JPH11248584A - Arithmetic mechanism for instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an arithmetic mechanism for instrument which can synthesize the outputs of a plurality of instruments, for example, a pressure gauge and a thermometer and can output the product of the outputs. SOLUTION: An arithmetic mechanism has at least an input transmitting member 12, a scale factor cam 25, an arithmetic lever 13, a fulcrum member 17 for arithmetic lever, and a synthesized output transmitting member 22 and the arithmetic lever 13 is engaged with the fulcrum member 17, input transmitting member 12, and synthesized output transmitting member 22. The fulcrum member 17 is constituted so that the member 17 may be driven by means of the scale factor cam 25. In addition, the engaging sections of the arithmetic lever 13 engaged with the fulcrum member 17m and transmitting members 12 and 22 are constituted of notched sections 13a in which any two parts have parallel shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation mechanism of an instrument which combines outputs of a plurality of instruments, for example, a pressure gauge and a thermometer, and produces an output of the product.

[0002]

2. Description of the Related Art Conventionally, large-capacity switches and the like have been filled with oil such as PCB in a sealed container in order to ensure insulation. However, recently, due to pollution problems, SF6 gas-filled products are being replaced. A problem that arises when gas is used in a sealed container is detection of gas leakage. Since the gas pressure in the closed vessel changes depending on the temperature, it is not possible to immediately judge whether the fluctuation is due to the temperature or the fluctuation due to the gas leakage just by measuring the pressure. Therefore, a gas leak detection instrument which measures pressure and temperature simultaneously and converts the result into a state at the time of gas filling to detect whether or not there is an abnormality is required.

[0003] The relationship between the gas pressure (Pt) and the gas temperature (t) in the closed container is as follows: If the gas sealing pressure is (P0) and the pressure coefficient is (β), then Pt = (1 + βt) P0. When the stop pressure is determined, it is represented by a group of straight lines as shown in FIG. Then, when the gas temperature changes, for example, the gas sealing pressure is set to 0.
In order to operate the abnormality detection switch of the gas leak detection instrument at 4 MPa, 0.4 MPa (gas sealing temperature 2
It is necessary to turn on the switch at a point corresponding to the internal pressure of the gas, such as on a straight line (0 ° C.). Using the relationship between the pressure (Pt) and the temperature (t) of the gas in the closed container, a relational expression for obtaining the converted pressure (P20) at the time of arbitrary gas filling at 20 ° C. is obtained as P20 = (1 + 20β) × ｛Pt / ( 1 + β
t)｝ = {(1 + 20β) / (1 + βt)} × Pt, and the relationship between the gas-filled conversion pressure (P20), the temperature (t), and the gas pressure (Pt) in the closed vessel is determined via the pressure coefficient (β). The product has the form That is, an arithmetic operation mechanism of an instrument which combines the outputs of the pressure gauge and the thermometer of the gas in the closed container and generates an output of the product is required.

FIG. 7 summarizes the prior art.
A contact A52 is fixed to the gas pressure indicating pointer 51 in the closed container, and a contact B55 is fixed to the bimetal arm 54 on the standby side. When the gas temperature (in this case, the temperature in the instrument is substituted), the bimetal arm 54 on the standby side moves according to the characteristics of the bimetal.
The position of N is corrected.

[0005]

In the conventional correction method shown in FIG. 7, that is, a simple correction method in which the pressure change due to the temperature change is canceled by the movement of the bimetal, it is necessary to make the scale unequal intervals. Unless measures were taken, only the shape of the sum could be corrected, and it was impossible to cover the entire range of pressure and temperature changes in any narrow range. Naturally, it was not possible to convert the pressure into the state at the time of gas filling and display the pressure from the relationship between the pressure (Pt) and the temperature (t) of the gas in the closed vessel. Also, as shown in FIG. 6, since the gradient of the straight line changes according to the gas sealing pressure, it is necessary to change the characteristics of the bimetal each time in order to use the gas sealing pressure by changing the gas sealing pressure. It was not a mechanism to be done. Further, this mechanism has a drawback that the gas temperature cannot be directly measured because the bimetal cannot be put in the container due to its structure.

The problem to be solved by the present invention is that it is possible to convert the pressure (Pt) and temperature (t) of a gas in a closed vessel into an entire range of change and display the pressure in terms of the state at the time of gas filling. It is an object of the present invention to provide a mechanism, that is, an arithmetic operation mechanism of an instrument capable of combining respective outputs of a conventional pressure gauge and a thermometer and outputting a product thereof. Another object of the present invention is to provide an arithmetic mechanism capable of easily changing the gas sealing pressure when the gas sealing pressure is changed and used.

[0007]

In order to achieve the above object, the present invention comprises at least an input transmission member 12, a conversion coefficient cam 25, an operation lever 13, an operation lever fulcrum member 17, and a combined output transmission member 22, The operation lever 13 is engaged with the operation lever fulcrum member 17, the input transmission member 12, and the combined output transmission member 22, and the operation lever fulcrum member 17 is configured to be driven by the conversion coefficient cam 25. The engagement portion of the operation lever 13 which engages with the operation lever fulcrum member 17, the input transmission member 12, and the combined output transmission member 22 is formed of a cutout portion 13a having two parallel portions.

[0008]

Embodiment 1 Embodiment 1 will be described with reference to FIGS. Example 1
Indicates an arithmetic operation mechanism of an instrument that combines the outputs of the pressure gauge and the thermometer and can output the product. In FIG. 1, the frame 1, the frame 2 and the frame 3 are positioned by a column 4 and fixed with screws. A pressure pointer shaft gear 10 a is formed on the pressure pointer shaft 10, and a pressure pointer 11 is press-fitted at the tip of the pressure pointer shaft, and is supported by the frame 1 and the frame 2. The input lever 8 is fixed to the input lever shaft 9 and is supported by the frame 1 and the frame 2. An input transmission member 12 and a pressure transmission lever shaft 6 are fixed to the input lever 8 via a pressure transmission lever 5 and a seat 7. The pressure transmission lever 5 driven by the output of the pressure gauge can swing with respect to the pressure transmission lever shaft 6. A pressure pointer driving gear 8a is formed on a part of the input lever 8, and meshes with the pressure pointer shaft gear 10a.

A conversion coefficient cam 25 is fixed to a temperature pointer shaft 24 for transmitting the output of a thermometer using a Bourdon tube 23 of the thermometer. It is supported by the frame 2.
The fulcrum lever shaft 19 is fixed to the frame 1, and the fulcrum lever seat 18 that engages with the fulcrum lever shaft 19 is fixed to the fulcrum lever 16. An E-ring 15 is mounted on the fulcrum lever shaft 19 to restrict the axial movement of the fulcrum lever 16. The operation lever fulcrum member 1 is attached to the fulcrum lever 16.
7 is fixed, and the fulcrum lever 16 is
9 can be swung. The fulcrum lever 16 is engaged with the conversion coefficient cam 25 by a contact portion 16a shown in FIG.

An output lever 20 is fixed to the output lever shaft 21 and is supported by the frame 1 and the frame 2.
A combined output transmission member 22 is fixed to the output lever 20. An operation lever seat 14 is fixed to one end of the operation lever 13, the operation lever seat 14 is engaged with the input transmission member 12, and the E-ring 15 restricts the movement of the operation lever 13 in the axial direction. The operation lever 13 can swing with respect to the input transmission member 12. A notch 13a having a parallel shape is formed at the center and the other end of the operation lever 13, and the operation lever fulcrum member 17 is slidable at the center and the combined output transmission member 22 is slidable at the other end. Are engaged.

FIG. 2 shows a display mechanism and a signal generation mechanism of the composite output. A converted pressure pointer shaft gear 30a is formed on the converted pressure pointer shaft 30, and a converted pressure pointer 31 is press-fitted at the tip of the converted pressure pointer shaft, and the frame 1 and the lower limit needle pipe 3 are pressed.
4 and the like. A conversion pressure pointer driving gear 20a is formed on a part of the output lever 20, and meshes with the conversion pressure pointer shaft gear 30a. As the output lever 20 moves, the converted pressure indicator 31 rotates and displays the converted pressure value. In the signal generating mechanism, the micro switch 35 is turned on or off by the vertical movement of the upper limit cam gear 36 or the lower limit cam gear 37 at the position where the upper limit needle 33 or the lower limit needle 32 and the converted pressure pointer 31 coincide with each other, and a signal is generated. Upper limit needle 33
The signal generation pressure point can be arbitrarily set by setting the lower limit needle 32.

In FIG. 3, the conversion coefficient cam 25 operates when the temperature indicator 26 in FIG. 1 is at the same temperature as the gas sealing temperature, for example, 20 ° C.
The operation lever fulcrum member 17 is fixed to the temperature pointer shaft 24 such that the operation lever fulcrum member 17 is located at the center between the input transmission member 12 and the combined output transmission member 22. Next, the operation of the arithmetic mechanism will be described with reference to FIG. When the input lever 8 moves about the input lever shaft 9 by the output of the pressure gauge and the input transmission member 12 swings,
The operation lever 13 swings around the operation lever fulcrum member 17 and transmits the movement to the converted value output transmission member 22 through the cutout portion 13 a having a parallel shape, and the output lever 20 swings around the output lever shaft 21. I do. When the temperature indicator shaft 24 rotates according to the output of the thermometer, the conversion coefficient cam 25 rotates, the fulcrum lever 16 swings about the fulcrum lever shaft 19 through the contact portion 16a, and the calculation lever fulcrum member 17 has a parallel shape. It moves within the notch 13a. As a result, the amount of displacement of the output transmission member 22 corresponding to the amount of displacement of the input transmission member 12 changes.

The principle of obtaining a combined output is as follows. FIG. 4 is a diagram of FIG. Line segment AB
Is the position of the lever when the pressure is (0). The fulcrum C of the lever is located at the middle point of the segment AB when the gas temperature is 20 ° C., and is made to move on the segment AB when the temperature changes. When the pressure is (0), even if the temperature changes and the fulcrum C moves to C ',
The edges do not move. When the end A moves to A '(Pt), the end B moves to B' (P20). When the gas temperature is 20 ° C., the fulcrum C is a middle point, so that AA ′ (Pt) = BB ′ (P20). However, when the fulcrum C moves to C ′, the B end moves to B ″ and BB ″
(P20) = (b / a) × AA ′ (Pt). Therefore, if C ′ is made with the temperature output so that (b / a) = {(1 + 20β) / (1 + βt)}, the desired output is at the BB ′ end.

Embodiment 2 Embodiment 2 will be described with reference to FIG. FIG. 5 shows the first embodiment.
In contrast, the input lever 8, the fulcrum lever 16 and the output lever 20 can be moved linearly. The notch 13 a having a parallel shape of the operation lever 13 is provided at a portion that engages with the input transmission member 12 and the operation lever fulcrum member 17, and the operation lever 13 can swing with respect to the output transmission member 22. The input auxiliary lever 40 rotates about the input auxiliary lever shaft 41 and meshes with the pressure pointer driving gear 8a and the pressure pointer shaft gear 10a. Output auxiliary lever 4
Numeral 2 rotates about the output auxiliary lever shaft 43 and meshes with the reduced pressure pointer driving gear 20a and the reduced pressure pointer shaft gear 30a.

[0015]

According to the present invention, the input transmission member 12 is driven by the output of the pressure gauge, and the conversion coefficient cam 25 is driven by the output of the thermometer.
Is driven, and at least two of the engagement portions of the operation lever fulcrum member 17, the input transmission member 12, and the combined output transmission member 22 of the operation lever 13 are formed into cutout portions 13a having a parallel shape, and the conversion coefficient cam is formed. Since the operation lever fulcrum member 17 can move in accordance with the shape of the operation lever 25, the lever ratio of the operation lever 13 changes in accordance with the movement of the conversion coefficient cam 25, and the output converted to the state when gas is charged is taken out from the combined output transmission member 22. It became possible. Also, the relationship between the gas pressure (Pt) and the temperature (t) ｛(1 + 20β) / (1
+ Βt)｝ is replaced by the shape of the conversion coefficient cam 25, thereby removing the gas pressure fluctuation due to the temperature change in the entire range of the gas pressure (Pt) and temperature (t) changes in the closed vessel shown in FIG. The pressure, that is, the pressure converted to the state at the time of gas filling, can be displayed.

When the reference gas sealing temperature shown in FIG. 6 is changed, for example, from 20 ° C. to 30 ° C., the temperature indicator 2 shown in FIG.
When the temperature of 6 is 30 ° C., it is possible to cope only by fixing and changing the conversion coefficient cam 25 to the temperature pointer shaft 24 so that the operation lever fulcrum member 17 is located at the center between the input transmission member 12 and the composite output transmission member 22. . Further, when a gas having a different pressure coefficient (β) is used, only the conversion coefficient cam 25 needs to be newly replaced, so that it is possible to easily deal with a gas having a different pressure coefficient (β). In addition, even if the relationship between the gas pressure (Pt) and the temperature (t) is other than a straight line, it is possible to cope by changing the shape of the conversion coefficient cam 25.
Furthermore, it is possible to combine the outputs of not only the conventional pressure gauge and thermometer but also the two types of instruments and take out the product output.

[0017]

[Brief description of the drawings]

FIG.

FIG. 2 is a developed view showing the first embodiment of the present invention.

FIG. 3 is a plan view showing the first embodiment of the present invention.

FIG. 4 is a diagram showing the principle of the present invention.

FIG. 5 is a plan view showing a second embodiment of the present invention.

FIG. 6 is a diagram showing a relationship between gas pressure and gas temperature in a closed container.

FIG. 7 is a plan view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 12 Input transmission member 13 Operation lever 17 Operation lever fulcrum member 22 Synthetic output transmission member 25 Conversion coefficient cam 13a Notch having parallel shape

Claims (2)

[Claims] An operation lever includes at least an input transmission member, a conversion coefficient cam, an operation lever, an operation lever fulcrum member, and a combined output transmission member. An arithmetic operation mechanism for an instrument, wherein the arithmetic output lever fulcrum member 17 is driven by a conversion coefficient cam 25 while being engaged with the composite output transmission member 22. 2. An engaging portion of the operating lever 13, which engages with the operating lever fulcrum member 17, the input transmitting member 12, and the combined output transmitting member 22, is a cutout portion 13a having any two parallel portions. The arithmetic operation mechanism for an instrument according to claim 1, wherein: