On-load tap changer

Abstract

The on-load tap changer (100) comprises an input shaft (O1), an output shaft (O2), an input crank portion (1), a connecting rod portion (2), a swing crank portion (3), a first spring (6a), a second spring (6b), an output crank portion (4), a first limiting member (5a) and a second limiting member (5b), and an on switch (10). The swing crank portion (3) comprises a swing side first portion (31) and a swing side second portion (32). The swing side second portion (32) and the swing side first portion (31) sandwich the output shaft (O2). The first spring (6a) is connected with the swing side first portion (31). The second spring (6b) is connected with the swing side second portion (32). The direction of the force acting on the swing side second portion (32) under the action of the second spring (6b) is opposite to the direction of the force acting on the swing side first portion (31) under the action of the first spring (6a).

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a load tap changer. BACKGROUND

[0002] At present, there is a load tap changer that changes a tap of a transformer. The load tap changer changes the tap of a tap winding in a state where a voltage is applied to the tap winding, thereby adjusting the voltage applied to the tap winding. For example, the load tap changer described in Japanese Patent Application Publication No. 54-9720 includes an input shaft, a crank (input crank portion), a support shaft (output shaft), a swing lever (swing crank portion), a bypass interrupter (on-off switch), a connecting rod (link portion), a change lever (output crank portion), and a tension spring (first spring). The input shaft is driven by a driving source. The crank is fixed to the input shaft. The swing lever is fixed to the shaft. The bypass interrupter is connected to the swing lever and the shaft. The first end portion of the connecting rod is connected to the swing lever by a hinged connection. The second end portion of the connecting rod is connected to the crank by a hinged connection. Due to the rotation of the swing lever, the tension spring is stretched to store energy. The change lever is actuated by the energy of the tension spring that is released. When the change lever is actuated, the force (spring force) generated by the energy of the tension spring acts in the radial direction of the change lever.

[0003] Patent Document 1: Japanese Patent Application Publication No. 54-9720 SUMMARY

[0004] The present disclosure was made in view of the above-described technical problem, and an object thereof is to provide a load tap changer that can suppress vibration of a swing crank portion.

[0005] In the load tap changer described in the above-described publication, the force of the first spring (tension spring) acts not only on the output crank portion (change lever) but also on the swing crank portion (swing lever) in the radial direction of the shaft of the swing crank portion. Therefore, the swing crank portion vibrates.

[0006] The on-load tap changer of the present disclosure includes an input shaft, an output shaft, an input crank portion, a link portion, a swing crank portion, a first spring, a second spring, an output crank portion, first and second stoppers, and an on-off switch. The input shaft is rotatable. The output shaft is disposed separately from the input shaft. The input shaft is coupled to the input crank portion. The link portion is coupled to the input crank portion at a position different from the position at which the input shaft is coupled to the input crank portion. The link portion is coupled to the swing crank portion. The swing crank portion is rotatable about the output shaft. The swing crank portion includes a swing-side first portion and a swing-side second portion. The swing-side second portion sandwiches the output shaft with the swing-side first portion. The first spring is coupled to the swing-side first portion. The second spring is coupled to the swing-side second portion. The output crank portion includes an output-side first portion and an output-side second portion. The first spring is coupled to the output-side first portion. The output-side second portion sandwiches the output shaft with the output-side first portion. The second spring is coupled to the output-side second portion. The output crank portion is rotatable about the output shaft. The first and second stoppers are contactable with the output-side second portion. The on-off switch is coupled to the swing crank portion. The on-off switch includes a plurality of contacts and a switching portion. The switching portion is contactable with the plurality of contacts. Rotation of the input shaft is transmitted by the input crank portion and the link portion, so that the swing crank portion is rotatable. Rotation of the swing crank portion is transmitted to the output crank portion by the first and second springs, so that the output-side second portion is rotatable in contact with either of the first and second stoppers. The on-off switch is capable of switching the plurality of contacts in contact with the switching portion by rotation of the swing crank portion. The direction of the force acting on the swing-side second portion by the second spring is opposite to the direction of the force acting on the swing-side first portion by the first spring.

[0007] According to the on-load tap changer of the present disclosure, the direction of the force acting on the swing-side second portion by the second spring is opposite to the direction of the force acting on the swing-side first portion by the first spring. Therefore, the force acting on the swing crank portion by the first spring and the force acting on the swing crank portion by the second spring cancel each other out. Thus, vibration of the swing crank portion can be suppressed.

[0008] The above and other objects, features, aspects and advantages of the present disclosure will become more apparent from the following detailed description of the disclosure when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 is a plan view schematically showing the structure of the on-load tap changer of Embodiment 1.

[0010] Figure 2 is a side view schematically showing the structure of the on-load tap changer of Embodiment 1.

[0011] Figure 3is a plan view schematically showing a state in which the switching section of the on-load tap changer of Embodiment 1 is separated from the second contact point.

[0012] Figure 4 is a plan view schematically showing a state in which the switching section of the on-load tap changer of Embodiment 1 is in contact with the first contact point.

[0013] Figure 5 is a plan view schematically showing a state in which the output crank section of the on-load tap changer of Embodiment 1 is in contact with the first stopper.

[0014] Figure 6 is a circuit diagram schematically showing a state in which the switching section of the on-load tap changer of Embodiment 1 is in contact with the second contact point and the B-side energizing switch is energized.

[0015] Figure 7 is a circuit diagram schematically showing a state in which the switching section of the on-load tap changer of Embodiment 1 is separated from the second contact point and the B-side energizing switch is energized.

[0016] Figure 8 is a circuit diagram schematically showing a state in which the switching section of the on-load tap changer of Embodiment 1 is in contact with the first contact point and the B-side energizing switch is energized.

[0017] Figure 9 is a circuit diagram schematically showing a state in which the switching section of the on-load tap changer of Embodiment 1 is in contact with the first contact point and the B-side energizing switch and the R-side energizing switch are energized.

[0018] Figure 10 is a circuit diagram schematically showing a state in which the switching section of the on-load tap changer of Embodiment 1 is in contact with the first contact point and the R-side energizing switch is energized.

[0019] Figure 11 is a circuit diagram schematically showing a state in which the switching section of the on-load tap changer of Embodiment 1 is in contact with the first contact point and the A-side energizing switch and the R-side energizing switch are energized.

[0020] Figure 12 is a circuit diagram schematically showing a state in which the switching section of the on-load tap changer of Embodiment 1 is in contact with the first contact point and the A-side energizing switch is energized.

[0021] Figure 13 is a chart schematically showing a connection state of the on-off switch and the energizing switch switching mechanism of the on-load tap changer of Embodiment 1.

[0022] Figure 14 is a plan view schematically showing a structure of the on-load tap changer of Embodiment 2.

[0023] Figure 15 is Figure 14 an enlarged view of the XX-XX region of FIG. 1.

[0024] Figure 16 is a plan view schematically showing the structure of the on-load tap changer of Embodiment Three.

[0025] Figure 17 is a plan view schematically showing the structure of the latch of the on-load tap changer of Embodiment Three.

[0026] Figure 18 is a side view schematically showing the structure of the on-load tap changer of Embodiment Three.

[0027] Figure 19 is a plan view schematically showing the state in which the switching section of the on-load tap changer of Embodiment Three is separated from the U-phase second contact, the V-phase second contact, and the W-phase second contact.

[0028] Figure 20 is a plan view schematically showing the state in which the switching section of the on-load tap changer of Embodiment Three is in contact with the U-phase first contact, the V-phase first contact, and the W-phase first contact and the output crank section is locked to the first latch section.

[0029] Figure 21 is a plan view schematically showing the state in which the switching section of the on-load tap changer of Embodiment Three is in contact with the U-phase first contact, the V-phase first contact, and the W-phase first contact and the output crank section is locked to the second latch section. DETAILED DESCRIPTION

[0030] Embodiment 1

[0031] using Figures 1-5 The structure of the on-load tap changer 100 of Embodiment One will be described. As shown in FIG. 1, the on-load tap changer 100 includes an input shaft O1, an output shaft O2, an input crank section 1, a connecting rod section 2, a swing crank section 3, an output crank section 4, a first stopper 5a and a second stopper 5b, a first spring 6a, a second spring 6b, a connecting section 9, an on-off switch 10, and a conduction switch switching mechanism not shown. Figure 1 The input shaft O1 is rotatable. The input shaft O1 is self-rotatable. The input shaft O1 is rotated by a driving source not shown such as a motor. In this embodiment, the input shaft O1 is rotated in the counterclockwise direction. In addition, although not shown, the input shaft O1 can also be rotated in the clockwise direction.

[0032] The output shaft O2 is disposed separately from the input shaft O1. The output shaft O2 supports the swing crank section 3 and the output crank section 4 so as to be freely rotatable.

[0033] ​

[0034] An input shaft O1 is coupled to the input crank portion 1. The input shaft O1 is fixed to the input crank portion 1. Desirably, the input shaft O1 is fixed to the center of the input crank portion 1. The input crank portion 1 is rotatable about the input shaft O1 by the rotation of the input shaft O1.

[0035] The link portion 2 is coupled to the input crank portion 1 at a position different from the position at which the input shaft O1 is coupled to the input crank portion 1. Thus, the input shaft O1, the input crank portion 1, and the link portion 2 constitute a crank. The link portion 2 is coupled to the input crank portion 1 at a position away from the center of the input crank portion 1. Further, the link portion 2 is coupled to the input crank portion 1 at a position away from the position at which the input shaft O1 is coupled to the input crank portion 1. Thus, the link portion 2 is rotatable about the input shaft O1 by the rotation of the input shaft O1. Further, the link portion 2 is coupled to the input crank portion 1 so as to be rotatable freely. Thus, the link portion 2 is rotatable relative to the input crank portion 1 by the rotation of the input shaft O1.

[0036] The swing crank portion 3 is rotatable about the output shaft O2. The link portion 2 is coupled to the swing crank portion 3. The link portion 2 is coupled to the swing crank portion 3 at a position different from the position at which the output shaft O2 is coupled to the swing crank portion 3. Thus, the output shaft O2, the link portion 2, and the swing crank portion 3 constitute a crank. The swing crank portion 3 is coupled to the link portion 2 so as to be rotatable freely. The swing crank portion 3 is coupled to the input crank portion 1 via the link portion 2. The rotation of the input shaft O1 is transmitted by the input crank portion 1 and the link portion 2, so that the swing crank portion 3 is rotatable.

[0037] The swing crank portion 3 includes a swing-side first portion 31 and a swing-side second portion 32. The swing-side second portion 32 sandwiches the output shaft O2 with the swing-side first portion 31. In the present embodiment, the link portion 2 is coupled so as to be rotatable freely at the swing-side second portion 32.

[0038] The output crank portion 4 is rotatable about the output shaft O2. Thus, the output shaft O2 is a common rotation center of the swing crank portion 3 and the output crank portion 4. The output crank portion 4 is disposed so as to be superimposed on the swing crank portion 3. The output crank portion 4 sandwiches the swing crank portion 3 with the link portion 2.

[0039] The output crank portion 4 is coupled to the swing crank portion 3 by a first spring 6a and a second spring 6b. Thus, the output crank portion 4 is rotatable by the rotation of the swing crank portion 3. That is, the output crank portion 4 rotates in conjunction with the swing crank portion 3. In addition, as described later, the range in which the output crank portion 4 is rotatable is limited by a first stopper 5a and a second stopper 5b.

[0040] The output crank portion 4 includes an output side first portion 41 and an output side second portion 42. The output side second portion 42 is sandwiched by the output side first portion 41 and the output shaft O2.

[0041] The first stopper 5a and the second stopper 5b are capable of contacting the output side second portion 42. The first stopper 5a and the second stopper 5b are arranged apart from each other with a space. It is desirable that the first stopper 5a and the second stopper 5b are arranged on concentric circles with the output shaft O2 as the center. The output side second portion 42 is interposed between the first stopper 5a and the second stopper 5b. The output side second portion 42 is capable of rotating by less than 90 degrees between the first stopper 5a and the second stopper 5b. The first stopper 5a and the second stopper 5b are arranged not to contact the swing crank portion 3.

[0042] The first spring 6a and the second spring 6b are so-called energy accumulating springs configured to store elastic energy by stretching and contracting in the length direction. The first spring 6a and the second spring 6b link the swing crank portion 3 and the output crank portion 4. Therefore, the rotation of the swing crank portion 3 is transmitted by the first spring 6a and the second spring 6b, and thus the output side second portion 42 of the output crank portion 4 is capable of rotating in a manner to contact the first stopper 5a and the second stopper 5b.

[0043] The first spring 6a links the swing side first portion 31 and the output side first portion 41. The first spring 6a is linked to the swing side first portion 31. The first spring 6a is linked to the output side first portion 41. That is, the first spring 6a is linked to the output side first portion 41.

[0044] The second spring 6b links the swing side second portion 32 and the output side second portion 42. The second spring 6b is linked to the swing side second portion 32. Therefore, the position at which the second spring 6b is linked to the swing crank portion 3 is located on the opposite side to the position at which the first spring 6a is linked to the swing crank portion 3 in the length direction of the swing crank portion 3 and with respect to the output shaft O2. Therefore, the direction of the force acting on the swing side second portion 32 by the second spring 6b is opposite to the direction of the force acting on the swing side first portion 31 by the first spring 6a. The second spring 6b is linked to the output side second portion 42. That is, the second spring 6b is linked to the output side second portion 42. Therefore, the position at which the second spring 6b is linked to the output crank portion 4 is located on the opposite side to the position at which the first spring 6a is linked to the output crank portion 4 in the length direction of the output crank portion 4 and with respect to the output shaft O2. Therefore, the direction of the force acting on the output side second portion 42 by the second spring 6b is opposite to the direction of the force acting on the output side first portion 41 by the first spring 6a.

[0045] In addition, in a state where the output-side second portion 42 is in contact with any one of the first stopper 5a and the second stopper 5b, the first spring 6a and the second spring 6b are stretched compared to a normal state. Thus, the first spring 6a and the second spring 6b are energized. Thus, at the swing-side first portion 31, an acting force acts under the action of the first spring 6a. Further, at the swing-side second portion 32, an acting force acts under the action of the second spring 6b.

[0046] It is desirable that the length of the first spring 6a is equal to the length of the second spring 6b. Specifically, in a state where the first spring 6a and the second spring 6b are not stretched or contracted (normal state), the length of the first spring 6a is equal to the length of the second spring 6b. Further, in a state where the first spring 6a and the second spring 6b are stretched or contracted compared to the normal state, the length of the first spring 6a is equal to the length of the second spring 6b. Further, it is desirable that the spring coefficient of the first spring 6a is equal to the spring coefficient of the second spring 6b.

[0047] Further, it is desirable that the length in the length direction of the swing crank portion 3 from the output shaft O2 to the position at which the first spring 6a is connected to the swing-side first portion 31 is equal to the length in the length direction of the swing crank portion 3 from the output shaft O2 to the position at which the second spring 6b is connected to the swing-side second portion 32. That is, the position at which the second spring 6b is connected to the swing crank portion 3 is symmetrical to the position at which the first spring 6a is connected to the swing crank portion 3 in the length direction of the swing crank portion 3 and with respect to the output shaft O2.

[0048] Further, it is desirable that the length in the length direction of the output crank portion 4 from the output shaft O2 to the position at which the first spring 6a is connected to the output-side second portion 42 is equal to the length in the length direction of the output crank portion 4 from the output shaft O2 to the position at which the second spring 6b is connected to the output-side second portion 42. That is, the position at which the second spring 6b is connected to the output crank portion 4 is symmetrical to the position at which the first spring 6a is connected to the output crank portion 4 in the length direction of the output crank portion 4 and with respect to the output shaft O2.

[0049] Further, it is desirable that the first spring 6a and the second spring 6b are disposed symmetrically with the output shaft O2 as a center point in a plan view. The first spring 6a and the second spring 6b have shapes that are symmetrical with the output shaft O2 as a center point in a plan view.

[0050] The connecting portion 9 connects the swing crank portion 3 and the on-off switch 10. Thus, the switching portion S2 can rotate in conjunction with the rotation of the swing crank portion 3.

[0051] The on switch 10 is linked to the swing crank portion 3. The on switch 10 is, for example, an advance on switch. The on switch 10 includes a switching shaft O3, a plurality of contact points S1, and a switching portion S2.

[0052] The switching shaft O3 is linked to the linking portion 9. The switching shaft O3 is rotatable in conjunction with the rotation of the swing crank portion 3. It is desirable that the amount of rotation of the switching shaft O3 is the same as the amount of rotation of the swing crank portion 3.

[0053] The switching portion S2 is contactable with the plurality of contact points S1. The switching portion S2 is rotatable about the switching shaft O3. It is desirable that the angle of the angle formed by the switching portion S2 and the linking portion 9 is the same as the angle of the angle formed by the swing crank portion 3 and the linking portion 9. The on switch 10 is capable of switching the plurality of contact points S1 in contact with the switching portion S2 by the rotation of the swing crank portion 3.

[0054] In the present embodiment, the plurality of contact points S1 has a first contact point S11 and a second contact point S12. The switching portion S2 is contactable with either of the first contact point S11 and the second contact point S12. The on switch 10 is capable of switching either of the first contact point S11 and the second contact point S12 in contact with the switching portion S2 by the rotation of the swing crank portion 3.

[0055] The energization switch switching mechanism, which is not shown, is linked to the output crank portion 4. The energization circuit of the energization switch switching mechanism is switched to either of the even side and the odd side according to the rotation of the output crank portion 4. In the present embodiment, the energization switch mechanism switches the energization circuit to either of the state of the even side and the state of the odd side according to the contact of the output crank portion 4 with either of the first stopper 5a and the second stopper 5b. In addition, in the present embodiment, the state of the even side refers to the state of the even side tap energization described later. Further, the state of the odd side refers to the state of the odd side tap energization described later.

[0056] As shown in FIG. 1, Figure 2 In the present embodiment, the link portion 2, the swing crank portion 3, the output crank portion 4, the first spring 6a, and the second spring 6b are sequentially stacked. In addition, Figure 2 is a view of the output shaft O2 side with respect to the input shaft O1 Figure 1The image shows a side view of the on-load tap converter 100. When viewed from the side, the front ends of the first limiting member 5a and the second limiting member 5b overlap with the bottom of the output crank portion 4. Either the first limiting member 5a or the second limiting member 5b can contact the output crank portion 4 by rotating the output crank portion 4 from the front side of the paper towards the inside of the paper or from the inside of the paper towards the front side of the paper. When viewed from the side, the front ends of the first limiting member 5a and the second limiting member 5b are configured to be offset from the bottom of the swing crank portion 3. Therefore, the first limiting member 5a and the second limiting member 5b are configured not to contact the swing crank portion 3. When viewed from the side, the first spring 6a and the second spring 6b are configured to be offset from each other. Therefore, the first spring 6a and the second spring 6b do not contact each other when the swing crank portion 3 rotates. Furthermore, for ease of explanation, Figure 2 Switch 10 is not shown in the figure.

[0057] Next, use Figure 1 as well as Figures 3-5 The operation of the on-load tap converter 100 according to Embodiment 1 will be explained. Additionally, in Figure 1 as well as Figures 3-5 The operation of the on-load tap converter 100 when the input shaft O1 rotates counterclockwise will be explained. However, the input shaft O1 can also rotate clockwise.

[0058] exist Figure 1 In this state, the output crank 4 contacts the first limiting member 5a. Therefore, the counterclockwise rotation of the output crank 4 is suppressed. Furthermore, the switching part S2 of the switch 10 contacts the second contact S12. Additionally, the energizing switch switching mechanism (not shown) is in the even-numbered side state. The circuit structure and operation of the switch 10 and the energizing switch switching mechanism will be described later. In this embodiment, the state in which the output crank 4 contacts the first limiting member 5a and the switching part S2 contacts the second contact S12 is referred to as the even-numbered measurement state.

[0059] First, such as Figure 1 as well as Figure 3 As shown, the input shaft O1 begins to rotate counterclockwise. Due to the rotation of the input shaft O1, the input crank 1 rotates counterclockwise. Since the input crank 1 and the oscillating crank 3 are connected by the connecting rod 2, the oscillating crank 3 rotates counterclockwise under the action of the rotation of the input crank 1. The output crank 4 does not rotate because it is in contact with the first limiting member 5a. Therefore, the first spring 6a and the second spring 6b are stretched by the oscillating crank 3. Therefore, the elastic energy of the first spring 6a and the second spring 6b increases. That is, the first spring 6a and the second spring 6b are stored in energy.

[0060] Furthermore, since the oscillating crank portion 3 is linked to the switch 10, the switching portion S2 of the switch 10 rotates counterclockwise under the action of the rotation of the oscillating crank portion 3. Therefore, the switching portion S2 separates from the second contact S12.

[0061] Next, as Figure 4 As shown, the input shaft O1 rotates further counterclockwise. Consequently, the length direction of the oscillating crank portion 3 becomes parallel to the length direction of the output crank portion 4. Furthermore, the switching portion S2 of the switch 10 rotates further counterclockwise, contacting the first contact S11. Additionally, in Figure 4 When the conversion part S2 is in contact with the first contact S11, the output crank part 4 is in contact with the first limiting member 5a.

[0062] Next, as Figure 5 As shown, the input shaft O1 rotates further counterclockwise. Consequently, the oscillating crank portion 3 crosses the output crank portion 4 and rotates counterclockwise. That is, the oscillating crank portion 3 rotates beyond a state where its length direction is parallel to the length direction of the output crank portion 4.

[0063] When the oscillating crank 3 crosses the output crank 4, the elastic energy of the first spring 6a and the second spring 6b is released. As a result, the output crank 4 rotates clockwise. The output crank 4 rotates in a manner separating from the first limiting member 5a. The output crank 4 rotates until it contacts the second limiting member 5b. The rotation of the output crank 4 stops when it contacts the second limiting member 5b. In this embodiment, the state in which the output crank 4 contacts the second limiting member 5b and the switching part S2 contacts the first contact S11 is called the odd-number measurement state.

[0064] Next, although not shown in the diagram, the input shaft O1 rotates further counterclockwise and then stops.

[0065] Through the above process, the on-load tap changer 100 switches between the state in which the output crank section 4 is in contact with the first limiting member 5a and the state in which the output crank section 4 is in contact with the second limiting member 5b. Furthermore, the on-load tap changer 100 switches between the state in which the switching part S2 of the on switch 10 is in contact with the second contact S12 and the state in which the switching part S2 is in contact with the first contact S11.

[0066] Next, use Figures 6-13 The structure and operation of the switching switch 10 and the switching mechanism are described in detail.

[0067] like Figure 6 As shown, the switch 10 can be connected to both the odd-side tap T1 and the even-side tap T2. The odd-side tap T1 and the even-side tap T2 can also be configured in opposite directions.

[0068] The power-on switch conversion mechanism includes an A-side power-on switch SA, a B-side power-on switch SB, an R-side power-on switch SR, and a current-limiting resistor r. For ease of explanation, in Figures 6-12 , the switches in the A-side power-on switch SA, the B-side power-on switch SB, and the R-side power-on switch SR that are in the power-on state are marked with multiple oblique lines. In addition, the switches in the A-side power-on switch SA, the B-side power-on switch SB, and the R-side power-on switch SR that are in the off state are not marked with multiple oblique lines.

[0069] The A-side power-on switch SA, the B-side power-on switch SB, and the R-side power-on switch SR are electrically connected in parallel to each other. The A-side power-on switch SA is electrically connected to the first contact point S11 and the odd-side tap T1. The R-side power-on switch SR is electrically connected to the current-limiting resistor r. The conversion portion S2 is electrically connected to the R-side power-on switch SR with the current-limiting resistor r interposed therebetween. The B-side power-on switch SB is electrically connected to the second contact point S12 and the even-side tap T2.

[0070] The on switch 10 and the power-on switch conversion mechanism act in sequence as shown in Figures 6-12 . In addition, Figure 13 , the figures show that the first contact point S11, the second contact point S12, the A-side power-on switch SA, the B-side power-on switch SB, and the R-side power-on switch SR are in any one of the power-on state and the off state in the states shown in Figures 6-12

[0071] Figure 6 The state shown in is the even measurement state ES. In the even measurement state ES, the conversion portion S2 is in contact with the second contact point S12. The A-side power-on switch SA is off. The B-side power-on switch SB is on. The R-side power-on switch SR is off. Therefore, the current flows through the B-side power-on switch SB and flows to the even-side tap T2. Figure 6 The state shown in corresponds to the state of the on-load tap changer 100 shown in Figure 1 .

[0072] In the first transition state TS1 shown in Figure 7 , the conversion portion S2 is separated from the first contact point S11 and the second contact point S12, respectively. The A-side power-on switch SA is off. The B-side power-on switch SB is on. The R-side power-on switch SR is off. Therefore, the current flows through the B-side power-on switch SB and flows to the even-side tap T2. Figure 7 The state shown in corresponds to the state shown in Figure 3 .

[0073] In the second transition state TS2 shown in Figure 8 ​In the second transition state TS2 shown, the switching section S2 is in contact with the first contact point Sll. The A-side power supply switch SA is open. The B-side power supply switch SB is closed. The R-side power supply switch SR is open. Therefore, current flows through the B-side power supply switch SB and flows to the even-side tap T2. Figure 8 The state shown corresponds to Figure 4 The state shown corresponds to

[0074] In the third transition state TS3 shown, the switching section S2 is in contact with the first contact point Sll. The A-side power supply switch SA is open. The B-side power supply switch SB is closed. The R-side power supply switch SR is closed. Therefore, current flows through the R-side power supply switch SR, the current-limiting resistor r, and the first contact point Sll and flows to the odd-side tap Tl. In addition, current flows through the B-side power supply switch SB and flows to the even-side tap T2. Figure 9 In the fourth transition state TS4 shown, the switching section S2 is in contact with the first contact point Sll. The A-side power supply switch SA is open. The B-side power supply switch SB is open. The R-side power supply switch SR is closed. Therefore, current flows through the R-side power supply switch SR, the current-limiting resistor r, and the first contact point Sll and flows to the odd-side tap Tl.

[0075] Figure 10 In the fifth transition state TS5 shown, the switching section S2 is in contact with the first contact point Sll. The A-side power supply switch SA is closed. The B-side power supply switch SB is open. The R-side power supply switch SR is closed. Therefore, current flows through the R-side power supply switch SR, the current-limiting resistor r, and the first contact point Sll and flows to the odd-side tap Tl. In addition, current flows through the A-side power supply switch SA and flows to the odd-side tap Tl.

[0076] In the sixth transition state TS6 shown, the switching section S2 is in contact with the first contact point Sll. The A-side power supply switch SA is open. The B-side power supply switch SB is closed. The R-side power supply switch SR is open. Therefore, current flows through the B-side power supply switch SB and flows to the even-side tap T2. Figure 11

[0077] The state shown is the odd measurement state OS. In the odd measurement state OS, the switching section S2 is in contact with the first contact point Sll. The A-side power supply switch SA is closed. The B-side power supply switch SB is open. The R-side power supply switch SR is open. Therefore, current flows through the A-side power supply switch SA and flows to the odd-side tap Tl. In the odd measurement state OS, the switching section S2 is in contact with the first contact point Sll. The A-side power supply switch SA is closed. The B-side power supply switch SB is open. The R-side power supply switch SR is open. Therefore, current flows through the A-side power supply switch SA and flows to the odd-side tap Tl. Figure 12 In the state shown, the input clamp stops. Figure 12 The state shown corresponds to Figure 12 The state shown corresponds to Figure 5 The state shown is the state of the on-load tap changer 100.

[0078] As described above, the on-load tap changer 100 switches the target object of current flow from the even-side tap T2 to the odd-side tap Tl without cutting off the current. In addition, by the reverse operation to the above-described switching operation, the on-load tap changer 100 switches the target object of current flow from the odd-side tap Tl to the even-side tap T2 without cutting off the current. Furthermore, the on-load tap changer 100 can switch the target object of current flow from the even-side tap T2 to the odd-side tap Tl without cutting off the current by the operation shown in FIG. 6. Figures 6-12 ​The illustrated energizing switch mechanism has a so-called single-resistor three-switch structure, comprising an A-side energizing switch SA, a B-side energizing switch SB, an R-side energizing switch SR, and a current-limiting resistor r. The above-described energizing switch mechanism structure is one example. The structure of the energizing switch mechanism is not limited to the above-described single-resistor three-switch structure and may also be other structures.

[0079] Next, the effects of this embodiment will be explained.

[0080] According to the on-load tap converter 100 of Embodiment 1, such as Figure 1 As shown, the direction of the force acting on the first swing side 31 under the action of the first spring 6a is opposite to the direction of the force acting on the second swing side 32 under the action of the second spring 6b. Therefore, the force of the first spring 6a acting radially on the swing crank portion 3 is canceled out by the force of the second spring 6b. Therefore, the situation where the first spring 6a vibrates radially along the swing crank portion 3 can be suppressed. In addition, the radial direction of the swing crank portion 3 is a direction that intersects the length direction of the swing crank portion 3. Therefore, the vibration of the swing crank portion 3 can be suppressed.

[0081] Furthermore, since the vibration of the oscillating crank portion 3 can be suppressed, the mechanical durability of the on-load tap changer 100 is improved. Moreover, since the vibration of the oscillating crank portion 3 can be suppressed, the vibration of the switch 10 connected to the oscillating crank portion 3 can also be suppressed. Therefore, the reduction in the mechanical durability of the switch 10 can be prevented.

[0082] like Figure 1 As shown, the length of the first spring 6a is equal to the length of the second spring 6b. Therefore, the magnitude of the force acting on the first swing side 31 under the action of the first spring 6a is the same as the magnitude of the force acting on the second swing side 32 under the action of the second spring 6b. Therefore, the vibration of the swing crank part 3 under the action of the first spring 6a can be further suppressed.

[0083] The spring constant of the first spring 6a is equal to that of the second spring 6b. Therefore, the magnitude of the force acting on the first swing side 31 under the action of the first spring 6a is the same as the magnitude of the force acting on the second swing side 32 under the action of the second spring 6b. Therefore, the vibration of the swing crank 3 under the action of the first spring 6a can be further suppressed.

[0084] like Figure 1 as well as Figure 6As shown, the switching switch 10 can switch multiple contacts S1 that are in contact with the switching unit S2 by rotating the crank part 3. Therefore, by rotating the switching unit S2, the odd-numbered taps T1 and even-numbered taps T2 of the energizing switch switching mechanism can be switched. Therefore, it is possible to prevent one of the odd-numbered taps T1 and even-numbered taps T2 of the energizing switch switching mechanism from being worn out more than the other. That is, the balance of wear between the odd-numbered taps T1 and even-numbered taps T2 is improved. Therefore, it is possible to suppress the decrease in electrical durability and mechanical durability of the energizing switch switching mechanism.

[0085] Implementation Method 2

[0086] Next, use Figure 14 as well as Figure 15 The structure of the on-load tap converter 100 in Embodiment 2 will be described below. Unless otherwise specified, Embodiment 2 has the same structure and effects as Embodiment 1 described above. Therefore, structures identical to those in Embodiment 1 will be labeled with the same symbols and will not be described again.

[0087] In the on-load tap converter 100 of Embodiment 2, the switch 10 is connected to phases U, V, and W. That is, the switch 10 is connected to these three phases. The switch 10 is configured to centrally switch the connection states of each of phases U, V, and W.

[0088] like Figure 14 As shown, the multiple contacts S1 of the switch 10 include a U-phase first contact S1U1 and a U-phase second contact S1U2, a V-phase first contact S1V1 and a V-phase second contact S1V2, and a W-phase first contact S1W1 and a W-phase second contact S1W2. The U-phase first contact S1U1 and the U-phase second contact S1U2 are connected to the U phase. The V-phase first contact S1V1 and the V-phase second contact S1V2 are connected to the V phase. The W-phase first contact S1W1 and the W-phase second contact S1W2 are connected to the W phase. In this embodiment, the U-phase first contact S1U1, the U-phase second contact S1U2, the V-phase first contact S1V1, the V-phase second contact S1V2, the W-phase first contact S1W1, and the W-phase second contact S1W2 are arranged sequentially at intervals on a concentric circle centered on the switching axis O3.

[0089] like Figure 15As shown, the switching section S2 has a U-phase switching section S2U, a V-phase switching section S2V, and a W-phase switching section S2W. The first ends of the U-phase switching section S2U, the V-phase switching section S2V, and the W-phase switching section S2W are connected to the switching shaft O3. The U-phase switching section S2U, the V-phase switching section S2V, and the W-phase switching section S2W are connected in a Y shape. The second end of the U-phase switching section S2U can be in contact with the U-phase first contact point S1U1 and the U-phase second contact point S1U2. The second end of the V-phase switching section S2V can be in contact with the V-phase first contact point S1V1 and the V-phase second contact point S1V2. The second end of the W-phase switching section S2W can be in contact with the W-phase first contact point S1W1 and the W-phase second contact point S1W2.

[0090] The on-off switch 10 can switch the contact of the switching section S2 with any one of the U-phase first contact point S1U1 and the U-phase second contact point S1U2, any one of the V-phase first contact point S1V1 and the V-phase second contact point S1V2, and any one of the W-phase first contact point S1W1 and the W-phase second contact point S1W2. Specifically, the on-off switch 10 can switch the contact of the U-phase switching section S2U with any one of the U-phase first contact point S1U1 and the U-phase second contact point S1U2 by rotating the U-phase switching section S2U. The on-off switch 10 can switch the contact of the V-phase switching section S2V with any one of the V-phase first contact point S1V1 and the V-phase second contact point S1V2 by rotating the V-phase switching section S2V. The on-off switch 10 can switch the contact of the W-phase switching section S2W with any one of the W-phase first contact point S1W1 and the W-phase second contact point S1W2 by rotating the W-phase switching section S2W. In addition, Figure 15 The arrows show the range of rotation of the U-phase switching section S2U, the V-phase switching section S2V, and the W-phase switching section S2W of the switching section S2.

[0091] It is desirable that the U-phase first contact point S1U1, the U-phase second contact point S1U2, the V-phase first contact point S1V1, the V-phase second contact point S1V2, the W-phase first contact point S1W1, and the W-phase second contact point S1W2 of the plurality of contact points S1 are arranged in a concentric circle at intervals of 60 degrees. Further, the U-phase switching section S2U, the V-phase switching section S2V, and the W-phase switching section S2W are connected to the switching shaft O3 at intervals of 120 degrees. Therefore, by rotating the switching section S2 in a range of 60 degrees or more and less than 120 degrees, the contact of the switching section S2 with any one of the U-phase first contact point S1U1 and the U-phase second contact point S1U2, any one of the V-phase first contact point S1V1 and the V-phase second contact point S1V2, and any one of the W-phase first contact point S1W1 and the W-phase second contact point S1W2 can be switched.

[0092] In Embodiment 1, as described above, the conversion unit S2 can rotate in conjunction with the rotation of the swing crank unit 3. Furthermore, the rotation angle of the conversion unit S2 is the same as the rotation angle of the swing crank unit 3. In this embodiment, it is preferable that the angle by which the swing crank unit 3 can rotate is 60 degrees or more and less than 120 degrees. Therefore, the angle by which the conversion unit S2 can rotate is 60 degrees or more and less than 120 degrees. More preferably, the angle by which the swing crank unit 3 can rotate is 60 degrees or more and less than 70 degrees. Even more preferably, the angle by which the swing crank unit 3 can rotate is 70 degrees.

[0093] Next, the effects of this embodiment will be explained.

[0094] According to the on-load tap converter 100 of Embodiment 2, such as Figure 14 As shown, the switching switch 10 can switch the contact between the switching unit S2 and any one of the following: the first contact S1U1 and the second contact S1U2 of phase U; the first contact S1V1 and the second contact S1V2 of phase V; and the first contact S1W1 and the second contact S1W2 of phase W. Therefore, the switching switch 10 can switch the contacts S1 for phases U, V, and W respectively. Thus, the on-load tap changer 100 can switch the contacts S1 of all three phases. Therefore, since the on-load tap changer 100 can switch the contacts S1 of all three phases, it can be miniaturized compared to a case where the on-load tap changer 100 only switches contacts S1 of two or fewer phases.

[0095] like Figure 15 As shown, the oscillating crank 3 can rotate at an angle of 60 degrees or more and less than 120 degrees. Therefore, the switching unit S2 can switch the contacts S1 of each phase without crossing adjacent phases in the U, V, and W phases. If adjacent phases are crossed, a step voltage × will be generated during the switching of contacts S1. The potential difference is [not specified]. According to this embodiment, since the switching unit S2 can switch the contacts S1 of each phase without crossing adjacent phases in phases U, V, and W, the potential difference generated during the switching of contacts S1 is a step voltage × 1. Therefore, the potential difference generated during the switching of contacts S1 can be reduced. Consequently, the insulation performance of the on-load tap changer 100 is improved.

[0096] Implementation Method 3

[0097] Next, use Figures 16-21The structure of the on-load tap converter 100 in Embodiment 3 will be described below. Unless otherwise specified, Embodiment 3 has the same structure and effects as Embodiment 2 described above. Therefore, structures identical to those in Embodiment 2 will be labeled with the same symbols and will not be described again.

[0098] like Figure 16 As shown, the on-load tap converter 100 of this embodiment also includes a latch 7. The swing crank portion 3 is cross-shaped. The difference from the load-on-load tap converter 100 of Embodiment 1 is that the on-load tap converter 100 of this embodiment also includes a latch 7, and the swing crank portion 3 is cross-shaped.

[0099] The latch 7 includes a latch shaft O4, a first latch portion 71a and a second latch portion 71b, a latch spring 72, a first latch pin 73a, and a second latch pin 73b. In this embodiment, the latch 7 is capable of being opened and closed.

[0100] The oscillating crank portion 3 also includes an oscillating side third portion 33 and an oscillating side fourth portion 34. The oscillating side third portion 33 and the oscillating side fourth portion 34 clamp the output shaft O2 in a manner that intersects with the direction in which the oscillating side first portion 31 and the oscillating side second portion 32 clamp the output shaft O2. Ideally, the direction in which the oscillating side third portion 33 and the oscillating side fourth portion 34 clamp the output shaft O2 is orthogonal to the direction in which the oscillating side first portion 31 and the oscillating side second portion 32 clamp the output shaft O2.

[0101] The third part 33 on the swing side can contact the first latching pin 73a. The fourth part 34 on the swing side can contact the second latching pin 73b. By rotating around the output shaft O2, the swing crank 3 can switch between the state in which the third part 33 on the swing side is in contact with the first latching pin 73a and the state in which the fourth part 34 on the swing side is in contact with the second latching pin 73b.

[0102] The output crank portion 4 can be engaged with the second latch portion 71b while the third part 33 on the swing side is in contact with the first latch pin 73a. The output crank portion 4 can be engaged with the first latch portion 71a while the fourth part 34 on the swing side is in contact with the second latch pin 73b.

[0103] Specifically, the output-side second portion 42 can be engaged with the first latch portion 71a and the second latch portion 71b respectively. When the output-side second portion 42 is in contact with the first limiting member 5a, the output-side second portion 42 is engaged with the first latch portion 71a. When the output-side second portion 42 is in contact with the second limiting member 5b, the output-side second portion 42 is engaged with the second latch portion 71b.

[0104] The first latch portion 71a and the second latch portion 71b are configured to be rotatable about the latch shaft O4. The length direction of the first latch portion 71a crosses the length direction of the second latch portion 71b. The first latch portion 71a and the second latch portion 71b are linked by the latch spring 72.

[0105] The first latch portion 71a is capable of retaining the output crank portion 4. The first latch portion 71a is capable of contacting the first stopper 5a. The first latch portion 71a has a first-latch-portion-side first portion 71a1 and a first-latch-portion-side second portion 71a2. The first-latch-portion-side second portion 71a2 sandwiches the first-latch-portion-side first portion 71a1 with the latch shaft O4.

[0106] The second latch portion 71b is capable of retaining the output crank portion 4. The second latch portion 71b is capable of contacting the second stopper 5b. The second latch portion 71b has a second-latch-portion-side first portion 71b1 and a second-latch-portion-side second portion 71b2. The second-latch-portion-side second portion 71b2 sandwiches the second-latch-portion-side first portion 71b1 with the latch shaft O4.

[0107] The first latch pin 73a is disposed at the first-latch-portion-side first portion 71a1. The first latch pin 73a is capable of contacting the swing-side third portion 33. The second latch pin 73b is disposed at the second-latch-portion-side first portion 71b1. The second latch pin 73b is capable of contacting the swing-side fourth portion 34. The first latch pin 73a and the second latch pin 73b are disposed apart from each other. The swing-side second portion 32 is inserted between the first latch pin 73a and the second latch pin 73b.

[0108] The latch spring 72 links the first-latch-portion-side second portion 71a2 and the second-latch-portion-side second portion 71b2. In a state in which the output-side second portion 42 is retained by either of the first latch portion 71a and the second latch portion 71b, the latch spring 72 is stretched more than in a normal state. Thus, in the state in which the output-side second portion 42 is retained by either of the first latch portion 71a and the second latch portion 71b, the first latch portion 71a and the second latch portion 71b are forced by the latch spring 72.

[0109] The on-load tap changer 100 is capable of switching between a state in which the output crank portion 4 is retained by the first latch portion 71a and a state in which the output crank portion 4 is retained by the second latch portion 71b by the rotation of the swing crank portion 3 to force the latch spring 72.

[0110] More specifically, as Figure 16 and Figure 17As shown, the first latching portion 71a has a first flat portion 76a and a first protrusion 77a. The first protrusion 77a protrudes from the first flat portion 76a toward the output shaft O2. The output-side second portion 42 is engaged with the first latching portion 71a by its front end engaging with the first flat portion 76a and the first protrusion 77a. The second latching portion 71b has a second flat portion 76b and a second protrusion 77b. The second protrusion 77b protrudes from the second flat portion 76b toward the output shaft O2. The output-side second portion 42 is engaged with the second latching portion 71b by engaging with the second flat portion 76b and the second protrusion 77b.

[0111] like Figure 18 As shown, when viewed from the side, the connecting rod 2, the output crank 4, and the latch 7 are stacked in sequence. Figure 18 This is viewed from the output shaft O2 side relative to the input shaft O1. Figure 16 The image shows a side view of the on-load tap changer 100. A first spring 6a and a second spring 6b are connected to the bottom surface of the oscillating crank portion 3. When viewed from the side, the first spring 6a and the second spring 6b are at the same height. When viewed from the side, the front ends of each of the first latch pin 73a and the second latch pin 73b overlap with the bottom surface of the oscillating crank portion 3. Therefore, the front ends of each of the first latch pin 73a and the second latch pin 73b can contact the oscillating crank portion 3.

[0112] Next, use Figure 16 as well as Figures 19-21 The operation of the on-load tap converter 100 in Embodiment 3 will be explained.

[0113] First of all, Figure 16 In the even-numbered side measurement state shown, the first latch pin 73a is in contact with the third part 33 on the swing side. The second part 42 on the output side is locked to the second latch part 71b. The switching part S2 is in contact with the second contact S1U2 of phase U, the second contact S1V2 of phase V, and the second contact S1W2 of phase W. The first spring 6a, the second spring 6b, and the latch spring 72 are stretched compared to the normal state.

[0114] Next, as Figure 19 As shown, the input shaft O1 rotates counterclockwise. Therefore, the switching unit S2 rotates. Consequently, the switching unit S2 separates from the U-phase second contact S1U2, the V-phase second contact S1V2, and the W-phase second contact S1W2.

[0115] Furthermore, under the action of the input shaft O1 rotating counterclockwise, the first spring 6a and the second spring 6b are further stretched, thus increasing the force in the direction that causes the output crank 4 to rotate counterclockwise. However, since the second part 42 on the output side is locked to the second latch part 71b, the output crank 4 does not rotate. Therefore, the elastic energy of the first spring 6a and the second spring 6b increases. That is, the first spring 6a and the second spring 6b are energy stored.

[0116] Furthermore, as the input shaft O1 rotates counterclockwise, the first latching part 71a rotates counterclockwise as well. The rotation of the first latching part 71a stops when it comes into contact with the first limiting member 5a. The second latching part 71b rotates clockwise.

[0117] Next, as Figure 20 As shown, the input shaft O1 rotates further counterclockwise. This causes the second latch pin 73b, connected to the second latch portion 71b, to contact the swing-side fourth portion 34. Due to the counterclockwise rotation of the swing crank portion 3, the second latch pin 73b, which contacts the swing crank portion 3, rotates counterclockwise. Furthermore, the input shaft O1 rotates further counterclockwise. This causes the switching portion S2 to contact the U-phase first contact S1U1, the V-phase first contact S1V1, and the W-phase first contact S1W1.

[0118] Next, as Figure 21 As shown, the input shaft O1 rotates further counterclockwise. This causes the second part 32 on the swing side to separate from the second latch part 71b. That is, the locking between the output crank part 4 and the second latch part 71b is released. The elastic energy stored in the first spring 6a and the second spring 6b is released, causing the output crank part 4 to rotate counterclockwise. The counterclockwise rotation of the output crank part 4 stops when it comes into contact with the first limiting member 5a.

[0119] When the output crank 4 rotates counterclockwise, it contacts the first latch pin 73a and pushes the first latch 71a clockwise. This causes the first latch 71a to rotate clockwise. Although a counterclockwise force generated by the latch spring 72 also acts on the first latch 71a, the clockwise force generated by the output crank 4 is greater, causing the first latch 71a to rotate clockwise. When the output crank 4 stops in contact with the first stop member 5a, the first latch 71a rotates counterclockwise under the action of the latch spring 72. This engages the first latch 71a with the output crank 4. Furthermore, although not shown, the energizing switch mechanism connected to the output crank 4 operates, switching the energizing circuit from the even-numbered side to the odd-numbered side.

[0120] Next, although not shown, the input shaft O1 rotates further and stops in the odd-number measurement state. Furthermore, the operation of the energizing switch mechanism in this series of actions is the same as that used in Embodiment 1. Figures 6-13 The actions described are the same.

[0121] Next, the effects of this embodiment will be explained.

[0122] According to the on-load tap converter 100 of Embodiment 3, such as Figure 16 As shown, by rotating the oscillating crank 3, the latch spring 72 is forced, allowing the output crank 4 to switch between being locked with the first latch 71a and being locked with the second latch 71b. Therefore, the operating angle of the output crank 4 can be determined by the first latch 71a and the second latch 71b. That is, the release position of the elastic energy of the first spring 6a and the second spring 6b can be determined by the first latch 71a and the second latch 71b. Therefore, the switching action of the on-load tap changer 100 can be easily determined. Furthermore, the timing of the switching action of the on-load tap changer 100 can be easily designed.

[0123] like Figures 19-21 as well as Figure 18 As shown, the first spring 6a and the second spring 6b are not in contact with each other. Therefore, as ​ As shown, when viewed from the side, the height positions of the first spring 6a and the second spring 6b can be set to be the same. Therefore, the on-load tap changer 100 can be miniaturized in the height direction.

[0124] It should be understood that although specific embodiments of this disclosure have been described, the embodiments disclosed herein are illustrative in all respects and do not constitute a limitation. The scope of this disclosure is defined by the claims, and this disclosure includes all modifications within the meaning and scope equivalent to the claims.

Claims

1. A load tap changer, characterized by, comprises: an input shaft that is rotatable; an output shaft that is disposed separately from the input shaft; an input crank portion that is coupled to the input shaft; a link portion that is coupled to the input crank portion at a position different from the position at which the input shaft is coupled; a swing crank portion that is coupled to the link portion and is rotatable about the output shaft, and that includes a swing-side first portion, and a swing-side second portion that sandwiches the output shaft with the swing-side first portion; a first spring that is coupled to the swing-side first portion; a second spring that is coupled to the swing-side second portion; an output crank portion that includes an output-side first portion that is coupled to the first spring, and an output-side second portion that sandwiches the output shaft with the swing-side first portion and is coupled to the second spring, and that is rotatable about the output shaft; first and second stoppers that are contactable with the output-side second portion; and an on-off switch that is coupled to the swing crank portion, and that includes a plurality of contacts, and a switching portion that is contactable with the plurality of contacts, rotation of the input shaft is transmitted by the input crank portion and the link portion, whereby the swing crank portion is rotatable, rotation of the swing crank portion is transmitted to the output crank portion by the first spring and the second spring, whereby the output-side second portion is rotatable in contact with either of the first and second stoppers, the on-off switch is switchable by rotation of the swing crank portion to switch the plurality of contacts in contact with the switching portion, a direction of force acting on the swing-side second portion by the second spring is opposite to a direction of force acting on the swing-side first portion by the first spring, the plurality of contacts of the on-off switch include a U-phase first contact and a U-phase second contact connected to a U-phase, a V-phase first contact and a V-phase second contact connected to a V-phase, and a W-phase first contact and a W-phase second contact connected to a W-phase, the on-off switch is switchable to contact either of the U-phase first contact and the U-phase second contact, either of the V-phase first contact and the V-phase second contact, and either of the W-phase first contact and the W-phase second contact with the switching portion, the switching portion is rotatable in conjunction with rotation of the swing crank portion, the U-phase first contact, the U-phase second contact, the V-phase first contact, the V-phase second contact, the W-phase first contact, and the W-phase second contact of the plurality of contacts are arranged in sequence at intervals of 60 degrees on concentric circles, the swing crank portion is rotatable by an angle of 60 degrees or more and less than 120 degrees.

2. The on-load tap changer according to claim 1, wherein a length of the first spring is equal to a length of the second spring. ​ 3. The on-load tap changer according to claim 1 or 2, wherein a spring constant of the first spring is equal to a spring constant of the second spring.

4. The on-load tap changer according to claim 1 or 2, wherein the on-load tap changer further comprises a latch including a latch shaft, a first latch portion and a second latch portion configured to be rotatable about the latch shaft, a latch spring, a first latch pin, and a second latch pin, the first latch portion has a first latch portion side first portion and a first latch portion side second portion sandwiching the latch shaft with the first latch portion side first portion, and the first latch portion is capable of latching the output crank portion, the second latch portion has a second latch portion side first portion and a second latch portion side second portion sandwiching the latch shaft with the second latch portion side first portion, and the second latch portion is capable of latching the output crank portion, the first latch pin is disposed at the first latch portion side first portion, the second latch pin is disposed at the second latch portion side first portion, the latch spring links the first latch portion side second portion and the second latch portion side second portion, the swing crank portion further comprises a swing side third portion and a swing side fourth portion sandwiching the output shaft in a direction crossing the output shaft sandwiched by the swing side first portion and the swing side second portion, the swing side second portion is inserted between the first latch pin and the second latch pin, the swing side third portion is capable of contacting the first latch pin, the swing side fourth portion is capable of contacting the second latch pin, the swing crank portion is capable of switching between a state where the swing side third portion contacts the first latch pin and a state where the swing side fourth portion contacts the second latch pin by rotating about the output shaft, the output crank portion is capable of latching with the second latch portion in the state where the swing side third portion contacts the first latch pin, and is capable of latching with the first latch portion in the state where the swing side fourth portion contacts the second latch pin, the output crank portion is capable of switching between a state where the output crank portion latches with the first latch portion and a state where the output crank portion latches with the second latch portion by the latch spring being forced by the rotation of the swing crank portion.

5. The on-load tap changer according to claim 3, wherein the on-load tap changer further comprises a latch including a latch shaft, a first latch portion and a second latch portion configured to be rotatable about the latch shaft, a latch spring, a first latch pin, and a second latch pin, the first latch portion has a first latch portion side first portion and a first latch portion side second portion sandwiching the latch shaft with the first latch portion side first portion, and the first latch portion is capable of latching the output crank portion, The second latch portion has a second latch portion side first portion and a second latch portion side second portion that sandwiches the latch shaft with the second latch portion side first portion, and the second latch portion can lock the output crank portion, The first latch pin is arranged in the first latch portion side first portion, The second latch pin is arranged in the second latch portion side first portion, The latch spring links the first latch portion side second portion and the second latch portion side second portion, The swing crank portion further includes a swing side third portion and a swing side fourth portion that sandwich the output shaft in a direction that crosses the direction in which the swing side first portion and the swing side second portion sandwich the output shaft, The swing side second portion is inserted between the first latch pin and the second latch pin, The swing side third portion can contact the first latch pin, The swing side fourth portion can contact the second latch pin, The swing crank portion can switch between a state in which the swing side third portion contacts the first latch pin and a state in which the swing side fourth portion contacts the second latch pin by rotating about the output shaft, The output crank portion can be locked by the second latch portion in the state in which the swing side third portion contacts the first latch pin, and can be locked by the first latch portion in the state in which the swing side fourth portion contacts the second latch pin, The output crank portion can be locked by the first latch portion and the second latch portion by the force of the latch spring that is applied by the rotation of the swing crank portion. The output crank portion can be locked by the first latch portion and the second latch portion by the force of the latch spring that is applied by the rotation of the swing crank portion.

Images