JP7630239B2 - Electric Shielding Device - Google Patents

Description

The present invention relates to an electric shielding device that uses the driving force of a motor to control the elevation and lowering of a shielding material.

An electric shielding device typically uses the driving force of a motor to rotate a drive shaft, and can raise and lower the shielding material by winding or unwinding a lifting cord (including a string-like cord or a tape-like lifting tape) onto a winding drum.

In this type of motorized shielding device, a motor is disposed inside the head box, the rotation of the motor's output shaft is transmitted to a drive shaft, and the shielding material is raised and lowered based on the rotation of the drive shaft.

In addition, an encoder that detects the rotation speed and amount of rotation of the drive shaft is disposed inside the head box of the electric shading device, and based on the pulse signal output from the encoder, the encoder pulse speed and pulse count value are managed, and the motor rotation speed and amount of rotation are controlled by a control device disposed inside the head box. Through this operation, the lifting and lowering speed of the shading material is appropriately adjusted, and the stopping position of the raised and lowered shading material is controlled.

Incidentally, one type of motorized shielding device is an electric pleated screen that can be constructed by hanging a screen that can be folded vertically, for example in a zigzag shape, from a head box as a shielding material, and that can be raised and lowered electrically (see, for example, Patent Document 1).

In particular, the electric pleated screen disclosed in Patent Document 1 is made up of multiple tiers (multiple types) of shielding material connected vertically, which can be raised and lowered electrically. That is, in this electric pleated screen, the screen is made up of upper shielding material (upper screen) and lower shielding material (lower screen) made of different fabrics for the upper and lower tiers, the upper edge of the upper screen is attached to the head box and hung down, and its lower edge is attached to the middle rail, and the upper edge of the lower screen is attached to the middle rail and hung down, and its lower edge is attached to the bottom rail. The middle rail and bottom rail are then hung and supported from the head box by independent lifting cords, and the upper screen and lower screen can be raised and lowered electrically separately.

JP 2011-111763 A

As mentioned above, one type of conventional electrically-operated shading device, such as an electrically-operated pleated screen, has multiple tiers of shading material arranged vertically, each of which can be electrically raised and lowered individually.

However, in such conventional motorized shading devices, although each of the multiple tiers of shielding material connected vertically can be selected and individually raised and lowered electrically, it is not possible to simultaneously raise and lower multiple tiers of shielding material without compromising quality, i.e., to prevent damage to the fabric or lifting cord due to the upper and lower shielding materials coming close to each other.

Therefore, there is a demand for an electrically powered shielding device that allows simultaneous control of the opening and closing of multiple vertically connected shielding layers, and that can control the operation of each shielding layer with high quality.

Therefore, in consideration of the above problems, the object of the present invention is to provide an electric shielding device that allows simultaneous control of the opening and closing of each of multiple stages of shielding materials arranged vertically, and controls the operation of each shielding material with high quality.

The motorized shading device of the present invention is an motorized shading device that can electrically raise and lower each of an upper shielding material suspended from a head box and a lower shielding material suspended from an intermediate rail provided at the lower end of the upper shielding material and having a bottom rail at its lower end, and is equipped with a first winding drum that winds up or unwinds a first lifting cord for raising and lowering the upper shielding material by raising and lowering the intermediate rail, a second winding drum that winds up or unwinds a second lifting cord for raising and lowering the lower shielding material by raising and lowering the bottom rail, a first motor for rotating the first winding drum, a second motor for rotating the second winding drum, and a control device that controls the raising and lowering of each of the upper shielding material and the lower shielding material by controlling the drive of the first and second motors in response to an operation signal, and the control device controls the raising and lowering of each of the upper shielding material and the lower shielding material when each of the upper shielding material and the lower shielding material are raised and lowered simultaneously in the same direction. The device is characterized in that it is configured to control one of the upper and lower shielding materials at a predetermined lifting and lowering speed that does not cause the other to catch up, and has a means for allowing an operation signal for lifting and lowering one of the upper and lower shielding materials even when the other shielding material is in operation, and when a direction is specified by the operation signal for lifting and lowering of one of the shielding materials, if the other shielding material is operating in the same direction, controlling the one shielding material to be simultaneously operated in the direction specified by the operation signal at the predetermined lifting and lowering speed that does not cause the one shielding material to catch up with the lifting and lowering speed of the other shielding material that is operating, and when the other shielding material is operating in a different direction, controlling the one shielding material to be simultaneously operated in the direction specified by the operation signal at the lifting and lowering speed specified at the time of the operation signal or at a predetermined lifting and lowering speed, within a movable range that is specified so that the upper and lower shielding materials in operation do not come close to each other to a predetermined distance .

The present invention provides an electrically powered shielding device having multiple stages of shielding material arranged vertically, allowing simultaneous control of the opening and closing of each shielding material, thereby enabling high-quality control of the operation of each shielding material.

1A to 1C are a plan view, a front view, and a side view, respectively, showing a schematic configuration of an electric shading device according to an embodiment of the present invention. 1 is a block diagram showing a schematic configuration of a control device in an electric shading device according to an embodiment of the present invention; 4 is a flowchart showing an example of control by a control device in the motorized shading device according to one embodiment of the present invention. 1A is a side view of an electric shading device according to the present invention, which shows the operation of a plurality of shading materials when they rise simultaneously, and FIG. 1B is a side view of an electric shading device according to a comparative example. 1A is a side view of an electric shading device according to the present invention, illustrating the operation of a plurality of shading materials when they are lowered simultaneously, and FIG. 1B is a side view of an electric shading device of a comparative example. 1 is a diagram showing the relationship between the drum diameter of a winding drum for each of a plurality of shielding materials and its rotation speed in an electric shielding device according to an embodiment of the present invention. FIG. 5A and 5B are flow charts each showing an outline of control of the lifting and lowering speeds of an upper shielding material and a lower shielding material by a control device in an electric shading device according to one embodiment of the present invention. FIG. 1 is a timing diagram showing a duty ratio-based timing evaluation value between a target pulse and a pulse from an encoder in speed control by a control device in an electric shading device according to an embodiment of the present invention. 1A to 1C are schematic side views showing examples in which a control device according to the present invention is applied to an electric shading device according to another typical embodiment of the present invention.

An embodiment of an electric shading device according to the present invention will be described below with reference to the drawings. In this specification, the upper and lower sides of the front view of the electric shading device shown in FIG. 1(b) are defined as the upper direction (or upper side) and the lower direction (or lower side), respectively, and the left side of the figure is defined as the left side of the electric shading device, and the right side of the figure is defined as the right side of the electric shading device. In the example described below, the side viewed from the front view of the electric shading device shown in FIG. 1(b) is defined as the front side (or indoor side), and the opposite side is defined as the rear side (or outdoor side).

(Overall composition)
1A to 1C are plan views (top view), front views, and side views showing the schematic configuration of an electric shading device according to an embodiment of the present invention. As a representative example of the electric shading device shown in FIG. 1, an electric pleated screen is shown, in which a plurality of shading materials are arranged vertically in a row and can be raised and lowered. However, the electric shading device does not have to be limited to this as long as each of the plurality of shading materials arranged vertically in a row can be electrically raised and lowered by rotating a drive shaft. For example, the electric shading device may be a pleated screen, a honeycomb screen, a horizontal blind, a roll-up curtain, or a hybrid electric shading device in which these different types of shading materials are arranged vertically in a row.

In addition, in the embodiment of the electric pleated screen shown in Figures 1(a) to (c), an example is shown in which two types of shielding materials, an upper screen 6U as an upper shielding material and a lower screen 6L as a lower shielding material, which can be raised and lowered individually by multiple types of lifting cords 3U and 3L, are arranged vertically in a row, but the electric pleated screen may also have three or more types of shielding materials arranged in the vertical direction.

In one embodiment of the electric pleated screen shown in Figures 1(a) to (c), an upper screen 6U that can be folded in a zigzag shape is suspended from the underside of a head box 1, and the lower end of the upper screen 6U is attached to the upper surface of an intermediate rail 7U that functions as a weight member. The head box 1 is fixed to a mounting surface such as a ceiling surface via a bracket 15.

As shown in FIG. 1(c), the upper screen 6U in this example has a protruding piece 60 at the crease on the outside of the fabric that is folded in a zigzag shape, and the protruding piece 60 has a round or long hole or other insertion hole, through which the lifting cords 3U and 3L hanging down from the head box 1 are inserted. For this reason, the lifting cords 3U and 3L hang down on the back side of the upper screen 6U, and are not visible when viewed from the front as shown in FIG. 1(b), improving the aesthetics. However, in the present invention, an insertion hole may be provided in the approximate center of the front-rear direction of the upper screen 6U, and the lifting cords 3U and 3L inserted through the insertion hole may be visible when viewed from the front. Also, as shown in FIG. 1(c), a pitch retention cord 4U hangs down from the head box 1 behind the lifting cords 3U and 3L, and its lower end is attached to the intermediate rail 7U. This pitch-maintaining cord 4U has many evenly spaced circular support cords 40, through which the lifting and lowering cords 3U and 3L are inserted. When the middle rail 7U is lowered to stretch the upper screen 6U, the protruding pieces 60 are supported by each of the support cords 40 of the pitch-maintaining cord 4U, so that the folds of the upper screen 6U are maintained at approximately equal intervals.

The lower screen 6L, which can be bent in a zigzag pattern, is suspended from the underside of the intermediate rail 7U, and the lower end of the screen 6L is attached to the upper surface of the bottom rail 7L, which functions as a weight member.

As shown in FIG. 1(c), the lower screen 6L in this example is provided with a protruding piece 60 at the fold on the outside of the fabric folded in a zigzag shape, as in the upper screen 6U. The protruding piece 60 is provided with a round or long hole, through which the lifting cord 3L is inserted, which hangs down from the head box 1 and passes through the intermediate rail 7U. For this reason, the lifting cord 3L hangs down on the back side of the lower screen 6L, and is not visible from the front as shown in FIG. 1(b), improving the aesthetics. However, in the present invention, a hole may be provided in the approximate center of the front-rear direction of the lower screen 6L, and the lifting cord 3L inserted through the hole may be visible from the front. Also, as shown in FIG. 1(c), a pitch retention cord 4L hangs down from the head box 1 behind the lifting cord 3L, and its lower end is attached to the bottom rail 7L. This pitch-maintaining cord 4L has many evenly spaced circular support cords 40, through which the lifting cord 3L is inserted. When the bottom rail 7L is lowered to stretch the lower screen 6L, the protruding pieces 60 are supported by the support cords 40 of the pitch-maintaining cord 4L, so that the folds of the lower screen 6L are maintained at approximately equal intervals.

The winding drums 51U and 51L are juxtaposed in front and behind the support members 5 arranged in appropriate positions (two positions on the left and right in this example) within the head box 1 and are supported rotatably.

The upper end of the lifting cord 3U (a string-like cord in this example, but a tape-like lifting tape would also do) is attached to each winding drum 51U so that it can be wound up or unwound, and the lower end of the lifting cord 3U passes through insertion holes formed in each protruding piece 60 provided on the outside of the upper screen 6U and is attached to the intermediate rail 7U. The winding drum 51U is formed so that its diameter gradually narrows toward one side in the axial direction, and in this example, the string-like lifting cord 3U is wound in a spiral shape around the winding drum 51U in sequence.

The upper end of the lifting cord 3L (a string-like cord in this example, but a tape-like lifting tape would also do) is attached to each winding drum 51L so that it can be wound up or unwound, and the lower end of the lifting cord 3L passes through insertion holes formed in each protruding piece 60 provided on the outdoor side of the upper screen 6U, then through the intermediate rail 7U, passes through insertion holes formed in each protruding piece 60 provided on the outdoor side of the lower screen 6L, and is attached to the bottom rail 7L. The winding drum 51L is formed so that its diameter gradually narrows toward one side in the axial direction, and in this example, the string-like lifting cord 3L is wound in a spiral shape around the winding drum 51L in sequence.

A drive shaft 2U is inserted through the central axis of each winding drum 51U, so that the rotation of the drive shaft 2U is transmitted to the winding drum 51U.

Similarly, a drive shaft 2L is inserted through the central axis of each winding drum 51L, so that the rotation of the drive shaft 2L is transmitted to the winding drum 51L.

The winding drum 51U is provided with a clutch mechanism 52U as an obstacle detection and stopping device that locks the rotation of the drive shaft 2U when the descent of the intermediate rail 7U is hindered by contact with an obstacle. The winding drum 51L is also provided with a clutch mechanism 52L as an obstacle detection and stopping device that locks the rotation of the drive shaft 2L when the descent of the bottom rail 7L is hindered by contact with an obstacle.

One end of the drive shaft 2U is connected to the output shaft of the motor 9U via a drive shaft coupler 20U, and the rotation of the output shaft of the motor 9U is transmitted to the drive shaft 2U. Therefore, the drive shaft 2U is rotated by the driving force of the motor 9U, and the lifting/lowering cord 3U is wound or unwound by the winding drum 51U based on the rotation of the drive shaft 2U, making it possible to raise and lower the intermediate rail 7U, and thus to raise and lower the upper screen 6U. Note that the winding drum 51U uses the tension of the lifting/lowering cord 3U (the weight of the upper screen 6U and the intermediate rail 7U) when lowering the upper screen 6U, so the driving force is transmitted from the winding drum 51U to the drive shaft 2U via a clutch mechanism 52U, and the descent is controlled by adjusting the driving force of this drive shaft 2U.

One end of the drive shaft 2L is connected to the output shaft of the motor 9L via a drive shaft coupler 20L, and the rotation of the output shaft of the motor 9L is transmitted to the drive shaft 2L. Therefore, the drive shaft 2L is rotated by the driving force of the motor 9L, and the lifting/lowering cord 3L is wound or unwound by the winding drum 51L based on the rotation of the drive shaft 2L, making it possible to lift and lower the bottom rail 7L, and thus lift and lower the lower screen 6L. Note that the winding drum 51L uses the tension of the lifting/lowering cord 3L (the weight of the lower screen 6L and the bottom rail 7L) when lowering the lower screen 6L, so the driving force is transmitted from the winding drum 51L to the drive shaft 2L via the clutch mechanism 52L, and the descent is controlled by adjusting the driving force of this drive shaft 2L.

The drive control of each of the motors 9U and 9L is performed by a control device 10 arranged in the head box 1. A DC power supply 11 that supplies power to the motors 9U and 9L and the control device 10 is arranged in the head box 1. When the control device 10 receives an operation signal from an operation device 25 for operating the opening and closing of each shielding material (the upper screen 6U as the upper shielding material and the lower screen 6L as the lower shielding material), it performs various controls of the electric shielding device corresponding to various commands contained in the operation signal. For example, by configuring the motors 9U and 9L as DC motors, the control device 10 can control the rotation speed of the motors 9U and 9L by controlling the duty ratio of the pulse signal supplied from the control device 10 to the motors 9U and 9L. Encoders 8U and 8L are also provided in the head box 1 to detect the rotation speed and amount of rotation of each of the drive shafts 2U and 2L, and the control device 10 manages the encoder pulse speed and pulse count value based on the pulse signals output from each encoder 8U and 8L to control the rotation speed and amount of rotation of the motors 9U and 9L. Through this operation, in response to various commands included in the operation signal, the control device 10 appropriately adjusts the lifting speed of the upper screen 6U or the lower screen 6L, and controls the lifting stop position of the upper screen 6U or the lower screen 6L.

In the electric pleated screen of this embodiment configured in this way, if the intermediate rail 7U is raised to just below the head box 1 and the upper screen 6U is folded between the head box 1 and the intermediate rail 7U, the bottom rail 7L is lowered, and the lower screen 6L is shielded from the head box 1 to the desired position.

In addition, when the bottom rail 7L is lowered to its lowest limit and the intermediate rail 7U is lowered onto the bottom rail 7L, the lower screen 6L is folded between the intermediate rail 7U and the bottom rail 7L, and the upper screen 6U is shielded between the head box 1 and the intermediate rail 7U. Therefore, for example, if the upper screen 6U is made of a light-transmitting fabric and the lower screen 6L is made of a light-blocking fabric, the degree of freedom in adjusting the amount of light can be increased.

Then, by lowering the bottom rail 7L to its lowest position and positioning the middle rail 7U halfway between the head box 1 and the bottom rail 7, soft light can be let in through the upper screen 6U, which is made of a light-transmitting fabric.

When the bottom rail 7L is raised to its upper limit and opened, the bottom rail 7L is raised together with the intermediate rail 7U, and the upper screen 6U and lower screen 6L can be folded between the head box 1 and the bottom rail 7L.

(Configuration of the control device)
FIG. 2 is a block diagram showing a schematic configuration of a control device 10 in an electric shading device according to one embodiment of the present invention.

When the control device 10 receives an operation signal from the operating device 25, it performs various controls of the electric shading device corresponding to the various commands contained in the operation signal. For example, the control device 10 manages the speed of the encoder pulses from the encoders 8U, 8L and the count value of the number of pulses to control the rotation speed and amount of rotation of the motors 9U, 9L, appropriately adjusts the lifting and lowering speed of each shielding material (each screen and each bottom rail) and controls the lifting and lowering stop position of each shielding material.

As shown in FIG. 2, the control device 10 includes a microcomputer unit 101, a memory unit 102, a communication interface (IF) unit 103, motor drive units 107U and 107L, abnormality detection units 108U and 108L, and pulse detection units 109U and 109L.

The communication IF unit 103, which is illustrated comprehensively in FIG. 2, is a functional unit that performs two-way or one-way communication with the operation device 25 depending on the form of the operation device 25, receives operation signals from the operation device 25, and outputs them to the microcomputer unit 101.

For example, when the operating device 25 is configured to transmit an operating signal via short-range wireless communication, the communication IF unit 103 has a function of receiving an operating signal from the operating device 25 and outputting it to the microcomputer unit 101, enabling mutual communication between the microcomputer unit 101 and the operating device 25 and enabling the exchange of detailed commands related to operations.

In addition, when the operating device 25 is configured to transmit an operating signal by an infrared signal, the communication IF unit 103 has a function of receiving an operating signal from the operating device 25 and outputting it to the microcomputer unit 101.

In addition, when the operating device 25 is configured to transmit an operating signal by two-way or one-way wired communication, the communication IF unit 103 has a function of receiving an operating signal from the operating device 25 and outputting it to the microcomputer unit 101.

Here, the control device 10 can be a typical example of a conventional operating device, such as a wired switch for "individually" opening and closing each shielding material (upper screen 6U as upper shielding material and lower screen 6L as lower shielding material) via a wired connection, or an infrared or wireless remote controller (hereinafter referred to as a "remote control") via a wireless connection, and can receive and control operation signals from these operating devices. However, as an embodiment of the present invention, an example will be described in which the control device 10 receives and controls operation signals from an operating device 25 that can not only individually open and close each shielding material (upper screen 6U as upper shielding material and lower screen 6L as lower shielding material), but can also "simultaneously" open and close each shielding material.

For example, the operating device 25 according to the present invention can be in a form that does not allow the open/closed position of each shielding material (upper screen 6U as upper shielding material and lower screen 6L as lower shielding material) to be specified, such as a wired or wireless switch, infrared switch, multi-switch, smartphone, tablet, personal computer, zone switch, dial switch, etc. that allows the opening and closing of each shielding material to be operated individually, but can also be in the form of a multi-switch, smartphone, tablet, personal computer, zone switch, dial switch, etc. that allows the opening and closing position (shielding rate in this example) of each shielding material (upper screen 6U as upper shielding material and lower screen 6L as lower shielding material) to be specified "individually or simultaneously" and operated wired or wirelessly.

The control device 10 can therefore receive and process operation signals from the operation device 25 that allow simultaneous specification of the open/closed positions of the upper and lower shielding materials, or can receive and process operation signals in a time series from the operation device 25 that allow individual operation of the upper and lower shielding materials without specifying their open/closed positions, and can be configured to control the elevation of both the upper and lower shielding materials individually or simultaneously. Note that the type of operation signal from the operation device 25 can be determined by including an operation device ID indicating the type of the operation device 25 in the operation signal, allowing the control device 10 to perform control according to the type of operation device 25.

That is, the control device 10 is capable of receiving and processing operation signals that do not specify the opening and closing positions of each of the shielding materials (upper screen 6U as the upper shielding material and lower screen 6L as the lower shielding material), as well as operation signals that specify the opening and closing positions individually or simultaneously, and controls the opening and closing of each of the shielding materials (upper screen 6U as the upper shielding material and lower screen 6L as the lower shielding material). In particular, the control device 10 according to the present invention, which will be described in detail later with reference to FIG. 3, allows simultaneous control of the opening and closing positions of each of the shielding materials, thereby controlling the operation of each shielding material with high quality.

Motor drive units 107U and 107L are motor drivers that drive motors 9U and 9L, respectively.

The abnormality detection units 108U and 108L are functional units that detect abnormal values (one or more of overcurrent/abnormal waveform current/abnormal waveform voltage) in the motor drive units 107U and 107L, respectively, and notify the microcomputer unit 101.

The pulse detection units 109U and 109L are functional units that receive pulse signals from the encoders 8U and 8L, respectively, and notify the microcomputer unit 101.

The microcomputer unit 101 reads and executes a program previously stored in the memory unit 102, accepts operation signals received via the communication IF unit 103, and processes various commands contained in the operation signals. This allows the control device 10, which performs various controls on the electric shading device, to be configured as a computer.

The functions of the control device 10 realized by the execution of the program by the microcomputer unit 101 include a function of receiving an operation signal, discriminating various commands contained in the operation signal, and performing various controls of the corresponding electric shading device; a function of counting the presence or absence of encoder pulses and the number of encoder pulses via pulse detection units 109U, 109L which receive pulse signals from each encoder 8U, 8L, respectively, and storing and managing the count values in the memory unit 102 as appropriate; a function of storing and managing in the memory unit 102 various settings related to the set upper limit position and set lower limit position of each shielding material which can be set according to the count value of the number of encoder pulses; a function of controlling the drive of motors 9U, 9L via motor drive units 107U, 107L which drive motors 9U, 9L, respectively; and a function of monitoring abnormal values via abnormality detection units 108U, 108L which detect abnormal values (one or more of overcurrent/abnormal waveform current/abnormal waveform voltage) in the motor drive units 107U, 107L, respectively, and notifying the microcomputer unit 101 of the abnormal values.

In the electric shielding device of this embodiment, each of the motors 9L, 9U and the control device 10 are connected by a motor harness, but no physical detection switch is provided for detecting the physical upper limit position and the physical lower limit position when raising and lowering the screen, as in the conventional electric pleated screen. Even in this case, the control device 10 can detect the physical upper limit position and the physical lower limit position that define the physical lifting and lowering operation range for each of the upper screen 6U and the lower screen 6L by one or more of the following methods: determining the absolute upper and lower limit positions based on the count value of the encoder pulses obtained from the encoders 8L, 8U, detecting abnormal values (one or more of overcurrent/abnormal waveform current/abnormal waveform voltage) in the motor drive units 107L, 107U by the abnormality detection units 108L, 108U, respectively, or detecting that the input of the encoder pulses is no longer present for a predetermined period of time during operation control. The control device 10 can then perform various settings related to the set upper limit position and set lower limit position of each shielding material based on the detected physical upper limit position and physical lower limit position.

However, the control device 10 according to the present invention, which will be described in detail later with reference to FIG. 3, allows simultaneous control of the open/closed positions of each shielding material, and aims to control the operation of each shielding material with high quality, so it may be provided with a physical detection switch for detecting the upper and lower physical limit positions when raising and lowering the screen, as in the conventional case.

(Example of control by the control device)
FIG. 3 is a flowchart showing an example of control by the control device 10 in the motorized shading device according to one embodiment of the present invention.

When the control device 10 receives an operation signal for raising and lowering the upper shielding material (upper screen 6U having an intermediate rail 7U at its lower end) and the lower shielding material (lower screen 6L having a bottom rail 7L at its lower end), it determines whether the other shielding material is in operation and whether the operation signal is for raising and lowering both the upper and lower shielding materials simultaneously, and performs different control depending on the type of operation signal (whether it is an operation signal including an open/close command to raise and lower an individual shielding material, or an operation signal including an open/close command to raise and lower both shielding materials) and the operating status of the shielding material at the time the operation signal is received.

As a more specific example, as shown in FIG. 3, when the control device 10 receives an operation signal for raising and lowering one of the upper shielding material (upper screen 6U having an intermediate rail 7U at its lower end) and the lower shielding material (lower screen 6L having a bottom rail 7L at its lower end) (step S1), it first determines whether the other shielding material is moving in the same direction as the direction specified by the operation signal for the raising and lowering of the one shielding material (step S2). For example, when the direction specified by the operation signal for the raising and lowering of the upper shielding material (upper screen 6U having an intermediate rail 7U at its lower end) is upward, the control device 10 determines whether the lower shielding material (lower screen 6L having a bottom rail 7L at its lower end) is already rising.

If the other shielding material is not operating in the same direction as the direction specified by the operation signal for the lifting and lowering of the one shielding material (step S2: N), the control device 10 then determines whether the other shielding material is operating in a direction different from the direction specified by the operation signal for the lifting and lowering of the one shielding material (step S3). For example, when the direction specified by the operation signal for the lifting and lowering of the upper shielding material (upper screen 6U having an intermediate rail 7U at its lower end) is upward, the control device 10 determines whether the lower shielding material (lower screen 6L having a bottom rail 7L at its lower end) is already downward.

Then, if the other shielding material is moving in a direction different from the direction specified by the operation signal for raising and lowering the one shielding material (step S3: Y), the control device 10 controls both the upper and lower shielding materials to move in different directions at their respective raising and lowering speeds within their movable ranges (step S5).

For example, when moving to step S5 via step S3:Y, if the direction specified by the operation signal for the raising and lowering of the upper shielding material (upper screen 6U having an intermediate rail 7U at its lower end) is upward and the lower shielding material (lower screen 6L having a bottom rail 7L at its lower end) is already downward, or if the direction specified for the raising and lowering of the lower shielding material is downward and the upper shielding material is already upward, the control device 10 raises the upper shielding material at its respective lifting and lowering speeds (the lifting and lowering speeds specified at the time of each operation signal, or a predetermined lifting and lowering speed) within its movable range up to the set upper limit position, and lowers the lower shielding material at its respective lifting and lowering speeds (the lifting and lowering speeds specified at the time of each operation signal, or a predetermined lifting and lowering speed) within its movable range up to the set lower limit position. Furthermore, if the direction specified for raising and lowering the lower shielding material is downward and the upper shielding material is already in the upward movement, or if the direction specified for raising and lowering the lower shielding material is upward and the upper shielding material is already in the downward movement, the control device 10 raises and lowers the upper and lower shielding materials at their respective raising and lowering speeds (the raising and lowering speeds specified at the time of each operation signal, or the predetermined raising and lowering speeds) within a movable range in which the upper and lower shielding materials are spaced apart by a predetermined distance (a distance that allows them to come closer physically).

When the control device 10 receives an operation signal for a stop command during the raising and lowering operation of the intermediate rail 7U or bottom rail 7L, it controls to stop the operation of all shielding materials in operation, and when the raising and lowering operation of the intermediate rail 7U or bottom rail 7L reaches the set upper limit position or the set lower limit position, it controls to automatically stop the raising and lowering operation of the intermediate rail 7U or bottom rail 7L that has reached the set upper limit position or the set lower limit position, and when the intermediate rail 7U during the lowering operation approaches the stopped bottom rail 7L to a predetermined distance at which it becomes immovable, or when the bottom rail 7L during the rising operation approaches the stopped intermediate rail 7U to a predetermined distance at which it becomes immovable, it controls to stop the operation of all shielding materials.

As a variation of the transition to step S5 via step S3:Y, when the other shielding material is operating in a direction different from the direction specified by the operation signal for raising and lowering the one shielding material (step S3:Y), the control device 10 may control the other shielding material to stop operation and operate the one shielding material, or may invalidate the operation signal received for raising and lowering the one shielding material.

Next, if the other shielding material is not operating in the same direction or in a different direction to the direction specified by the operation signal for raising and lowering the one shielding material (step S3: N), the control device 10 determines whether the operation signal is for simultaneously operating both shielding materials in the same specified direction (step S4).

Then, if the operation signal does not cause both shielding materials to move simultaneously in the same specified direction (i.e., if the operation signal causes both shielding materials to move simultaneously in specified directions) (step S4: N), the control device 10 controls both the upper shielding material and the lower shielding material to move in different directions at their respective lifting and lowering speeds within their movable ranges (step S5).

For example, when moving to step S5 via step S4:N, if the direction specified by the operation signal for raising and lowering the upper shielding material (upper screen 6U having an intermediate rail 7U at its lower end) is upward, and the control device 10 also operates the lower shielding material (lower screen 6L having a bottom rail 7L at its lower end) but the specified direction is downward, it raises the upper shielding material at its respective lifting and lowering speeds (the lifting and lowering speeds specified at the time of each operation signal, or a predetermined lifting and lowering speed) within its movable range up to the set upper limit position, and lowers the lower shielding material at its respective lifting and lowering speeds (the lifting and lowering speeds specified at the time of each operation signal, or a predetermined lifting and lowering speed) within its movable range up to the set lower limit position. Furthermore, when the specified direction for raising and lowering the lower shielding material is downward, the control device 10 also operates the lower shielding material but the specified direction is upward, and raises and lowers each of the upper and lower shielding materials at their respective lifting and lowering speeds (lifting and lowering speeds specified at the time of each operation signal, or predetermined lifting and lowering speeds) within a movable range where the upper and lower shielding materials are spaced apart by a specified distance (a distance that allows them to be physically close to each other).

In this case, too, when the control device 10 receives an operation signal for a stop command during the raising and lowering operation of the intermediate rail 7U or bottom rail 7L, it controls to stop the operation of all shielding materials in operation, and when the raising and lowering operation of the intermediate rail 7U or bottom rail 7L reaches the set upper limit position or the set lower limit position, it controls to automatically stop the raising and lowering operation of the intermediate rail 7U or bottom rail 7L that has reached the set upper limit position or the set lower limit position, and when the intermediate rail 7U in the lowering operation approaches the stopped bottom rail 7L to a predetermined distance at which it becomes immovable, or when the bottom rail 7L in the rising operation approaches the stopped intermediate rail 7U to a predetermined distance at which it becomes immovable, it controls to stop the operation of all shielding materials.

On the other hand, when the upper shielding material and the lower shielding material are raised and lowered simultaneously in the same direction, the control device 10 controls them at a predetermined lifting and lowering speed at which one of the upper shielding material and the lower shielding material does not catch up with the other. More specifically, when the operation signal is for simultaneously operating both shielding materials in the same specified direction (step S4: Y), the control device 10 controls both the upper shielding material and the lower shielding material to simultaneously operate in the direction specified by the operation signal at their respective predetermined lifting and lowering speeds (preferably the same speed) at which one of the upper shielding material and the lower shielding material does not catch up with the other (step S6). In this case, too, when the control device 10 receives an operation signal for a stop command during the raising and lowering operation of the intermediate rail 7U or bottom rail 7L, it performs control to stop the operation of all shielding materials in operation, and when the raising and lowering operation of the intermediate rail 7U or bottom rail 7L reaches the set upper limit position or the set lower limit position, it performs control to automatically stop the raising and lowering operation of the intermediate rail 7U or bottom rail 7L that has reached the set upper limit position or the set lower limit position.

In addition, when the other shielding material is operating in the same direction as the direction specified by the operation signal for raising and lowering the one shielding material (step S2: Y), the control device 10 performs control to simultaneously operate the one shielding material in the direction specified by the operation signal at a predetermined raising and lowering speed (preferably the same speed as the other) that does not catch up with the raising and lowering speed of the other shielding material in operation (step S7). That is, in this case, the control device 10 determines and controls the raising and lowering speed of the one shielding material so that the two shielding materials in operation do not approach each other, i.e., at a predetermined raising and lowering speed (preferably the same speed) that does not catch up with the raising and lowering speed of the other shielding material in operation, depending on the raising and lowering speed of the other shielding material in operation. In this case, too, when the control device 10 receives an operation signal for a stop command during the raising and lowering operation of the intermediate rail 7U or bottom rail 7L, it performs control to stop the operation of all shielding materials in operation, and when the raising and lowering operation of the intermediate rail 7U or bottom rail 7L reaches the set upper limit position or the set lower limit position, it performs control to automatically stop the raising and lowering operation of the intermediate rail 7U or bottom rail 7L that has reached the set upper limit position or the set lower limit position.

(Example of operation)
Fig. 4(a) is a side view of an electric shading device according to the present invention, which shows the operation of a plurality of shielding materials when they are simultaneously raised, Fig. 4(b) is a side view of an electric shading device of a comparative example, Fig. 5(a) is a side view of an electric shading device according to the present invention, which shows the operation of a plurality of shielding materials when they are simultaneously lowered, and Fig. 5(b) is a side view of an electric shading device of a comparative example.

The control device 10 according to this embodiment performs control according to steps S6 and S7 shown in FIG. 3 described above, thereby preventing the two shielding materials from approaching each other during operation, thereby suppressing damage to the fabric and lifting cord caused by the upper and lower shielding materials catching up with each other.

For example, as shown in FIG. 4(a), when the control device 10 according to the present invention controls both the upper shielding material (upper screen 6U having an intermediate rail 7U at its lower end) and the lower shielding material (lower screen 6L having a bottom rail 7L at its lower end) to rise in the same direction at the same time (steps S6 and S7 shown in FIG. 3), the rising speed UM of the upper shielding material (i.e., intermediate rail 7U) and the rising speed LM of the lower shielding material (i.e., bottom rail 7L) are controlled to satisfy LM≦UM.

On the other hand, for example, as in the comparative example in FIG. 4(b), if the rising speed UM of the upper shielding material (i.e., middle rail 7U) and the rising speed LM of the lower shielding material (i.e., bottom rail 7L) are controlled so that LM > UM from the position of a certain upper shielding material (i.e., middle rail 7U) and lower shielding material (i.e., bottom rail 7L) shown in FIG. 4(b-1), the rise of the lower shielding material (i.e., bottom rail 7L) will catch up with the rise position of the upper shielding material (i.e., middle rail 7U), causing slack in the lifting/lowering cord 3R or adding the weight of the upper shielding material to the lifting/lowering cord 3L, which may damage the lifting/lowering cords 3R and 3L or the shielding materials themselves.

Therefore, when the control device 10 according to the present invention is used to simultaneously raise both shielding materials in the same direction, the rising speed UM of the upper shielding material and the rising speed LM of the lower shielding material are controlled to satisfy LM≦UM, thereby allowing simultaneous control and enabling each shielding material to be raised simultaneously in the same direction with high quality.

Also, as shown in FIG. 5(a), when the control device 10 according to the present invention controls both the upper shielding material (upper screen 6U having an intermediate rail 7U at its lower end) and the lower shielding material (lower screen 6L having a bottom rail 7L at its lower end) to lower in the same direction at the same time (steps S6 and S7 shown in FIG. 3), the lowering speed UM' of the upper shielding material (i.e., intermediate rail 7U) and the lowering speed LM' of the lower shielding material (i.e., bottom rail 7L) are controlled to satisfy LM' ≥ UM'.

On the other hand, for example, as in the comparative example in FIG. 5(b), if the descent speed UM' of the upper shielding material (i.e., intermediate rail 7U) and the descent speed LM' of the lower shielding material (i.e., bottom rail 7L) are controlled so that LM' < UM' from the position of a certain upper shielding material (i.e., intermediate rail 7U) and lower shielding material (i.e., bottom rail 7L) shown in FIG. 5(b-1), the descent of the upper shielding material (i.e., intermediate rail 7U) will catch up with the descent position of the lower shielding material (i.e., bottom rail 7L), causing slack in the lifting/lowering cord 3R or adding the weight of the upper shielding material to the lifting/lowering cord 3L, which may damage the lifting/lowering cords 3R and 3L or the shielding materials themselves.

Therefore, when the control device 10 according to the present invention is used to simultaneously lower both shielding materials in the same direction, the descent speed UM' of the upper shielding material and the descent speed LM' of the lower shielding material are controlled to satisfy LM' ≥ UM', allowing for simultaneous control and enabling each shielding material to be simultaneously lowered in the same direction with high quality.

In addition, in the control device 10 according to the present invention, when simultaneously controlling the opening and closing of multiple vertically connected shielding materials in the same direction, it is preferable to always keep the lifting and lowering speed of each shielding material at the same speed, which simplifies the speed control in the control device 10.

In addition, the control of the lifting speed of each of the upper shielding material (i.e., the intermediate rail 7U) and the lower shielding material (i.e., the bottom rail 7L) in the control device 10 according to the present invention can be easily controlled by the relationship between the drum diameters d1, d2 of the winding drums 51U, 51L and their rotational speeds (i.e., the rotational speeds of the drive shafts) n1, n2. Figure 6 is a diagram showing the relationship between the drum diameters d1, d2 of the winding drums 51U, 51L for each of the multiple shielding materials in an electric shielding device according to one embodiment of the present invention and their rotational speeds n1, n2. For example, when the lifting and lowering speeds of the upper shielding material (i.e., intermediate rail 7U) and the lower shielding material (i.e., bottom rail 7L) are to be the same, it is sufficient to set them so that d1:d2=n1:n2 as shown in FIG. 6, and even if the drum diameters d1=d2 or d1≠d2, the lifting and lowering speeds of the upper shielding material (i.e., intermediate rail 7U) and the lower shielding material (i.e., bottom rail 7L) can be the same, and therefore they can be controlled to satisfy the above-mentioned ascending speed LM≦UM and the descending speed LM'≧UM'. In addition, since each winding drum 51U, 51L is formed so that the diameter gradually becomes thinner toward one side in the axial direction, it does not have a constant drum diameter strictly speaking, but the drum diameters d1, d2 shown in FIG. 6 are the average diameters of each winding drum 51U, 51L, and by determining the rotation speeds n1, n2 based on these drum diameters d1, d2, it is possible to handle it with an error of 10% or less within the lifting and lowering range of each shielding material. For this reason, in this specification, "the same speed" with respect to the lifting and lowering speed means a speed that can be considered to be the same with an error of 10% or less.

(Speed Control)
In order to make the lifting and lowering speeds of the shielding materials "uniform," it is preferable to control the lifting and lowering of each shielding material at an "approximately constant speed (error 10% or less)" within the lifting range from the upper limit position to the lower limit position of each shielding material. Here, with reference to Figs. 7 and 8, an example of controlling the lifting and lowering of each shielding material at an approximately constant speed (error 10% or less) within the lifting range from the upper limit position to the lower limit position of each shielding material for the control device 10 disposed in the motorized shading device of the embodiment shown in Fig. 1 will be described.

Figures 7(a) and (b) are flow charts each showing an outline of the control of the lifting and lowering speed of the upper and lower shielding materials by the control device in an electric shading device according to one embodiment of the present invention. Also, Figure 8 is a timing diagram showing a timing evaluation value based on the duty ratio between the target pulse and the pulse from the encoder for the speed control by the control device 10 in an electric shading device according to one embodiment of the present invention.

First, as shown in FIG. 7(a), when the control device 10 starts controlling the lifting and lowering speed of the upper shielding material (upper screen) 6U, it compares the pulse width Wtp of the target pulse TP for the lifting and lowering speed based on the rotation speed of the drive shaft 2U with the duty ratio of the pulse width Wep of the pulse EP from the encoder 8U to determine whether the pulse EP from the encoder 8U is faster than the target pulse TP for the lifting and lowering speed (step S1). Note that in FIG. 8, the pulse width Wtp of the target pulse TP for the lifting and lowering speed is normalized to 1.0, and the increase or decrease in the pulse width Wep of the pulse EP from the encoder 8U relative to this normalized pulse width Wtp is shown.

If the pulse EP from the encoder 8U is faster than the target pulse TP for the lifting/lowering speed (step S1: Y), the control device 10 outputs a pulse with a duty ratio to the motor 9U to reduce the rotational speed of the drive shaft 2U (step S2). For example, at a certain time t2 shown in FIG. 8, the pulse EP from the encoder 8U is in a timing lead state relative to the target pulse TP for the lifting/lowering speed, and in this case, the control device 10 reduces the rotational speed of the drive shaft 2U.

On the other hand, if the pulse EP from the encoder is not faster than the target pulse TP for the lifting/lowering speed (step S1: N), the control device 10 outputs a pulse with a duty ratio for increasing the rotational speed of the drive shaft 2U to the motor 9U (step S3). For example, at a certain time t1 shown in FIG. 8, the pulse EP from the encoder 8U is delayed in timing relative to the target pulse TP for the lifting/lowering speed, and in this case, the control device 10 increases the rotational speed of the drive shaft 2U.

The control device 10 then repeats steps S1 to S3, so that, for example, at a certain time t3 shown in FIG. 8, the pulse EP from the encoder 8U is synchronized with the target pulse TP for the lifting speed, making it possible to maintain the lifting speed at a substantially constant speed. Furthermore, by using pulse width modulation (PWM) control in performing this type of speed control, the lifting speed can be maintained at a substantially constant speed and also contributes to quieting the motor noise itself.

The same applies to the control of the lifting and lowering speed of the lower shielding material (lower screen) 6L. That is, as shown in FIG. 7(b), when the control device 10 starts to control the lifting and lowering speed of the lower shielding material (lower screen) 6L, the control device 10 compares the pulse width Wtp of the target pulse TP for the lifting and lowering speed based on the rotation speed of the drive shaft 2L with the duty ratio of the pulse width Wep of the pulse EP from the encoder 8L to determine whether the pulse EP from the encoder 8L is faster than the target pulse TP for the lifting and lowering speed (step S1').

If the pulse EP from the encoder 8L is faster than the target pulse TP for the lifting/lowering speed (step S1': Y), the control device 10 outputs a pulse with a duty ratio to the motor 9L to reduce the rotational speed of the drive shaft 2L (step S2'). In this case as well, as shown in FIG. 8, at a certain time t2, the pulse EP from the encoder 8L is ahead of the target pulse TP for the lifting/lowering speed in terms of timing, and in this case, the control device 10 reduces the rotational speed of the drive shaft 2L.

On the other hand, if the pulse EP from the encoder is not faster than the target pulse TP for the lifting/lowering speed (step S1': N), the control device 10 outputs a pulse with a duty ratio to the motor 9L to increase the rotational speed of the drive shaft 2L (step S3'). In this case as well, as shown in FIG. 8, at a certain time t1, the pulse EP from the encoder 8L is delayed in terms of timing relative to the target pulse TP for the lifting/lowering speed, and in this case, the control device 10 increases the rotational speed of the drive shaft 2L.

The control device 10 then repeats steps S1' to S3', so that, for example, at a certain time t3 shown in FIG. 8, the pulse EP from the encoder 8L is synchronized with the target pulse TP for the lifting speed, making it possible to maintain the lifting speed at a substantially constant speed. Furthermore, by using pulse width modulation (PWM) control in performing this type of speed control, the lifting speed can be maintained at a substantially constant speed and also contributes to quieting the motor noise itself.

Here, in order to make the upper and lower shielding materials move at the same speed, encoders 8U and 8L with the same resolution are used for each of the upper and lower shielding materials, and the control device 10 uses the encoders 8U and 8L with the same resolution to control the lifting and lowering of each of the upper and lower shielding materials with the same logic, which is advantageous for achieving high accuracy. Therefore, the motorized shielding device of the present invention allows simultaneous control of the opening and closing of each of the multiple stages of shielding materials connected in the vertical direction, and can control the operation of each shielding material with high quality.

The present invention has been described above using examples of specific embodiments, but the present invention is not limited to the above-mentioned embodiments, and various modifications are possible without departing from the technical concept thereof.

For example, the motorized shading device is not limited to the motorized pleated screen described above, but can also be applied to other types of motorized shading devices, such as a honeycomb screen, which is a type of such screen, horizontal blinds, pull-up curtains, or a hybrid configuration in which these different types of shading materials are combined and arranged vertically in a row (for example, the upper shading material is a pull-up curtain type shading material and the lower shading material is a pleated screen type shading material).

Typical examples of other motorized shading devices with vertically connected shading materials are shown in Figures 9(a) to (c), respectively. Figures 9(a) to (c) are schematic side views showing examples in which a control device according to the present invention is applied to motorized shading devices according to other typical embodiments of the present invention. Note that components similar to those in the above-mentioned embodiment are given the same reference numbers.

First, the motorized shielding device shown in FIG. 9(a) is an electric honeycomb screen that can raise and lower the upper shielding material (upper screen 6U with a honeycomb shape in side view with an intermediate rail 7U at the lower end) suspended from the head box 1 and the lower shielding material (lower screen 6L with a honeycomb shape in side view with a bottom rail 7L at the lower end) suspended from the intermediate rail 7U. The winding drums 51U and 51L shown in FIG. 9(a) raise and lower the upper screen 6U and the lower screen 6L by winding or unwinding the upper ends of the lifting and lowering cords 3U and 3L, as in the embodiment shown in FIG. 1. Note that insertion holes are provided in the joint pieces 60' that form each honeycomb shape in the upper screen 6U, and the lifting and lowering cords 3U and 3L are inserted into these insertion holes, and the lower ends of the lifting and lowering cords 3U are attached to the intermediate rail 7U. The lifting cord 3L passes through the intermediate rail 7U, is inserted into a through hole provided in the joint piece 60' that forms each honeycomb shape in the lower screen 6L, and is attached to the bottom rail 7L. Encoders 8U, 8L and motors 9U, 9L are arranged in the head box 1 (not shown). A DC power source 11 (not shown) and a control device 10 similar to that shown in FIG. 2 are also arranged in the head box 1. Therefore, the control of the control device 10 according to the present invention can be applied to the electric honeycomb screen shown in FIG. 9(a).

The motorized shading device shown in FIG. 9(b) is a motorized horizontal blind that can raise and lower an upper shading material (e.g., a group of fabric slats 6U' made of light-transmitting fabric with an intermediate rail 7U at the lower end) supported by a ladder cord 12U suspended from a head box 1, and a lower shading material (e.g., a group of light-blocking aluminum slats 6L' with a bottom rail 7L at the lower end) supported by a ladder cord 12L suspended from the head box 1 and passing through the intermediate rail 7U. The winding drums 51U and 51L shown in FIG. 9(b) raise and lower the group of fabric slats 6U' and the group of aluminum slats 6L' by winding or unwinding the upper ends of the lifting and lowering cords 3U and 3L, as in the embodiment shown in FIG. 1. An insertion hole is provided in the approximate center of the front-rear direction of the group of fabric slats 6U', and the lifting and lowering cords 3U and 3L are inserted through the insertion hole, and the lower end of the lifting and lowering cord 3U is attached to the intermediate rail 7U. The lifting cord 3L passes through the intermediate rail 7U, is inserted into a through hole provided in the approximately center of the aluminum slat group 6L' in the front-rear direction, and is attached to the bottom rail 7L. The fabric slat group 6U' and the aluminum slat group 6L' can be rotated by the relative movement of the warps of the ladder cords 12U and 12L, respectively, but the mechanism is not described here. Encoders 8U and 8L and motors 9U and 9L are arranged in the head box 1 (not shown). A DC power supply 11 (not shown) and a control device 10 similar to that shown in FIG. 2 are arranged in the head box 1. Therefore, the control of the control device 10 according to the present invention can be applied to the motorized horizontal blind shown in FIG. 9(b).

As shown in FIG. 9(c), the upper shielding material is a group of fabric slats 6U' made of light-transmitting fabric with an intermediate rail 7U at the lower end, and the lower shielding material is a lower screen 6L with a bottom rail 7L at the lower end that is zigzag-shaped (or honeycomb-shaped) in side view. A control device 10 similar to that shown in FIG. 2 may be disposed in this hybrid-configuration motorized shielding device. Other hybrid-configuration motorized shielding devices (not shown) may be configured, for example, with a roll-up curtain-type shielding material for the upper shielding material and a pleated screen-type shielding material for the lower shielding material. The control of the control device 10 according to the present invention can be applied to these hybrid-configuration motorized shielding devices.

Therefore, the motorized shading device according to the present invention is not limited to the above-described embodiment examples, but is limited only by the claims.

The present invention provides an electrically powered shading device having multiple tiers of shielding materials arranged vertically, allowing simultaneous control of the opening and closing of each shielding material, and enabling high-quality control of the operation of each shielding material, making it useful for applications as an electrically powered shading device.

1 Head box 2U, 2L Drive shaft 3U Lifting cord for upper screen 3L Lifting cord for lower screen 5 Support member 6U Upper shielding material (upper screen)
6L Lower shielding material (lower screen)
7U intermediate rail 7L bottom rail 8U, 8L encoder 9U, 9L motor 10 control device 11 DC power supply 20U, 20L drive shaft coupler 25 operation device 101 microcomputer section 102 memory section 103 communication interface (IF) section 107U, 107L motor drive section 108U, 108L abnormality detection section 109U, 109L pulse detection section

Claims (1)

An electric shielding device that electrically raises and lowers an upper shielding material suspended from a head box and a lower shielding material suspended from an intermediate rail provided at the lower end of the upper shielding material and having a bottom rail at its lower end,
a first winding drum that winds up or unwinds a first lifting cord for lifting and lowering the upper shielding material by lifting and lowering the intermediate rail;
a second winding drum that winds up or unwinds a second lifting cord for lifting and lowering the lower shielding material by lifting and lowering the bottom rail;
a first motor for rotating the first winding drum;
a second motor for rotating the second winding drum;
a control device that controls the lifting and lowering of each of the upper shielding material and the lower shielding material by controlling the driving of the first and second motors in response to an operation signal;
The control device is configured to control the upper shielding material and the lower shielding material at a predetermined lifting and lowering speed at which one of the upper shielding material and the lower shielding material does not catch up with the other when the upper shielding material and the lower shielding material are simultaneously lifted and lowered in the same direction, to allow an operation signal for lifting and lowering one of the upper shielding material and the lower shielding material even if the other shielding material is in operation, and to control the other shielding material in operation when the other shielding material is in operation in the same direction when a direction is specified by an operation signal for lifting and lowering the one shielding material. and when the other shielding material is operating in a different direction, control means for simultaneously operating one of the shielding materials in the direction specified by the operation signal at a lifting and lowering speed specified at the time of the operation signal or a predetermined lifting and lowering speed, within a movable range that is determined so that the upper and lower shielding materials in operation do not come close to each other to a predetermined distance .