JP2018018616A - Vacuum degree confirmation device and vacuum degree confirmation method for vacuum circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vacuum degree confirmation device and method capable of accurately confirming vacuum degree reduction of a vacuum valve regardless of a change in an installation environment of a vacuum circuit breaker by performing attachment/detachment and measurement of the vacuum degree confirmation device in a short time and safely when inspecting the vacuum circuit breaker.SOLUTION: A vacuum degree confirmation device comprises: a vacuum valve accommodated in a sealed container and including a movable contact and a stationary contact; a contact opening/closing operation mechanism for performing opening/closing operations on the movable contact and the stationary contact; and a load measuring device or a torque measuring device for measuring a load consisting of a total of a repulsive force of an opening spring for energizing the movable contact in a direction separated from the stationary contact and a self-closing force of the vacuum valve. The load measuring device or the torque measuring device is attached to the contact opening/closing operation mechanism in a freely removable manner, records and stores an atmospheric pressure and an initial measurement load in the atmospheric pressure when a vacuum circuit breaker is completely manufactured. When inspecting the vacuum circuit breaker, an inspection-time measurement load at the time of inspection is compared and collated with a correction load of the initial measurement load that is corrected in accordance with an atmospheric pressure at the time of inspection, thereby confirming a vacuum degree of the vacuum valve at the time of inspection.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vacuum degree confirmation device and a vacuum degree confirmation method for confirming the degree of vacuum in a vacuum valve in a vacuum circuit breaker used for power transmission and protection of power distribution facilities.

Conventional vacuum circuit breakers provide a pair of movable and fixed contacts that can be freely opened and closed inside a vacuum valve that can maintain a high degree of vacuum, thereby cutting off large currents due to the excellent insulation performance and interruption performance that a vacuum condition provides. It is possible. In addition, unlike the gas circuit breaker, SF ₆ gas having a high global warming potential is not used. Therefore, the application range of the vacuum circuit breaker has been expanded and the rated voltage has been increased.
On the other hand, if the vacuum level in the vacuum valve is reduced for some reason, the required insulation performance and interrupting performance cannot be maintained. For this reason, the vacuum level must be checked during periodic inspections of the vacuum circuit breaker. It has been. The conventional vacuum degree confirmation device and method is generally a method in which a leakage voltage is measured by applying a test voltage from the vacuum degree confirmation device between the two contacts with the movable contact and fixed contact in the vacuum valve open. It is.

JP 2004-158302 A Japanese Patent Laying-Open No. 2015-69954

In the vacuum circuit breaker confirmation method and method as described in the background art, since the test voltage is applied with the movable contact and fixed contact in the vacuum valve open, the vacuum circuit breaker is connected to the high voltage board. Pull out from the power supply, remove the power cable and overhead transmission line, or remove the grounding conductor after placing the grounding switches on both sides of the vacuum circuit breaker at the grounding position. It must be separated from the main circuit / ground circuit. Furthermore, in a vacuum circuit breaker with a high rated voltage, even if the degree of vacuum is reduced and the inside of the vacuum valve is replaced with an external gas such as air or SF ₆ gas, the circuit breaker is opened due to the insulating performance of the gas. Since the IEC standard indicates that there are cases where the contact between the contact points can withstand the test voltage, the distance between the contacts is temporarily suitable for the test voltage by adjusting the switching mechanism of the vacuum circuit breaker. Work to approach the position is also required. As a result, the power outage time of the power equipment required for the inspection work including the vacuum degree check is prolonged.

In patent document 1, it has the structure which can measure the load which acts on a movable rod by attaching a strain gauge to the movable rod which opens and closes the movable contact in a vacuum valve. Due to the pressure difference between the vacuum valve and the external gas, a load called a self-closing force is always applied in the direction in which the movable contact closes. When the movable contact is open, the self-closing force acts on the movable rod. Therefore, the decrease in vacuum is constantly monitored by measuring the load change with a strain gauge. However, since the movable rod has strength and rigidity that can withstand an impact load of several kN to several tens of kN that is generated every time the vacuum circuit breaker is opened and closed, several tens of N to several N that are generated due to a decrease in the degree of vacuum. With a load change of about 100 N, there is a possibility that the output fluctuation of the strain gauge cannot be detected.
Further, since the strain gauge is directly bonded to the movable rod, it is constantly exposed to shock and vibration due to the opening / closing operation of the vacuum circuit breaker. Or, when a vacuum circuit breaker is loaded with open / close, space propagation noise is generated due to surge voltage / current, so the lead wire extending from the strain gauge, the conversion device connected to it, and the notification device are affected by the space propagation noise. May result in false detection of a decrease in the degree of vacuum and failure of the apparatus. When these abnormalities occur at a higher probability than the vacuum degree drop of the vacuum valve, it is unsuitable as a vacuum degree confirmation device that constantly monitors the vacuum valve. Furthermore, since the strain gauge, the conversion device, and the notification device are permanently installed in the vacuum circuit breaker, it causes a cost increase.

  The vacuum circuit breaker of Patent Document 2 includes an opening / closing operation mechanism having a movable rod that linearly drives each of the three phases, and one of the movable rods is connected to a movable contact in a vacuum valve. A compressed open spring is connected to the other of the movable rods, and the load of the open spring overcomes the self-closing force of the vacuum valve, thereby holding the movable contact in the open position. During periodic inspections, the load measuring device is brought into contact with the rear end of the release spring, the release spring is pushed together with the movable rod in the direction in which the vacuum valve closes, and the load of the release spring and the self-closing force of the vacuum valve are subtracted The measured load is measured. In order to judge the soundness of the vacuum valve, when the vacuum circuit breaker was manufactured, it was compared with the initial load value measured in the same way, but considering the practical conditions of the vacuum circuit breaker, Since the gas pressure around the vacuum valve changes due to the difference in the ambient temperature, the temperature rise due to energization of the main circuit, etc., even if there is no abnormality in the degree of vacuum, the autistic force generated from the pressure difference with the surrounding gas fluctuates. Since this appears as a difference from the initial load value, the soundness of the vacuum valve may be determined erroneously. In addition, since the load measuring device must be attached and detached and the load measurement must be carried out for each of the three phases, the power outage time required for the power facilities is prolonged.

A vacuum degree confirmation device for a vacuum circuit breaker according to the present invention is housed in a sealed container filled with an insulating gas, and includes a vacuum valve having a movable contact and a fixed contact, and a contact opening / closing operation for opening and closing the movable contact and the fixed contact. Measures the load consisting of the sum of the repulsive force of the open spring and the self-closing force of the vacuum valve, which is provided in the operating mechanism and the contact opening / closing operating mechanism and urges the movable contact in the direction to release it from the fixed contact A vacuum circuit breaker confirmation device comprising a load measuring device or a torque measuring device, wherein the load measuring device or the torque measuring device is detachably attached to the contact opening / closing operation mechanism, and a vacuum When the circuit breaker is completed, the atmospheric pressure P ₀ and the initial measurement load F _{0 at the} atmospheric pressure P ₀ are recorded and stored. ₁ and a checking means for checking the degree of vacuum of the vacuum valve at the time of inspection by comparing and comparing the corrected load F ₀ ′ of the initial measurement load corrected in accordance with the atmospheric pressure P _A ′ at the time of inspection. It is what you are doing.

The vacuum degree confirmation method for a vacuum circuit breaker according to the present invention is a vacuum degree confirmation method implemented by the vacuum circuit breaker according to any one of claims 1, 2, 3, and 4. And
(1) Upon completion of the production of the vacuum circuit breaker, the load measuring device is pulled down by the tension mechanism 36b, and the movable contact 3 is moved in the direction of closing at least 0.1 mm from the open position, and the initial measurement load F generated by this movement An initial load measuring step for measuring ₀ ;
(2) an initial atmospheric pressure measuring step for measuring the atmospheric pressure around the sealed container at the time of the initial load measuring step;
(3) an initial value storing step for recording and storing the atmospheric pressure in the atmospheric pressure measuring step and the load in the initial load measuring step as initial values;
(4) An inspection load measurement step for measuring the inspection measurement load F ₁ applied to the spring rod corresponding to the initial measurement load F ₀ in the same manner as the initial load measurement step when the vacuum circuit breaker is inspected, (5) Atmospheric pressure measurement step during inspection to measure the atmospheric pressure around the sealed container at the time of the load measurement step during inspection,
(6) the initial measuring load F _0, the load correction step for correcting the inspection under load at atmospheric pressure P _{A 'when} inspected, and (7) when inspection of the vacuum circuit breaker, inspection during the measurement of the load at the time of inspection By comparing and comparing the load F ₁ and the corrected load F ₀ ′ of the initial measurement load corrected in accordance with the atmospheric pressure P _A ′ at the time of inspection, it is confirmed whether or not the vacuum degree of the vacuum valve is reduced at the time of inspection. This includes a verification check step.

  According to the vacuum degree confirmation device of the present invention, during the inspection, the vacuum circuit breaker is disconnected from the main circuit and ground circuit for power transmission and distribution, or the contact opening / closing operation mechanism is adjusted to temporarily reduce the distance between the contacts of the vacuum valve. Without applying a test voltage between the contacts, the load measuring device or the torque measuring device can confirm the vacuum degree drop of the vacuum valve in a short time and safely. In addition, since both the load measuring device and the torque measuring device are detachable and can be attached to the vacuum circuit breaker only at the time of inspection, the measuring device can always be managed in a healthy state, and the cost increase of the vacuum circuit breaker body can be suppressed. Can do. In addition, the initial values of the load and torque measured at the completion of production are corrected according to the environment at the time of inspection, and comparisons and judgments are performed, so the degree of vacuum can be accurately reduced regardless of changes in the installation environment of the vacuum circuit breaker. I can confirm. In the vacuum degree confirmation device of the present invention, it cannot be confirmed in any of the three-phase vacuum valves whether the degree of vacuum has been reduced. Such a confirmation is not necessarily required at the time of inspection because the whole needs to be replaced.

It is a side view which shows the state which installed the vacuum degree confirmation apparatus in Embodiment 1 of this invention in the vacuum circuit breaker in an open position. It is a top view which shows the vacuum circuit breaker in the open position of FIG. It is a side view which shows the state which installed the vacuum degree confirmation apparatus in Embodiment 2 of this invention in the vacuum circuit breaker in an open position. It is a side view which shows the state which installed the vacuum degree confirmation apparatus in Embodiment 3 of this invention in the vacuum circuit breaker in an open position. It is a top view which shows the state which installed the vacuum degree confirmation apparatus in Embodiment 4 of this invention in the vacuum circuit breaker in an open position.

The vacuum degree confirmation device according to the present invention is implemented in either single phase or three phase. In the case of three phases, a three-phase collective drive type contact opening / closing operation mechanism (see, for example, Patent Document 2) and A three-phase shaft that is connected to the contact opening / closing operation mechanism via a link and rotates, a movable rod that is connected in parallel to the three phases of the three-phase shaft and moves linearly at the same time, and the same axis as the movable rod The connected movable conductor is provided with a three-phase vacuum valve for opening and closing the movable contact and the fixed contact in vacuum via a first bellows that maintains vacuum airtightness, and an open spring rod is further connected to the three-phase shaft. A vacuum circuit breaker in which an open spring is biased in a direction to separate the movable contact from the fixed contact in a three-phase manner between the open spring rod and the fixed open spring receiver; and the open spring rod Load to measure the load urging Constant device, or with freely provided removably either the torque measuring device for measuring a torque which urges the ends of the three-phase axis, the atmospheric pressure P ₀ at the time of the vacuum circuit breaker manufactured completion, the location Paying attention to the atmospheric pressure P _A ′ when checking the vacuum circuit breaker, the load measuring device or the torque measuring device and the barometer are used to determine the initial value of the load or the torque and the atmospheric pressure when the vacuum circuit breaker is manufactured. Record and compare the measured value of the load or torque at the time of inspection with the initial value corrected according to the environment (atmospheric pressure) at the time of inspection. This is to confirm whether or not the decrease of the occurrence has occurred.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In addition, the same code | symbol shows the same or an equivalent part between each figure.

Embodiment 1 FIG.
A first embodiment of the present invention will be described with reference to FIGS.
1 is a side view showing a state in which the vacuum degree confirmation device according to Embodiment 1 of the present invention is installed in a vacuum circuit breaker at an open position, and FIG. 2 is a plan view showing the vacuum circuit breaker.

1 and 2, the vacuum circuit breaker according to the first embodiment of the present invention has a three-phase collective drive type contact opening / closing operation mechanism and a three-phase in a sealed container 1 in which an insulating gas is pressurized and sealed. A vacuum valve 2 is accommodated, and each has a pair of movable contact 3 and fixed contact 4 that can be contacted and separated in vacuum in the vacuum valve 2.
The hermetic container 1 has an opening covered with a base plate 5, and an insulating holder 6 made of an insulating material is attached to the inside of the base plate 5 for three phases. The insulating holder 6 has a fixed terminal 7 that is a current-carrying portion at the tip, and a fixed conductor 8 connected to the fixed contact 4 of the vacuum valve 2 is connected to the fixed terminal 7. Is supported by insulation.

  The movable conductor 9 connected to the movable contact 3 of the vacuum valve 2 penetrates the first bellows 10 which can expand and contract in an airtight manner, so that the movable contact 3 can be connected from the outside of the vacuum valve 2 while maintaining the vacuum state in the vacuum valve 2. It can be opened and closed. Further, a first movable rod 11, an insulating rod 12 made of an insulating material, and a second movable rod 13 are connected to the movable conductor 9 on the same axis, and the second movable rod 13 is a base. The movable contact of the vacuum valve 2 from the outside of the hermetic container 1 while holding the insulating gas pressurized and sealed in the hermetic container 1 by hermetically penetrating the second bellows 14 that can be stretched and attached to the plate 5 3 can be opened and closed. The shunt conductor 16 connected to the movable terminal 15 attached to the movable conductor 9 is a current-carrying portion, but is a member in which flexible copper strips are laminated, and does not hinder the opening / closing operation of the movable contact 3.

  In the first bellows 10 described above, the movable contact 3 is provided by a pressure difference between the vacuum in the vacuum valve 2 and the pressure of the external gas, that is, the pressure of the insulating gas pressurized and sealed in the sealed container 1 here. A load is generated in the closing direction. On the contrary, a load is generated in the second bellows 14 in the direction in which the movable contact 3 opens due to the pressure difference between the pressure of the insulating gas and the atmospheric pressure around the sealed container 1. Here, if the first bellows 10 and the second bellows 14 have the same effective cross-sectional area, the loads due to the pressure of the insulating gas cancel each other, and the vacuum inside the vacuum valve 2 and the atmospheric pressure around the sealed container 1 Only the load in the direction in which the movable contact 3 is closed remains, and this is the self-closing force of the vacuum valve 2.

On the other hand, an operation mechanism frame 17 exists outside the base plate 5, and a three-phase collective drive contact opening / closing operation mechanism 18 is attached.
The contact opening / closing operation mechanism 18 includes, for example, an opening spring 26, a closing spring, and a latch mechanism (not shown), holds a load of the stored opening spring 26 with a latch mechanism, and is operated at an arbitrary timing according to a contact opening / closing operation command. This is a mechanism for opening and closing the circuit breaker by releasing the latch and releasing the spring.
The contact opening / closing operation mechanism 18 transmits operating force from the output lever 20 rotating about the output shaft 19 to the three-phase vacuum valve 2 via the output link 21, the three-phase shaft lever 22, and the three-phase shaft 23. However, the output lever 20 and the output link 21 are unloaded at the opening position of the vacuum circuit breaker, and the opening is fixed to the operation mechanism frame 17 and the movable opening spring rod 24 connected to the three-phase shaft lever 22. An open spring 26 inserted in a compressed state between the spring receivers 25 pushes up the open spring rod 24 by its repulsive force. The pushed open spring rod 24 rotates the three-phase shaft 23 clockwise via the three-phase shaft lever 22 and is connected to the opposite side of the three-phase shaft lever 22 across the three-phase shaft 23. A contact pressure spring portion 28A composed of the rod 27, the contact pressure spring 28, and the contact pressure spring link 29 is pushed down. The contact pressure spring 28 is a member for pressing the movable contact 3 against the fixed contact 4 with a constant contact pressure at the closing position of the vacuum circuit breaker, and is therefore unloaded at the opening position.

  The pressed contact pressure spring portion 28A rotates the rotary lever 31 counterclockwise about the rotary lever pin 30 so that the movable contact 3 opens the conversion block 32 attached to the tip of the second movable rod 13. And the repulsive force of the open spring 26 is transmitted. At this time, the repulsive force of the opening spring 26 transmitted to the conversion block 32 is larger than the three-phase self-closing force of the vacuum valve 2, so that the vacuum circuit breaker is held in the open position. The opening position is always a constant position when the three-phase shaft lever 22 comes into contact with the stopper bolt 33 fixed to the operation mechanism frame 17 and the rotation of the three-phase shaft 23 is stopped. 38 is a movable side connection conductor, 39 is a movable side bushing, 40 is a movable side bushing internal conductor, 41 is a conversion block connection pin, 42 is a contact pressure spring link connection pin, 43 is an output lever connection pin, and 44 is an output link. Connection pin, 45 is an open spring rod connection pin, 46 is a contact pressure spring rod connection pin, 47 is a fixed-side bushing internal conductor, 48 is a fixed-side bushing, and 49 is a fixed-side connection conductor.

The vacuum degree confirmation device and the vacuum degree confirmation method of the vacuum circuit breaker will be described in detail.
First, the vacuum degree confirmation apparatus according to the first embodiment will be described.
The load measuring device 35 is constituted by a pressing mechanism 36a or a pulling mechanism 36b, and the load is measured by moving the vacuum valve 2 in the three-phase closing direction by the pressing mechanism 36a or the pulling mechanism 36b. This is to confirm whether a decrease in the degree of vacuum has occurred in any of the three phases of No. 2. Although not shown, the pressing mechanism 36a or the pulling mechanism 36b is constituted by a screw mechanism or a lever mechanism, and is a combination of a shaft simply connected to the load measuring device 35 and a linear bearing that guides this shaft in the thrust direction. Thus, the load is measured by grasping and pushing the shaft.
The screw mechanism measures the load by pushing and pulling the shaft by applying a male thread to the tip of the shaft and tightening a combination of nuts having a female screw of the same size.
The lever mechanism connects the middle part of the rod-shaped lever to the tip of the shaft, fixes one end of the lever using that part as the lever action point, and pushes the shaft by operating the other end of the lever. The load is measured by pulling.

The load measuring device 35 is detachably attached. At the opening position of the vacuum circuit breaker, the end of the open spring rod 24 is exposed from the bottom of the operation mechanism frame 17, and the detachable joint is provided. 34 is connected to one of the load measuring devices 35 through 34. A tension mechanism 36 for pulling down the open spring rod 24 is connected to the opposite side of the load measuring device 35 for each load measuring device 35, and the tension mechanism 36 b is operated by a detachable measuring frame 37. 17 is fixed.

Next, the vacuum degree confirmation method will be described.
After completion of the production of the vacuum circuit breaker, the load measuring device 35 is set, and the open spring rod 24 is pulled down together with the load measuring device 35 by the tension mechanism 36b, and the movable contact 3 is moved in the direction of closing at least 0.1 mm from the open position. Then, the load F ₀ [N] to push up the open spring rod 24 is measured by the load measuring device 35.

here,
Spring constant of the open spring 26: K _S [N / mm]
Deflection from the natural length of the open spring 26: X _S [mm]
Lever ratio from the second movable rod 13 to the open spring rod 24: L [−]
Effective sectional area of the first bellows 10 and the second bellows 14: S _B [mm ² ]
Atmospheric pressure around the sealed container 1 (absolute pressure): P _A [Pa]
Vacuum pressure in vacuum valve 2 (absolute pressure): P _V [Pa]
First bellows 10, the spring constant of the second bellows _{14: K B [N / mm} ]
Deflection from natural length of first bellows 10 and second bellows 14: X _B [mm]
Then, the load F ₀ [N] is expressed by the following formula (1).

_{F 0 = K S * X S} - 3 * L * {S B * (P A - P V) + 2 * K B * X B} ...
... (1)

When the production of the vacuum circuit breaker is completed as described above, the initial value of the atmospheric pressure P ₀ [Pa] is measured and recorded using the load F ₀ [N] and a general barometer with the above-described degree of vacuum confirmation device. When the storage is completed, since the joint 34 and the measurement frame 37 are detachable, the vacuum circuit breaker is used with the vacuum degree confirmation device removed.

At the time of inspection, the vacuum degree check device is attached to the vacuum circuit breaker again, and the load F ₁ [N] applied to the open spring rod 24 is measured as described above. At this time, except for the atmospheric pressure P ₀ [Pa] in the formula (1), the value is determined as a design value or a control value in manufacturing without depending on the use condition of the vacuum circuit breaker. If the surrounding atmospheric pressure (absolute pressure) is P _A ′ [Pa], the load F ₁ [N] is expressed by the following equation (2).

_{F 1 = K S * X S} - 3 * L * {S B * (P A '- P V) + 2 * K B * X B} ...
... (2)

The atmospheric pressure P _A ′ [Pa] varies depending on the use environment of the vacuum circuit breaker. For example, at an altitude of 1000 m, which is one of the normal track use conditions of the circuit breaker defined in the IEC standards, it is compared with an altitude of 0 m. Atmospheric pressure is reduced by about 10%. Furthermore, the atmospheric pressure changes depending on weather conditions such as temperature, and these also affect the self-closing force of the vacuum valve 2, so the initial pressure after measuring the atmospheric pressure P _A '[Pa] at the time of inspection The load F ₀ [N] is corrected to the load F ₀ '[N] by the following equation (3), and then compared with the load F ₁ [N] at the time of inspection.

_{F 0 '= F 0 + 3} * L * S B * (P A - P A') ...... (3)

If there is no abnormality in the degree of vacuum of the vacuum valve 2, the loads F ₀ ′ [N] and F ₁ [N] should show equivalent values.
However, if the air-tightness of one phase of the three-phase vacuum valve 2 is broken and the vacuum valve 2 is completely replaced with the insulating gas having the same pressure as the sealed container 1, the insulating gas pressure (absolute pressure) is reduced. If P _G [Pa] is set, the load F ₁ ′ [N] increases from the load F ₀ ′ [N] as expressed by the following equation (4), so that a decrease in the degree of vacuum can be confirmed. .

_{F 1 '= F 0' +} L * S B * P G ...... (4)

  In the first embodiment, the description has been given mainly based on the load measuring device 35, but the present invention can also be appropriately implemented by a torque measuring device 54 described later.

Embodiment 2. FIG.
A second embodiment of the present invention will be described with reference to FIG.
FIG. 3 is a side view showing a state in which the vacuum degree confirmation device according to Embodiment 2 of the present invention is installed in the vacuum circuit breaker at the open position.

In FIG. 3, the vacuum circuit breaker according to the second embodiment has substantially the same structure as the vacuum circuit breaker according to the first embodiment, except that the second movable rod 13 is different from the first embodiment. Board 5
By air-tightly penetrating the sliding seal (alternate part of the second bellows 14) 50 attached to the vacuum vessel 2 from the outside of the sealed vessel 1 while holding the insulating gas pressurized and sealed in the sealed vessel 1 The movable contact 3 can be opened and closed.

  Similar to the vacuum circuit breaker according to the first embodiment, the first bellows 10 in the vacuum valve 2 has a movable contact due to the pressure difference between the vacuum and the pressure of the insulating gas pressurized and sealed in the sealed container 1. A load is generated in the direction in which 3 closes. On the other hand, since the load due to the pressure difference between the pressure of the insulating gas and the atmospheric pressure around the sealed container 1 does not occur in the sliding seal 50, the load due to the pressure difference between the vacuum and the insulating gas is closed by the vacuum valve 2. It becomes power.

Next, a method for confirming the degree of vacuum of the vacuum circuit breaker will be described.
The configuration of the vacuum degree confirmation device is the same as that of the first embodiment. After the completion of the production of the vacuum circuit breaker, the load measuring device 35 is set and the open spring rod 24 is pulled down together with the load measuring device 35 by the tension mechanism 36b. Is moved in the direction of closing at least 0.1 mm from the opening position, and the load F ₀ [N] to push up the open spring rod 24 is measured by the load measuring device 35.

here,
Spring constant of the open spring 26: K _S [N / mm]
Deflection from the natural length of the open spring 26: X _S [mm]
Lever ratio from the second movable rod 13 to the open spring rod 24: L [−]
Effective cross-sectional area of the first bellows 10: S _B [mm ² ]
Insulating gas pressure in the sealed container 1 (absolute pressure): P _G [Pa]
Vacuum pressure in vacuum valve 2 (absolute pressure): P _V [Pa]
Spring constant of the first bellows 10: K _B [N / mm]
Deflection from the natural length of the first bellows 10: X _B [mm]
Then, the load F ₀ [N] is expressed by the following equation (5).

_{F 0 = K S * X S} - 3 * L * {S B * (P G - P V) + K B * X B} ... (5)

In the above vacuum check device when the vacuum circuit breaker manufactured complete by utilizing such load F ₀ [N] and a pressure gauge to measure the initial value of the insulating gas pressure P _G [Pa], After completion of recording storage, joint 34 Since the measurement frame 37 is detachable, the vacuum circuit breaker is used with the vacuum degree confirmation device removed. Note that the pressure gauge used here does not perform temperature compensation.

At the time of inspection, the vacuum degree check device is attached to the vacuum circuit breaker again, and similarly the load F ₁ [N] applied to the open spring rod is measured. At this time, except for the insulating gas pressure P _G [Pa] in equation (5), the value is determined as a design value or a control value in manufacturing, regardless of the use conditions of the vacuum circuit breaker. If the insulating gas pressure (absolute pressure) in 1 is P _G '[Pa], the load F ₁ [
N] is represented by the following formula (6).

_{F 1 = K S * X S} - 3 * L * {S B * (P G '- P V) + K B * X B} ... (6)

The insulating gas pressure is strongly affected by the temperature change of the insulating gas due to the ambient temperature of the vacuum circuit breaker, solar radiation, and heat generated by energizing the main circuit. Since this also affects the self-closing force of the vacuum valve 2, the initial load F ₀ [N] is measured by the following equation (7) after measuring the insulating gas pressure P _G '[Pa] at the time of inspection. _After correcting to ₀ '[N], the load F ₁ [N] at the time of inspection is compared.

_{F 0 '= F 0 + 3} * L * S B * (P G - P G') ...... (7)

If there is no abnormality in the vacuum degree of the vacuum valve 2, the loads F ₀ '[N] and F ₁ [N] should show the same value, but if one of the three-phase vacuum valves 2 is broken, the air-tightness of one phase is broken. When the inside of the vacuum valve 2 is completely replaced with the insulating gas having the same pressure as the inside of the sealed container 1, the load F ₁ '[N] is obtained from the load F ₀ ' [N] as expressed by the following equation (8). Since it increases, the fall of a vacuum degree can be confirmed.

_{F 1 '= F 0' +} L * S B * P G '...... (8)

  Although the second embodiment has been described mainly based on the load measuring device 35, the present invention can also be appropriately implemented by a torque measuring device 54 described later.

Embodiment 3 FIG.
A third embodiment of the present invention will be described with reference to FIG.
FIG. 4 is a side view showing a state in which the vacuum degree confirmation device according to Embodiment 3 of the present invention is installed in the vacuum circuit breaker at the open position.

In FIG. 4, the vacuum circuit breaker according to the third embodiment does not include the second bellows 14 and the sliding seal (an alternative to the second bellows 14) 50 according to the first and second embodiments, and is a three-phase vacuum. The valve 2 is insulated and supported by the insulating holder 6 in an exposed state in the atmosphere, and the supporting direction is perpendicular to the ground. That is, the movable contact 3 and the fixed contact 4 of the vacuum valve are arranged in a substantially vertical direction with respect to the ground.
A movable conductor 9 connected to the movable contact 3 of the vacuum valve 2 hermetically penetrates the first bellows 10 which can be expanded and contracted vertically downward, a first movable rod 11, an insulating rod 12 made of an insulating material, The second movable rod 13 and a contact pressure spring portion 28A including a contact pressure spring rod 27, a contact pressure spring 28, and a contact pressure spring link 29 are connected on the same axis.

  In the first bellows 10 described above, a load is generated in the direction in which the movable contact 3 is closed due to the pressure difference between the vacuum in the vacuum valve 2 and the atmospheric pressure. Conversely, a load is generated from the movable contact 3 to the contact pressure spring portion 28A in the direction in which the movable contact 3 opens due to gravity acting on its own mass. Therefore, the difference between the two loads is the self-closing force of the vacuum valve 2.

  On the other hand, an operation mechanism frame 17 exists below the vacuum circuit breaker, and a three-phase collective drive type contact opening / closing operation mechanism 18 is attached. The contact opening / closing operation mechanism 18 transmits an operating force from the output lever 20 rotating around the output shaft 19 to the three-phase vacuum valve 2 via the output link 21, the three-phase shaft lever 22, and the three-phase shaft 23. At the opening position of the vacuum circuit breaker, the output lever 20 and the output link 21 are unloaded, and similarly, a movable open spring rod 24 connected to the three-phase shaft lever 22 and an open spring receiver 25 fixed to the operation mechanism frame 17. The open spring 26 inserted in a compressed state during the period pushes the open spring rod 24 to the left (FIG. 4) by its repulsive force. The release spring rod 24 rotates the three-phase shaft 23 clockwise via the three-phase shaft lever 22 and pushes down the contact pressure spring portion 28A connected to the right side of the three-phase shaft lever 22 with the three-phase shaft 23 interposed therebetween. . The contact pressure spring 28 is a member for pressing the movable contact 3 against the fixed contact 4 with a constant contact pressure at the closing position of the vacuum circuit breaker, and is therefore unloaded at the opening position.

  The pressed contact pressure spring portion 28A transmits the repulsive force of the release spring 26 in the direction in which the movable contact 3 opens. At this time, since the transmitted repulsive force of the open spring 26 is larger than the three-phase self-closing force of the vacuum valve 2, the vacuum circuit breaker is held in the open position. The opening position is always a constant position when the three-phase shaft lever 22 comes into contact with the stopper bolt 33 fixed to the operation mechanism frame 17 and the rotation of the three-phase shaft 23 is stopped.

  In the vacuum circuit breaker according to Embodiment 3 described with reference to FIG. 4, the vacuum valve 2 is insulated and supported in the vertical direction in the atmosphere by the insulating holder 6 and is connected to the movable contact 3 of the vacuum valve 2. Passes through the first bellows 10 which can expand and contract in a vertically downward direction, and includes a first movable rod 11, an insulating rod 12 made of an insulating material, a second movable rod 13, and a contact pressure spring rod. A contact pressure spring portion 28A including a contact pressure spring 28, a contact pressure spring 28, and a contact pressure spring link 29 is connected on the same axis. This configuration can be appropriately implemented by arranging the vacuum valve 2 in the vertical direction also in the vacuum circuit breakers according to the first and second embodiments and the fourth embodiment (described later) in which the vacuum valve 2 is arranged in the horizontal direction. is there.

Next, a vacuum degree confirmation device and a vacuum degree confirmation method for a vacuum circuit breaker will be described.
The load measuring device 35 is detachably attached. At the opening position of the vacuum circuit breaker, the end portion of the operation rod 51 extending from the connection portion of the open spring rod 24 and the three-phase shaft lever 22 is the operation mechanism frame 17. And is connected to one of the load measuring devices 35 via a joint 34 that is detachable by an operation rod connecting pin 52. Connected to the opposite side of the load measuring device 35 is a pressing mechanism 36a for pushing the open spring rod 24 to the right (FIG. 4) together with the load measuring device 35. The pressing mechanism 36a is operated by a detachable measuring frame 37. It is fixed to the mechanism frame 17.

A method for confirming the degree of vacuum of the vacuum circuit breaker will be described.
After completion of the production of the vacuum circuit breaker, the load measuring device 35 is set, and the release spring rod 24 is pushed to the right together with the load measuring device 35 by the pressing mechanism 36a, thereby closing the movable contact 3 by at least 0.1 mm from the open position. The load F ₀ [N] which attempts to push the open spring rod 24 back to the left is measured by the load measuring device 35.

here,
Spring constant of the open spring 26: K _S [N / mm]
Deflection from the natural length of the open spring 26: X _S [mm]
Lever ratio from the second movable rod 13 to the open spring rod 24: L [−]
Effective cross-sectional area of the first bellows 10: S _B [mm ² ]
Atmospheric pressure (absolute pressure) around the vacuum circuit breaker: P _A [Pa]
Vacuum pressure in vacuum valve 2 (absolute pressure): P _V [Pa]
Spring constant of the first bellows 10: K _B [N / mm]
Deflection from the natural length of the first bellows 10: X _B [mm]
Total movable part mass from the movable contact 3 to the contact pressure spring part 28A: M [kg]
Gravity acceleration: G [m / s ² ]
Then, the load F ₀ [N] is expressed by the following equation (9).

_{F 0 = K S * X S} - 3 * L * {S B * (P A - P V) + K B * X B - M * G} ...... (9)

When the vacuum circuit breaker production is completed, the initial value of atmospheric pressure P ₀ [Pa] is measured using the above-described degree of vacuum confirmation device using a load F ₀ [N] and a general barometer, and when the record storage is completed, Since 34 and the measurement frame 37 are detachable, the vacuum circuit breaker is used with the vacuum degree confirmation device removed.

At the time of inspection, attach a vacuum degree confirmation device to the vacuum circuit breaker again and measure the load F ₁ [N] applied to the open spring rod. At this time, since the atmospheric pressure P ₀ [Pa] other than the expression (9) is not affected by the use conditions of the vacuum circuit breaker, it is a value determined as a design value or a manufacturing control value. If the surrounding atmospheric pressure (absolute pressure) is P _A ′ [Pa], the load F ₁ [N] is expressed by the following equation (10).

_{F 1 = K S * X S} - 3 * L * {S B * (P A '- P V) + K B * X B - M *
G} ......... (10)

Atmospheric pressure P _{A '[Pa]} is changed by the operating environment of the vacuum interrupter, since also affects self closing force of the vacuum valve 2, the atmospheric pressure P _A during _inspection' after having measured [Pa] The initial load F ₀ [N] is corrected to the load F ₀ '[N] by the following equation (11), and then compared with the load F ₁ [N] at the time of inspection.

_{F 0 '= F 0 + 3} * L * S B * (P A - P A') ...... (11)

If there is no abnormality in the vacuum degree of the vacuum valve 2, the loads F ₀ '[N] and F ₁ [N] should show the same value, but if one of the three-phase vacuum valves 2 is broken, the air-tightness of one phase is broken. When the inside of the vacuum valve 2 is completely replaced with the atmospheric pressure P _A ′ [Pa], the load F ₁ ′ [N] increases from the load F ₀ ′ [N] as expressed by the following equation (12). Therefore, it is possible to confirm a decrease in the degree of vacuum.

_{F 1 '= F 0' +} L * S B * P A '...... (12)

  In the third embodiment, the description has been given mainly based on the load measuring device 35, but the present invention can also be appropriately implemented by a torque measuring device 54 described later.

Embodiment 4 FIG.
A fourth embodiment of the present invention will be described with reference to FIG.
FIG. 5 is a plan view showing a state in which the degree-of-vacuum confirmation apparatus according to Embodiment 4 of the present invention is installed in a vacuum circuit breaker at an open position.

In FIG. 5, the vacuum circuit breaker according to the fourth embodiment has a three-phase collective drive type contact opening / closing operation mechanism and has substantially the same structure as the vacuum circuit breaker according to the first embodiment. A feature of the fourth embodiment is that torque is measured by driving a torque measuring device 54 that is detachably attached to the end of each of the end portions by a rotating mechanism 53 to confirm a decrease in the degree of vacuum.
The torque measurement device 54 and the rotation mechanism 53 are detachably attached to the operation mechanism frame 17 by a measurement frame 37.
The rotation mechanism 53 is a combination of a shaft simply connected to the torque measuring device 54 and a rotary bearing that guides this shaft in the radial direction, and measures the load by grasping and rotating the shaft. Further, since the shaft is connected to the three-phase shaft 23 via the torque measuring device 54 and the joint 34, the three-phase operation is naturally performed.
When the rotating mechanism 53 is a lever mechanism (not shown), one end of a rod-shaped lever is connected to the tip of the shaft, and the other end of the lever is operated to rotate the shaft to apply a load. taking measurement.

The second movable rod 13 penetrates the second bellows 14 attached to the base plate 5 in an airtight manner, so that the insulating gas pressurized and sealed in the sealed container 1 is retained from the outside of the sealed container 1. The movable contact 3 of the vacuum valve 2 can be opened and closed.
Similar to the vacuum circuit breaker according to the first embodiment, the first bellows 10 in the vacuum valve 2 includes
Due to the pressure difference between the vacuum and the pressure of the insulating gas pressurized and sealed in the sealed container 1, a load is generated in the direction in which the movable contact 3 is closed. The load due to the pressure difference between the vacuum and the insulating gas is the self-closing force of the vacuum valve 2. This self-closing force is generated as the rotational force of the three-phase shaft 23, and the torque measurement device 54 measures the rotational force of the three-phase shaft 23.

  The torque measuring device 54 measures the rotational torque of the three-phase shaft 23 consisting of the sum of the self-closing force for the three phases of the vacuum valve and the repulsive force of the opening spring. The initial measured value of the rotating torque is recorded and stored, and the vacuum degree of the vacuum valve 2 at the time of inspection is checked by comparing the measured value of the rotating torque with the initial measured value of the rotating torque at the time of checking the vacuum circuit breaker. Is to confirm.

  The torque measuring device 54 is constituted by a rotating mechanism 53, and rotates the three-phase shaft 23 clockwise or counterclockwise to move the vacuum circuit breaker in a direction to close the three-phase collectively, thereby rotating torque. Measure and confirm whether any vacuum drop has occurred in any of the three phases of the vacuum valve 2. The rotation mechanism 53 is constituted by a lever mechanism.

Hereinafter, the vacuum degree confirmation method of the vacuum circuit breaker implemented in each embodiment will be described.
First, the vacuum confirmation method in Embodiment 1, 2, and 3 is demonstrated.
This vacuum degree confirmation method is performed by the following seven steps.
(1) Upon completion of the manufacture of the vacuum circuit breaker, the load measuring device 35 is pulled down by the tension mechanism 36b, and the movable contact 3 is moved in the direction of closing at least 0.1 mm from the open position, and the initial measurement load generated by this movement An initial load measuring step for measuring F ₀ ;
(2) an initial atmospheric pressure measuring step for measuring the atmospheric pressure around the sealed container at the time of the initial load measuring step;
(3) An initial value storing step for recording and storing the atmospheric pressure in the atmospheric pressure measuring step and the load in the initial load measuring step as initial values;
(4) During the inspection of the vacuum circuit breaker, the inspection load measurement step for measuring the inspection measurement load F ₁ applied to the spring rod corresponding to the initial measurement load F ₀ in the same manner as the initial load measurement step;
(5) Inspection atmospheric pressure measurement step for measuring the atmospheric pressure around the sealed container during the measurement of the load measurement step during inspection,
(6) _A load correction step for correcting the initial measurement load F ₀ to the inspection load at the atmospheric pressure P _A ′ at the time of inspection, and (7) the measurement load F ₁ during the inspection of the load during the inspection when inspecting the vacuum circuit breaker. And a verification check step for confirming whether or not the vacuum valve 2 has been reduced in vacuum by checking by comparing the corrected load F ₀ ′ of the initial measured load that is corrected in accordance with the atmospheric pressure P _A ′ at the time of inspection. .

Next, the vacuum degree confirmation method in Embodiment 4 is demonstrated.
This vacuum degree confirmation method is performed by the following seven steps.
(1) An initial rotational torque measuring step for measuring rotational torque by the torque measuring device 54 when the production of the vacuum circuit breaker is completed;
(2) an initial atmospheric pressure measuring step for measuring the atmospheric pressure around the sealed container at the time of the initial rotational torque measuring step;
(3) An initial value storing step for recording and storing the atmospheric pressure by the atmospheric pressure measuring step and the rotational torque by the initial rotational torque measuring step as initial values;
(4) Inspecting rotational torque measurement step for measuring initial rotational torque when inspecting the vacuum circuit breaker,
(5) An inspection atmospheric pressure measurement step for measuring the atmospheric pressure around the sealed container at the time of the inspection rotational torque measurement step,
(6) Correction step for correcting the initial measured rotational torque to the rotational torque at the time of inspection at the atmospheric pressure at the time of inspection, and (7) At the time of inspection of the vacuum circuit breaker, the rotational torque measured at the time of inspection and the rotational torque measured at the time of inspection A collation confirmation step for confirming whether or not the vacuum degree of the vacuum valve 2 is lowered at the time of inspection by comparing and collating with the corrected rotational torque of the initial measured rotational torque corrected according to the atmospheric pressure.

Next, a specific example 1 of the vacuum circuit breaker confirmation method performed by the load measuring device 35 or the torque measuring device 54 will be described.
In the vacuum level confirmation method according to claim 15, when the self-closing force of the vacuum valve 2 decreases due to a decrease in the vacuum level of any of the three phases, the sum of the repulsive force of the opening spring 26 changes and the vacuum valve 2 is checked. Since either the load or the rotational torque at the time increases from the initial value, it is detected and it is confirmed whether the degree of vacuum has occurred in any of the three phases of the vacuum valve 2.

Next, the specific example 2 of the vacuum degree confirmation method of the vacuum circuit breaker implemented by the load measuring device 35 or the torque measuring device 54 will be described.
In the vacuum degree confirmation method according to claim 16, the vacuum valve 2 is installed in an insulating gas pressurized and sealed in a sealed container, and the movable rod of the vacuum circuit breaker maintains gas tightness in the sealed container. The movable rod penetrates from the sealed container to the outside through the bellows, and the movable rod has a force in a direction in which the movable contact is separated from the fixed contact by the pressure difference between the atmospheric pressure around the sealed container and the insulating gas, and the vacuum valve 2 Autistic forces act simultaneously, but some of the mutual forces cancel each other, and the total fluctuates with changes in atmospheric pressure, so the initial load or rotational torque is adjusted to the ambient atmospheric pressure at the time of inspection. By correcting the value, an increase from the initial value is detected, and it is confirmed whether a decrease in the degree of vacuum has occurred in any of the three phases of the vacuum valve 2.

Next, specific example 3 of the vacuum degree confirmation method for the vacuum circuit breaker implemented by the load measuring device 35 or the torque measuring device 54 will be described.
In the method for confirming the degree of vacuum related to claim 17, the vacuum valve 2 is installed in the atmospheric pressure, and the self-closing force of the vacuum valve 2 fluctuates with a change in the atmospheric pressure. By correcting the initial value of the load or the rotational torque in accordance with the atmospheric pressure, an increase from the initial value is detected, and it is confirmed whether a decrease in the degree of vacuum has occurred in any of the three phases of the vacuum valve 2.

Next, a specific example 4 of the vacuum circuit breaker confirmation method performed by the torque measuring device 54 will be described.
In the method for confirming the degree of vacuum related to claim 18, the torque measuring device 54 for measuring the rotational torque comprising the sum of the repulsive force of the open spring 26 and the self-closing force of the vacuum valve 2 rotates the vacuum circuit breaker during inspection. The degree of vacuum of the vacuum valve 2 is detected and confirmed by measuring the torque.

Next, a specific example 5 of the vacuum circuit breaker confirmation method performed by the torque measuring device 54 will be described.
In the vacuum degree confirmation method according to claim 19, the initial value of the rotational torque is recorded at the completion of the manufacture of the vacuum circuit breaker, and the measured value of the rotational torque at the time of inspection is compared with the initial torque value, whereby the vacuum valve 2. Check whether any of the three phases of 2 have a reduced vacuum.

Furthermore, a specific example 6 of the vacuum circuit breaker vacuum degree checking method implemented by the torque measuring device 54 will be described.
In the degree-of-vacuum confirmation method according to claim 20, the rotation mechanism 53 of the torque measuring device 54 rotates the three-phase shaft 23 clockwise or counterclockwise to close the vacuum valve 2 in three phases at once. , The rotational torque is measured, and it is confirmed whether any of the three phases of the vacuum valve 2 has a reduced degree of vacuum.

In the first to fourth embodiments, a three-phase vacuum circuit breaker using three vacuum valves 2 has been described as an example, but a single-phase vacuum circuit breaker using one vacuum valve 2 is used. Even in the case of the vessel, the same effects as those of the first to fourth embodiments can be obtained in the object of the present invention to surely confirm the decrease in the degree of vacuum.

  It should be noted that the present invention can be combined with each other within the scope of the invention, and each embodiment can be modified or omitted as appropriate.

1: sealed container, 2: vacuum valve, 3: movable contact, 4: fixed contact,
10: 1st bellows, 11: 1st movable rod,
12: Insulating rod, 13: Second movable rod, 14: Second bellows,
17: Operation mechanism frame, 18: Three-phase batch drive type contact opening / closing operation mechanism,
19: output shaft, 20: output lever, 21: output link, 22: three-phase shaft lever,
23: Three-phase shaft, 24: Open spring rod, 25: Open spring receiver, 26: Open spring,
27: Contact pressure spring rod, 28: Contact pressure spring, 29: Contact pressure spring link,
28A: contact pressure spring part, 35: load measuring device, 36a: pressing mechanism,
36b: tension mechanism, 37: measurement frame, 53: rotation mechanism,
54: Torque measuring device

Claims (20)

A vacuum valve having a movable contact and a fixed contact, housed in a sealed container filled with an insulating gas, a contact opening / closing operation mechanism for opening / closing the movable contact and the fixed contact, and the contact opening / closing operation mechanism, Confirming the degree of vacuum of a vacuum circuit breaker equipped with a load measuring device for measuring a load consisting of the sum of the repulsive force of an open spring that urges the movable contact in the direction of separating from the fixed contact and the self-closing force of the vacuum valve A device,
The load measuring device is detachably attached to the contact opening / closing operation mechanism, and records and saves the atmospheric pressure P _{0 and} the initial measured load F _{0 at the} atmospheric pressure P ₀ when the manufacture of the vacuum circuit breaker is completed. When checking the vacuum circuit breaker, by comparing and comparing the measured load F ₁ at the time of inspection with the corrected load F ₀ ′ of the initial measured load corrected according to the atmospheric pressure P _A ′ at the time of inspection A vacuum degree confirmation device for a vacuum circuit breaker, comprising confirmation means for confirming a degree of vacuum of the vacuum valve at the time of inspection. Sealed container with insulating gas sealed,
A vacuum valve housed in the sealed container and having a movable contact and a fixed contact;
A contact opening / closing operation mechanism for opening / closing the movable contact and the fixed contact via a movable rod and a movable conductor;
A first bellows for maintaining the vacuum tightness of the movable conductor with respect to the vacuum valve;
A second bellows for keeping the movable rod airtight with respect to the sealed container;
An open spring provided in the contact opening / closing operation mechanism and biasing the movable contact in a direction separating the fixed contact from the fixed contact by a repulsive force, and a sum of a repulsive force of the open spring and a self-closing force of the vacuum valve A load measuring device for measuring the load consisting of
The first bellows and the second bellows have the same effective cross-sectional area in which loads are offset against each other,
The load measuring device is detachably attached to the contact opening / closing operation mechanism,
When the production of the vacuum circuit breaker is completed, the atmospheric pressure P ₀ and the initial measurement load F _{0 of the} load at the atmospheric pressure P ₀ are recorded and stored.
In addition, when checking the vacuum circuit breaker, by comparing and comparing the measured load F ₁ at the time of inspection with the corrected load F ₀ ′ of the initial measured load corrected according to the atmospheric pressure P _A ′ at the time of inspection. A vacuum degree confirmation device for a vacuum circuit breaker, comprising confirmation means for confirming a degree of vacuum of the vacuum valve at the time of inspection. Sealed container with insulating gas sealed,
A vacuum valve housed in the sealed container and having a movable contact and a fixed contact;
A contact opening / closing operation mechanism for opening / closing the movable contact and the fixed contact via a movable rod and a movable conductor;
A first bellows for maintaining the vacuum tightness of the movable conductor with respect to the vacuum valve;
A sliding seal that holds the airtightness of the movable rod with respect to the sealed container and is an alternative part of the second bellows;
An open spring provided in the contact opening / closing operation mechanism and biasing the movable contact in a direction separating the fixed contact from the fixed contact by a repulsive force, and a sum of a repulsive force of the open spring and a self-closing force of the vacuum valve A load measuring device for measuring the load consisting of
The load measuring device is detachably attached to the contact opening / closing operation mechanism,
When the production of the vacuum circuit breaker is completed, the insulating gas pressure Pg of the sealed container and the initial measurement load F _{0 at the} insulating gas pressure Pg are recorded and stored.
In addition, when checking the vacuum circuit breaker, the comparison load of the measured load F ₁ at the time of inspection and the corrected load F ₀ ′ of the initial measured load corrected according to the insulating gas pressure Pg ′ at the time of inspection is compared. A vacuum degree confirmation device for a vacuum circuit breaker, comprising: confirmation means for confirming the degree of vacuum of the vacuum valve at the time of inspection. A vacuum valve arranged in the atmosphere with a movable contact and a fixed contact,
A contact opening / closing operation mechanism for opening / closing the movable contact and the fixed contact via a movable rod and a movable conductor;
A first bellows for maintaining the vacuum tightness of the movable conductor with respect to the vacuum valve;
An open spring provided in the contact opening / closing operation mechanism and biasing the movable contact in a direction separating the fixed contact from the fixed contact by a repulsive force, and a sum of a repulsive force of the open spring and a self-closing force of the vacuum valve A load measuring device for measuring the load consisting of
The load measuring device is detachably attached to the contact opening / closing operation mechanism,
When the production of the vacuum circuit breaker is completed, the atmospheric pressure P ₀ and the initial measurement load F _{0 at the} atmospheric pressure P ₀ are recorded and stored.
In addition, when checking the vacuum circuit breaker, by comparing and comparing the measured load F ₁ at the time of inspection with the corrected load F ₀ ′ of the initial measured load corrected according to the atmospheric pressure P _A ′ at the time of inspection. A vacuum degree confirmation device for a vacuum circuit breaker, comprising confirmation means for confirming a degree of vacuum of the vacuum valve at the time of inspection.   The said load measuring device is comprised by the torque measuring device which is an alternative device, The vacuum degree confirmation apparatus of the vacuum circuit breaker of any one of Claim 1 to 4 characterized by the above-mentioned.   6. The vacuum circuit breaker vacuum degree confirmation device according to claim 1, wherein the movable contact and the fixed contact of the vacuum valve are arranged in a direction perpendicular to the ground.   The said contact opening / closing operation mechanism is comprised by the contact opening / closing operation mechanism of a three-phase collective drive type, The vacuum degree confirmation apparatus of the vacuum circuit breaker of any one of Claim 1 to 6 characterized by the above-mentioned. .   The load measuring device is configured by a pressing or pulling mechanism, and the pressing valve or the pulling mechanism moves the vacuum valve in a direction to close the three-phase collectively, thereby measuring the load and either of the three phases of the vacuum valve. The vacuum degree confirmation device for a vacuum circuit breaker according to claim 7, wherein it is confirmed whether or not a reduction in vacuum degree has occurred.   The vacuum checking device for a vacuum circuit breaker according to claim 8, wherein the pressing or pulling mechanism is constituted by a screw mechanism.   The vacuum checking device for a vacuum circuit breaker according to claim 8, wherein the pressing or pulling mechanism is constituted by a lever mechanism.   The torque measuring device is constituted by a rotating mechanism, and the rotating mechanism moves the vacuum valve in the direction of closing the three-phase at once, thereby measuring the rotational torque and applying a vacuum degree to one of the three phases of the vacuum valve. 8. The vacuum degree confirmation device for a vacuum circuit breaker according to claim 7, wherein it is confirmed whether or not a drop has occurred.   The vacuum degree confirmation device for a vacuum circuit breaker according to claim 11, wherein the rotation mechanism is configured by a lever mechanism. A method for confirming a degree of vacuum performed by the vacuum circuit breaker according to any one of claims 1, 2, 3, and 4,
(1) Upon completion of the production of the vacuum circuit breaker, the load measuring device is pulled down by the tension mechanism, and the movable contact 3 is moved in the direction of closing at least 0.1 mm from the open position, and the initial measurement load F ₀ generated by this movement is obtained. Measuring initial load measuring step,
(2) an initial atmospheric pressure measuring step for measuring the atmospheric pressure around the sealed container at the time of the initial load measuring step;
(3) an initial value storing step for recording and storing the atmospheric pressure in the atmospheric pressure measuring step and the load in the initial load measuring step as initial values;
(4) An inspection load measurement step for measuring the inspection measurement load F ₁ applied to the spring rod corresponding to the initial measurement load F ₀ in the same manner as the initial load measurement step when the vacuum circuit breaker is inspected, (5) Atmospheric pressure measurement step during inspection to measure the atmospheric pressure around the sealed container at the time of the load measurement step during inspection,
(6) the initial measuring load F _0, the load correction step for correcting the inspection under load at atmospheric pressure P _{A 'when} inspected, and (7) when inspection of the vacuum circuit breaker, inspection during the measurement of the load at the time of inspection By comparing and comparing the load F ₁ and the correction load F ₀ ′ of the initial measurement load corrected in accordance with the atmospheric pressure P _A ′ at the time of inspection, whether or not the vacuum degree of the vacuum valve 2 is reduced at the time of inspection is determined. A method for confirming the degree of vacuum of a vacuum circuit breaker including a verification confirmation step for confirmation.   The method for confirming the degree of vacuum of a vacuum circuit breaker according to claim 13, wherein the load measuring device is constituted by a torque measuring device which is an alternative device. It is a vacuum confirmation method implemented with the vacuum circuit breaker according to claim 7,
When the self-closing force of one of the three phases decreases due to a decrease in the degree of vacuum, the sum of the repulsive force of the open spring changes, and either the load or rotational torque during inspection is greater than the initial value. A method for confirming the degree of vacuum of a vacuum circuit breaker, wherein the degree of vacuum is detected and whether or not a decrease in degree of vacuum has occurred in any of the three phases of the vacuum valve is confirmed. It is a vacuum confirmation method implemented with the vacuum circuit breaker according to claim 7,
The vacuum valve is installed in insulating gas pressurized and sealed in a sealed container, and the movable rod of the vacuum circuit breaker penetrates from the sealed container to the outside via a bellows to maintain gas tightness in the sealed container. The movable rod is simultaneously subjected to the force in the direction of separating the movable contact from the fixed contact due to the pressure difference between the atmospheric pressure around the sealed container and the insulating gas, and the self-closing force of the vacuum valve. Is partially offset, and the total fluctuates with changes in atmospheric pressure. Therefore, by correcting the initial value of the load or rotational torque according to the ambient atmospheric pressure at the time of inspection, the increase from the initial value can be achieved. The vacuum degree check method for the vacuum circuit breaker is characterized by detecting whether or not a decrease in the vacuum degree has occurred in any of the three phases of the vacuum valve. It is a vacuum confirmation method implemented with the vacuum circuit breaker according to claim 7,
The vacuum valve is installed in atmospheric pressure, and the self-closing force of the vacuum valve fluctuates with changes in atmospheric pressure, so the initial value of load or rotational torque is adjusted according to the ambient atmospheric pressure at the time of inspection. A method for confirming the degree of vacuum of a vacuum circuit breaker, wherein an increase from an initial value is detected by correction and whether or not a decrease in degree of vacuum has occurred in any of the three phases of the vacuum valve is confirmed. A method for confirming the degree of vacuum performed by the vacuum circuit breaker according to claim 5,
When the vacuum circuit breaker is inspected, the degree of vacuum of the vacuum valve is detected and checked by a torque measuring device that measures the rotational torque consisting of the sum of the repulsive force of the open spring and the self-closing force of the vacuum valve. A method for confirming the degree of vacuum of a vacuum circuit breaker. A method for confirming the degree of vacuum performed by the vacuum circuit breaker according to claim 5,
By using a torque measurement device, record the initial value of the rotational torque when the vacuum circuit breaker is completed, and compare the measured value of the rotational torque with the initial torque value at the time of inspection. A method for confirming the degree of vacuum of a vacuum circuit breaker, characterized by confirming whether or not a degree of vacuum has been reduced. A method for confirming the degree of vacuum performed by the vacuum circuit breaker according to claim 5,
By rotating the three-phase shaft clockwise or counterclockwise with the rotation mechanism of the torque measuring device and moving the vacuum valve in the direction of closing the three-phase collectively, the rotational torque is measured, and the vacuum valve A method for confirming the degree of vacuum of a vacuum circuit breaker, characterized in that it is confirmed whether or not a decrease in degree of vacuum has occurred in any of the three phases.

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