

The plug portion 30 includes: a large diameter portion 31 having the same outer diameter as the temperature sensing cylinder 20 and contacting an upper end opening end of the temperature sensing cylinder 20; a first small diameter portion 32 provided below the large diameter portion 31 and formed to have an outer diameter smaller than that of the large diameter portion 31; and a second small diameter portion 33 provided above the large diameter portion 31 and formed to have an outer diameter smaller than that of the large diameter portion 31.

Further, the plug 30 is formed with a first through hole 34 that vertically penetrates the plug 30, coaxially with the temperature sensing shaft O1.

The first small diameter portion 32 is tightly fitted inside the temperature sensing cylinder 20. Thus, the plug 30 is combined with the temperature sensing cylinder 20 to close the upper end opening of the temperature sensing cylinder 20. The upper end opening end of the temperature sensing cylinder 20 and the large diameter portion 31 are fixed to each other by welding or the like over the entire circumference. Thereby sealing the inside of the temperature sensing cylinder 20.

The lever 23 is made of, for example, stainless steel, and is formed in a cylindrical shape extending along the temperature sensing shaft O1. The lever 23 has the same outer diameter as the temperature sensing cylinder 20 and is disposed above the temperature sensing cylinder 20 and the plug 30 in a state of being disposed coaxially with the temperature sensing shaft O1.

The rod 23 has a lower end opening end contacting the large diameter portion 31 in a state where the second small diameter portion 33 of the plug portion 30 is fitted inside. Thus, the rod 23 is combined with the plug 30 in a state where the lower end opening portion is closed by the plug 30. The lower end opening end of the stem 23 and the large diameter portion 31 are fixed to each other by welding or the like over the entire circumference. Therefore, the lever 23 and the temperature sensing cylinder 20 are combined in an integrally coupled state by the plug 30.

A rod coupling portion 35 made of, for example, stainless steel is attached to an upper end portion of the rod 23. The rod coupling portion 35 includes: a fastening nut 36 surrounding an upper end portion of the rod 23 from a radial outside; and a threaded shaft portion 37 formed to extend upward from the fastening nut 36.

The fastening nut 36 is mainly used to attach the rod coupling portion 35 to the main body case 22 when fastening the rod coupling portion 35, and is, for example, a hexagonal nut. The upper end portion of the rod 23 is tightly fitted inside the fastening nut 36. The nut 36 and the rod 23 are fixed to each other by welding or the like over the entire circumference. Thus, the rod 23 and the rod coupling portion 35 are combined in an integrally coupled state.

The threaded shaft portion 37 has an outer diameter smaller than that of the rod 23, and a third male threaded portion 37a is formed on an outer peripheral surface thereof. The third external screw thread portion 37a is screwed with a third internal screw thread portion 70a described below formed on the main body case 22 side. Therefore, the body case 22 and the lever 23 can be combined in a coupled state by the lever coupling portion 35 by screwing the third external screw thread portion 37a into the third internal screw thread portion 70 a.

Further, a spring washer 38 is attached to the threaded shaft portion 37, and the body case 22 and the rod coupling portion 35 are combined in a state of sandwiching the spring washer 38. Further, the rod coupling portion 35 is formed with a second through hole 39 which vertically penetrates the rod coupling portion 35, coaxially with the temperature sensing shaft O1.

The lever 23 and the temperature sensing cylinder 20 constructed as described above can be inserted into the protection tube 10 with the temperature sensing cylinder 20 facing downward, as shown in fig. 4. At this time, the tightening screw member 40 and the fastening ring 45 are externally mounted on the rod 23.

As shown in fig. 3 and 4, the tightening screw member 40 includes a fastening nut 41 surrounding the rod 23 from the radially outer side and a threaded shaft portion 42 extending downward from the fastening nut 41. The fastening nut 41 is mainly used for attaching the tightening screw member 40 to the protective tube 10 when tightening the tightening screw member 40, and is, for example, a hexagonal nut.

A second external thread portion 42a that is screwed into the second internal thread portion 12a on the protective tube 10 side is formed on the outer peripheral surface of the threaded shaft portion 42. Thus, the tightening screw member 40 can be integrally combined with the protective tube 10.

The fastening ring 45 is disposed inside the fastening nut 12 of the protective tube 10 so as to be sandwiched between the fastening screw member 40 and the protective tube 10 in the vertical direction L1. Therefore, when the protective tube 10 is fastened, the tightening screw member 40 can press the fastening ring 45 downward.

The fastening ring 45 is a slit ring made of metal (e.g., copper) divided in the circumferential direction. A part of the outer peripheral surface of the fastening ring 45 is a tapered surface having a tapered cross section that gradually extends radially inward as it goes downward. The tapered surface is in sliding contact with a tapered surface formed on the protective tube 10 side.

Thus, the tightening ring 45 can be deformed to be gradually narrowed as it is pushed down by the tightening screw member 40, and functions to press the rod 23 from the radially outer side.

Therefore, the rod 23 is held by the tightening screw member 40 and the fastening ring 45, and can be housed in the protective tube 10 in a state of being positioned in the up-down direction L1 and the radial direction. Therefore, the entire temperature indicator 1 is restricted from being inadvertently released from the protective tube 10, and is stored in the protective tube 10 with less rattling.

As shown in fig. 1 to 3, the main body case 22 is provided above the temperature sensing unit 21 and the lever 23 configured as described above.

The main body case 22 includes a bottomed cylindrical case 50 and a case cover 60 combined with the case 50, and forms a closed space S accommodating the respective components inside.

As shown in fig. 6 to 8, the housing 50 is made of aluminum, for example, and is formed in a top cylindrical shape with an open front. The housing 50 includes: the display device includes a rear wall 51, a peripheral wall 52 protruding forward from an outer peripheral edge of the rear wall 51, an indicator cylinder 53 provided on a front side of the peripheral wall 52, and a front wall 54 connecting a rear end of the indicator cylinder 53 and a front end of the peripheral wall 52.

The rear wall 51 is formed in a plate shape having a length in the up-down direction L1 longer than a length in the left-right direction L3, and an upper end edge portion and a lower end edge portion thereof are formed in a convex circular arc shape having a predetermined curvature. Of the peripheral walls 52, a pair of the peripheral walls 52 opposed to each other in the up-down direction L1 are formed as an upper wall 55 and a lower wall 56, and the upper wall 55 and the lower wall 56 are formed in a circular arc shape corresponding to the outer shape of the rear wall 51. Of the peripheral walls 52, the other pair of peripheral walls 52 opposed to each other in the left-right direction L3 are formed as flat side walls 57 extending in the up-down direction L1.

The indicator cylinder 53 has an outer diameter equivalent to the interval between the side walls 57 in the left-right direction L3, and is formed in a cylindrical shape extending in the front-rear direction L2. Therefore, the center axis of the indicator cylinder 53 intersects with the temperature sensing shaft O1.

The front wall 54 is provided to sandwich the indicator cylinder 53 from above and below. Thus, the front wall 54 is mainly formed to connect the rear end portion of the indicator cylinder 53 and the front end portion of the upper wall 55, and is also formed to connect the rear end portion of the indicator cylinder 53 and the front end portion of the lower wall 56.

The housing cover 60 includes: a cover main body 61 made of, for example, stainless steel, and a transparent plate 65, the cover main body 61 being combined with the housing 50 from the front, the transparent plate 65 being provided between the cover main body 61 and the housing cover 60 and closing the front opening of the housing 50.

As shown in fig. 6, the cover main body 61 includes: a surrounding cylinder 62 surrounding the indicator cylinder 53 from the outside and contacting the outer peripheral surface of the indicator cylinder 53; a flange wall 63 extending upward and downward from a rear end of the surrounding tube 62 and overlapping the front wall 54 of the housing 50 from the front; and an annular wall 64 bent inward from around the front end portion of the cylinder 62.

The surrounding tube 62 is formed longer than the indicator tube 53 in the front-rear direction L2. Thus, a predetermined gap is ensured in the front-rear direction L2 between the front end opening end of the indicator cylinder 53 and the annular wall 64 of the housing 50.

The transparent plate 65 is disposed between the front end opening end of the indicator cylinder 53 and the annular wall 64 with the above gap. An annular spacer is provided between the transparent plate 65 and the indicator cylinder 53. Thus, the transparent plate 65 is sandwiched between the front end open end of the indicator cylinder 53 and the annular wall 64 by the spacer 66.

The transparent plate 65 is made of, for example, inorganic glass, and is formed in a circular plate shape having a predetermined thickness. The transparent plate 65 is formed to have an outer diameter larger than the inner diameter of the annular wall 64 and smaller than the inner diameter of the surrounding cylinder 62.

Further, the spacer 66 is made of, for example, silicone rubber having a predetermined thickness and a predetermined hardness, and is formed in a ring shape having the same outer diameter as the inner diameter around the cylinder 62 and the same inner diameter as the inner diameter of the ring-shaped wall 64. In the illustrated example, the spacer 66 is formed thicker than the transparent plate 65, but is not limited thereto.

As shown in fig. 1 and 2, the housing cover 60 configured in the above manner is integrally combined by attaching the flange wall 63 to the front wall 54 of the housing 50 with the coupling screw 67.

Specifically, as shown in fig. 6, the transparent plate 65 and the spacer 66 are sandwiched between the annular wall 64 and the indicator cylinder 53 in the front-rear direction L2. Therefore, the transparent plate 65 and the gasket 66 close the front opening of the indicator cylinder 53 in a state where the inside of the indicator cylinder 53 is sealed. Further, an O-ring 68 is provided between the indicating cylinder 53 and the surrounding cylinder 62 to ensure sealability between the indicating cylinder 53 and the surrounding cylinder 62.

Therefore, the internal space of the main body case 22 structured as described above becomes the sealed space S which is appropriately sealed as described above.

As shown in fig. 6 to 8, a coupling hole 70 that vertically penetrates the lower wall 56 is formed in the lowest portion of the lower wall 56 in the housing 50. A third female screw portion 70a that is screwed with the third male screw portion 37a in the rod coupling portion 35 is formed on the inner peripheral surface of the coupling hole 70.

Therefore, as described above, the third male screw portion 37a and the third female screw portion 70a are screwed together, and the body case 22 and the rod 23 are combined in a state of being coupled by the rod coupling portion 35.

The third male screw portion 37a and the third female screw portion 70a are tightly screwed together, and high sealing performance between the third male screw portion 37a and the third female screw portion 70a is ensured.

An oil hole 71 that vertically penetrates the upper wall 55 is formed in the top of the upper wall 55 in the housing 50. A fourth female screw portion 71a is formed on the inner peripheral surface of the oil hole 71. An oil cap 72 is screwed to the oil hole 71 via an O-ring 73, and a fourth external thread portion 72a screwed to the fourth internal thread portion 71a is formed in the oil cap 72.

In addition, a high-viscosity oil (e.g., silicone oil) not shown is filled in the interior (sealed space S) of the main body case 22 through the oil hole 71.

As shown in fig. 6 and 8, a pivot hole 75 that penetrates the rear wall 51 in the front-rear direction L2 is formed in a central portion of the rear wall 51 in the housing 50. The pivot hole 75 is provided coaxially with the center axis of the indicating cylinder 53.

As shown in fig. 6 and 7, the closed space S of the main body case 22 configured as described above mainly houses: a rotary unit 90 having a bourdon tube 80, a capillary tube 100 connecting the bourdon tube 80 and the temperature sensing cylinder 20, and a temperature indicating section 26 having a pointer 24 and a scale plate 25.

The pointer 24 is configured to rotate about a rotation axis O2 provided coaxially with the center axis of the indicator barrel 53 in the housing 50. In the present embodiment, in a front view seen from the direction of the rotation axis O2, a direction intersecting with the rotation axis O2 is referred to as a radial direction, and a direction around the rotation axis O2 is referred to as a circumferential direction.

The rotating unit 90 includes: a bourdon tube 80 elastically displaced in accordance with a pressure change caused by expansion and contraction of the working fluid F; a pivot shaft (a rotation shaft portion in the present invention) 110 provided coaxially with the rotation axis O2; a pointer shaft (first rotating bracket in the present invention) 120 which is rotatably combined with the pivot shaft 110 about the rotation axis O2 and to which the pointer 24 is mounted; a bourdon shaft (second rotating bracket in the present invention) 130 rotatably combined with the pivot shaft 110 about the rotation axis O2 and connected with a free end (the other end in the present invention) 81 of the bourdon tube 80; and a connecting body 175 connecting the pointer shaft 120 and the Bowden shaft 130.

As shown in fig. 6, 7 and 9, the bourdon tube 80 is formed in a spiral shape at a predetermined number of turns around the rotation axis O2, and is elastically displaceable in the radial direction from the fixed end 82 (one end portion in the present invention) to the free end 81 as a whole.

The bourdon tube 80 is formed of, for example, copper or a copper alloy, and is formed in a hollow band shape having a small thickness in the radial direction over the entire length thereof, and is pressed flat. The total length of the bourdon tube 80 is set to a predetermined length, and when the bourdon tube 80 is elastically displaced with the diameter enlarged or reduced in the radial direction, a predetermined number of turns of a spiral shape are formed with a gap not in contact with each other.

Of both ends of the bourdon tube 80, the end provided on the outermost periphery side serves as a fixed end 82 of the connection capillary 100, and the end provided on the innermost periphery side serves as a free end 81 of the connection bourdon shaft 130.

As shown in fig. 9 and 10, the fixed end 82 of the bourdon tube 80 is an open end that can communicate with the inside of the capillary 100, and the working fluid F is introduced through the capillary 100. Instead, the free end 81 of the bourdon tube 80 is a closed end. Thus, the working fluid F is sealed within the bourdon tube 80.

An expansion part 83 expanded in a radial direction is partially formed on the fixed end 82 of the bourdon tube 80. An insertion space 84 into which the capillary 100 can be inserted is formed inside the expansion portion 83. Accordingly, the capillary tube 100 can be connected to the fixed end 82 of the bourdon tube 80 by the expansion portion 83.

The free end 81 of the bourdon tube 80 can move (rotational movement) about the rotational axis O2 as the bourdon tube 80 elastically displaces in the radial direction.

The bourdon tube 80 configured as described above is housed in the closed space S in a state where the bourdon shaft 130 connected to the free end 81 is positioned in the front-rear direction L2 in the direction of the rotation axis O2.

As shown in fig. 6, the pivot shaft 110 is made of, for example, stainless steel, and is formed in a cylindrical shape having a thin diameter. The pivot shaft 110 is fixed to the rear wall 51 of the housing 50 in the main body housing 22 through a pivot bearing 140 and a relay plate 150.

As shown in fig. 6, 11, and 12, the relay board 150 is a plate made of stainless steel called "torx" having a predetermined thickness, and is formed in a rectangular shape in plan view in which the length in the up-down direction L1 is longer than the length in the left-right direction L3. A through hole 151 that penetrates the relay board 150 in the front-rear direction L2 is formed in the central portion of the relay board 150. Further, a bottomed accommodation hole 152 that opens in one of the left-right directions L3 is formed in the relay board 150.

The relay plate 150 configured in this way overlaps the rear wall 51 from the front in a state where the through hole 151 communicates with the pivot hole 75 formed on the rear wall 51 of the housing 50.

As shown in fig. 6, the pivot bearing 140 includes: a shaft main body 141 tightly fitted inside the through hole 151 of the relay plate 150 and inside the pivot hole 75 formed on the rear wall 51 of the housing 50, respectively; and a threaded shaft portion 142 formed to protrude from the rear end portion of the shaft body 141 to the rear side of the rear wall 51.

The front end surface of the shaft main body 141 is flush with the front surface of the relay plate 150, and is fixed along the opening periphery of the through hole 151 by welding or the like. Thus, the pivot bearing 140 and the relay plate 150 are integrally combined.

The threaded shaft portion 142 is screwed with a coupling nut 145. At this time, the threaded shaft portion 142 is fitted with the seal washer 146 and the spring washer 147, and is screwed with the coupling nut 145 in a state where the seal washer 146 and the spring washer 147 are sandwiched between the rear wall 51 and the coupling nut 145. Accordingly, the sealing washer 146 and the spring washer 147 are pressed between the rear wall 51 and the coupling nut 145 as the coupling nut 145 is tightened.

Thus, the pivot bearing 140 and the relay plate 150 are firmly fixed to the rear wall 51 of the housing 50. Further, high sealing performance between the inside and the outside of the closed space S in the communication through-hole 151 and in the pivot hole 75 is ensured.

A front end surface of the pivot bearing 140 is formed with a shaft hole 143 that opens forward coaxially with the rotation axis O2. The inner diameter of the shaft hole 143 is the same as the outer diameter of the pivot shaft 110. The pivot shaft 110 is tightly fitted inside the shaft hole 143 by being fitted into the shaft hole 143. Thus, the pivot shaft 110 is fixed to the pivot bearing 140 through the shaft hole 143, and is disposed coaxially with the rotation axis O2. Further, the front end portion of the pivot shaft 110 is disposed inside the indicator cylinder 53 in the housing 50.

As shown in fig. 6, 7, 13, and 14, the pointer shaft 120 is made of, for example, brass, and is fitted to cover the pivot shaft 110 from the front. The pointer shaft 120 includes: a shaft cover 121 having a top cylindrical shape and surrounding the front end portion side of the pivot shaft 110 from the radial outside, and a retaining shaft 122 formed to extend forward from the shaft cover 121.

A slit-shaped groove 123 that opens in the front-rear direction L2 and the radial direction is formed in the peripheral wall portion of the shaft cover 121. The holding shaft 122 is formed in a small-diameter cylindrical shape provided coaxially with the rotation axis O2, and extends forward so as to protrude further toward the transparent plate 65 side than the inside of the indicator cylinder 53 of the housing 50.

The pointer shaft 120 configured in the above manner is fitted to cover the pivot shaft 110 from the front, thereby being capable of relative rotation with respect to the pivot shaft 110 about the rotation axis O2 in a state of being positioned in the front-rear direction L2. Further, the pointer 24 described below is held by using the holding shaft 122.

As shown in fig. 6, 15, and 16, the bourdon shaft 130 is made of, for example, brass, and is disposed between the pointer shaft 120 and the pivot bearing 140. The Bowden shaft 130 includes: a shaft main body 131 whose outer diameter is formed larger than, for example, the pointer shaft 120 and the pivot bearing 140; a front small diameter portion 132 provided on the front side of the shaft main body 131 and having an outer diameter smaller than that of the shaft main body 131; and a rear small diameter part 133 which is provided at a rear side of the shaft main body 131 and whose outer diameter is formed smaller than that of the shaft main body 131.

Further, a through hole 134 penetrating the bourdon shaft 130 in the front-rear direction L2 is formed in the bourdon shaft 130 coaxially with the rotation axis O2. Thus, the bourdon shaft 130 is provided between the pointer shaft 120 and the pivot bearing 140 in a state where the pivot shaft 110 is inserted into the through hole 134.

The shaft main body 131 is formed with a slit-shaped groove 135 that opens rearward. The free end 81 of the bourdon tube 80 is inserted into the groove 135 and fixed thereto by welding or the like. Thus, the free end 81 of the bourdon tube 80 and the bourdon shaft 130 are integrally connected. Further, a slip-off preventing ring 136 for restricting the free end 81 of the bourdon tube 80 from slipping out of the groove portion 135 is attached to the rear small diameter portion 133.

Therefore, with the elastic displacement of the bourdon tube 80 in the radial direction, the bourdon shaft 130 can rotate together with the free end 81 about the rotation axis O2.

As shown in fig. 6 and 7, the coupling body 175 couples the pointer shaft 120 and the bowden shaft 130 configured as described above, and rotates the pointer shaft 120 in accordance with the rotation of the bowden shaft 130.

The connecting member 175 includes: a bimetal 160, one end 161 of the bimetal 160 being connected to the pointer shaft 120; and a bimetal arm 170, the bimetal arm 170 being integrally combined with the bourdon shaft 130, and being connected to the other end 162 of the bimetal 160.

As shown in fig. 6, 7, and 17, the bimetal 160 is formed into a strip shape having a small thickness in the radial direction by combining the high expansion portion and the low expansion portion having different thermal expansion coefficients. In the example shown in the drawings, the bimetal 160 includes: a winding portion 163 partially double-wound around the rotation axis O2; and a straight portion 165 connected to the winding portion 163 by a bent portion 164 and extending in a radial direction.

The bimetal 160 configured in this way is provided as the shaft cover 121 surrounding the pointer shaft 120 from the radially outer side. The one end 161 of the bimetal 160 (i.e., the inner end of the coil 163) is inserted into the groove 123 formed in the shaft cover 121 and fixed thereto by welding or the like, for example. Thus, the one end 161 of the bimetal 160 and the pointer shaft 120 are integrally connected.

The other end portion 162 of the bimetal 160 (i.e., the outer end portion of the linear portion 165) is fixed to the bimetal arm 170 by, for example, welding or the like. Thus, the other end 162 of the bimetal 160 and the bimetal arm 170 are integrally connected.

As shown in fig. 6, 7, 18 and 19, the bimetal arm 170 includes: an annular plate 171 made of, for example, brass and fitted tightly and fixed to the front small diameter portion 132 of the Bourdon shaft 130; a first support arm 172 extending radially outward from the annular plate 171; and a second support arm 173 extending forward from an outer end of the first support arm 172.

Further, in the example shown in the drawings, the bimetal arm 170 includes: a pair of first and

second support arms

172 and 173 that face each other in the radial direction with the rotation axis O2 therebetween. But not limited thereto, each may have a first support arm 172 and a second support arm 173.

By fixing the annular plate 171 to the front small diameter portion 132, the bimetal arm 170 can rotate about the rotation axis O2 in accordance with the rotation of the bowden shaft 130. The second support arm 173 is formed in a double strand shape so as to have a slit-shaped groove portion 174. The other end 162 of the bimetal 160 is inserted into the groove 174 of the second support arm 173 and fixed thereto by welding or the like. Thus, the other end 162 of the bimetal 160 and the bimetal arm 170 are integrally connected.

Accordingly, the bimetal 160 may rotate about the rotation axis O2 together with the bimetal arm 170 along with the rotation of the bowden shaft 130.

Further, when the temperature inside the main body case 22 reaches a predetermined temperature or more, the bimetal 160 deforms in accordance with the temperature change inside the main body case 22, and the pointer shaft 120 can be rotated in the direction opposite to the rotational direction based on the elastic displacement of the bourdon tube 80 by the deformation.

As shown in fig. 6, the link body 175 constructed in the above-described manner connects the pointer shaft 120 and the bourdon shaft 130, the pointer shaft 120 is combined therewith in a state of being positioned in the front-rear direction L2 with respect to the pivot shaft 110, and the bourdon shaft 130 is connected to the free end 81 side of the bourdon tube 80. Therefore, the bourdon tube 80 and the bourdon shaft 130 are also disposed in the closed space S in a state of being positioned in the front-rear direction L2.

As shown in fig. 3, 6, and 7, the capillary tube 100 is a thin tube made of, for example, stainless steel, and connects the temperature sensing cylinder 20 and the bourdon tube 80 in a state where the inside of the temperature sensing cylinder 20 and the inside of the bourdon tube 80 are communicated with each other. Therefore, the working fluid F is also sealed in the capillary tube 100. That is, the working fluid F is sealed in the temperature sensing cylinder 20, the capillary tube 100, and the bourdon tube 80.

The capillary tube 100 is provided from the inside of the stem 23 to the inside of the closed space S, is connected to the temperature sensing cylinder 20 in the stem 23, and is connected to the fixed end 82 of the bourdon tube 80 in the closed space S.

The capillary 100 will be described in detail below.

The capillary tube 100 includes: a first capillary tube 101 connected to the temperature sensing cylinder 20, a second capillary tube 102 connected to the fixed end 82 of the bourdon tube 80, and a third capillary tube 103. The first capillary 101, the second capillary 102, and the third capillary 103 are combined in a state of communicating with each other through the relay member 180. In fig. 3 and 6, the first capillary 101, the second capillary 102, and the third capillary 103 are not illustrated or partially illustrated for the convenience of viewing the drawings.

The first capillary 101 is provided from the inside of the rod 23 to the inside of the closed space S. The portion of the first capillary 101 provided in the rod 23 passes through the second through hole 39 formed in the rod coupling portion 35, and enters the rod 23 from the closed space S side. The first capillary 101 has one end fitted into the first through hole 34 formed in the plug 30 in the rod 23, and is fitted into the first through hole 34.

Accordingly, one end of the first capillary tube 101 is connected to the temperature sensing cylinder 20 via the plug 30, and communicates with the inside of the temperature sensing cylinder 20. The other end of the first capillary 101 is connected to a relay sleeve 190 of the relay member 180, which will be described below, in the closed space S.

The first capillary 101 and the opening peripheral edge of the first through hole 34 are fixed to each other by brazing or the like over the entire periphery. Further, the first capillary 101 and the opening peripheral edge portion of the second through hole 39 are fixed by brazing or the like over the entire periphery.

The relay section 180 is explained here.

As shown in fig. 6, the relay unit 180 includes: a relay plate 150 fixed to the case 50 of the main body case 22 by the pivot bearing 140; and a relay sleeve 190 fixed in a state of being fitted into the receiving hole 152 of the relay board 150.

As shown in fig. 6, 20, and 21, the relay sleeve 190 is made of, for example, brass, and is a shaft main body having a circular outer shape and an outer diameter equal to an inner diameter of the receiving hole 152. The length of the relay sleeve 190 in the left-right direction L3 is smaller than the length (depth) of the accommodation hole 152 in the left-right direction L3.

The relay sleeve 190 has a first insertion hole 191, a second insertion hole 192, and a third insertion hole 19 formed therein, through which the relay member 180 axially penetrates and into which the first capillary 101, the second capillary 102, and the third capillary 103 can be inserted, respectively. The first, second, and third insertion holes 191, 192, and 193 are disposed at intervals.

As shown in fig. 6 and 7, the relay sleeve 190 configured in this way is fixed to the relay plate 150 by brazing or the like in a state of being tightly fitted inside the receiving hole 152. The other end of the first capillary 101 is fixed to the relay sleeve 190 by soldering or the like while being inserted into the first insertion hole 191 of the relay sleeve 190. Accordingly, the other end portion of the first capillary 101 is connected to the relay sleeve 190 in a state of communicating with the inside of the first insertion hole 191.

Further, the first capillary tube 101 is provided in the closed space S along the peripheral wall 52 of the housing 50 so as to surround the periphery of the rotating unit 90 including the bourdon tube 80.

The second capillary 102 is disposed between the relay sleeve 190 and the fixed end 82 of the bourdon tube 80 in the closed space S. One end portion of the second capillary 102 is inserted into the expansion portion 83 formed at the fixed end 82 of the bourdon tube 80. The one end portion of the second capillary 102 and the expansion portion 83 are fixed by brazing or the like. Accordingly, one end portion of the second capillary 102 is connected to the fixed end 82 of the bourdon tube 80 in a state of communicating with the inside of the bourdon tube 80.

The other end portion of the second capillary 102 is fixed to the relay sleeve 190 by brazing or the like in a state of being inserted into the second insertion hole 192 of the relay sleeve 190. Accordingly, the other end portion of the second capillary 102 is connected to the relay sleeve 190 in a state of communicating with the inside of the second insertion hole 192.

The third capillary 103 is provided in the closed space S, and one end portion thereof is fixed to the relay sleeve 190 by brazing or the like in a state of being inserted into the third insertion hole 193 of the relay sleeve 190. Accordingly, one end portion of the third capillary 103 is connected to the relay sleeve 190 in a state of communicating with the inside of the third insertion hole 193.

The third capillary 103 is housed in the closed space S in a state of being held by a holding member (not shown in the figure). Further, the other end portion of the third capillary 103 is in a closed state.

As described above, the first capillary 101, the second capillary 102, and the third capillary 103 are fixed to the relay sleeve 190 in a state in which they communicate with each other in the first insertion hole 191, the second insertion hole 192, and the third insertion hole 19. Therefore, the first capillary 101, the second capillary 102, and the third capillary 103 communicate with each other at the accommodation hole 152. Accordingly, the third capillary 103 communicates with the inside of the temperature sensing cylinder 20 and the inside of the bourdon tube 80 through the first capillary 101 and the second capillary 102, respectively.

The third capillary 103 serves as an introduction pipe for introducing the working fluid F into the temperature sensing cylinder 20 and the bourdon tube 80 through the first capillary 101 and the second capillary 102. After the working fluid F is introduced into the temperature sensing cylinder 20, the bourdon tube 80, and the capillary tube 100, the other end of the third capillary tube 103 is closed. Accordingly, the working fluid F can be easily and reliably sealed in the temperature sensing cylinder 20, the bourdon tube 80, and the capillary tube 100.

As shown in fig. 1 and 6, the temperature indicating section 26 includes a pointer 24 and a scale plate 25.

The pointer 24 is made of, for example, aluminum, and is tightly fitted to the holding shaft 122 of the pointer shaft 120 in a state of being disposed inside the spacer 66. Thus, the pointer 24 can rotate together with the pointer shaft 120 about the rotation axis O2, and can indicate the temperature according to the elastic displacement of the bourdon tube 80.

The scale plate 25 is made of, for example, aluminum, and is formed in a circular plate shape having a small thickness. The outer diameter of the scale plate 25 is formed larger than the inner diameter of the indication cylinder 53 and is formed smaller than the outer diameter of the indication cylinder 53. The scale plate 25 is provided between the shaft cover 121 of the pointer shaft 120 and the pointer 24, and its outer peripheral edge portion is sandwiched between the pointer cylinder 53 and the spacer 66 over the entire circumference in the front-rear direction L2. Thus, the scale plate 25 is disposed in the closed space S in a stably held state.

In addition, a relief hole 25a for inserting the holding shaft 122 of the pointer shaft 120 is formed in the center portion of the scale plate 25 coaxially with the rotation axis O2, and the scale plate 25 is penetrated in the front-rear direction L2.

As shown in fig. 1, a plurality of scales 25b indicating temperature are provided on the front surface of the scale plate 25 in a circumferential direction around the rotation axis O2. The scale 25b can be clearly indicated by various known means such as printing and engraving.

In the example shown in the figure, the scale 25b is provided so that the temperature can be indicated at intervals of 10 ℃ in a temperature region range (temperature range) of 50 ℃ to 650 ℃. In this case, the plurality of scales 25b are equally provided in the circumferential direction, i.e., so-called equal scales. Further, the scale 25b is provided such that a temperature range of 300 ℃ to 400 ℃ corresponding to a substantially middle temperature range of the temperature region range is located on the upper side of the scale plate 25.

(function of temperature indicator)

Next, a case where the temperature of the exhaust gas G is measured by the temperature indicator 1 configured as described above will be described.

As an initial state, as shown in fig. 1 to 3, in a state where the temperature sensing cylinder 20 and the lever 23 are properly inserted into the protection tube 10, the lever 23 is held by the tightening screw member 40 and the fastening ring 45. Accordingly, the temperature sensing cylinder 20 is provided at a predetermined position in the exhaust pipe 2 through the protection pipe 10.

In such an initial state, when the temperature of the exhaust gas G flowing through the exhaust pipe 2 changes, the working fluid F sealed in the temperature sensing cylinder 20 expands and contracts in accordance with the temperature of the exhaust gas G (in accordance with the change in temperature). Accordingly, the working fluid F in the capillary tube 100 and the bourdon tube 80 expands and contracts.

Accordingly, the spirally formed bourdon tube 80 can be elastically displaced so as to expand and contract in the radial direction in accordance with the pressure change caused by the expansion and contraction of the working fluid F. Therefore, the free end 81 of the bourdon tube 80 can be made to perform a circular movement (rotational movement) around the rotation axis O2 in accordance with the elastic displacement of the bourdon tube 80.

Therefore, the pointer 24 can be rotated about the rotation axis O2 with the elastic displacement of the bourdon tube 80.

Specifically, by the free end 81 of the bourdon tube 80 moving about the rotation axis O2, the bourdon shaft 130 can be rotated about the rotation axis O2 along with the free end 81. Thus, the entirety of the coupling body 175 having the bimetal arm 170 and the bimetal 160 rotates about the rotation axis O2, and the pointer shaft 120 can rotate about the rotation axis O2 in conjunction therewith. Therefore, the pointer 24 can rotate about the rotation axis O2 with the pointer shaft 120.

As a result, the temperature of the exhaust gas G can be indicated (temperature display) by the dial 25 and the pointer 24. For example, as shown in FIG. 1, a pointer 24 may be used to indicate a temperature around 250 ℃.

In particular, since the temperature sensing cylinder 20 and the bourdon tube 80 are connected by the capillary tube 100, as shown in fig. 6 and 7, the bourdon tube 80 does not need to extend to the temperature sensing cylinder 20 and can be left in the closed space S of the main body case 22. Therefore, the entire length of the bourdon tube 80 can be shortened as compared with the case where the bourdon tube 80 is directly connected to the temperature sensing tube 20. Therefore, the spiral bourdon tube 80 can be formed with a small number of turns, the outer diameter of the bourdon tube 80 as a whole can be reduced, and the bourdon tube 80 itself can be made compact.

Since the entire length is shortened to form a spiral shape with a small number of turns, and the bourdon tube 80 is downsized, the bourdon tube 80 can be elastically displaced with a good reaction even when the thermal expansion coefficient of the working fluid F is small, that is, even when the working fluid F slightly expands or contracts.

Therefore, as shown in fig. 3, the internal volume of the temperature sensing cylinder 20 for sealing the working fluid F can be reduced, and accordingly, the length of the temperature sensing cylinder 20 can be made shorter than in the related art. Therefore, the temperature sensing cylinder 20 can be miniaturized.

Further, since the length of the temperature sensing cylinder 20 can be shortened to achieve miniaturization, even if the exhaust pipe 2 is small in size and the temperature measurement region in the exhaust pipe 2 is narrow, for example, the temperature sensing cylinder can be easily and appropriately provided in the temperature measurement region. Further, since the temperature is measured based on the expansion and contraction of the working fluid F without using mercury or the like, the temperature can be accurately measured even if the exhaust gas G is at a high temperature. Therefore, even when the temperature measurement area is narrow and the exhaust gas G is high in temperature, the temperature measurement can be performed accurately.

Further, since the temperature sensing cylinder 20 and the bourdon tube 80 are connected by the capillary tube 100, not only the overall length, curvature, number of turns, and the like of the bourdon tube 80 can be easily set according to design as shown in fig. 7, but also the movement of the bourdon tube 80 can be concentrated on only the elastic displacement in the radial direction, and therefore the amount of the elastic displacement can be accurately controlled. Therefore, the accuracy of the measurement result can be improved.

Further, since a gearless system in which the pointer 24 is rotated by the elastic displacement of the bourdon tube 80 can be adopted without using a gear or the like, a measurement error due to gear engagement does not occur. In this regard, high accuracy of the measurement result can be achieved. In addition, the gear-free mode can be adopted, so that the durability is easily improved, and the service life of the product can be prolonged.

Further, since the size can be reduced by reducing the outer diameter of the bourdon tube 80, the internal volume of the sealed space S can be reduced, and the size of the main body case 22 itself can be reduced. For example, as shown in fig. 1, the lateral width W of the main body case 22 in the left-right direction L3 may be reduced to about 50 mm.

Therefore, the entire temperature indicator 1 can be miniaturized. Therefore, the temperature indicator 1 can be more easily applied to a place where it is difficult to secure an installation space, and can be applied to a ship engine.

Further, since the size of the main body case 22 can be reduced, the center of gravity of the entire temperature indicator 1 can be shifted downward toward the temperature sensing tube 20 side, and the center of gravity of the temperature indicator 1 can be lowered. Therefore, not only vibration resistance can be improved by miniaturization, but also visual recognition of the temperature indicating portion 26 including the pointer 24 can be improved.

Further, unlike the stick thermometer, since a dial system for indicating the temperature by rotating the pointer 24 about the rotation axis O2 can be adopted, reading is easier and visual recognition can be further improved.

As described above, according to the temperature indicator 1 of the present embodiment, not only can the temperature sensing cylinder 20 and the entire size be reduced, but also the temperature can be accurately measured even when the temperature measurement area is narrow and the exhaust gas G is high in temperature. Therefore, the temperature indicator is particularly suitable for ship engines.

Further, according to the temperature indicator 1 of the present embodiment, the following operational effects can be obtained.

That is, as shown in fig. 6, since the respective components of the bourdon shaft 130, the pointer shaft 120, the coupling body 175, the bourdon tube 80, and the pointer 24 can be compactly combined by the pivot shaft 110 combined with the main body case 22, it is possible to achieve stable operation performance while maintaining the accuracy of temperature indication even if the size of the main body case 22 is miniaturized.

Further, since the coupling body 175 has the bimetal 160, when the temperature in the main body case 22 becomes a predetermined temperature or more, the bimetal 160 can be deformed according to the temperature change, and the pointer shaft 120 rotated according to the rotation of the bourdon tube 130 can be rotated in the direction opposite to the rotation direction by the elastic displacement of the bourdon tube 80.

Accordingly, even if the bourdon tube is elastically displaced due to the influence of the temperature change in the main body case 22, the rotation of the pointer shaft 120 due to the temperature change in the main body case 22 can be eliminated. Thus, it is possible to correct a temperature error caused by a temperature change in the main body casing 22, and to cause the pointer 24 to indicate the temperature based only on the temperature change of the exhaust gas G even if the temperature in the main body casing 22 is, for example, at a high temperature. Therefore, the reliability of the measurement result can be further improved.

Further, since the scale plate 25 and the pointer 24 are oriented in the front direction different from the axial direction (the vertical direction L1) of the temperature sensing cylinder 20 and the lever 23, the visual recognition of the temperature indicating section 26 including the scale plate 25 and the pointer 24 can be improved as compared with, for example, the case of upward display.

Further, since the capillary tube 100 is constituted by the first capillary tube 101, the second capillary tube 102, and the third capillary tube 103 communicating with each other, it is possible to more easily and reliably connect the temperature sensing cylinder 20 and the bourdon tube 80, and to more easily seal the working fluid F.

In particular, by introducing the working fluid F into the third capillary 103, the working fluid F can be smoothly introduced into the cartridge 20 and the bourdon tube 80 through the first capillary 101 and the second capillary 102. Therefore, the working fluid F can be sealed in the temperature sensing cylinder 20, the capillary tube 100, and the bourdon tube 80 more easily and reliably. Therefore, even if the bourdon tube 80 is miniaturized, the working fluid F can be reliably sealed inside the bourdon tube 80, and the temperature measurement can be stably performed.

Further, since the relay member 180 can be used, the first capillary 101, the second capillary 102, and the third capillary 103 can be reliably combined in a state of communicating with each other.

That is, the first capillary 101, the second capillary 102, and the third capillary 103 may be integrally combined with the relay sleeve 190 by inserting and fixing the first capillary 101, the second capillary 102, and the third capillary 103 into the first insertion hole 191, the second insertion hole 192, and the third insertion hole 193 of the relay sleeve 190, respectively. Then, the relay board 150 and the relay sleeve 190 may be integrally combined by fitting the relay sleeve 190 into the receiving hole 152 and then fixing. Thus, the first capillary 101, the second capillary 102, and the third capillary 103 can be combined to the relay plate 150 fixed to the main body case 22 through the relay sleeve 190.

Therefore, the first capillary 101, the second capillary 102, and the third capillary 103 can maintain a stable posture without causing, for example, rattling in the main body case 22. Further, by fitting the relay sleeve 190 into the accommodation hole 152, the first capillary 101, the second capillary 102, and the third capillary 103 can be reliably communicated with each other in the accommodation hole 152.

(modification example)

In the above embodiment, the scale plate 25 in which the plurality of scales 25b, so-called uniform scales, are uniformly provided has been described as an example, but the present invention is not limited to this, and for example, as shown in fig. 22 and 23, the scales 25b, so-called non-uniform scales may be provided unevenly in a predetermined temperature range unit, or the scale plates 200,201 may be provided unevenly.

In the present embodiment, as described above, since the outer diameter of the bourdon tube 80 is suppressed to achieve miniaturization, it is considered that, for example, a change in the elastic displacement amount of the bourdon tube 80 with respect to a change in the temperature of the exhaust gas G does not change linearly. Even in this case, as shown in fig. 22 and 23, the scales 25b of the

scale plates

200 and 201 are set to be uneven in accordance with the amount of elastic displacement of the bourdon tube 80, whereby the temperature can be accurately indicated. Therefore, a more reliable temperature indication can be performed.

Further, when the scale plates 200,201 of uneven scale are used, for example, the bourdon tube 80 having different total lengths or numbers of turns is subjected to actual elastic displacement, and the amount of rotation change of the pointer 24 with respect to the temperature change is actually measured. At this time, it is determined how much a difference (for example, a temperature indication difference or an angle difference) is generated between the pointer 24 and the reference scale 25b, which are actually measured, with reference to the scales 25b evenly provided on the scale plate 25 shown in fig. 1.

Based on this result, the scale plates 200,201 of unequal scale as shown in fig. 22 and 23 can be obtained. In these

scale plates

200 and 201, the scale 25b is provided in such a manner that the temperature range per 100 ℃. For example, the graduations 25b are unequally arranged so that the temperature range of 100 ℃ to 200 ℃ is wider than the temperature range of 500 ℃ to 600 ℃.

In either case, even if the change in the amount of elastic displacement of the bourdon tube 80 with respect to the change in the temperature of the exhaust gas G is not a linear change, the temperature can be indicated more accurately by using the

scale plates

200 and 201 of uneven scale corresponding to the change in the amount of elastic displacement of the bourdon tube 80.

Further, in the above embodiment, the oil cap 72 formed on the upper wall 55 of the housing 50 may be a valved oil cap 210 capable of releasing pressure as shown in fig. 24.

The valved oil cap 210 includes a cap body 211, the cap body 211 including: a threaded shaft portion 212 having a fourth external thread portion 72a formed on an outer peripheral surface thereof, the fourth external thread portion 72a being screwed into the fourth internal thread portion 71a of the oil hole 71; and a nut portion 213 integrally formed at an upper end portion of the screw shaft portion 212.

The nut portion 213 is mainly used to screw the fourth external thread portion 71a into the fourth internal thread portion 71a when the valved cap 210 is fastened to the oil hole 71, and is, for example, a hexagonal nut.

The nut portion 213 has a first accommodation hole 215 that opens upward and is formed coaxially with the temperature sensing shaft O1. Further, a second accommodation hole 216 extending in the vertical direction L1 and opening upward through the first accommodation hole 215 is formed in the threaded shaft portion 212 coaxially with the temperature sensing shaft O1. In the example shown in the drawing, the inner diameter of the second receiving hole 216 is formed smaller than the inner diameter of the first receiving hole 215.

A first pressure release hole 217 is formed in the lower end portion of the threaded shaft portion 212 coaxially with the temperature sensing shaft O1, and the first pressure release hole 217 is formed to penetrate the threaded shaft portion 212 in the vertical direction L1 and to communicate the inside of the second accommodation hole 216 with the inside (the sealed space S) of the main body case 22. A cap 218 made of metal having a top cylindrical shape is tightly fitted inside the first accommodation hole 215, and the cap 218 closes the inside of the second accommodation hole 216 from above. A second pressure release hole 219 is formed in the cover portion 218 coaxially with the temperature sensing shaft O1, and the second pressure release hole 219 is formed to penetrate the cover portion 218 in the vertical direction L1 and to communicate the inside of the cover portion 218 with the outside.

With the above configuration, the interior of the second accommodation hole 216 communicates with the interior of the main body case 22 through the first pressure release hole 217, and communicates with the exterior through the second pressure release hole 219.

The bottom surface defining the second accommodation hole 216 is formed as a contact surface 220 having a tapered cross section that extends downward from the radially outer side toward the radially inner side.

In the second accommodation hole 216, a ball 221 that can abut on the contact surface 220 from above, and a coil spring 222 that presses the ball 221 from above and presses the ball 221 against the contact surface 220 are accommodated.

The ball 221 is made of, for example, synthetic rubber such as nitrile rubber having excellent oil resistance, wear resistance, and aging resistance, and is capable of closing the first pressure release hole 217 by pressing against the contact surface 220 and opening the first pressure release hole 217 by separating from the contact surface 220. The material of the ball 221 is not limited to synthetic rubber, and may be made of, for example, metal.

The coil spring 222 is made of, for example, stainless steel, and is disposed between the ball 221 and the cap 218 in a compressed state. The lower end of the coil spring 222 contacts the ball 221 from above, and the upper end thereof contacts the cover 218 from below while extending inside the cover 218. Accordingly, the coil spring 222 presses the ball 221 downward by its elastic restoring force, and presses the ball 221 against the contact surface 220.

Further, the coil spring 222 is adjusted in elastic force (spring force) so as to be elastically deformed until, for example, the pressure of the inside (the closed space S) of the main body case 22 is about to reach a predetermined upper limit value.

With the valved oil cap 210 configured as described above, at the time of measuring the temperature, for example, when the temperature inside the main body case 22 excessively rises and the internal pressure (internal pressure) reaches the vicinity of the upper limit value, the internal pressure acts on the ball 221 through the first pressure release hole 217, thereby pushing the ball 221 upward against the pressure applied by the coil spring 222. Thus, the ball 221 may be separated from the contact surface 220, and the first pressure release hole 217 may be opened. Therefore, the internal pressure can be released to the outside through the first relief hole 217 and the second relief hole 219, and the internal pressure of the main body case 22 can be suppressed from increasing beyond the upper limit value.

As described above, by providing the valved oil cap 210, excessive internal pressure rise in the main body case 22 can be suppressed at the time of temperature measurement.

Although the embodiments of the present invention have been described above, these embodiments are provided as examples and are not intended to limit the scope of the invention. The embodiments may be implemented in other various manners, and various omissions, substitutions, and changes may be made without departing from the spirit of the invention. The embodiment and its modifications include, for example, examples easily conceived by those skilled in the art, substantially the same examples, and examples of equal scope.

For example, although the case where the protective tube 10 is used has been described as an example in the above embodiment, the protective tube 10 is not essential and may not be provided.

Further, in the above embodiment, the temperature indicating unit 26 is configured to be displayed forward by being provided with the rotation axis O2 and the temperature sensing shaft O1 intersecting each other, but the present invention is not limited thereto.

For example, as shown in fig. 25, by attaching the lever 23 to the main body case 22 such that the rotation axis O2 is coaxial with the temperature sensing shaft O1, the temperature indicating section 26 including the pointer 24 can be displayed upward. Further, in this case, the upper end of the lever 23 is coupled to the rear wall 51 of the housing 50 of the main body housing 22 by the lever coupling portion 35.

Further, as shown in fig. 26, the temperature indicating section 26 including the pointer 24 may be displayed obliquely upward by connecting the main body case 22 to the lever 23 in an inclined state so that the rotation axis O2 is inclined at a predetermined angle with respect to the temperature sensing shaft O1. Further, in this case, the upper end portion of the lever 23 is coupled to the corner portions of the rear wall 51 and the lower wall 56 of the housing 50 of the main body housing 22 by the lever coupling portion 35.

Further, in the above-described embodiment, the rod 23 formed in a straight tube shape is described as an example of the connection pipe, but the invention is not limited thereto. For example, as shown in fig. 27, the temperature indicator 230 may further include a connection pipe 231 having a flexible pipe 232, and the flexible pipe 232 has flexibility.

The connection pipe 231 includes: a flexible tube 232 having flexibility over the entire length; a lower adapter member 233 for connecting the lower end of the flexible tube 232 to the temperature sensing unit 21; and an upper adapter member 234 for coupling the upper end of the flexible tube 232 with the main body housing 22.

The flexible tube 232 may be a long-sized serpentine tube made of, for example, stainless steel, and may be arbitrarily bent and deformed over the entire length.

As shown in fig. 27 and 28, the lower adaptor member 233 includes: a cylindrical adapter tube 240 extending along the temperature sensing axis O1; a first adaptor portion 250 coupled to an upper end portion of the adaptor tube 240; and a second transfer portion 260 disposed above the first transfer portion 250 and coupled to the first transfer portion 250.

The adapter tube 240 is made of, for example, stainless steel, and its lower end portion and the plug portion 30 in the temperature sensing portion 21 may be combined by being fixed by welding or the like. Therefore, the adapter tube 240 and the temperature sensing cylinder 20 are combined in a state of being integrally coupled by the plug portion 30.

The first transfer portion 250 is made of, for example, stainless steel, and includes: a first adapter tube 251 surrounding an upper end portion of the adapter tube 240 from a radial outside; and a threaded shaft portion 252 formed to extend upward from the first transfer cylinder 251.

The upper end of the adapter tube 240 is tightly fitted inside the first adapter tube 251. Further, the first adapter tube 251 and the adapter tube 240 are fixed to each other by welding or the like over the entire circumference. Thus, the first adapter tube 251 and the adapter tube 240 are combined in an integrally coupled state. The threaded shaft portion 252 has an outer diameter smaller than that of the first adapter tube 251, and a fifth male threaded portion 252a is formed on an outer peripheral surface thereof.

Further, a third through hole 253 that vertically penetrates the first transfer portion 250 is formed in the first transfer portion 250 coaxially with the temperature sensing shaft O1.

The second adapter portion 260 is formed in a cylindrical shape having the same outer diameter as that of the first adapter tube 251. A fifth female screw 260a that is screwed with the fifth male screw 252a is formed on the inner peripheral surface of the lower half portion of the second adapter 260 in the vertical direction L1. Thus, the first adaptor portion 250 and the second adaptor portion 260 are integrally combined by screwing the fifth external thread portion 252a and the fifth internal thread portion 260 a.

Further, the first transition portion 250 and the second transition portion 260 are fixed by welding or the like continuously or at intervals over the entire circumference. Thus, the first adaptor portion 250 and the second adaptor portion 260 are combined in an integrally coupled state.

The lower end portion of the flexible tube 232 is inserted from above into the upper half portion of the second adaptor portion 260 in the vertical direction L1. A set screw (set screw)261 called a "set screw" or the like is attached to the upper half of the second adaptor portion 260 in the vertical direction L1. The tip end portion of the set screw 261 is engaged with the bellows portion of the flexible tube 232. Thus, the flexible tube 232 is inserted into the second adapter 260 with the set screw 261 appropriately prevented from coming off.

Further, heat-resistant cement 262 or the like is filled inside the second adapter 260, and the lower end of the flexible tube 232 is firmly fixed. Thus, the flexible tube 232 and the second adaptor portion 260 are combined in an integrally coupled state. In fig. 27, the heat-resistant cement 262 is not shown.

As shown in fig. 27 and 29, the upper adapter member 234 includes the rod coupling portion 35 described above and an upper adapter portion 270 coupled to the rod coupling portion 35.

As described above, the rod coupling portion 35 is combined with the lower wall 56 of the main body case 22 with the spring washer 38 interposed therebetween. The upper adapter 270 has a structure similar to that of the second adapter 260, and the upper end thereof is tightly fitted inside the rod coupling portion 35. The rod coupling portion 35 and the upper adapter portion 270 are fixed to each other by welding or the like over the entire circumference. Thus, the rod coupling portion 35 and the upper adapter 270 are combined in an integrally coupled state.

The upper end of the flexible tube 232 is inserted from below into the inside of the upper adapter 270. At this time, the upper end portion of the flexible tube 232 is appropriately prevented from coming off by a set screw (not shown) provided to the upper adapter portion 270. Further, the inside of the upper adapter 270 is also filled with heat-resistant cement (not shown) or the like.

The inside of the connection pipe 231 constructed as described above is provided with the first capillary 101. The first capillary 101 enters the flexible tube 232 from the sealed space S side of the main body case 22 through the rod coupling portion 35. As shown in fig. 28, one end of the first capillary 101 is drawn out to the side of the temperature sensing cylinder 20 through the third through hole 253, and then connected to the temperature sensing cylinder 20. Accordingly, the inside of the first capillary tube 101 communicates with the inside of the temperature sensing cylinder 20.

With the above configuration, even if the temperature indicator 230 is provided with the connection pipe 231 having the flexible pipe 232, the same operational effect as that of the previously described temperature indicator 1 can be obtained.

Further, according to the temperature indicator 230, since the flexible tube 232 can be bent arbitrarily, the main body case 22 can be provided at a position away from the temperature sensing tube 20, for example. Therefore, the temperature indicator 230 can be used in different usage forms depending on the application, installation place, and the like, and is easy to use and improved in convenience.

In addition, in the temperature indicator 230 of this type, in order to facilitate attachment of the main body case 22, it is preferable that an attachment plate 280 is provided in the main body case 22 as shown in fig. 27 and 29.

The mounting plate 280 is, for example, a metal plate made of stainless steel, and is combined with the rear wall 51 of the casing 50 of the main body casing 22 by fastening screws 281 or the like. However, the mounting plate 280 is not essential and may not be provided, and the size, shape, and the like may be appropriately changed.

Description of the symbols

F. Working fluid

G. Exhaust (to be measured part)

S, closed space

O2, axis of rotation

1, 230, temperature indicator

15,200,201, scale plate

20. Temperature sensing cylinder

22. Main body shell

23. Rod (connecting pipe)

24. Pointer with a movable finger

25b, scale mark

26. Temperature indicating part

80. Bourdon tube

81. Fixed end of Bourdon tube (one end)

82. Free end (the other end) of Bourdon tube

100. Capillary tube

101. First capillary

102. Second capillary

103. Third capillary

110. Pivotal axis (rotating shaft)

120. Pointer shaft (first rotating support)

130. Bourdon shaft (second rotating bracket)

150. Relay board

152. Receiving hole

160. Bimetal

175. Connection body

180. Relay part

190. Relay sleeve

191. First through hole (through hole)

192. Second through hole (through hole)

193. Third through hole (through hole)

231. Connecting pipe

232. Flexible pipe

Claims

1. A temperature indicator, comprising:

a temperature sensing cylinder in which a working fluid is sealed, the working fluid expanding and contracting in accordance with a temperature of a portion to be measured;

a main body housing, in which a closed space is formed;

a connection pipe provided between the temperature sensing cylinder and the main body case and integrally connecting the temperature sensing cylinder and the main body case;

a bourdon tube disposed in the main body housing and elastically displaced according to a pressure change caused by expansion and contraction of the working fluid;

a capillary tube connecting the temperature sensing cylinder and the bourdon tube in a state where the inside of the temperature sensing cylinder and the inside of the bourdon tube are communicated;

a temperature indicating portion provided in the main body case and having a pointer and a scale plate indicating a temperature corresponding to elastic displacement of the bourdon tube;

the capillary tube is arranged from the inside of the connecting tube to the inside of the closed space, is connected with the temperature sensing cylinder in the connecting tube, and is connected with one end part of the Bourdon tube in the closed space,

the pointer is connected to the other end portion of the Bourdon tube and is rotatable about a rotation axis in accordance with elastic displacement of the Bourdon tube,

the Bourdon tube is formed in a spiral shape with a predetermined number of turns around the rotation axis as seen from the direction of the rotation axis, and is elastically displaceable in a radial direction,

the other end portion of the Bourdon tube is movable about the rotation axis in accordance with elastic displacement of the Bourdon tube,

the working fluid is sealed inside the capillary and inside the Bourdon tube.

2. The temperature indicator of claim 1,

the capillary tube includes:

a first capillary tube connected to the temperature sensing cylinder;

a second capillary tube connected to the one end portion of the bourdon tube; and

a third capillary tube;

the first capillary, the second capillary, and the third capillary are integrally combined in a state of being communicated with each other through a relay member,

the third capillary tube serves as an introduction tube for introducing the working fluid into the inside of the temperature sensing cylinder and the inside of the bourdon tube through the first capillary tube and the second capillary tube.

3. The temperature indicator of claim 2,

the relay member includes:

a relay board fixed to the body case and formed with a receiving hole; and

a relay sleeve fixed in a state of being fitted into the accommodation hole;

a plurality of insertion holes are formed in the relay sleeve, the plurality of insertion holes axially penetrate the relay sleeve, and the first capillary, the second capillary, and the third capillary can be inserted into the plurality of insertion holes,

the first capillary, the second capillary, and the third capillary are fixed in the insertion hole and communicate with each other in the accommodation hole.

4. The temperature indicator according to any one of claims 1 to 3,

the main body shell is internally provided with:

a rotation shaft portion that is combined with the main body case in a state of being provided coaxially with the rotation axis;

a first rotating bracket rotatably combined to the rotating shaft portion about the rotation axis and mounted with the pointer;

a second rotating bracket rotatably combined to the rotating shaft portion about the rotation axis and connected to the other end portion of the bourdon tube and positioning the bourdon tube in the rotation axis direction; and

a coupling body that couples the first rotating bracket and the second rotating bracket and rotates the first rotating bracket in accordance with rotation of the second rotating bracket.

5. The temperature indicator of claim 4,

the joint body includes a bimetal which combines a high expansion portion and a low expansion portion having different thermal expansion rates and which deforms in accordance with a temperature change when a temperature in the main body case reaches a predetermined temperature or higher,

the bimetal rotates the first rotating bracket in a direction opposite to a rotating direction based on elastic displacement of the Bourdon tube by deformation.

6. The temperature indicator according to any one of claims 1 to 5,

the scale plate is arranged such that scales indicating temperature are arranged in a circumferential direction around the rotation axis, and intervals of the scales are arranged unequally in a predetermined temperature range unit,

the scale is unevenly provided based on a change in an amount of elastic displacement of the bourdon tube with respect to a change in temperature of the portion to be measured.

7. The temperature indicator according to any one of claims 1 to 6, wherein the connection pipe is formed in a straight pipe shape extending in an axial direction of the temperature sensing cylinder.

8. The temperature indicator of claim 7, wherein the connecting tube is connected to the body housing in a manner intersecting the rotational axis.

9. The temperature indicator of any one of claims 1 to 6, wherein the connecting tube comprises a flexible tube having flexibility.