JPH0731475Y2 - Pull string fixing device for pole switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a drawstring fixing device for a switch installed on a pillar.

[Prior Art] A conventional drawstring fixing device is disclosed in Japanese Utility Model Publication No. Sho 63-38499. A support frame is fixed to the center of the front surface of the receiving frame that constitutes this drawstring fixing device, and a pair of left and right vertically elongated holes in the center of the push plate are loosely fitted to both side pieces of the support frame. An eccentric cam is rotatably supported on the support frame protruding from the push plate, and a lever connected to the cam is operated to press the push plate against the drawstring via the eccentric cam to the receiving frame. The drawstring is fixed so that it cannot be operated.

[Problems to be Solved by the Invention] However, since the front surface of the receiving frame and the rear surface of the pressing plate are provided with concavities and convexities facing each other, when the drawstring is fixed by the drawstring fixing device, the drawstring retains moisture. If it freezes in the contained state, an uneven corrugated shape will be formed. Therefore, even if the drawstring can be operated by rotating the lever upward, the drawstring formed by being frozen in a waveform interferes with the concave and convex portions facing the receiving frame and the pressing plate, so that the drawstring can be operated. It may be impossible.

An object of the present invention is to provide a drawstring fixing device for a pole switch that can reliably operate the string even if the string freezes.

[Means for Solving the Problems] In order to solve the above-mentioned object, a first invention of the present application is provided with a pair of holding members for holding and releasing an operating drawstring of a switch, and a holding side of at least one holding member. The gist of the invention is to provide a contact surface on which the drawstring extends linearly and to link at least one of the pair of holding members to an operation lever that is supported so as to be externally operable.

The gist of a second invention is that a toggle mechanism for selectively urging the operating lever in the holding direction or the opening direction is linked.

According to a third aspect of the invention, two sets are arranged with the pair of holding members as one set corresponding to the two drawstrings suspended from the opening / closing lever of the switch, and at least one holding member of both sets is common. Its gist is that it is linked to the control lever of.

In a fourth invention, one holding member is rotatably supported on a support shaft that fixes the other holding member, and one end of the one holding member is laterally moved from a side portion along which a drawstring of the other holding member is provided. A projecting portion is provided with a sandwiching portion at one end of the projecting one sandwiching member, and the gripping portion and the side portion of the other sandwiching member sandwich or release the drawstring by the rotation of the one sandwiching member. To do.

[Operation] Therefore, in the operation of the first invention, when the operation lever is operated, at least one of the pair of holding members operates. By the operation of this one holding member, the drawstring along the linear contact surface provided on at least one holding member is held or released.

The operation of the second invention is that the holding member is selectively urged in the holding direction or the opening direction by the toggle mechanism.

According to the operation of the third invention, at least one of the sandwiching members of the two sandwiching members arranged as one pair is linked to the operation lever, and when the operation lever is operated, one sandwiching member is interlocked. Pinch or release the two drawstrings.

According to the operation of the fourth invention, when the operation lever is operated, one holding member provided on the support shaft for fixing the other holding member is rotated. Then, the holding portion at one end of the one holding member protruding laterally from the contact surface of the other holding member along which the drawstring extends rotates. The drawstring is held or released by the holding portion and the contact surface of the other holding portion.

[Embodiment] A first embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, a drawstring fixing device 1 (a position of about 3 m above the ground in the present invention) is fixed to a utility pole P by a fixing band 2.

As shown in FIGS. 3 and 4, the main body case 3 of the drawstring fixing device 1 is composed of a square box-shaped front box 3a and a back plate 21 that closes a rear opening of the front box 3a. Bolts 22 screwed from the back surface of back plate 21 to four fixing members 19 protruding from the inner surface of 3a
It is closed by.

Incidentally, 1a is a square ring-shaped packing interposed between the front box 3a and the back plate 21.

As shown in FIG. 2, the front box 3a and the back plate of the main body case 3
A pair of left and right shafts 4 are rotatably supported between the 21.
The front end of each shaft 4 is projected on the surface of the front box 3a of the main body case 3, and the first holding member 5 is fixed to the projecting end.

A columnar holding portion 6 is integrally fixed to the lower end (lower portion in FIG. 2) of the holding member 5, and a locking portion 7 is formed to extend at the upper end. On the surface of the front box 3a of the main body case 3, a restricting member 26 that abuts on the locking portion 7 of the first holding member 5 is provided at a position above the shaft 4.

Further, when the first holding member 5 rotates the shaft 4 in the direction of the arrow T in FIG. 2 from the state where the holding portion 6 is located at the lowermost position, the second holding member 27 that comes into contact with the holding portion 6 is the main body case. On the surface of the front box 3a of No. 3, it is fixed at a position to the left of the shaft 4. Then, the first holding member 5 and the second holding member
A pair of cords R suspended from an operation handle of a switch (not shown) are inserted between the cords 27 and 27.

A contact surface 27a along which the string R extends along a straight line is formed on the side portion (the vertical direction in FIG. 2) of the second holding member 27.

Therefore, the string R is sandwiched and fixed by the first sandwiching member 5 and the second sandwiching member 27. Further, when the string R is sandwiched by the first sandwiching member and the second sandwiching member 27, the string R is linearly aligned with the contact surface 27a of the second sandwiching member 27.

It should be noted that in the vertical width direction of the main body case 3 in which the cord R is clamped by the first clamping member 5 and the second clamping member 27, the cord R is
A pair of guide members 28 for restricting the displacement in the width direction are provided. Further, as shown in FIG. 2, a female screw 28a is formed on the guide member 28 located on the left side of the central portion of the front surface of the front box 3a.

Further, in FIG. 2, a mounting member 29 is projectingly provided on the lower right side of the front surface of the front box 3a, and the mounting member 29 is formed with a female screw 29a.

As shown in FIG. 4, the guide plate 30 for guiding the cord R is tightened and fixed by bolts 31 which are respectively screwed into the guide member 28 having the female screw 28a formed therein and the mounting member 29. The lower portion of the guide plate 30 is curved outward so that the string R is not rubbed and cut when the string R is moved up and down.

As shown in FIG. 3, in the main body case 3, a reversing member 8 is fixed to the shaft 4 at the center thereof. Further, an operation lever 9 is fixed to one of the shafts 4 (the left side in FIG. 3). Then, while projecting to the outside from an opening 10 provided on the side surface of the main body case 3, a through hole 11 is transparently provided at the tip thereof.

The operating lever 9 is operated by inserting and locking the hook 33 provided at the tip of the operating rod 32 shown in FIG. 6 through the through hole 11 of the operating lever 9.

Further, a spring support member 12 is provided at the upper tip of each reversing member 8.
Are rotatably mounted by support pins 13.

A sliding groove 14 is formed at the tip of the spring support member 12 and extends in the longitudinal direction and has an opening at the tip. A support shaft is provided on the inner back surface of the front box 3a so that it is located in the sliding groove 14.
15 are fixed upright. Therefore, the sliding groove 14 of each spring support member 12 slides along the support shaft 15 as the reversing member 8 rotates.

A coil spring 17 is attached to each spring support member 12.
Is interposed, and both ends thereof are locked by the support shaft 15 and the locking portion 16 of the spring support member 12 in a stored state. Therefore, the first pinching member 5 fixed to the shaft 4 is rotated by the urging force of the coil spring 17 so that the string R can be operated either in an open state or a fixed state in which the string R cannot be operated. It is designed to selectively urge one side. Further, the spring support member 12 and the coil spring 17 form a toggle mechanism.

A base end of a connecting link 24 is rotatably supported by a pin 23 at the lower end of one reversing member 8 provided with the operating lever 9, and a long hole 25 extending in the longitudinal direction is provided at the distal end of the connecting link 24. Are formed. A pin 26a projecting from the lower end of the other reversing member 8 is slidably linked to the elongated hole 25.

Therefore, as shown by the dashed line in FIG. 2, when the operation lever 9 is rotated downward, the shaft 4 fixed to the operation lever 9 rotates in the direction of the arrow T, and
The other shaft 4 also rotates in the direction of the arrow T via 24. At this time, the coil spring 17 is accumulated by the support shaft 15 and the locking portion 16, and when the support pin 13 exceeds the dead point X, the accumulated force is released and the first clamping member 5 is released.
Rotate vigorously in the direction of the arrow T.

In addition, as shown in FIG.
At the upper part of the outer surface of 3a, "FRE
The letter “E” and “↑” indicating that the operation lever 9 is operated upward are drawn by paint, and the guide plate 30 indicates “LOCK” indicating the fixed state of the string R and the operation lever 9
"↓" is drawn by painting, which indicates that the button is operated downward.

As shown in FIGS. 1 and 7, a pair of supports for guiding a pair of cords R attached to both ends of the operation handle of the switch, respectively, on the upper portion of the electric pole P to which the drawstring fixing device 1 is fixed. A metal fitting S is provided.

The support metal fitting S is formed by bending a round bar into a ring shape, and a hooking member 35 capable of hooking an operating grip 34 attached to the lower end of the string R is erected and fixed at its tip end. There is.

Therefore, as shown in FIG. 1, when the cord R is not used, the operating grip 34 attached to the cord R is attached to the support fitting S.
The cord R can be hooked on the hooking member 35, and the operation of the string R can be prevented easily.

The operation of the drawstring fixing device 1 configured as described above will be described.

First, as shown in FIG. 5, when the drawstring fixing device 1 in which the string R can be operated is changed from the open state to the fixed state in which the string R cannot be operated, the hook 33 of the operating rod 32 is set to the operating lever. 9
It is locked in the through hole 11 and the operation lever 9 is rotated downward. Then, as shown in FIGS. 2 and 3, the reversing member 8 fixed to the one shaft 4 and the other reversing member 8 via the connecting link 24.
Rotate in the T arrow direction, and the first holding member 5 fixed to the shaft 4 rotates in the T arrow direction.

Therefore, the rotation of the support pin 13 causes the coil spring 17 interposed in the support member 12 to accumulate the force by the support shaft 15 and the locking portion 16, and when the support pin 13 exceeds the dead point X, the accumulated force is released. Then, the first holding member 5 and the reversing member 8 turn vigorously in the T arrow direction.

Therefore, the holding portions 6 of both the first holding members 5 rotate in the direction of the arrow T, and the string R is held and fixed by the second holding portion 27. That is, the string R is held in contact with the contact surface 27a of the second holding member 27 and the holding portion 6 and held. As a result, the string R is clamped and fixed in a state of being directly along the contact surface 27a of the second clamping member 27. Further, the urging force of the coil spring 17 firmly holds the string R in the sandwiched state.

Next, in the case of changing the state in which the string R is fixed to the operable open state, the operation reverse to the above operation is performed. That is, the operation lever 32 is operated to rotate the operation lever 9 upward. Then, each reversing member 8 and the first holding member 5 provided on both shafts 4 rotate in the direction opposite to the arrow T.

Then, when the support pin 13 crosses the dead point X, both the reversing members 8 and the first sandwiching members 5 rotate vigorously in the counter T direction. Then, the locking portions 7 of both the first sandwiching members 5 are brought into contact with and locked to the regulating member 26 by the urging force of the coil spring 17, and the rotation of both shafts 4 is regulated to bring the cord R into an open state in which it can be operated. Become.

In this way, the holding part 6 of the first holding member 5 moves the string R to the second position.
Since the pinching member 27 is clamped so as to follow the contact surface 27a along the straight line, it is not fixed to a shape such that the cord R freezes due to low temperature and becomes inoperable. R can be operated reliably.

Further, not only can the clamping and fixing of the string R be firmly held by the urging force of the coil spring 17, but also a malicious mischief such as pulling the string R to open the switch to cause a power failure can be prevented. it can.

Further, the string R can be easily clamped or released by operating the operating lever 32 of the drawstring fixing device 1, and the pair of first clamping members 5 can be simultaneously operated by the connecting link 24. it can.

Next, a second embodiment will be described with reference to FIG.
The same components as those of the first embodiment or the components corresponding to those of the first embodiment are designated by the same reference numerals and the description thereof is omitted.

A shaft 4 is rotatably inserted and supported on the left side of the front box 3a of the body case 3, and a rotating lever 36 is fixed to the shaft 4. A spring support member 12 is rotatably attached to the tip of the rotation lever 36 by a support pin 13.

One end of a connecting link 24 is connected to the support pin 13, and a pair of upper and lower drive members 38 are rotatably supported by a pin 37 at the other end. The first holding member 5 is rotatably supported by a pin 37 at the upper and lower ends of each drive member 38.

The center of each of the first holding members 5 is rotatably supported by a support shaft 39 fixed to the center of the second holding member 27 in the width direction. In addition, a second member is provided on each end of the first holding member 5.
The columnar holding portions 6 that come into contact with the holding members 27 of FIG.

The second holding member 27 is formed in a rectangular parallelepiped shape extending in the vertical direction and is fixed to the back surface of the front box 3a. Further, abutting surfaces 27a each having a flat surface are formed on both side surfaces of the second holding member 27 in the width direction so that the string R is linearly aligned.

Therefore, in order to open the pair of strings R from the sandwiched state shown in FIG. 8 so as to be operable, the shaft support 4 is rotated in the Y arrow direction via the operation lever (not shown).
Rotates counterclockwise. Then, the coil spring 17 is accumulated by the support shaft 15 and the locking portion 16, and when the support pin 13 crosses the dead point X, the connecting link 24 vibrates to the left vigorously. Then, the first holding members 5 supported by the support shaft 39 rotate in the Q1 and Q2 arrow directions via the drive member 38, respectively.

As a result, the holding portions 6 that hold and fix the pair of strings R are separated from the second holding member 27, that is, the holding portion 6 is separated from the contact portion 27a of the second holding member 27.
The pair of strings R is in an operable open state.

Further, when the pair of strings R is clamped and fixed, the shaft 4 is rotated in the direction opposite to the arrow Y. When the support pin 13 crosses the dead point X, the connecting link 24 and the drive member 28
The respective first holding members 5 rotate in the directions opposite to the Q1 and Q2 arrows via. Therefore, the sandwiching portion 6 of the first sandwiching member 5 presses the pair of strings R against the contact surface 27a of the second sandwiching member 27 so as to form a straight line, thereby sandwiching and fixing.

As described above, also in the second embodiment, since the pair of strings R can be clamped and fixed in a straight line state, the strings R can be fixed at a low temperature.
It is possible to prevent the string R from being frozen and making the operation of the string R impossible.

Further, the urging force of the coil spring 17 can firmly hold the pair of strings R in the sandwiched state.

Furthermore, if the configuration of the second embodiment is adopted, the dimension of the drawstring fixing device 1 in the width direction can be made smaller than that of the first embodiment. As a result, when the drawstring fixing device 1 in the second embodiment is attached to the electric pole P, the drawstring fixing device 1 does not project to both sides of the electric pole P, so that the appearance at the time of attachment can be improved.

Next, a third embodiment will be described with reference to FIG.

A pair of second holding members 27, 27 'are fixed to the left and right sides of the front box 3a. The second holding members 27, 27 'are formed in a rectangular parallelepiped shape and fixed to the front box 3a in the vertical direction. Further, contact surfaces 27, 27 'for linearly extending the string R are formed on one side surface of the second holding members 27, 27' with which the string R abuts.

A connecting link which is movable in the width direction of the main body case 3 by a support pin 13 is provided at the tip of a rotary lever 36 fixed to the shaft 4.
24 is rotatably supported. Also, the connection link
At both ends of 24, long holes 40, 4 extending in the longitudinal direction of the connecting link 24.
0'is transparently provided.

Pins 41, 41 'are inserted into the long holes 40, 40',
Base ends of a pair of upper and lower drive members 38, 38 'are rotatably supported by the pins 41, 41', respectively. At one end of the pair of drive members 38, 38 ', one ends of L-shaped locking members 42, 42' as first holding members are rotatably connected by pins 37, 37 '. There is. This locking member 42, 42 '
Is rotatably supported at its corners by support shafts 39, 39 ', and the other end and the contact surface 27a of the second holding member 27, 27'.
The string R is clamped and fixed by and.

Further, in the drawstring fixing device 1 of FIG. 9, the long holes 40, 40 '
The pins 41, 41 'which are inserted through the holes are elongated holes 40, 40' due to the urging force of the coil spring 17 interposed in the spring support member 12.
It is designed to be driven in the left-right direction via the left and right ends of the.

Therefore, when the shaft 4 is rotated in the arrow C direction, the spring support member 12 is rotated counterclockwise and the connecting link 24 is moved leftward along the pins 41, 41 '. When the support pin 13 crosses the dead point X, the right end of the elongated hole 40 on the left side of the connecting link 24 presses the pin 41 by the biasing force of the coil spring 17. Then, a pair of drive members
Since the members 38 rotate in the directions of opening each other, the locking member 42 rotates about the support shaft 39 in the directions of arrows D1 and D2.

On the other hand, when the connecting link 24 is moved to the left, the right long hole 4
0'The right end pulls the pin 41 'by moving it to the left,
The drive members 38 'rotate in the direction of closing each other, and
The reference numeral 42 'rotates about the support shaft 39' in the directions of arrows E1 and E2, respectively.

As a result, the locking members 42, 4 that clamp and fix the string R linearly with respect to the contact surfaces 27a, 27a 'of the second clamping members 27, 27'.
The other end of 2'is separated from the string R. Therefore, the pair of strings R is in an operable open state. Further, the operation opposite to the above may be performed in order to set the fixed state.

That is, when the shaft 4 is rotated in the direction opposite to the arrow C, the pin on the left side is rotated.
41 is in contact with the left end of the long hole 40 of the connecting link 24 and is pulled by the biasing force of the coil spring 17, so that the pair of locking members 42 respectively rotate in the opposite D1 and D2 arrow directions. And
Since the right pin 41 'is pressed by the right end of the elongated hole 40' of the connecting link 24, the pair of locking members 42 'rotate in the opposite E1 and E2 arrow directions, respectively.

As a result, the other ends of the locking members 42, 42 'and the second holding members 27,
The abutment surfaces 27a, 27a 'of the 27' hold the string R in a straight line.

Also in the third embodiment, the contact surface 2 of the second character members 27, 27 '
Since the string R is placed along 7a, 27a 'and the locking members 42, 42' make the string R in a straight line state, the string R is connected due to low temperature and fixed to a shape such that the string R cannot be operated. Never be done. Further, the clamping state can be firmly held by the biasing force of the coil spring 17.

Next, a fourth embodiment will be described with reference to FIG.

On the right side of the back surface of the front box 3a, a second holding member 27 having a rectangular parallelepiped shape is formed on the upper right side and the lower left side of the hanging string R.
A and 27B are fixed respectively. Each second clamping member 27
The first holding members 5A and 5B and the driven lever are provided on the side surfaces of A and 27B.
44A and 44B are rotatably supported by a support shaft 39, and a rectangular parallelepiped holding portion 43 swings through a pin 23 at one end of both members 5A, 44A, 5B and 44B extending toward the cord R side. It is movably supported.

Therefore, the first holding member 5A, the second holding member 27A,
The driven lever 44A, the sandwiching portion 43, the first sandwiching member 5B, the second sandwiching member 27B, the driven lever 44B, and the sandwiching portion 43 constitute a parallel four-bar link linking the second sandwiching members 27A and 27B. There is.

The other end of the driven lever 44A disposed on the upper right side extends to the right in the drawing, and the pin 23 and the connecting link 45
Is linked to the first sandwiching member 5B located below. Further, one end of the first holding member 5A located above is connected to the right end of the rotating lever 36 via a pin 23 and a connecting link 24.

Each member arranged around the left side cord R is given the same or corresponding material sign arranged around the right side string, and the description thereof is omitted. Only different points will be described. That is, the right end of the first holding member 5A extends rightward, and the pin 23
Also, it is linked to the left end of the rotating lever 36 via a connecting link 46. The left end of the first holding member 5B extends to the left, and the driven lever is connected via the pin 23 and the connecting link 45.
It is linked to 44A.

Therefore, when the shaft 4 is rotated in the arrow F direction by the operation lever (not shown) from the sandwiched state of FIG. 10, the first sandwiching members 5A, 5B and the driven levers 44A, 44B on the upper and lower left sides of the front box 3a move to the support shaft 39. Rotate in the direction of the arrow G. Further, the driven levers 44A, 44B and the first holding members 5A, 5B arranged on the upper and lower right sides of the front box 3a respectively rotate about the support shaft 39 in the arrow H direction.

Therefore, the holding member 43 that holds the string R separates from the string R, and the string R is opened so that the string R can be operated.

Further, in order to put the pair of strings R into the sandwiched state, an operation opposite to the above is performed and the shaft 4 is rotated in the direction opposite to the arrow F direction. Then,
The first holding members 5A, 5B on the right and left sides of the front box 3a and the driven levers 44A, 44B rotate in the direction opposite to the arrow H, and the first holding members 5A, 5B on the left and right sides of the front box 3a and the driven levers 44A, 44B rotates in the direction opposite to the arrow G, respectively.

Therefore, the sandwiching portion 43 has the contact surface 27a of the second sandwiching member 27.
The string R is clamped by and so that it cannot be operated.

Also in the fourth embodiment, since the holding portion 43 causes the string R to directly follow the contact surface 27a of the second holding member 27, the string R can be operated even if the string R freezes due to a low temperature. There is no shape that cannot be done.

In each embodiment, the second holding members 27, 27 ', 27A,
27B is fixed to the front box 3a, but the second holding members 27, 27 ', 27
It is also possible to connect A and 27B to the operation lever 9 so that they can be externally operated similarly to the first holding members 5, 5A and 5B.

The present invention is not limited to the above-mentioned embodiment, and can be arbitrarily modified within a range not departing from the spirit of the present invention.

[Effects of the Invention] As described above in detail, in the first invention, since the drawstring is clamped and fixed to the abutting surface of at least one of the sandwiching members along the straight line, the drawstring is held in the clamped state. It has an effect that it does not become inoperable even when frozen.

In the second invention, one of the holding members can be selectively urged in the opening direction or the holding direction by the toggle mechanism, and in the holding state, the drawstring can be firmly held and fixed by the urging force of the toggle mechanism. .

In the third invention, a pair of sandwiching members constitutes one set,
By arranging in pairs, the pair of drawstrings can be clamped in a stable state.

In the fourth invention, it is possible to rotate with respect to the other sandwiching member, which is one sandwiching member, and sandwich the drawstring along the contact surface formed on the side portion of the other sandwiching member in a linear state. Therefore, there is an effect that even if the drawstring freezes in the sandwiched state, the drawstring does not become inoperable.

[Brief description of drawings]

1 to 7 show a first embodiment of the present invention, FIG. 1 is a schematic view showing a state in which a drawstring fixing device is attached to an electric pole, and FIG. 2 shows a pair of fixing mechanisms provided on an outer surface of a main body case. Fig. 3 is a front sectional view showing the structure of a pair of biasing mechanism and freezing mechanism inside the main body case as seen from the back side, and Fig. 4 is a partially cutaway sectional view of the drawstring fixing device. FIG. 6 is a plan view of a drawstring fixing device, FIG. 6 is a plan view showing an operating rod, FIG. 7 is a side view showing a shape of a support fitting, and FIG. 8 is a configuration diagram showing a second embodiment of the drawstring fixing device. FIG. 9 is the third of the drawstring fixing device.
FIG. 10 is a configuration diagram showing an embodiment, and FIG. 10 is a configuration diagram showing a fourth embodiment of the drawstring fixing device. 1 ... drawstring fixing device, 5, 5A, 5B, 42, 42 '... first holding member as one holding member, 6, 43 ... holding portion, 12 ...
Spring support member, 17 ... Coil spring, 24 ... Connection link, 27, 27 ', 27A, 27B ... Second holding member as the other holding member, 27a, 27a' ... Contact surface, R ... …string.

Claims (4)

[Scope of utility model registration request] 1. A pair of sandwiching members for sandwiching and opening an operating drawstring of a switch, wherein at least one sandwiching member is provided with an abutting surface along which the drawstring is linearly provided on the sandwiching side portion. At least one of the holding members is linked to an operation lever that is supported so that it can be operated externally. 2. The drawstring fixing device for a pole switch according to claim 1, wherein the operating lever is linked with a toggle mechanism for selectively urging the operating lever in a clamping direction or an opening direction. 3. A pair of sandwiching members corresponding to the two drawstrings suspended from the closing and opening lever of the switch are arranged in two sets, and at least one sandwiching member of both sets is common. The drawstring fixing device for a pole switch according to claim 1 or 2, wherein the drawstring fixing device is linked to an operation lever. 4. A holding shaft rotatably supporting one holding member on a support shaft for fixing the other holding member, and one end of the one holding member projects laterally from a side portion along which a drawstring of the other holding member extends. A holding portion is provided at one end of the protruding one holding member, and the holding portion and the side portion of the other holding member hold or release the drawstring by the rotation of the one holding member. Item 3. A pull string fixing device for a pole switch according to Item 1 or 2.