JP6243138B2 - Horizontal blind - Google Patents

Description

  The present invention relates to a horizontal blind of a high shielding type.

  In the horizontal blind, the amount of solar radiation taken into the room is adjusted by moving up and down and tilting multiple slats supported by a ladder cord suspended from the head box.

  A bottom rail is arranged at the lower end of the ladder cord, and the slats are raised and lowered by raising and lowering the bottom rail by pulling the lifting cord attached to the bottom rail into the head box and pulling it out from the head box. Yes. In a general horizontal blind, an elevating cord insertion hole is provided at the center in the front-rear direction of each slat. The elevating cord is suspended from the head box, inserted into the elevating cord insertion hole, and connected to the bottom rail. ing.

  In such a type of horizontal blind, even if the slat is completely closed, solar radiation leaks through the lifting / lowering cord insertion hole, and satisfactory shielding may not be obtained.

  In order to solve such a problem, in Patent Document 1 or 2, the lifting / lowering cord is suspended from the head box to the bottom rail along the edge in the front-rear direction of the slat.

Japanese Utility Model Publication 3-35034 Japanese Utility Model Publication No. 64-33897

  In the configurations described in Patent Documents 1 and 2, since it is not necessary to provide the lifting / lowering cord insertion hole in the slat, the problem of solar radiation leakage through this hole is solved. However, in such a configuration, the lifting cord that is tensioned when the slat is fully closed is placed outside the ladder cord in the front-rear direction, so the ladder cord is pulled by the lifting cord, A force in the front-rear direction outside is applied. The force in this direction is a force in a direction to open the slat that is in the fully closed state, and as a result, the slat is slightly opened and the shielding performance is lowered.

  The present invention has been made in view of such circumstances, and provides a horizontal blind having extremely excellent shielding properties.

According to the present invention, a plurality of first and second ladder cords that are suspended from the head box and have a plurality of wefts between a pair of warp yarns, a bottom rail disposed at a lower end of the ladder cords, and the ladder cords A plurality of slats supported by a plurality of wefts, first and second lifting cords suspended from the head box to support the bottom rail, and a lifting cord length between the head box and the bottom rail Elevating means for elevating and lowering the bottom rail by changing from the head box side, the first and second elevating cords are suspended on opposite sides in the front-rear direction across the slats, and the first ladder cord is 1 has a first connecting part through which the lifting / lowering cord is slidably inserted in the vertical direction, and is engaged with a notch provided in the slat; Dar code has a second connecting portion for slidably inserting the second lift cord in the vertical direction, having at least one characteristic of the following (1) to (2), horizontal blinds are provided.
(1) The range in which the second elevating cord can move in the front-rear direction in the second connecting portion is larger than the range in which the first elevating cord can move in the front-rear direction in the first connecting portion.
(2) The weft yarn of the first ladder cord is shorter than the weft yarn of the second ladder cord.

  In order to suppress the phenomenon that the lifting / lowering cord pulls the ladder cord and the slat opens, the inventor first tried to simply increase the size of the connecting loop that connects the lifting / lowering cord and the ladder cord. As a result, the pulling force of the lifting / lowering cord is weakened, and the phenomenon that the slat opens can be suppressed. However, when the size of the connecting loop is increased, another problem (hereinafter referred to as “lateral misalignment”) occurs in which the slat is easily displaced in the width direction. As a result of investigating the cause, the position of the slat in the width direction is held by engaging the ladder cord with the notch formed in the slat, but by increasing the size of the connecting loop, the ladder cord becomes the lifting cord. On the other hand, it has been found that it becomes easier to disengage the slat notch from the ladder cord when it becomes easier to move. Thus, it is not easy to achieve both prevention of lateral displacement and prevention of slat opening.

  The present inventor further studied in such a situation. In the first ladder cord, the second ladder cord is engaged with the notch of the slat, and in the second ladder cord, the lifting cord is suspended on the opposite side across the slat. A configuration comprising at least one of the means 1) to (2) has been reached. According to such a configuration, the first ladder cord is unlikely to be disengaged from the notch of the slat and the ladder cord, and the second ladder cord is prevented from opening the slat, thereby preventing lateral deviation. And prevention of slat opening.

Hereinafter, various embodiments of the present invention will be exemplified. The various embodiments described below can be combined with each other.
Preferably, the second ladder cord is not engaged with the notch of the slat.
Preferably, the notch has a tapered surface that extends outward in the front-rear direction of the slat.
Preferably, the first ladder cord includes a plurality of first connecting portions and has at least one of the following features (A1) to (B1) for one or a plurality of first connecting portions close to the head box. (A1) The first lifting / lowering cord is not inserted into the first connecting portion and is not connected to the first connecting portion. (B1) The first lifting / lowering cord is not inserted into the first connecting portion and is connected to the first connecting portion via the first connecting member.
Preferably, the second ladder cord includes a plurality of second connecting portions and has at least one of the following features (A2) to (B2) for one or a plurality of second connecting portions close to the head box. (A2) The second lifting / lowering cord is not inserted into the second connecting portion and is not connected to the second connecting portion. (B2) The second lifting / lowering cord is not inserted into the second connecting portion and is connected to the second connecting portion via the second connecting member.
Preferably, each of the first and second ladder cords includes a plurality of first and second connecting portions and has at least one of the following features (a) to (b). (A) In the first connecting portion closest to the head box, the first lifting / lowering cord is not inserted into the first connecting portion and is not connected to the first connecting portion, and is the second connection closest to the head box. In the part, the first lifting / lowering cord is not inserted into the first connecting part and is connected to the first connecting part via the first connecting member. (B) In the second connecting portion closest to the head box, the second lifting / lowering cord is not inserted into the second connecting portion and is not connected to the second connecting portion, and the second connecting portion closest to the head box. In the portion, the second lifting / lowering cord is not inserted into the second connecting portion and is connected to the second connecting portion via the second connecting member.

It is a front view showing the whole horizontal blind composition concerning a 1st embodiment of the present invention. It is an enlarged view of the part enclosed with the dotted line in FIG. 3A is a plan view of the slat 9 of FIG. 1, FIG. 3B is a cross-sectional view taken along line AA in FIG. 3A, and FIG. 3C is FIG. It is an enlarged view of the area | region X in a). 4 (a) to 4 (b) are front views of the first and second ladder cords 5 and 6, and FIGS. 4 (c) to 4 (d) are first views of FIGS. 4 (a) to 4 (b). FIG. 5 is a cross-sectional view showing a state in which the slat 9 is held by the second ladder cords 5 and 6 and the first and second elevating cords 13 and 14 are inserted through the connecting portions 5c and 6c. 5A and 5B are cross-sectional views passing through the first and second ladder cords 5 and 6 when the slat 9 is in a horizontal state. FIGS. 6A and 6B are cross-sectional views through the first and second ladder cords 5 and 6 when the slat 9 is in a fully closed state. FIG. 7 is a view corresponding to FIG. 2 in the horizontal blind according to the second embodiment of the present invention. FIG. 8 is a view corresponding to FIG. 2 in the horizontal blind according to the third embodiment of the present invention. FIGS. 9A to 9D are views corresponding to FIGS. 4A to 4D in the horizontal blind according to the fourth embodiment of the present invention. FIGS. 10A to 10D are views corresponding to FIGS. 4A to 4D in the horizontal blind according to the fifth embodiment of the present invention. FIGS. 11A to 11B are views corresponding to FIGS. 6A to 6B in the horizontal blind according to the fifth embodiment of the present invention.

  Hereinafter, various embodiments of the present invention will be described with reference to the drawings. The various embodiments described below can be combined with each other.

1. 1st Embodiment The horizontal blind of 1st Embodiment of this invention is demonstrated using FIGS.
First and second ladder cords 5 and 6 are suspended from the lower surface 3 a of the head box 3. Each of the ladder cords 5 and 6 includes a plurality of pairs of weft yarns 5b and 6b between a pair of warp yarns 5a and 6a. A bottom rail 7 is attached to the lower ends of the ladder cords 5 and 6. A slat 9 is supported on each pair of wefts 5b, 6b of the ladder cords 5, 6. In FIG. 1, ten slats 9 are supported, but the number of slats 9 is appropriately determined depending on the height of the blinds, the width of the slats 9, the interval between the slats 9 in each stage, and the like. In the present embodiment, the slat 9 is a relatively thick wooden slat, but the thickness and material of the slat are not particularly limited.

  From the lower surface 3 a of the head box 3, the first and second elevating cords 13 and 14 are suspended on opposite sides in the front-rear direction across the slat 9. The elevating cords 13 and 14 are suspended from the outer sides in the front-rear direction than the ladder cords 5 and 6, respectively.

  The first ladder cord 5 has a first connecting portion 5c through which the first elevating cord 13 is slidably inserted in the vertical direction, and a notch 9a provided in the slat 9 on the side where the first elevating cord 13 is suspended. Is engaged. The second ladder cord 6 has a second connecting portion 6c that allows the second elevating cord 14 to be slidably inserted in the vertical direction, and is not engaged with the notch of the slat 9. The connecting portions 5c and 6c are small rings called pico, for example. However, the connecting portions 5c and 6c do not necessarily have a ring shape, and the elevating cords 13 and 14 can be connected to the ladder cords 5 and 6 so as to be slidable in the vertical direction. Anything is acceptable. The positions and pitches at which the connecting portions 5c and 6c are provided are not particularly limited as long as the elevating cords 13 and 14 can be appropriately connected to the ladder cords 5 and 6, and the connecting portions 5c and 6c are positions corresponding to the slats 9. It may be provided in a single slat or a plurality of slats. Further, the positional relationship between the connecting portions 5c, 6c and the slats 9 is not particularly limited, and the height positions where the connecting portions 5c, 6c are provided may be either on the upper side or the lower side of the slats 9, and are as high as the slats 9. It may be.

  The connecting portions 5 c and 6 c are provided at positions slightly below the slats 9. By disposing the connecting portions 5c and 6c at such positions, it is possible to effectively prevent the lateral displacement of the slats 9 during folding. As a principle, when the slats 9 are folded, the ladder cords 5 and 6 are folded while being meandering in order from the lower stage due to the rise of the bottom rail 7, but are fixed to the lifting cords 13 and 14 that are tensioned during the folding. Since the connected portions 5c and 6c are located slightly below the slats 9, the effect of fixing the positions of the ladder cords 5 and 6 in advance occurs, so that the slats 9 are folded without being laterally displaced. To go.

  In the present embodiment, of the three ladder cords, two at both ends are the first ladder cord 5 that engages with the notch 9a, and the one at the center is the second ladder cord 6 that does not engage with the notch 9a. The second ladder cord 6 is not limited to such a configuration, and two of the two ends are not engaged with the notch 9a, and the first ladder cord 5 is engaged with the notch 9a. . Further, the number of ladder codes is not limited to three, and may be four or five. When the number of ladder codes is four, for example, two at both ends are the first ladder codes 5 and the two at the center are the second ladder codes 6, or vice versa. Further, the first ladder code 5 and the second ladder code 6 may be arranged alternately. Further, the lifting / lowering cord does not have to be disposed adjacent to all the ladder cords, and there may be a ladder cord that is not paired with the lifting / lowering cord.

  As shown in FIG. 3, the notch 9 a has a tapered surface 9 b that spreads outward in the front-rear direction of the slat 9. According to such a configuration, even when the lateral displacement of the slat in the width direction is caused by swinging the first ladder cord 5 in the width direction when the slat is folded, the weft 5b and the first ladder cord 5 are removed from the notch 9a. Even if it is difficult to disengage, for example, the weft 5b and the first ladder cord 5 are pulled back by the tapered surface 9b of the notch 9a, the weft 5b and the first ladder cord 5 are re-engaged with the notch 9a. Cheap. Thereby, the lateral shift | offset | difference of a slat is suppressed.

  As shown in FIG. 4, the size of the second connecting portion 6c is larger than that of the first connecting portion 5c. For this reason, the range in which the 2nd raising / lowering cord 14 can move in the front-back direction in the 2nd connection part 6c is larger than the range in which the 1st raising / lowering cord 13 can move in the front-back direction in the 1st connection part 5c. According to such a configuration, as will be described in detail later with reference to FIG. 6, in the fully closed state, the distance between the first lifting / lowering cord 13 and the first ladder cord 5 is the same as that of the second lifting / lowering cord 14. The distance is shorter than the distance between the second ladder cords 6. For this reason, the engagement state of the weft 5b and the first ladder cord 5 and the notch 9a is difficult to be released, and the second elevating cord 14 is weak in pulling the warp yarn 6a of the second ladder cord 6. In the closed state, a decrease in shielding property due to the ladder cord being pulled by the lifting / lowering cord is suppressed.

  Further, as shown in FIGS. 4A to 4B, the weft thread 5 b of the first ladder cord 5 is slightly shorter than the weft thread 6 b of the second ladder cord 6. According to such a configuration, as shown in FIG. 4C, the intersecting portion 5d of the pair of weft yarns 5b and the warp yarns 5a are easily held in the notches 9a. In addition, it is arbitrary to make a pair of wefts 5b cross, and you may insert the slat 9 between them, without making a pair of wefts 5b cross. Further, the weft yarn 5 b of the first ladder cord 5 may have the same length as the weft yarn 6 b of the second ladder cord 6. In this case, since the warp 5a is easily detached from the notch 9a, it is preferable to dispose the intersecting portion 5d in the notch 9a. The pair of weft yarns 6b of the second ladder cord 6 may or may not intersect with each other, but the presence of the intersecting portion 6d is preferable because the followability of the slats 9 to the movement of the weft yarn 6b is improved.

  As shown in FIG. 5, in this embodiment, the lifting / lowering cords 13 and 14 are positioned and wound by lifting / lowering code guide portions (eg, pulleys) 19 and 20 provided on the front side and the rear side of the head box 3, respectively. The drum is wound around the drums 21a and 21b. With such a configuration, by rotating the winding drums 21a and 21b, it is possible to raise and lower the bottom rail 7 by changing the lifting cord length between the head box 3 and the bottom rail 7. The winding drums 21 a and 21 b can be rotated by rotating the drive shaft 22. The method for rotating the drive shaft 22 is not particularly limited, and an operation cord is hung on a pulley fixed to the drive shaft 22 so as not to rotate, and the pulley is rotated by pulling the operation cord to rotate the drive shaft 22. The drive shaft 22 may be rotated using an electric motor. In the present invention, the lifting / lowering means is not limited to the winding drum type lifting / lowering means as shown in FIG. 5, and the lifting / lowering cord 13 inserted into the head box 3 through the lifting / lowering code guide portion 19 is connected to the head box 3. It may be a so-called direct pulling type lifting and lowering means that pulls out from another position and raises and lowers the bottom rail 7 by changing the pulling amount.

  In FIG. 5, the end on the head box side of the warp 5 a of the ladder cords 5 and 6 is attached to a suspension ring (not shown) rotated by the drive shaft 22. The suspension ring rotates within a predetermined movable range, and by this rotation, one of the warp threads 5a, 6a is pulled in the direction of the arrow X, and the other of the warp threads 5a, 6a is lowered in the direction of the arrow Y. Is tilted as shown in FIG.

  The warp threads 5a and 6a of the ladder cords 5 and 6 are located on the inner side in the front-rear direction than the lifting cords 13 and 14, and therefore, in the fully closed state as shown in FIG. The force works strongly, and the slats 9 are opened and the shielding properties are likely to be lowered. However, in this embodiment, since the size of the second connecting portion 6c is relatively large, as shown in FIG. 6B, the distance between the warp yarn 6a of the second ladder cord 6 and the second lifting / lowering cord 14 is increased. In addition, as shown in FIG. 6A, the ladder cords 5 and 6 and the slats 9 approach the first lifting / lowering cord 13 so that the ladder cords 5 and 6 receive from the lifting and lowering cords 13 and 14 outward in the front-rear direction. The force is relaxed, the opening of the slat 9 is reduced, and the shielding property is improved.

The warp yarn 6a of the second ladder cord 6 is easily moved in the width direction with respect to the second lift cord 14 by the size of the second connecting portion 6c, but the second ladder cord 6 is engaged with the notch 9a. Since there is no match, there is no problem even if the movable range in the width direction is expanded. On the other hand, since the size of the first connecting portion 5c is relatively small, the warp yarn 5a of the first ladder cord 5 has a small movable range in the width direction with respect to the first elevating cord 13, and the weft yarn 5b and the first ladder cord 5 are notched. It is difficult to release the engaged state with 9a.
With the above configuration, prevention of lateral displacement and prevention of slat opening are achieved.

The present invention can also be implemented in the following forms.
The notch 9a is preferably provided only on one side (for example, the outside of the room) of the slat 9 from the viewpoint of light shielding properties, but may be provided on both sides of the slat 9 (for example, the outside of the room and the inside of the room). In this case, the notches 9 a on both sides of the slat 9 can be engaged with the first ladder cord 5.
In the above embodiment, the notch 9a and the first lifting / lowering cord 13 are disposed on the same side of the slat 9, but the first lifting / lowering cord 13 and the notch 9a are disposed on opposite sides of the slat 9. May be.
-When multiple 1st ladder cords 5 are provided, the size of the 1st connection part 5c should just be smaller than the 2nd connection part 6c in at least 1 of them. This is because the lateral displacement of the slat 9 can be prevented if the engagement state between the first ladder cord 5 and the notch 9a is difficult to be released in at least one first ladder cord 5.
In the above embodiment, the second ladder cord 6 is not engaged with the notch 9a of the slat 9, but is provided on one side (the same side as or opposite to the second lifting cord 14) or both sides of the slat 9. You may engage with a notch.
In the above embodiment, the slats 9 are held between the pair of weft threads 5b, but each slat 9 may be supported by a single weft thread 5b.

2. Second Embodiment Next, a horizontal blind according to a second embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 7, in this embodiment, the elevating cords 13 and 14 are not inserted into the connecting portions 5 c and 6 c arranged corresponding to the uppermost slat 9, and correspond to the second slat 9. In the connecting portions 5c and 6c arranged in this manner, spiral extending members 5e and 6e are inserted into the connecting portions 5c and 6c, and the lifting cords 13 and 14 are inserted into the extending members 5e and 6e. In the third and subsequent stages, the lifting cords 13 and 14 are inserted into the connecting portions 5c and 6c as in the first embodiment. The reason for adopting such a configuration is that, in the several connecting portions 5c and 6c close to the head box 1, the lifting cords 13 and 14 particularly have a force that pulls the warp threads 5a and 6a of the ladder cords 5 and 6 outward in the front-rear direction. Since it is strong, the lifting / lowering cords 13 and 14 and the connecting portions 5c and 6c are completely separated or the lifting and lowering cords 13 and 14 and the connecting portions 5c and 6c are connected via the extension members 5e and 6e. This is to suppress the pulling of the warp yarns 5a and 6a by 14. Moreover, when the extension members 5e and 6e are used, the friction between the raising / lowering cords 13 and 14 and the connection parts 5c and 6c can be reduced, and durability of the connection parts 5c and 6c can be improved.

  As described above, the lifting / lowering cords 13 and 14 are not necessarily inserted through all the connecting portions 5c and 6c, and the lifting / lowering cords 13 and 14 and the connecting portions 5c and 6c are connected via the extending members 5e and 6e. May be. Further, the extension members 5e and 6e may be used only in any one of the connection portions 5c and 6c. Also in the connection portions 5c and 6c closest to the head box 1, the lifting cords 13 and 6e are connected via the extension members 5e and 6e. 14 may be connected to the connecting portions 5c and 6c.

3. Third Embodiment Next, a horizontal blind according to a third embodiment of the present invention will be described with reference to FIG.
In this embodiment, the connecting portions 5c and 6c are arranged slightly below the slat 9 as in the first embodiment. Further, the connecting portions 5c, 6c closest to the head box 1 are connected to the lifting / lowering cords 13, 14 via the extending members 5e, 6e. Also in such an embodiment, the effect of preventing lateral displacement of the slats 9 and the effect of improving the durability of the connecting portions 5c and 6c are obtained.

4). Fourth Embodiment Next, a horizontal blind according to a fourth embodiment of the present invention will be described with reference to FIG.
In this embodiment, the connecting portions 5 c and 6 c are arranged at the same position as the wefts 5 b and 6 b, that is, at the same position as the slats 9. With such a configuration, the lateral displacement of the slat 9 can be effectively suppressed. As a principle, when the slats 9 are folded, the ladder cords 5 and 6 are folded while being meandered in order from the lower stage by raising the bottom rail 7. Tension is applied to the lifting cords 13 and 14. When the connecting portions 5c and 6c are present at the same position as the slat 9, the connecting portions 5c and 6c are fixed without being displaced by the connecting portions 5c and 6c to which the tension of the elevating cords 13 and 14 is applied. Since there is a slat 9, the lateral displacement of the slat 9 is suppressed. In addition, only the connection part 5c may be arrange | positioned at the height of the same position as each slat 9, and the connection part 6c may be arrange | positioned a little below or the upper side of the slat 9. FIG.

5. Fifth Embodiment Next, a horizontal blind according to a fifth embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 10, in the present embodiment, the first connecting portion 5c and the second connecting portion 6c have substantially the same size, but the length of the weft thread 6b of the second ladder cord 6 is the first ladder cord. It is 1.1 times or more the length of the 5 weft 5b. L2 / L1 is, for example, 1.1 to 2, preferably 1.2 to 1.5. This is because if L2 is too large, the function of holding the slats 9 is too low.

  As shown in FIG. 11, in this embodiment, the distance between the warp yarn 6a of the second ladder cord 6 and the second lifting cord 14 does not increase, but the slat 9 held by the weft yarn 6b of the second ladder cord 6 is Since the movable range in the front-rear direction is large, the slat 9 approaches the first lifting / lowering cord 13 and the outward force in the front-rear direction received by the ladder cords 5 and 6 from the lifting / lowering cords 13 and 14 is relaxed, and the opening of the slat 9 is reduced. As a result, the shielding property is improved.

3: Head box 5: First ladder cord 6: Second ladder cord 5a, 6a: Warp yarn 5b, 6b: Weft yarn 5c, 6c: Connection portion 7: Bottom rail 9: Slat 9a: Notch 13: First lifting cord 14 : Second lifting cord

Claims (6)

A plurality of first and second ladder cords hanging from the head box and having a plurality of wefts between a pair of warp yarns;
A bottom rail disposed at the lower end of the ladder cord;
A plurality of slats supported by a plurality of weft threads of the ladder cord;
First and second lifting cords hanging from the head box and supporting the bottom rail;
Elevating means for elevating the bottom rail by changing the elevating cord length between the head box and the bottom rail from the head box side;
The first and second lifting / lowering cords are suspended on opposite sides in the front-rear direction across the slat,
The first ladder cord has a first connecting portion that allows the first elevating cord to be slidably inserted in the vertical direction, and is engaged with a notch provided in the slat,
The second ladder cord has a second connecting portion that allows the second elevating cord to be slidably inserted in the vertical direction,
A horizontal blind having at least one of the following features (1) to (2).
(1) second lift cord is movable range in the front-rear direction at the second connecting portion, the first lift cord is much larger than the movable range in the front-rear direction at a first connecting portion, the first and second connection Each part is configured by connecting both ends of the thread-like member to the warp.
(2) In a state where the slats are not supported by the weft threads of the first and second ladder cords, the weft threads of the first ladder cord are shorter than the weft threads of the second ladder cord. The horizontal blind according to claim 1, wherein the second ladder cord is not engaged with the notch of the slat. The horizontal blind according to claim 1, wherein the notch has a tapered surface that extends outward in the front-rear direction of the slat. The first ladder cord includes a plurality of first connecting portions, and has at least one of the following features (A1) to (B1) for one or more first connecting portions close to the head box. The horizontal blind according to claim 3.
(A1) The first lifting / lowering cord is not inserted into the first connecting portion and is not connected to the first connecting portion.
(B1) The first lifting / lowering cord is not inserted into the first connecting portion and is connected to the first connecting portion via the first connecting member. The second ladder cord includes a plurality of second connecting portions, and has at least one of the following features (A2) to (B2) for one or more second connecting portions close to the head box. The horizontal blind according to claim 4.
(A2) The second lifting / lowering cord is not inserted into the second connecting portion and is not connected to the second connecting portion.
(B2) The second lifting / lowering cord is not inserted into the second connecting portion and is connected to the second connecting portion via the second connecting member. Each of the first and second ladder cords includes a plurality of first and second connecting portions, and has at least one of the following features (a) to (b). Horizontal blinds described in 1.
(A) In the first connecting portion closest to the head box, the first lifting / lowering cord is not inserted into the first connecting portion and is not connected to the first connecting portion, and is the second connection closest to the head box. In the part, the first lifting / lowering cord is not inserted into the first connecting part and is connected to the first connecting part via the first connecting member.
(B) In the second connecting portion closest to the head box, the second lifting / lowering cord is not inserted into the second connecting portion and is not connected to the second connecting portion, and the second connecting portion closest to the head box. In the portion, the second lifting / lowering cord is not inserted into the second connecting portion and is connected to the second connecting portion via the second connecting member.