Device to prevent excessive flap opening with a backflow prevention damper structure with a balance weight

Abstract

We provide a flap excessive opening prevention device with a backflow prevention damper structure with a balance weight. [Solution] The backflow damper structure with balance weight includes a backflow damper housing 1, a rotating shaft 2 attached inside the backflow damper housing, and a first loose-leaf flap 3 and a second loose-leaf flap 4, the first loose-leaf flap and the second loose-leaf flap are rotatably fixed to both sides of the rotating shaft, respectively. The flap excessive opening prevention device includes a position limiting device 5 attached inside the backflow damper housing, which is located above the rotating shaft and limits the maximum opening angle of the first loose-leaf flap and the second loose-leaf flap to 90 degrees or less at the same time.

Description

[Technical field]

[0001] The present invention relates to the field of fan system structures, and more particularly to a flap excessive opening prevention device for a backflow prevention damper structure with a balance weight. [Background technology]

[0002] Generally, there are two fans used in wind power systems, one is used and the other is a reserve, arranged in parallel. Usually, a backflow prevention damper is separately installed at the fan outlet. One type of backflow prevention damper is a backflow prevention damper with a balance weight, which uses a double loose-leaf flap consisting of two semicircular loose-leaf flaps, mounted on an axis to form a flap door, one of which is freely reversible and the other is fixedly connected to the balance weight handle, thereby achieving the effect of backflow prevention.

[0003] This type of backflow damper with counterweight has a simple structure and a large flow area, but if the shaft of the loose-leaf flap gets slightly stuck during operation, or if one of the loose-leaf flaps reverses excessively when the fan is switched on, the two loose-leaf flaps will be folded together by the wind pressure and cannot be returned to their original position without dismantling the damper, leading to the failure of the backflow damper, keeping half of the air duct's flow area normally open, causing the backup fan to reverse, and generating a large current in the other started fan. Summary of the Invention [Means for solving the problem]

[0004] The purpose of this invention is to provide a flap excessive opening prevention device for a backflow damper structure with a balance weight in order to overcome the drawbacks of the conventional technology in that when one of the flaps of a conventional backflow damper with a balance weight is excessively reversed, the two flaps are folded over due to wind pressure, and cannot be returned to their original position without disassembling the damper, resulting in the backflow damper breaking down.

[0005] The objective of the present invention may be achieved by the following technical solutions:

[0006] A flap excessive opening prevention device for a backflow damper structure with a balance weight, the backflow damper structure with a balance weight including a backflow damper housing, a rotating shaft attached inside the backflow damper housing, and a first loose-leaf type flap and a second loose-leaf type flap, the first loose-leaf type flap and the second loose-leaf type flap are rotatably fixed to both sides of the rotating shaft, respectively, and the flap excessive opening prevention device includes a position limiting device attached inside the backflow damper housing, the position limiting device being located above the rotating shaft and being used to simultaneously limit the maximum opening degrees of the first loose-leaf type flap and the second loose-leaf type flap to 90 degrees or less.

[0007] Furthermore, the position limiting device is a fixed post that is fixed to the inner wall of the housing of the backflow prevention damper and is parallel to the rotation axis.

[0008] Furthermore, the fixed post is made of metal.

[0009] Furthermore, the fixing pole is fixed to the inner wall of the housing of the backflow prevention damper by welding.

[0010] Furthermore, the length of the overlapping area between the fixing post and the reversible range of the first loose-leaf type flap is equal to or greater than one-fourth of the length of the cross section of the first loose-leaf type flap where the overlapping area is located; The length of the overlapping area between the fixing post and the reversible range of the second loose-leaf flap is equal to or greater than one-fourth the length of the cross section of the second loose-leaf flap where the overlapping area is located.

[0011] Furthermore, the cross section of the fixing post is circular or polygonal.

[0012] Furthermore, the horizontal width of the fixed post is equal to or greater than the horizontal width of the rotating shaft.

[0013] Furthermore, the distance between the fixed post and the rotation shaft is within a range of 0.3 to 0.7 times the height of the reversible range of the first loose-leaf type flap and the second loose-leaf type flap.

[0014] Furthermore, the inside of the housing of the backflow prevention damper is a cylindrical hollow area, and both the first loose-leaf type flap and the second loose-leaf type flap have a semicircular structure.

[0015] Furthermore, the number of the position limiting devices may be one or more.

[0016] Compared with the prior art, the present invention has the following advantages: (1) The invention provides a position limiting device directly above the rotation axis in the housing of the backflow damper, so that when the air duct fan in which the backflow damper is installed is working normally, both loose-leaf flaps can open normally, and during opening, they are blocked by the position limiting device so that the maximum opening angle is 90°, thereby ensuring that the two loose-leaf flaps are not over-opened, and after the air duct fan is stopped, the loose-leaf flaps will automatically return to their original position without affecting their normal operation, thus overcoming the problem that the traditional loose-leaf flaps are over-opened and cause the backflow damper to fail. (2) The structure is simple and low cost. All that is required is to install a fixed column directly above the rotating shaft. (3) Safe and reliable: No additional equipment is required, and the fixed column can be connected only by electric welding, so that the normal operation of the loose-leaf flap is not affected. (4) Wide applicability. This device is not limited to a specific fixed shape and can be applied to backflow prevention dampers with balance weights of various sizes. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a three-dimensional structural diagram of a flap excessive opening prevention device of a backflow prevention damper with a counterweight provided in an embodiment of the present invention. [Diagram 2] FIG. 2 is a top view showing the structure of a flap excessive opening prevention device of a backflow prevention damper with a counterweight provided in an embodiment of the present invention. [Diagram 3] FIG. 3 is a schematic diagram illustrating a usage state of a flap excessive opening prevention device of a backflow prevention damper with a counterweight provided in an embodiment of the present invention. [Figure 4] FIG. 4 is a schematic diagram of a flap excessive opening prevention device of a backflow prevention damper with a counterweight provided in accordance with an embodiment of the present invention, in which the second loose-leaf flap is restricted. [Explanation of symbols]

[0018] 1, backflow prevention damper housing; 2, rotating shaft; 3, first loose-leaf type flap; 4, second loose-leaf type flap; 5, position limiting device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] In order to make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. The components of the embodiments of the present invention, as generally described and illustrated in the accompanying drawings, may be arranged and designed in a variety of different configurations.

[0020] Therefore, the following detailed description of the embodiments of the present invention, provided in the accompanying drawings, is not intended to limit the scope of the claimed invention, but rather to represent selected embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are included in the scope of protection of the present invention.

[0021] It should be noted that in the following figures, like reference numbers and letters represent like items, so that once an item is defined in one figure, further definition and explanation is not required in subsequent figures.

[0022] In the description of the present invention, the orientations and positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner" and "outer" are based on the orientations and positional relationships shown in the drawings or the orientations and positional relationships in which the product of the present invention is usually placed when used. This is only for the purpose of explaining and simplifying the description of the present invention, and does not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0023] It should be noted that the terms "first" and "second" are used for convenience of description only and cannot be understood as indicating or implying relative importance or quantity of technical features. Thus, features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, "plurality" means two or more than two, unless expressly limited otherwise.

[0024] Additionally, terms such as "horizontal" and "vertical" do not mean that a member needs to be perfectly horizontal or suspended, but may tilt slightly. For example, "horizontal" only means that the direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may tilt slightly. EXAMPLES

[0025] As shown in Figures 1 and 2, this embodiment provides a flap excessive opening prevention device for a backflow damper structure with a balance weight, the backflow damper structure with a balance weight includes a backflow damper housing 1, a rotating shaft 2 mounted inside the backflow damper housing 1, a first loose-leaf type flap 3 and a second loose-leaf type flap 4, the first loose-leaf type flap 3 and the second loose-leaf type flap 4 are rotatably fixed on both sides of the rotating shaft 2, respectively, and the flap excessive opening prevention device includes a position limiting device 5 mounted inside the backflow damper housing 1, the position limiting device 5 is located above the rotating shaft 2 and is used to simultaneously limit the maximum opening degrees of the first loose-leaf type flap 3 and the second loose-leaf type flap 4 to less than 90 degrees.

[0026] Specifically, the position limiting device 5 is a fixed column that is fixed to the inner wall of the housing 1 of the backflow prevention damper and is parallel to the rotation axis 2 .

[0027] Optionally, the fixed post is made of metal, which is more stable and reliable.

[0028] The metal fixing pole may be fixed to the inner wall of the housing 1 of the backflow damper by welding.

[0029] Preferably, the length of the overlapping area between the fixing post and the reversible range of the first loose-leaf type flap 3 is equal to or greater than a quarter of the length of the cross section of the first loose-leaf type flap 3 where the overlapping area is located; The length of the overlapping area between the fixed post and the reversible range of the second loose-leaf flap 4 is equal to or greater than one-fourth the length of the cross section of the second loose-leaf flap 4 where the overlapping area is located.

[0030] By limiting the length of the fixed pillar as described above, the fixed pillar can reliably and effectively limit the rotation of the first loose-leaf flap 3 and the second loose-leaf flap 4, thereby avoiding the problem that the rotation speed or force of the loose-leaf flaps is too strong and the fixed pillar cannot stop their rotation.

[0031] The horizontal width of the fixed pillar is equal to or greater than the horizontal width of the rotating shaft 2.

[0032] By limiting the horizontal width of the fixed column, the inversion of the first loose-leaf type flap 3 and the second loose-leaf type flap 4 can be limited to a maximum of 90°, thereby preventing the problem of being unable to return to the original position if they are inverted beyond 90°.

[0033] The distance between the fixed post and the rotating shaft 2 is within a range of 0.3 to 0.7 times the height of the reversible range of the first loose-leaf type flap 3 and the second loose-leaf type flap 4 .

[0034] By limiting the distance between the fixed post and the rotating shaft 2, the fixed post can effectively block the rotating shaft 2 and reduce the impact force on the fixed post, preventing the fixed post from being too close to the rotating shaft 2 to effectively block the loose-leaf flap, or the fixed post from being too far from the rotating shaft 2 to cause the loose-leaf flap to apply excessive impact force to the fixed post and damage the equipment.

[0035] The cross section of the fixing post may be circular or polygonal, such as triangular, rectangular or square.

[0036] The number of position limiting devices 5 may be one or more, and is not limited to this, and multiple position limiting devices 5 may be provided on opposite sides of the housing 1 of the backflow prevention damper, or may be provided side by side in the vertical direction.

[0037] In this embodiment, the inside of the housing of the backflow prevention damper is a cylindrical hollow area, and both the first loose-leaf type flap 3 and the second loose-leaf type flap 4 have a semicircular structure.

[0038] The position limiting device 5 is a fixed column having a cylindrical structure that is disposed directly above the rotation shaft 2 .

[0039] Its working principle is as follows: when the fan in the air duct where the backflow prevention damper is located is working normally, both loose-leaf type flaps can open normally, and during opening, they are blocked by the position limiting device 5, so that the maximum opening angle is 90°. As shown in Figure 3, it is in the inverted state where the two loose-leaf type flaps are working normally, and as shown in Figure 4, it is in the state where the second loose-leaf type flap 4 is inverted to the maximum, and its maximum inversion angle is limited by the position limiting device 5.

[0040] This device does not affect the flow area of ​​the air duct. When the fan in the air duct where the backflow prevention damper is located is switched to standby mode and stopped, even if the loose-leaf shaft is slightly stuck, the loose-leaf type flap cannot be over-reversed because of the short rod, and the wind pressure can overcome the stuckness and push the two loose-leaf type flaps to the closed state.

[0041] The above is a detailed description of the preferred specific embodiments of the present invention. It should be understood that those skilled in the art can make many modifications and changes based on the concept of the present invention without creative efforts. Therefore, any technical solution that those skilled in the art can obtain based on the concept of the present invention and on the prior art through logical analysis, reasoning, or limited experimentation should be within the scope of protection determined by the claims.

Claims

1. A flap excessive opening prevention device for a backflow prevention damper structure with a balance weight, the backflow prevention damper structure with a balance weight includes a backflow prevention damper housing (1), a rotating shaft (2) attached inside the backflow prevention damper housing (1), a first loose-leaf type flap (3) and a second loose-leaf type flap (4), the first loose-leaf type flap (3) and the second loose-leaf type flap (4) being rotatably fixed to both sides of the rotating shaft (2), respectively. A flap excessive opening prevention device for a backflow damper structure with a balance weight, the flap excessive opening prevention device including a position limiting device (5) attached inside the housing (1) of the backflow damper, the position limiting device (5) being located above the rotation shaft (2) and used to simultaneously limit the maximum opening degree of a first loose-leaf type flap (3) and a second loose-leaf type flap (4) to 90 degrees or less.

2. The flap excessive opening prevention device of the backflow damper structure with balance weight as described in claim 1, characterized in that the position limiting device (5) is a fixed column fixed to the inner wall of the housing (1) of the backflow damper and parallel to the rotation axis (2).

3. The device for preventing excessive opening of a flap in a backflow prevention damper structure with a balance weight according to claim 2, characterized in that the fixed column is made of metal.

4. The device for preventing excessive flap opening in a backflow damper structure with a balance weight according to claim 3, characterized in that the fixed column is fixed to the inner wall of the housing (1) of the backflow damper by welding.

5. the length of the overlapping area between the fixing post and the reversible range of the first loose-leaf type flap (3) is equal to or greater than one-fourth of the length of the cross section of the first loose-leaf type flap (3) where the overlapping area is located; The flap excessive opening prevention device of the backflow prevention damper structure with balance weight described in claim 2, characterized in that the length of the overlapping area between the fixed post and the invertible range of the second loose-leaf type flap (4) is at least one-fourth of the length of the cross section of the second loose-leaf type flap (4) in which the overlapping area is located.

6. The device for preventing excessive opening of a flap in a backflow prevention damper structure with a balance weight according to claim 2, characterized in that the cross section of the fixed post is circular or polygonal.

7. The device for preventing excessive flap opening in a backflow prevention damper structure with a balance weight as described in claim 2, characterized in that the horizontal width of the fixed column is equal to or greater than the horizontal width of the rotating shaft (2).

8. The flap excessive opening prevention device of the backflow prevention damper structure with balance weight described in claim 2, characterized in that the distance between the fixed column and the rotating shaft (2) is within the range of 0.3 to 0.7 times the height of the invertible range of the first loose-leaf type flap (3) and the second loose-leaf type flap (4).

9. The flap excessive opening prevention device for the backflow prevention damper structure with balance weight described in claim 1, characterized in that the inside of the housing (1) of the backflow prevention damper is a cylindrical hollow area, and the first loose-leaf type flap (3) and the second loose-leaf type flap (4) both have a semicircular structure.

10. The device for preventing excessive flap opening in a backflow prevention damper structure with a balance weight as described in claim 1, characterized in that the number of the position limiting devices (5) is one or more.

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