Overhead Door

Abstract

To provide an overhead door capable of easily dealing with various shapes of guide rails of a door panel.SOLUTION: An overhead door 1 in which a door panel 2 having a plurality of panels 21 connected so as to be bendable is raised / lowered to be opened / closed comprises: a winding shaft 5 to which a wire winding drum 4 for winding a wire 3 connected to the door panel 2 is secured; a sprocket 6 secured to the winding shaft 5; a driven sprocket 7 disposed below the sprocket 6 and rotatable; and a rotatable chain 8 stretched to the sprocket 6 and the driven sprocket 7. A plurality of bendable weights 9 for applying a pressing force of a winding direction of the wire 3 to the winding shaft 5 are attached to the chain 8, and as the door panel 2 is raised / lowered, the weights 9 pass through the sprocket 6 and the driven sprocket 7 to change the pressing force.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an overhead door that raises and lowers a door panel formed by flexibly connecting a plurality of panels to an open state and a closed state.

Background Art

[0002] Conventional overhead doors have a door panel formed by flexibly connecting a plurality of panels that can be raised and lowered between a closed state and an open state, and as the door panel rises from the closed state to the open state, the effective weight of the door panel gradually becomes lighter, and as it descends from the open state to the closed state, the effective weight of the door panel gradually becomes heavier. They are provided with a weight chain that applies an upward biasing force to the door panel. As the door panel rises toward the open state, the entire weight chain is lowered to reduce the effective weight, and as it descends toward the closed state, the entire weight chain is raised to increase the effective weight (see, for example, Patent Document 1). There is also a mechanism provided in an opening and closing body device that performs the opening and closing operation of the door panel by moving along a pair of left and right guide rails including a vertical rail portion and a horizontal rail portion. The mechanism includes a balance mechanism that generates a tensile force to resist the downward movement due to the weight of the door panel body. A weight that generates the tensile force by a vertical load is provided, and the entire weight is lowered along a weight guide rail according to the opening and closing operation of the door panel body to reduce the vertical load, and is raised to increase the vertical load (see, for example, Patent Document 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, conventional technology involves lowering or raising the entire weight to change the biasing force acting vertically upward on the door panel, which presents a problem in that it is difficult to accommodate various shapes of guide rails that guide the door panel. In the technology described in Patent Document 1, the effective weight of the door panel is changed by raising and lowering the entire weight chain that acts as a counterweight. This presents a problem in that the effective weight of the door panel changes at the point where the door panel moves vertically along the guide rail. Furthermore, in the technology described in Patent Document 2, the entire counterweight is raised and lowered along the weight guide rail in accordance with the opening and closing operation of the door panel body to change the vertical load. This presents a problem in that if the shape of the door panel's guide rail is changed, the shape of the weight guide rail must also be changed accordingly.

[0005] The present invention aims to solve these problems and provides an overhead door that can easily accommodate various shapes of guide rails on door panels. [Means for solving the problem]

[0006] Therefore, the present invention relates to an overhead door that raises and lowers a door panel, which is made up of multiple panels connected in a flexible manner, to open and close, comprising: a rotating shaft to which a drum for winding a wire connected to the door panel is fixed; a first sprocket fixed to the rotating shaft; a second sprocket positioned below the first sprocket and rotatable; and a rotatable chain stretched between the first sprocket and the second sprocket, wherein the chain has a plurality of flexible weights attached to it that apply a biasing force to the rotating shaft in the direction of winding up the wire, and as the door panel is raised and lowered, the weights The front Note the second sprocket bottom It is characterized by passing through and changing the biasing force. [Effects of the Invention]

[0007] This invention offers the advantage of easily accommodating various shapes of door panel guide rails. [Brief explanation of the drawing]

[0008] [Figure 1] Perspective view of the overhead door in the embodiment. [Figure 2] Diagram illustrating the closed state of the overhead door in the embodiment. [Figure 3] Diagram illustrating the overhead door in the raised position in the embodiment. [Figure 4] Diagram illustrating the open state of the overhead door in the embodiment. [Figure 5] Diagram illustrating the position of weights in a modified example. [Figure 6] Diagram illustrating the position of the door panel and weight in the embodiment. [Figure 7] Diagram illustrating the case where the overhead door moves up and down in a nearly vertical direction. [Figure 8] Diagram illustrating the shape of the guide rail [Modes for carrying out the invention]

[0009] Hereinafter, an embodiment of the overhead door according to the present invention will be described with reference to the drawings. [Examples]

[0010] Figure 1 is a perspective view of the overhead door in the embodiment. In Figure 1, the overhead door 1 is configured to open and close by raising and lowering a door panel, which is made up of multiple panels that are flexibly connected. It comprises a door panel 2, wires 3 (3a, 3b), wire winding drums 4 (4a, 4b), winding shaft 5, sprocket 6, driven sprocket 7, chain 8, weight 9, residual weight 10, and guide rails 11 (11a, 11b).

[0011] The door panel 2 is formed by connecting panel 21, which is a plurality of plate-shaped members in a substantially rectangular shape, vertically bendably with a connecting part 22 such as a hinge. Rotatable rollers 23 are attached to both side portions of each panel 21 via connecting members such as hinges, and are configured to be movable along the guide rails 11 (11a, 11b) in the vertical direction indicated by arrow A and the direction indicated by arrow B (for example, the horizontal direction) in the figure. When it rises, it becomes an open state, and when it descends, it becomes a closed state. Note that when the door panel 2 is in the closed state, the whole of it is disposed below the wall portion P, closing the space between the wall portion P and the installation surface. When it is in the open state, the lower end portion is disposed at substantially the same position as the lower end portion of the wall portion P, opening the space between the wall portion P and the installation surface.

[0012] One end of the wire 3 (3a, 3b) is connected via a connecting member to a predetermined portion near the lower end of the door panel 2, and the other end is connected to the wire winding drum 4 (4a, 4b). This wire 3 (3a, 3b) is disposed at both left and right end portions of the door panel 2, and the wire 3a is connected to the wire winding drum 4a, and the wire 3b is connected to the wire winding drum 4b. When the door panel 2 rises and moves, the wire 3 (3a, 3b) is wound by the wire winding drum 4 (4a, 4b). Also, when the door panel 2 descends and moves, the wire 3 (3a, 3b) that has been wound by the wire winding drum 4 (4a, 4b) is fed out.

[0013] [[ID=I2]]The wire winding drums 4 (4a, 4b) are disposed corresponding to both left and right end portions of the door panel 2, and wind the wires 3 (3a, 3b) disposed at both left and right end portions of the door panel 2 respectively. This wire winding drum 4 (4a, 4b) is, for example, cylindrical.

[0014] The winding shaft 5 is fixed with the wire winding drums 4 (4a, 4b) and serves as the rotation axis of the wire winding drums 4 (4a, 4b). Therefore, the winding shaft 5 rotates together with the wire winding drums 4 (4a, 4b).

[0015] The sprocket 6 as the first sprocket is fixedly attached to one end of the take-up shaft 5 and rotates together with the wire take-up drum 4 (4a, 4b) and the take-up shaft 5. The sprocket 6 transmits the rotation of the take-up shaft 5 to the chain 8 and transmits the tensile force of the chain 8 to the take-up shaft 5.

[0016] The driven sprocket 7 as the second sprocket is arranged below the sprocket 6 and is provided rotatably, and rotates following the movement of the engaged chain 8.

[0017] The chain 8 is, for example, a roller chain, and is stretched so as to engage with the sprocket 6 and the driven sprocket 7, and is a rotatable endless chain. This chain 8 rotates and moves by the take-up shaft 5 and the sprocket 6 that rotate along with the opening and closing movement of the door panel 2. A plurality of bendable weights 9 that apply a biasing force in the direction of winding up the wire 3 with respect to the take-up shaft 5 as the rotation axis are attached to the chain 8.

[0018] The weight 9 as the first weight serves as a weight attached to a part of the chain 8, and generates the biasing force when the door panel 2 is opened and closed by a vertical load. The weight 9 is attached so that a plurality of weights are continuous on both sides in the rotation direction of the chain 8. Since the weight 9 is attached to both sides of the chain 8 in this way, even the part of the chain 8 to which the weight 9 is attached can engage with the driven sprocket 7. Further, since the weight 9 is composed of a plurality of separated bendable weights, the shape can be changed along with the movement of the chain 8. In this embodiment, the entire weight 9 can pass through the driven sprocket 7 while changing its shape. In this embodiment, the shape of each weight of the weight 9 is a columnar shape, but it is not limited thereto, and it may be a cube shape, a rectangular parallelepiped shape, a spherical shape, or the like as long as it does not interfere with the rotation of the chain 8.

[0019] The residual weight 10, acting as a second weight, is attached to a different part of the chain 8 from the part to which weight 9 is attached, and serves as a supplementary weight to weight 9. The residual weight 10 moves up and down between the sprocket 6 and the driven sprocket 7, and is attached to the portion of the chain 8 that does not engage with the sprocket 6 and the driven sprocket 7 when the door panel 2 is raised or lowered. Therefore, since the residual weight 10 does not pass through the sprocket 6 and the driven sprocket 7, it may be a bendable weight, but it can also be made of a non-bendable weight. In this embodiment, in order to simplify the configuration, the residual weight 10 will be described as being made of a non-bendable weight. Furthermore, the residual weight 10 is designed not to interfere with the engagement between the portion of the chain 8 to which the weight 9 is attached and the sprocket 6 and the driven sprocket 7.

[0020] The guide rails 11 (11a, 11b) have a roughly C-shaped cross-section with an opening on the inside and guide the door panel 2. A pair of guide rails 11a and 11b are arranged corresponding to the left and right sides of the door panel 2. The grooves of the guide rails 11a and 11b engage with rotatable rollers 23 attached to both sides of the door panel 2 to support the door panel 2 so that it can move, and also guide the moving door panel 2. Furthermore, the guide rail 11 (11a, 11b) includes a first guide rail 111 (111a, 111b) that guides the door panel 2 in the vertical direction, and a second guide rail 112 (112a, 112b) that extends at a predetermined angle with respect to the extension of the first guide rail 111 (111a, 111b) and guides the door panel 2. The first guide rail 111 (111a, 111b) and the second guide rail 112 (112a, 112b) are continuous at a curved R section 113 (113a, 113b).

[0021] Accordingly, the door panel 2 is guided by the first guide rail 111 (111a, 111b) and the second guide rail 112 (112a, 112b) to rise and open, and is guided by the second guide rail 112 (112a, 112b) and the first guide rail 111 (111a, 111b) to descend and close. In Figure 1, the angle formed by the extensions of the first guide rail 111 (111a, 111b) and the second guide rail 112 (112a, 112b) is described as being slightly less than 90 degrees. However, it is not limited to this; it may be 90 degrees, or less than 90 degrees, or greater than 90 degrees, and various shapes of guide rails 11 (11a, 11b) are possible.

[0022] In this embodiment, the overhead door 1 has a sprocket 6 fixed to a winding shaft 5, a driven sprocket 7 rotatably positioned below the sprocket 6, and an endless chain 8 with a weight 9 attached is rotatably stretched between the sprocket 6 and the driven sprocket 7.

[0023] Now, let's discuss weight 9. As shown in Figure 1, the weight 9 is provided on the chain 8 with multiple weights in a continuous arrangement. The positional relationship between the weight 9 and the door panel 2 is such that if D1 is the distance between the roller 23 at the upper end of the door panel 2 and the starting point of the second guide rail 112 (112a) (midpoint of the R section 113 (113a)), and D2 is the distance between the lower end of the weight 9 and the lowest part of the driven sprocket 7, then D1 and D2 are approximately equal.

[0024] In this way, when the closed door panel 2 is raised until its upper end reaches the starting point of the second guide rail 112 (112a, 112b), the entire weight 9 descends in the rotational direction indicated by arrow C in the figure, and the lower end (tip) of the weight 9 is never positioned above the lowest part of the driven sprocket 7. Therefore, the biasing force acting vertically upward on the door panel 2 does not change until the upper end of the door panel 2 reaches the starting point of the second guide rail 112 (112a, 112b).

[0025] As the door panel 2 is raised further, the tip of the weight 9, indicated by arrow C in the diagram, changes from descending to ascending, and is positioned above the lowest part of the driven sprocket 7. As a result, the biasing force acting vertically upward on the door panel 2 gradually decreases. Note that the intervals D1 and D2 can be set as appropriate to match the shape of the guide rail 11.

[0026] Next, we will explain the weights of weight 9 and residual weight 10. If W1 is the vertical weight (along the first guide rail 111) of the door panel 2 when it is closed, and W2 is the vertical weight (along the first guide rail 111) of the door panel 2 when it is open, then the total weight MW of the weight 9 is (W1-W2) / 2. Furthermore, if L is the distance that the door panel 2 travels along the second guide rail 112 from the midpoint of the R section 113, and Pt is the distance (spacing) between each weight of the weight 9, then the number of weights in the weight 9 is L / Pt, and the weight of each weight in the weight 9 is basically ((W1-W2) / 2)÷(L / Pt). It is better to set the individual weights of the weight 9 appropriately according to the weight relationship with the panel 21.

[0027] Furthermore, the weight SW of the residual weight 10 is the sum of the total weight MW of weight 9 and W2, which is (W1 + W2) / 2. As a result, when the door panel 2 is in the open position, the residual weight 10 can apply a biasing force corresponding to the weight W2 to the door panel 2 in the vertically upward direction, thereby maintaining the open position of the door panel 2. The weights of weight 9 and residual weight 10 can be appropriately set according to the weight of the door panel 2 and the shape of the guide rail 11.

[0028] The operation of the above-described configuration will be explained based on Figures 1 to 4. Figure 2 is an explanatory diagram of the overhead door in the closed state in the embodiment, Figure 3 is an explanatory diagram of the overhead door in the raised state in the embodiment, and Figure 4 is an explanatory diagram of the overhead door in the open state in the embodiment. Figures 2(a), 3(a), and 4(a) are schematic side views of the door panel and guide rail, etc., and Figures 2(b), 3(b), and 4(b) are schematic side views of the chain and weight, etc.

[0029] As shown in Figure 2(a), when the door panel 2 is closed, the entire door panel 2 is guided by the first guide rail 111 of the guide rail 11 and is perpendicular to the horizontal mounting surface, with the lower end of the door panel 2 positioned on the mounting surface and the upper end positioned approximately at the same position as the lower end of the wall P. At this time, as shown in Figure 2(b), all the weights 9 and residual weights 10 are positioned between the sprocket 6 and the driven sprocket 7, and the total weight of the weights 9 and residual weights 10 acts on the chain 8 as a vertical load in the rotational direction of the chain 8 indicated by arrow C in the figure.

[0030] The vertical load acting on the chain 8 acts as a vertically upward biasing force, indicated by arrow A in the diagram, which raises the door panel 2 via the sprocket 6, winding shaft 5, wire winding drum 4, and wire 3. Therefore, when raising the door panel 2 to transition from the closed state to the open state (during the opening operation of the door panel 2), the door panel 2 can be raised with minimal force. In this way, when the door panel 2 is closed, the weight 9 and the residual weight 10 apply a biasing force to the winding shaft 5 in the direction of winding up the wire 3.

[0031] Next, when the door panel 2 is raised, as shown in Figure 3(a), the roller 23 at the upper end of the door panel 2 reaches the starting point of the second guide rail 112 (the midpoint of the R section 113). At this time, as shown in Figure 3(b), the lower end of the weight 9 (the tip in the rotational direction of the chain 8) that moves in the rotational direction of the chain 8, indicated by arrow C in the figure, is positioned at the bottom of the driven sprocket 7. Therefore, until the roller 23 at the upper end of the door panel 2 reaches the starting point of the second guide rail 112 (the midpoint of the R section 113), the entire weight of the weight 9 and the remaining weight 10 acts as a biasing force in the vertical upward direction, indicated by arrow A in the figure, which lifts the door panel 2.

[0032] As the door panel 2 is raised further, the roller 23 at the upper end of the door panel 2 passes the starting point of the second guide rail 112 (the midpoint of the R section 113), and the tip (lower end) of the weight 9 in the rotational direction of the chain 8 passes the bottom of the driven sprocket 7, changing from descending to ascending. In the rotational direction of the chain 8 indicated by arrow C in the figure, a portion of the weight 9 rises and is positioned between the bottom of the driven sprocket 7 and the sprocket 6. At this time, in the direction of rotation of chain 8 indicated by arrow C in the figure, the weights of weight 9 and residual weight 10, which are positioned between sprocket 6 and the bottom of driven sprocket 7, act on chain 8 as a vertical load in the direction of rotation of chain 8 indicated by arrow C in the figure. On the other hand, in the direction of rotation of chain 8 indicated by arrow C in the figure, the weight of weight 9, which is positioned between the bottom of driven sprocket 7 and sprocket 6, acts on chain 8 as a vertical load in the opposite direction to the direction of rotation of chain 8 indicated by arrow C in the figure.

[0033] Therefore, after the roller 23 at the upper end of the door panel 2 reaches the starting point of the second guide rail 112 (the midpoint of the R section 113), not the entire weight of the weight 9 and the remaining weight 10, but rather a portion of the weight of the weight 9 and the remaining weight 10 will act as a vertically upward biasing force, indicated by arrow A in the figure, that lifts the door panel 2. Furthermore, as the door panel 2 rises, the weight 9 positioned between the bottom of the driven sprocket 7 and the sprocket 6 increases in the rotational direction of the chain 8 indicated by arrow C in the figure, and the upward biasing force in the vertical direction indicated by arrow A in the figure that raises the door panel 2 decreases. In this way, when the door panel 2 transitions from a closed state to an open state, the weight 9 passes the lowest part of the driven sprocket 7 and changes from downward to upward, reducing the biasing force on the winding shaft 5 in the direction of winding up the wire 3.

[0034] Next, when the door panel 2 is raised and opened, the lower end of the door panel 2 is positioned approximately at the same location as the lower end of the wall P, as shown in Figure 4(a). At this time, as shown in Figure 4(b), in the rotation direction of the chain 8 indicated by arrow C in the figure, the entire weight 9 passes through the driven sprocket 7, changing from downward to upward and being positioned between the lowest part of the driven sprocket 7 and the sprocket 6. The remaining weight 10 does not pass through the driven sprocket 7 but is positioned between the sprocket 6 and the lowest part of the driven sprocket 7. Therefore, the difference in weight between the weight MW of weight 9 and the weight SW of the remaining weight 10 becomes the force acting on chain 8. In this way, when the door panel 2 is open, the weight 9 that has passed the bottom of the driven sprocket 7 and the remaining weight 10 that has not passed the bottom of the driven sprocket 7 apply a biasing force to the winding shaft 5 in the direction of winding up the wire 3.

[0035] In this embodiment, as described above, the weight MW of weight 9 is (W1-W2) / 2 and the weight SW of residual weight 10 is (W1+W2) / 2. Therefore, a biasing force corresponding to the weight W2 can be applied to the door panel 2 in the vertically upward direction, and the door panel 2 is maintained in the open state. In this embodiment, as the door panel 2 rises, the weight 9 passes through the driven sprocket 7 and changes from descending to rising, thereby gradually decreasing the upward biasing force in the vertical direction indicated by arrow A in the figure that causes the door panel 2 to rise.

[0036] Furthermore, when lowering the door panel 2 from the open state shown in Figure 4 to the closed state shown in Figure 2 (when closing the door panel 2), the action is the opposite of when raising the door panel 2. As the door panel 2 descends, the weight 9 passes through the driven sprocket 7 and changes from descending to ascending, so that the upward biasing force indicated by arrow A in the figure, which raises the door panel 2, gradually increases. Note that the rotation direction of the chain 8 is the opposite direction when the door panel 2 is raised.

[0037] A modified example of this embodiment will be described. Figure 5 is an explanatory diagram of the weight position in the modified example. As shown in Figure 5, when the door panel 2 is closed, an auxiliary weight 9a may be positioned near the top of the sprocket 6, between the bottom of the driven sprocket 7 and the sprocket 6 in the direction of rotation of the chain 8 indicated by arrow C in the figure. This auxiliary weight 9a constitutes part of the weight of the weight 9 shown in Figure 2. This reduces the upward biasing force, indicated by arrow A in the diagram, that causes the door panel 2 to rise when it is closed, thereby enabling the door panel 2 to maintain its closed position.

[0038] Furthermore, when the door panel 2 is moved to the open position, the auxiliary weight 9a, which is part of the weight 9 (counterweight), passes over the top of the sprocket 6 and changes from rising to falling, and is positioned between the sprocket 6 and the driven sprocket 7 in the rotational direction of the chain 8. Therefore, the entire weight of weight 9, including the auxiliary weight 9a, and the remaining weight 10 act as a vertically upward biasing force, indicated by arrow A in the figure, which lifts the door panel 2.

[0039] Next, an example in which the shape of the guide rail 11 is deformed will be described. Figure 6 is an explanatory diagram illustrating the position of the door panel and weight in the embodiment. As shown in Figure 6, in the case of a guide rail 11 where the distance between the roller 23 at the upper end of the door panel 2 and the starting point of the second guide rail 112 (midpoint of the R section 113) is small, the distance between the lower end of the weight 9 and the lowest part of the driven sprocket 7 may be reduced. As a result, the roller 23 at the upper end of the door panel 2 passes the starting point of the second guide rail 112 (the midpoint of the R section 113), and the tip (lower end) of the weight 9 in the rotational direction of the chain 8 passes the bottom of the driven sprocket 7, changing from downward to upward, so that in the rotational direction of the chain 8 indicated by arrow C in the figure, a portion of the weight 9 rises and is positioned between the bottom of the driven sprocket 7 and the sprocket 6.

[0040] Figure 7 is an explanatory diagram for when the overhead door moves up and down in a nearly vertical direction, and is an explanatory diagram when the angle between the extension of the first guide rail 111 and the second guide rail 112 is approximately 0 degrees. Figure 7(a) shows the closed state of the door panel 2 and the positional relationship of the weight and residual weight in that state, and Figure 7(b) shows the open state of the door panel 2 and the positional relationship of the weight and residual weight in that state.

[0041] When the overhead door moves up and down in a nearly vertical direction, as shown in Figure 7(a), when the door panel 2 is closed, the residual weight 10 is positioned between the sprocket 6 and the driven sprocket 7 in the direction of rotation of the chain 8 indicated by arrow C in the figure, weight 9a is positioned at the top of the sprocket 6, and weight 9b is positioned between the driven sprocket 7 and the sprocket 6 in the direction of rotation of the chain 8 indicated by arrow C in the figure. Furthermore, if we let W1 be the vertical weight of door panel 2 when it is closed and when it is open, WS be the weight of residual weight 10, Wa be the weight of weight 9a, and Wb be the weight of weight 9b, then W1 = WS + Wa - Wb.

[0042] When the door panel 2 is raised, as shown in Figure 7(a), the weight 9a, which moves in the rotational direction of the chain 8 indicated by arrow C in the figure, passes over the top of the sprocket 6 and is positioned below the top. Therefore, the weight of "residual weight 10 (WS) + weight of weight 9a (Wa) - weight of weight 9b (Wb)" acts as a biasing force in the vertical upward direction, indicated by arrow A in the diagram, which causes door panel 2 to rise.

[0043] Furthermore, when the door panel 2 is raised to open, as shown in Figure 7(b), the residual weight 10 and weight 9a are positioned between the sprocket 6 and the driven sprocket 7 in the direction of rotation of the chain 8 indicated by arrow C in the figure, and weight 9b, as part of the counterweight, passes over the top of the sprocket 6, changes from rising to descending, and is positioned between the sprocket 6 and the driven sprocket 7 in the direction of rotation of the chain 8. At this time, the weight of "residual weight 10 (WS) + weight of weight 9a (Wa) + weight of weight 9b (Wb)" acts as a vertically upward biasing force, indicated by arrow A in the diagram, which lifts the door panel 2. Therefore, the door panel 2 can be kept open.

[0044] Thus, in this embodiment, as the door panel 2 moves up and down, the weight 9b passes through the sprocket 6, thereby changing the biasing force in the vertical upward direction indicated by arrow A in the figure.

[0045] Here, if the balance between the weight of the door panel 2 and the weight of the weight providing the vertical upward biasing force can be any position, the operating force required to raise the door panel 2 can be reduced. However, this also means that the door panel 2 can stop at any position between the closed and open states, which can be inconvenient. For example, if the door panel 2 is stopped before opening and a tall vehicle passes over it, it could lead to damage to the door panel 2. Therefore, it is desirable to increase the vertical upward biasing force when opening the door panel 2 to maintain a fully open state.

[0046] Therefore, as described above, when the door panel 2 is moved to the open position, the weight 9b passes over the top of the sprocket 6 and changes from rising to falling, so that it is positioned between the sprocket 6 and the driven sprocket 7 in the rotational direction of the chain 8. This increases the biasing force in the vertical upward direction when the door panel 2 is opened, and it is possible to maintain a fully open state. Note that while Figure 7 shows an example where the door panel 2 is composed of multiple bendable panels, in this rail shape the door panel 2 does not bend, so it may be composed of a single panel.

[0047] Figure 8 is an explanatory diagram of the shape of the guide rail. As shown in Figure 8, the guide rail 11 can be made into various shapes depending on the space (location of ceiling T) in which the overhead door is installed.

[0048] Figure 8(a) shows the case where the guide rail 11 has a small gap between the roller 23 at the upper end of the door panel 2 and the starting point of the second guide rail 112 (midpoint of the R section 113), as shown in Figure 6. In this case, the shape of the guide rail 11 can be easily adapted by arranging the weight 9 so that the gap between the lower end of the weight 9 and the lowest part of the driven sprocket 7 is small.

[0049] Figure 8(b) shows the case where the guide rail 11 has a large gap between the roller 23 at the upper end of the door panel 2 and the starting point of the second guide rail 112 (midpoint of the R section 113), as shown in Figures 2 to 4. In this case, the shape of the guide rail 11 can be easily accommodated by arranging the weight 9 so that the gap between the roller 23 at the upper end of the door panel 2 and the starting point of the second guide rail 112 (midpoint of the R section 113) is equal to the gap between the lower end of the weight 9 and the lowest part of the driven sprocket 7.

[0050] Furthermore, as shown in Figure 8(a), if the travel distance of the door panel 2 on the second guide rail 112 is longer and the vertical travel distance is shorter compared to Figure 8(b), the stroke, which is the range of movement of the weight 9, may become insufficient. In this case, the stroke of the weight 9 can be reduced by making the diameter of the sprocket 6 smaller than the diameter of the winding drum 4 shown in Figure 1.

[0051] Furthermore, Figure 8(c) shows the case where the door panel 2 moves up and down in a substantially vertical direction, as shown in Figure 7, and the angle between the extension of the first guide rail 111 and the second guide rail 112 is approximately 0 degrees. In this case, as described above, the shape of the guide rail 11 can be easily accommodated by arranging the weights 9a, 9b, and residual weight 10. The weights of weight 9, weight 9a, weight 9b, and residual weight 10 in the cases shown in Figures 8(a) to 8(c) are as described above.

[0052] Figure 8(d) shows the case where the angle between the extension of the first guide rail 111 and the second guide rail 112 is approximately 30 degrees. In this case as well, as described above, if W1 is the weight of the door panel 2 in the vertical direction (along the first guide rail 111) when it is closed, and W2 is the weight of the door panel 2 in the vertical direction (along the first guide rail 111) when it is open, then the total weight MW of weight 9 is (W1-W2) / 2. Also, the weight SW of the remaining weight 10 is the total weight of weight 9 plus W2, so it is (W1+W2) / 2. Furthermore, as explained in Figure 8(a), by placing the weight 9 on the chain 8, it is possible to easily accommodate the shape of the guide rail 11.

[0053] As shown in Figure 1, some door panels 2 have special functions such as windows, and their weight may vary. In this embodiment, since a weight 9 with multiple bendable weights is attached to the chain 8, it is possible to easily accommodate various door panels 2 by increasing or decreasing the weight of the weight 9 at the corresponding position to match the weight of each individual door panel 2. For example, a door panel 2 with a window tends to be heavier than a door panel 2 without a window. By increasing the weight 9 at the position corresponding to a door panel 2 with a window to match the weight of the door panel 2 with a window, a well-balanced overhead door 1 can be created.

[0054] As described above, in this embodiment, a plurality of flexible weights 9 are attached to the chain 8, which apply a biasing force to the winding shaft 5 in the direction of winding up the wire 3. As the door panel 2 moves up and down, the weights 9 pass through the sprocket 6 or the driven sprocket 7, changing their biasing force. This provides the advantage of being able to easily accommodate various shapes of the guide rail 11 of the door panel 2. Furthermore, when the door panel 2 rises vertically upward along the first guide rail 111, there is no change in the biasing force on the door panel 2, and when it moves along the second guide rail 112, the biasing force on the door panel 2 can be reduced. Thus, the door panel 2 can easily accommodate various shapes of the guide rail 11.

[0055] Furthermore, by connecting chain 8 in a ring shape and wrapping it around the two sprockets, it is possible to suppress tooth misalignment and detachment of chain 8 even without tension weights or other means to apply tension to chain 8. In addition, the weight 9 can be folded back with a simple structure, resulting in space savings. Furthermore, because the weight 9, which weighs approximately half the weight of the door panel 2, is moved from downward to upward by the driven sprocket 7, the force acting due to the inertia of the weight 9 is reduced, eliminating the need to increase the structural strength and resulting in a simpler structure. This also reduces noise and improves operability.

[0056] In this embodiment, the overhead door 1 is described as one in which the door panel 2 is raised and lowered by manual operation. However, the overhead door 1 may also be one in which the door panel 2 is raised and lowered by the power of an electric motor. In this case, low power consumption and high durability can be achieved. Furthermore, although this embodiment describes the arrangement of the sprocket 6, driven sprocket 7, chain 8, and weight 9 on one side, when using a wide door panel 2 or a heavy door panel 2, the sprocket 6, driven sprocket 7, chain 8, and weight 9 may be arranged on both the left and right sides of the door panel 2. [Explanation of symbols]

[0057] 1 Overhead Door 2 Door Panels 3 wires 4 (4a, 4b) Wire winding drum 5. Winding shaft 6 sprocket 7 Driven sprocket 8 chains 9 weights 10 Remaining weight 11 (11a, 11b) Guide rail 111 (111a, 111b) First guide rail 112 (112a, 112b) Second guide rail

Claims

1. In an overhead door that uses a door panel made of multiple panels connected in a flexible manner to move between an open and closed state by raising and lowering, A rotating shaft to which a drum for winding a wire connected to the door panel is fixed, A first sprocket fixed to the aforementioned rotating shaft, A second sprocket, positioned below the first sprocket and rotatable, A rotatable chain stretched between the first sprocket and the second sprocket, Equipped with, The chain is fitted with a plurality of flexible weights that apply a biasing force to the rotating shaft in the direction of winding up the wire. An overhead door characterized in that, as the door panel moves up and down, the weight passes the lowest part of the second sprocket, thereby changing the biasing force.

2. In the overhead door according to claim 1, A first guide rail that guides the door panel in the vertical direction, A second guide rail is continuous with the first guide rail and formed to form a predetermined angle with the first guide rail, and guides the door panel. Equipped with, An overhead door characterized in that, when the door panel is opened, the tip of the weight passes the lowest part of the second sprocket and changes from downward to upward when the tip of the door panel reaches the starting point of the second guide rail.

3. In the overhead door according to claim 2, The chain has a first weight consisting of a series of bendable weights and a second weight that does not bend attached to it. The entirety of the first weight is capable of passing through the lowest part of the second sprocket. An overhead door characterized in that the second weight moves up and down between the first sprocket and the second sprocket without passing through the lowest part of the second sprocket.

4. In the overhead door according to claim 3, When the door panel is closed, the first weight and the second weight apply a biasing force to the rotation axis in the direction of winding up the wire. When the door panel transitions from a closed state to an open state, the first weight passes the lowest part of the second sprocket and changes from downward to upward, reducing the biasing force in the direction of winding the wire with respect to the rotating shaft. An overhead door characterized in that, when the door panel is in the open position, the first weight that has passed the lowest part of the second sprocket and the second weight that has not passed the lowest part of the second sprocket apply a biasing force to the rotating shaft in the direction of winding up the wire.

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