JP7621076B2 - BLIND - Google Patents

Description

This embodiment relates to blinds with shading material.

A conventional blind of this type is shown in the following Patent Document 1. The blind shown in Patent Document 1 includes a rotating shaft rotatably supported on a head box, a first winding drum that fits coaxially around the rotating shaft and rotates in conjunction with the rotating shaft, a lifting cord that passes through the slats and has one end engaged with the bottom rail, and the other end of the lifting cord is wound around the first winding drum, a second winding drum that fits coaxially around the rotating shaft and rotates in conjunction with the rotating shaft, and a pull-out cord that has one end engaged with the second winding drum and wound around the second winding drum, a pull-out cord that passes through the head box and has the other end hanging down outside the head box. The pull-out cord passes through a hollow operating rod that is connected to a tilting shaft that tilts the slats in the head box via a gear and can rotate the tilting shaft, and is led out from the lower end.

With this type of blind, when the pull-out cord extending from the lower end of the control rod is pulled down, the second winding drum rotates and the rotating shaft moves in tandem, causing the first winding drum to wind up the lifting cord and lift the slats. In addition, when the control rod is rotated, the tilting shaft rotates via a gear, allowing the slats to be tilted.

Japanese Patent Application Publication No. 08-232559

However, with the blinds described in Patent Document 1 mentioned above, the tilting shaft located below the lifting drum is positioned toward the front of the head box, which allows the rotation of the gears to be directly transmitted by meshing with the tilting shaft, but the tilting drum is positioned to protrude in front of the lifting drum, which creates a problem in that the front-to-rear width of the head box becomes large.

The present invention was made to solve the above-mentioned problems, and aims to provide a technology that can reduce the front-to-rear width of the head box.

In order to solve the above-mentioned problems, one aspect of the present invention is characterized in that it comprises a lifting drum that is rotatably housed in a head box and to which a lifting cord for lifting and moving a shielding material is connected so that it can be wound and unwound, a rotating drum that is rotatably housed in the head box and rotates the shielding material, and a drive shaft that is connected to the rotating drum so that it can be rotated by an operating unit, and at least a portion of the drive shaft is arranged to pass directly below the lifting drum.

According to the present invention, the front-to-rear width of the head box can be made compact.

FIG. 2 is a front view showing the blind according to the embodiment. FIG. 2 is a vertical cross-sectional view showing the internal structure of the head box. FIG. 2 is a perspective view showing the internal structure of a head box. 3 is a cross-sectional view taken along line AA shown in FIG. 2. This is a cross-sectional view corresponding to line AA in the vicinity of the lifting drum located in the center. FIG. 2 is a vertical cross-sectional view showing the internal structure of the operation unit. 3 is a cross-sectional view taken along line BB shown in FIG. 2. 3 is a cross-sectional view taken along line CC shown in FIG. 2. 4 is a cross-sectional view equivalent to line CC when the operating cord is pulled. FIG. 3 is a cross-sectional view taken along line DD shown in FIG. 2. This is a cross-sectional view corresponding to line D-D when the operating cord is pulled. 3 is a cross-sectional view taken along line E-E shown in FIG. 2. 4 is a cross-sectional view equivalent to line E-E when the operating cord is pulled. FIG. 1 is a side view showing a state in which the slats are in a lowermost position in a blind according to an embodiment of the present invention. 1 is a side view showing a state in which the operating cord is pulled and the slats are raised in the blind according to the embodiment. FIG. 1 is a side view showing a state in which the operating cord of the blind according to the embodiment is released. FIG. 1 is a side view showing a state in which the slats are tilted by rotating an operating member in the blind according to the embodiment. FIG. 13 is a cross-sectional view of the blind according to the first modified example taken along line BB. FIG. FIG. 11 is a vertical cross-sectional view of the vicinity of the lifting drum in a blind according to a second modified example. 20 is a cross-sectional view taken along line FF shown in FIG. 19.

Below, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, the present invention will be described as being applied to a horizontal blind equipped with slats as a shielding material. In this embodiment, the surface facing the room when the blind is installed will be referred to as the front, the surface facing the outside of the room as the back, the direction consisting of the front and back as the front-to-back direction, and the longitudinal direction of the blind as the left-to-right direction. In this specification and drawings, components having substantially the same functions will be given the same reference numerals to avoid redundant description.

(Overall composition)
First, the overall structure of the blind according to this embodiment will be described. Fig. 1 is a front view showing the blind according to this embodiment. In this figure, the bottom rail is lowered to the lowest position, and the slats are horizontal, i.e., the blind is shown in a fully open state. Also, in Fig. 1, only the head box and its interior are shown.

As shown in FIG. 1, the blind 1 of this embodiment includes a head box 2, an operating unit 3 provided within the head box 2, a number of slats 4, and a bottom rail 5.

The head box 2 is fixed to a window frame or the like via multiple brackets 21, and head box caps 22 are detachably attached to both sides. Inside the head box 2, there are a first drive shaft 231 and a second drive shaft 232, three lifting drums 241, three rotating drums 242 (not shown here) (see FIG. 2), a brake device 250 that slows down the rotation of the first drive shaft 231, and a stopper device 260 that restricts the rotation of the first drive shaft 231.

The operation unit 3 is provided on the right side of the head box 2 in the figure, and engages with one end of an operation member 36 that hangs down from the head box 2. When this operation member 36 is operated by an operator, the operation unit 3 rotates the first drive shaft 231 and the second drive shaft 232.

The slats 4 are supported by ladder cords 62 so that multiple slats 4 are arranged in the vertical direction between the head box 2 and the bottom rail 5. One end of the ladder cords 62 is connected to the rotating drum 242 and hangs down from the head box 2, while the other end is connected to the bottom rail 5, and the slats 4 are arranged in front and behind the slats 4 so as to sandwich them, supporting the slats 4 individually. Therefore, in response to the rotation of the rotating drum 242, the front and rear ladder cords 62 move relative to each other in the vertical direction, thereby tilting, and the slats 4 rotate to a fully closed state, horizontal (fully open), or semi-fully closed state, etc.

The bottom rail 5 is suspended and supported at the bottom end of the blind 1 by connecting one end of a lifting cord 61, the other end of which is connected to the lifting drum 241 so that it can be wound and unwound. Therefore, the lifting cord 61 moves up and down as it is wound and unwound by the lifting drum 241, and this lifting and lowering movement causes the multiple slats 4 to move up and down.

Next, the configuration of each of the drive shafts and drums mentioned above will be explained using Figures 2 to 5. Figure 2 is a vertical cross-sectional view showing the internal structure of the head box, and Figure 3 is a perspective view thereof. Figure 4 is a cross-sectional view taken along line A-A shown in Figure 2, and Figure 5 is a cross-sectional view equivalent to line A-A near the lifting drum located in the center.

As shown in Figures 2 and 3, the lift drum 241 is rotatably housed in a lift drum receiver 243 provided in the head box 2, and is connected to the first drive shaft 231 so as to be rotatable together with the first drive shaft 231 by passing through the lift drum receiver 243. A cord holder 244 is provided on the lift drum receiver 243, and the lift cord 61 hangs down from below the cord holder 244. The above configuration is the same for all three lift drums 241, but as shown in Figure 1, the lift drum 241 on the left side of the figure is arranged in the opposite direction to the other two lift drums 241 due to the storage space in the head box 2, and the lift cord 61 is also wound in the opposite direction.

One end of the first drive shaft 231 reaches the operation unit 3 and is connected to an interlocking member 324 (described later) so as to be able to rotate together with it. As a result, the three lifting drums 241 rotate in the same direction via the first drive shaft 231 in response to the rotation of the interlocking member 324. In this embodiment, the lifting drums 241 are connected to the first drive shaft 231 via the input drum 245 as shown in FIG. 4.

The rotating drum 242 is rotatably housed in the rotating drum receiver 246 attached to the lifting drum receiver 243, and is connected to the second drive shaft 232 so as to be rotatable therewith by passing through the rotating drum 242. One end of the second drive shaft 232 reaches the operation unit 3 and is connected to the output gear 341 so as to be rotatable therewith. When the operator rotates the operating member 36, the output gear 341 transmits the driving force to the second drive shaft 232, and the second drive shaft 232 rotates in response to the driving force, causing the three rotating drums 242 to rotate in the same direction.

As shown in Figures 3 and 4, in this embodiment, the second drive shaft 232 is arranged to pass directly below the lift drum 241. More specifically, the second drive shaft 232 is arranged vertically below the first drive shaft 231 so that the front-to-rear positions of the first drive shaft 231 and the second drive shaft 232 are the same, and thus the rotating drum 242 is located directly below the lift drum 241. In addition, since the rotating drum 242 is formed with a smaller diameter than the lift drum 241, the diameter range L2 of the rotating drum 242 in the front-to-rear direction shown in Figure 4 is located within the diameter range L1 of the lift drum 241 in the same direction.

By configuring it in this way, the rotating drum 242 can be positioned within the range of the lifting drum 241 in the front-to-rear direction of the head box 2, making it possible to reduce the front-to-rear width of the head box 2 compared to a case in which part or all of the rotating drum 242 is positioned outside that range.

As shown in FIG. 4, the lifting cord 61 hanging down from the lifting drum 241 at the right end in FIG. 1 in the vicinity of the operation unit 3 in the front-rear direction rearward extends vertically without substantially bending as it passes behind the rotating drum 242 and comes into contact with the rear roller 247 rotatably mounted in the rotating drum receiver 246. This is the same for the lifting drum 241 at the left end in FIG. 1. For the sake of explanation, these lifting drums are also referred to as the first lifting drum 241. On the other hand, as shown in FIG. 5, the lifting cord 61 hanging down from the lifting drum 241 at the center in FIG. 1 is routed so as to straddle the rotating drum 242 from the rear side in the front-rear direction to the front side in the front-rear direction, and passes in front of the rotating drum 242, comes into contact with the front roller 248 rotatably mounted in the rotating drum receiver 246, bends slightly, and then extends vertically. For the sake of explanation, this lifting drum is also referred to as the second lifting drum 241.

This configuration sandwiches the multiple slats 4 between the lifting cords 61 in the front-to-rear direction, realizing stable lifting and lowering operations, and since the lifting cords 61 hanging down from the first lifting drum 241 hang down from the rear of the head box 2 without bending, the generation of load can be suppressed. Furthermore, although the lifting cords 61 hanging down from the second lifting drum 241 bend more than the lifting cords 61 hanging down from the first lifting drum 241, they can be routed with less bending resistance. Therefore, the load on the lifting cords 61 can be reduced. Furthermore, since the lifting cords 61 of the second lifting drum 241 are routed so as to straddle the rotating drum 242 below, the lifting cords 61 can be routed in front of the rotating drum 242 without interfering with the drum.

In this embodiment, the second lift drum 241 is disposed between the two first lift drums 241, but it is of course also possible to dispose the first lift drum 241 between the two second lift drums 241.

(Configuration of Operation Unit 3)
Next, the configuration of the above-mentioned operation unit 3 will be described with reference to Figures 1 to 3 and 6 to 9. Figure 6 is a vertical cross-sectional view showing the internal structure of the operation unit, and Figure 7 is a cross-sectional view taken along line B-B in Figure 2. Figure 8 is a cross-sectional view taken along line C-C in Figure 2, and Figure 9 is a cross-sectional view taken along line C-C in the state in which the operation cord is pulled. For the sake of explanation, Figure 6 does not show the operation cord 361, and shows a cross-section seen from the left side.

The operation unit 3 raises and lowers the slats 4 together with the bottom rail 5 by pulling down the operation cord 361. For example, when lowering the bottom rail 5, the cord stopper 362 (see FIG. 1) to which the operation cord 361 is connected can be lightly pulled down to maintain a constant speed and lower the slats 4 together with the bottom rail 5 to the lowest position. When raising the bottom rail 5 that has been lowered to the lowest position, the cord stopper 362 can be pulled down to raise the slats 4 together with the bottom rail 5 by the amount that it is lowered. When the cord stopper 362 is released in this state, only the operation cord 361 is wound up while the bottom rail 5 remains stopped, and the bottom rail 5 can be raised again by pulling it down again after it is wound up.

As shown in Figures 2 and 3, the operation unit 3 includes a clutch mechanism for rotating the first drive shaft 231 in only one direction, which is made up of a pulley 321, a power spring 322, an adapter 323, and an interlocking member 324, etc., built into the main body cases 31a to 31c, and a tilt mechanism for rotating the second drive shaft 232, which is made up of an output gear 341 and an intermediate gear 342, etc., and one end of the operation member 36 is engaged with the intermediate gear 342 so as to be able to rotate it.

First, we will explain the various configurations related to the operating cord 361 and the configuration of the tilting mechanism.

As shown in Figures 6 and 7, the pulley 321 is supported by the fixed shaft 311 of the main body case 31a so as to be relatively rotatable, and the operation cord 361 of the operation member 36 is connected to it so as to be able to be wound and unwound. As shown in Figures 8 and 9, the power spring 322 has one end connected to the pulley 321 and the other end connected to the fixed shaft 311, and constantly applies a biasing force to the pulley 321 in the winding direction in which the operation cord 361 is wound. As a result, when the operator pulls down the operation cord 361, as shown in Figure 9, the operation cord 361 is unwound from the pulley 321 and the pulley 321 rotates, and the power spring 322 contracts in diameter in response to the rotation.

As shown in FIG. 7, the operating cord 361 is formed in a string shape, and one end is connected to the pulley 321 as described above, and the other end hangs down from the pulley 321 and is inserted into the operating member 36 and connected to the cord stopper 362 (see FIG. 1 and FIG. 14). Although the operating cord 361 is biased in the winding direction, the cord stopper 362 abuts against the lower end of the hollow operating rod 363 of the operating member 36, preventing further winding of the operating cord 361. The lower part of the operating rod 363 is expanded in diameter to form a gripping part for the operator to grip when operating the operating member 36, and the cord stopper 362 abuts against the lower end of this gripping part. On the other hand, when the cord stopper 362 is pulled down so as to be separated from the operating rod 363 and then released, the power spring 322 winds up the operating cord 361, and the cord stopper 362 and the operating rod 363 abut again.

6 and 7, the operating rod 363 of the operating member 36 is connected to the tilt input shaft 365 via the joint 364 at its upper end so as to be rotatable together with the tilt input shaft 365. The tilt input shaft 365 is rotatably supported in the head box 2, and an input gear 366, which is a so-called worm wheel, is provided at its upper end. The input gear 366 meshes with the intermediate gear 342, which is a so-called worm gear rotatably supported in the main body cases 31a and 31b. The intermediate gear 342 is located below and forward of the axis of the output gear 341, which is also a worm gear (second drive shaft 232), and meshes with the output gear 341, so that a rotational force can be transmitted to the output gear 341. Therefore, the rotation of the operating rod 363 is transmitted to the joint 364, the tilt input shaft 365, and the input gear 366, and the driving force is transmitted to the second drive shaft 232 via the intermediate gear 342 and the output gear 341.

The tilt input shaft 365 has an insertion hole 367 through which the operation cord 361 is inserted, and an inlet 368 is formed at its upper end to introduce the operation cord 361 into the insertion hole 367. The inlet 368 faces the opening formed by the main body case 31a and the main body case 31b and communicates with it, and the operation cord 361 that passes through the opening and the inlet 368 is introduced into the insertion hole 367. In this embodiment, the tilt input shaft 365 is positioned so that the inlet 368, specifically its front-to-rear width W, is located in the vertical direction at the position where the operation cord 361 hangs down from the pulley 321.

According to the above configuration, the operating cord 361 hangs down from the pulley 321, and the proximal portion 361a close to the pulley 321 extends in a substantially vertical direction and is introduced into the inlet 368. As a result, when the cord stopper 362 is pulled down, the direction in which the operating cord 361 is pulled out from the pulley 321 and the direction in which the operating cord 361 hangs down from the pulley 321 are substantially the same, so that the load on the operating cord 361 can be reduced compared to the conventional case. This is also true when the operating cord 361 is wound around the pulley 321. In addition, since the inlet 368 is located in the vertical direction at the hanging position of the operating cord 361, the operating cord 361 can be guided in a substantially vertical direction simply by routing the operating cord 361 toward the inlet 368. Furthermore, because the operating cord 361 extends in a substantially vertical direction and is introduced into the inlet 368, the tilt input shaft 365 is brought closer to the pulley 321 in the front-to-rear direction, so the amount of protrusion of the tilt input shaft 365 in front of the head box 2 can be reduced, improving the design.

In addition, in this embodiment, since the second drive shaft 232 is disposed directly below the lift drum 241, if the input gear 366 of the tilt input shaft 365 is directly meshed with the output gear 341, the inlet 368 cannot be positioned vertically at the drooping position of the operation cord 361, making it difficult to extend the operation cord 361 in a substantially vertical direction and introduce it into the inlet 368, which in turn increases the bending resistance of the operation cord 361 in the operation member 36. However, by interposing the intermediate gear 342 between the input gear 366 and the output gear 341 and positioning the axis of the intermediate gear 342 below the second drive shaft 232, the input gear 366 can be positioned vertically at the drooping position together with the inlet 368. This makes it easier to extend the operation cord 361 vertically and introduce it into the inlet 368, thereby reducing the bending resistance of the operation cord 361 in the operation member 36.

A guide surface 312 is formed on the inner wall surface of the main body case 31a above the inlet 368, and is curved to adjust the angle at which the operating cord 361 is introduced into the inlet 368. The guide surface 312 is curved to have continuity with the inner peripheral surface of the insertion hole 367 as shown in FIG. 7, so that the operating cord 361 comes into contact with the guide surface 312, allowing the cord to be inserted into the insertion hole 367 without unnecessarily bending the cord.

The tilt input shaft 365 is preferably tilted at an angle X of 35° or less with respect to the vertical so that the lower end is positioned further forward in the front-rear direction than the upper end. This makes it possible to reduce the bending angle of the operating cord 361 that passes through the joint portion 364 and is introduced into the operating rod 363. Considering the space occupied by the output gear 341 and intermediate gear 342 and the interference between the tilt input shaft 365 and the slat 4, it is more preferable that the tilt angle X be in the range of 15° to 25°, and it is particularly preferable to tilt it at an angle of about 20°. It is preferable that these angles are set appropriately depending on the width of the slat 4. For example, the above angles may be applied to slats with a width of 25 mm to 35 mm.

Next, the configuration of the clutch mechanism will be described. Figure 10 is a cross-sectional view taken along line D-D in Figure 2, and Figure 11 is an equivalent cross-sectional view taken along line D-D when the operating cord is pulled. Figure 12 is a cross-sectional view taken along line E-E in Figure 2, and Figure 13 is an equivalent cross-sectional view taken along line E-E when the operating cord is pulled.

As shown in Figures 12 and 13, the operation unit 3 includes the above-mentioned pulley 321, spiral spring 322, adapter 323, and interlocking member 324 as a clutch mechanism, as well as an intermediate shaft 325, a clutch drum 326, a clutch pin 327, a guide washer 328, and a cam drive 329.

As shown in FIG. 10, the adapter 323 is formed in a substantially disk-like shape, and the protrusion 321a of the pulley 321 fits into the center portion, connecting the adapter 323 to be rotatable together with the pulley 321. As shown in FIG. 7, one end of the intermediate shaft 325 fits into the fixed shaft 311, and as shown in FIG. 12, the other end fits into the hollow portion of the clutch drum 326 to support it so that it cannot rotate relative to the clutch drum. The clutch drum 326 is hollow cylindrical, and the clutch spring 330 fits into its peripheral wall. The clutch pin 327 is cylindrical, and transmits/receives the rotation of the pulley 321 to the interlocking member 324 by moving forward and backward in the radial direction.

The guide washer 328 is a hollow disk through which the clutch drum 326 passes and is supported so as to be capable of relative rotation. As shown in FIG. 12, the guide washer 328 has three sets of projections 328a on one side for guiding the forward and backward movement of the clutch pin 327, and two sets of projections 328b for rotating integrally with the cam drive 329.

As shown in FIG. 12, the cam drive 329 is a hollow disk-shaped member through which the clutch drum 326 penetrates and is supported so as to be capable of relative rotation. The cam drive 329 is fitted with the protrusion 323a of the adapter 323 to be engaged with the pulley 321 so as to be capable of integral rotation, and is provided with a protrusion 329b having a cam surface on one side for moving the clutch pin 327 forward and backward, and a protrusion 329c that can abut against the protrusion 328b of the guide washer 328. The cam drive 329 can rotate relative to the guide washer 328, but when the protrusion 328b abuts against the protrusion 329c, the relative rotation is restricted. As shown in FIG. 2 and FIG. 3, the first drive shaft 231 is fitted in the main body case 31c so as not to be capable of relative rotation, and is provided with an engagement portion 324a that protrudes radially inward and can be engaged with the clutch pin 327 as shown in FIG. 12.

(Slat lifting and lowering operation by clutch mechanism)
The operation of the operation unit 3 configured as above will now be described. First, the raising and lowering operation of the slats 4 by the clutch mechanism when the operation cord 361 is pulled will be briefly described with reference to Figs. 14 to 16. Fig. 14 is a side view showing the state in which the slats are at their lowest position in the blind according to this embodiment. Fig. 15 is a side view showing the state in which the operation cord is pulled and the slats are raised. Fig. 16 is a side view showing the state in which the operation cord is released.

As shown in FIG. 14, when the bottom rail 5 has already been lowered to the lowest position, the clutch pin 327 is not engaged with the engaging portion 324a of the interlocking member 324 as shown in FIG. 12. As shown in FIG. 15, when the operator pulls down the cord stopper 362 of the operating member 36, the operating cord 361 is unwound and the pulley 321 rotates. Next, the pulley 321 starts to rotate together with the cam drive 329 via the adapter 323, and the clutch pin 327 is pushed up radially outward by the cam surface of the protrusion 329b and engages with the engaging portion 324a of the interlocking member 324. At the time of this engagement, the protrusion 328b and the protrusion 329c come into contact with each other, resulting in the state shown in FIG. 13. As a result, the rotation of the pulley 321 is transmitted to the first drive shaft 231 via the interlocking member 324, and they rotate together. As the first drive shaft 231 rotates, the lifting drum 241 winds up the lifting cord 61, thereby lifting the bottom rail 5 as shown in FIG. 15.

When the operator stops pulling down the cord stopper 362, the first drive shaft 231 tries to rotate downward due to the weight of the bottom rail 5, but the stopper device 260 (see Figure 1) is activated and stops the rotation. When the operator releases the cord stopper 362 while pulling it, the pulley 321 rotates in the reverse direction due to the biasing force of the spiral spring 322, and the operating cord 361 is wound up. At this time, the protrusion 329b of the cam drive 329 no longer pushes up the clutch pin 327, but the clutch pin 327 rotates in the reverse direction together with the cam drive 329 while being sandwiched between the protrusion 328a of the guide washer 328, and is pushed down by the engaging portion 324a of the interlocking member 324, which is stopped by the stopper device 260, and the engagement is released. This release of engagement allows the pulley 321 and the interlocking member 324 to rotate relative to each other, and only the pulley 321 rotates in the reverse direction. Therefore, the reverse rotation is not transmitted to the first drive shaft 231, and the position of the raised bottom rail 5 remains unchanged.

As a result, the first drive shaft 231 is stopped by the stopper device 260, the operating cord 361 is wound around the pulley 321, and the cord stopper 362 abuts against the lower end of the operating rod 363, resulting in the state shown in FIG. 16. The operator can raise the slat 4 together with the bottom rail 5 to the highest position by repeatedly pulling down the cord stopper 362 of the operating member 36 in this manner. On the other hand, to lower the raised slat 4 and bottom rail 5, the operator pulls the cord stopper 362 and releases it when the operating cord 361 has been pulled out slightly, which releases the stopper device 260 via the first drive shaft 231, and the slat 4 and bottom rail 5 descend under their own weight. At this time, the brake device 250, which slows down the rotation of the first drive shaft 231, acts to decelerate the slat 4 and bottom rail 5 as they descend under their own weight.

(Tilting movement of slats by tilting mechanism)
Next, the tilting action of the slat 4 by the tilting mechanism when the operating cord 361 is pulled will be briefly described with reference to Fig. 17. Fig. 17 is a side view showing a state in which the slat has been tilted by rotating the operating member.

As shown in FIG. 17, when the operating rod 363 of the operating member 36 is rotated in one direction, the joint portion 364, tilt input shaft 365, and input gear 366 rotate by the same amount, and the driving force is transmitted to the intermediate gear 342 that meshes with the input gear 366. The driving force is transmitted to the output gear 341 via the intermediate gear 342, and the second drive shaft 232 connected to that gear rotates. The rotating drum 242 rotates in response to the rotation of the second drive shaft 232, and the ladder cord 62 is wound up, causing the slat 4 to tilt (rotate). On the other hand, when the operating rod 363 is rotated in the opposite direction, the second drive shaft 232 rotates in the opposite direction to the above, causing the slat 4 to tilt in the opposite direction.

According to the present embodiment described above, the second drive shaft 232 is located directly below the lift drum 241, so the rotating drum 242 can be positioned below the lift drum 241, making it possible to make the front-to-rear width of the head box 2 compact.

In addition, according to this embodiment, the proximal portion 361a of the operating cord 361 hanging down from the pulley 321, which is close to the pulley 321, can be extended in a substantially vertical direction and introduced into the operating member 36, thereby reducing the load applied to the operating cord 361 when winding and unwinding the operating cord 361.

<First Modification>
Fig. 18 is a cross-sectional view taken along line B-B of a blind according to a first modified example of this embodiment. As shown in Fig. 18, it is preferable to provide rollers 312a that can rotate relative to guide surface 312. By providing rollers 312a on guide surface 312, the contact distance (sliding distance) of operating cord 361 with guide surface 312 can be reduced, and since rollers 312a rotate when the cord slides along guide surface 312, the load on operating cord 361 can be further reduced.

<Second Modification>
Fig. 19 is a vertical cross-sectional view of the vicinity of the lifting drum in a blind according to a second modified example of this embodiment, and Fig. 20 is a cross-sectional view taken along line F-F shown in Fig. 19. As shown in Fig. 19, the rotating drum 242 is offset to the right in the drawing in the axial direction (left-right direction) compared to the rotating drum 242 shown in Fig. 2, and one end is supported by a lifting drum receiver 243 so as to be relatively rotatable.

By moving the rotating drum 242 left and right relative to the lifting drum 241 in this way, it is possible to avoid interference between the lifting cord 61 and the rotating drum 242. This increases the degree of freedom in routing the lifting cord 61, and for example, as shown in FIG. 20, the lifting cord 61 can be inserted into an insertion hole 41 provided in the center of the slat 4 in the front-to-rear direction. In this case, compared to a configuration in which multiple lifting cords 61 hang down in front and behind the slat 4, there is no need to provide front and rear rollers 247, 248, and the lifting cord 61 routed from one side to the other in the front-to-rear direction can be bent more gently, reducing the load on the cord.

In the above description, one end of the rotating drum 242 is supported by the lifting drum receiver 243 so that it can rotate relative to the lifting drum receiver 243. However, it may be supported by the rotating drum receiver 246. The rotating drum 242 may also be offset to the left side in the figure.

The present invention can be embodied in various other forms without departing from the spirit or main characteristics thereof. Therefore, the above-described embodiments are merely illustrative in all respects and should not be interpreted as limiting. The scope of the present invention is defined by the claims and is not limited in any way by the text of the specification. Furthermore, all modifications, improvements, substitutions and alterations within the scope of the claims are within the scope of the present invention.

1 Blinds 2 Head box 4 Slats (shielding material)
232 Second drive shaft (drive shaft)
241 Lifting drum 242 Rotating drum 31a to 31c Main body case (case)
312 Guide surface (guide surface)
312a roller 321 pulley 342 intermediate gear 36 operation member (operation part)
361 Operation cord 363 Operation rod (operation part)
364 Joint member 365 Tilter input shaft (operation part)
366 Input gear 367 Insertion hole 368 Inlet 61 Lifting cord

Claims (3)

a lifting drum that is rotatably accommodated in the head box and to which a lifting cord for lifting and moving the shielding material is connected so as to be capable of being wound and unwound;
A rotating drum that is rotatably accommodated in the head box and rotates the shielding material;
a drive shaft connected to the rotary drum so as to be integrally rotatable with the rotary drum and rotatably operable by an operating unit;
The drive shaft is disposed so that at least a portion of the drive shaft passes directly below the lift drum,
The rotating drum is disposed below the lifting drum,
The lifting drum and the rotating drum are provided in a plurality of parts along the extension direction of the head box ,
Among the plurality of lifting drums, a lifting cord hanging down from a first lifting drum hangs down from the rear side of the head box so as to pass behind a rotating drum located below the first lifting drum, and a lifting cord hanging down from a second lifting drum hangs down from the front side of the head box so as to pass in front of a rotating drum located below the second lifting drum,
A blind characterized in that the lifting cord hanging down from the first lifting drum or the lifting cord hanging down from the second lifting drum is routed so as to straddle the rotating drum from one side in the front-to-rear direction to the other side in the front-to-rear direction, and hangs down from the other side in the front-to-rear direction of the head box. a lifting drum that is rotatably accommodated in the head box and to which a lifting cord for lifting and moving the shielding material is connected so as to be capable of being wound and unwound;
A rotating drum that is rotatably accommodated in the head box and rotates the shielding material;
a drive shaft that is connected to the rotating drum so as to be rotatable together with the rotating drum and that can be rotated by an operating unit; and a pulley to which an operating cord is connected so as to be capable of being wound and unwound, and that can rotate the lifting drum by operating the operating cord,
The drive shaft is disposed so that at least a portion of the drive shaft passes directly below the lift drum,
The operating cord hangs down from the pulley, a portion of the operating cord adjacent to the pulley extends in a substantially vertical direction, and the operating cord is introduced into the operating portion. a lifting drum that is rotatably accommodated in the head box and to which a lifting cord for lifting and moving the shielding material is connected so as to be capable of being wound and unwound;
A rotating drum that is rotatably accommodated in the head box and rotates the shielding material;
a drive shaft that is connected to the rotary drum so as to be rotatable together with the rotary drum and can be rotated by an operation unit; and an intermediate gear that is rotatably supported in the head box and engages with an input gear formed on the operation unit to transmit the rotation of the operation unit to the drive shaft,
The drive shaft is disposed so that at least a portion of the drive shaft passes directly below the lift drum,
The blind, wherein an axis of the intermediate gear is located below an axis of the drive shaft.