Industrial ceiling fan blade assembly

Abstract

This invention relates to ceiling fans, and more particularly to an industrial ceiling fan. The industrial ceiling fan blade assembly has a tail fin at its tail end, and one side of the blade body has a streamlined cavity with reinforcing ribs. The blade head is held by upper and lower stress plates, and a blade safety component is located within the cavity. The upper and lower stress plates and the blade safety component are fixed together by a set of through bolts. A spacer is also provided between the upper and lower stress plates, and this spacer is fixed by countersunk screws inserted through the upper stress plate. This invention is an externally clamped insert type, resulting in low equivalent stress levels at various points on the blade; the blade is thin and lightweight, with a small load; the insert structure is composed of sheet metal parts, resulting in lower cost.

Description

Technical Field

[0001] This invention relates to ceiling fans, and more particularly to an industrial ceiling fan. Background Technology

[0002] Currently in the industrial fan market, the blade assemblies for fans with a diameter of 6.1 meters or more still largely use sheet metal inserts. Due to the long blade length, a single sheet metal piece is insufficient to guarantee the blade's drooping and floating height. In addition, the cross-sectional area of ​​the insert sheet metal is small, resulting in greater pressure under stress. Insufficient sheet metal rigidity leads to stress concentration at the connection point with the blade, resulting in a larger equivalent stress.

[0003] Some fan blade assemblies using external clamp inserts have only through ribs inside, and the spacing of these through ribs is unreasonable. After the bolts are tightened, the fan blades deform, causing the roots of the through ribs to be stressed simultaneously. During fan operation, the fan blades move up and down, and the through ribs also move up and down repeatedly, subjecting the roots to alternating stress. The most severe stress occurs at the junction of the insert and the fan blade, leading to fatigue fracture after prolonged operation. Summary of the Invention

[0004] The purpose of this invention is to overcome the above-mentioned shortcomings and provide an industrial ceiling fan blade assembly. The fan blades of this invention are thin and light, reducing stress and reducing cost.

[0005] The present invention is implemented as follows: an industrial ceiling fan blade assembly, which has a tail fin at the tail end, and a streamlined cavity on one side of the cross-section of the blade body, with reinforcing ribs inside the cavity. The blade head is held by upper and lower stress plates, and a blade safety component is provided inside the cavity. The upper and lower stress plates and the blade safety component are fixed together by a set of through bolts. A pad is also provided between the upper and lower stress plates, and the pad is fixed by a countersunk screw that passes through the lower stress plate.

[0006] The industrial ceiling fan blade assembly has a blade pad between the lower surface of the blade and the lower stress plate. The curvature of the upper surface of the blade pad is the same as that of the lower surface of the blade. The pad fits snugly and the contact surface is an arc surface. It is fixed by two of the through bolts in the set.

[0007] The industrial ceiling fan blade assembly has a blade pad with a certain length, and the blade facing the tail end of the blade is provided with a through bolt passing through the blade cavity.

[0008] The industrial ceiling fan blade assembly includes two through ribs and two pairs of half ribs in the upper cavity. The through ribs are located on both sides of the blade cavity, and the two pairs of half ribs are located in the middle. The blade pad is inserted between the two pairs of half ribs.

[0009] The aforementioned industrial ceiling fan blade assembly includes a blade pad made of a profile with two through holes.

[0010] The fan blades of this invention are thin and lightweight, resulting in low cost. Under the same operating conditions of the motor, the airflow coverage area is larger. Therefore, without reducing the airflow, the fan speed can be appropriately reduced, thus improving the fan life. The fan blade safety component installed inside the fan blade cavity reduces the deformation of the fan blade caused by the compression of the fan blade after the bolts are tightened. At the same time, it can reduce the equivalent stress around the bolts and at the junction of the stress plate and the fan blade, avoiding the risk of fan blade fracture due to fatigue. The two components are fitted with an interference fit (tight fit), which is more effective in preventing fan blade deformation and reducing equivalent stress. The external stress plate component has a simple structure, simple processing technology, low cost, and high rigidity. For industrial fans with large diameters and single fan blades up to 3.3M long, it can reduce the difference between fan blade sag and buoyancy. The fan blade pad contacts the arc surface of the fan blade, reducing stress concentration and improving the fan blade life. Attached Figure Description

[0011] The invention will now be further described with reference to the accompanying drawings:

[0012] Figure 1 This is a schematic diagram of the present invention;

[0013] Figure 2 This is a schematic diagram of the fan blade shape;

[0014] Figure 3 This is a cross-sectional view of the fan blade. Detailed Implementation

[0015] like Figures 1-3 As shown, the overall structure of the fan blade assembly is a fan blade assembly with stress plates clamped externally and safety components inserted internally.

[0016] The main body is the fan blade 9, whose outer contour design conforms to aerodynamic principles. The fan blade contains two through ribs 11 and four semi-ribs 12. The through ribs 11 are designed to improve the fan blade's rigidity and reduce the sag difference at the fan blade's tail end in a stationary state and the upward difference at the fan blade's tail end in an operating state. The semi-ribs are designed to limit the installation of the fan blade's safety components.

[0017] The fan blade safety component 6 is installed inside the fan blade cavity, at the location of the four and a half ribs. The fan blade safety component 6 and the four and a half rib cavities are in an interference fit, that is, face to face tight fit. When the final bolts are tightened, it serves to support the entire inner cavity.

[0018] A tail fin 10 is installed at the end of the fan blade. The tail fin and the fan blade are in an embedded and wrapped form. They are fastened by an M5 screw and an M5 anti-loosening nut 3, providing multiple protections to avoid the risk of falling.

[0019] The stress plate 5 and the fan blade pad 7 are placed on the limiting fixture table and assembled and fixed by M6-16 internal hex countersunk screws.

[0020] The upper stress plate 1, lower stress plate 5, and stress plate pad 4 are placed on the limiting fixture and assembled and fixed using M6-16 socket head cap screws 2. At this point, the stress plate outer clamp assembly is complete.

[0021] Insert the stress plate outer clamp assembly into the fan blade, with the lower surface of the upper stress plate fitting against the upper surface of the fan blade, and the upper surface of the fan blade pad fitting against the lower surface of the fan blade.

[0022] The fan blade assembly is secured by M10-50 external hex bolt assembly and M10-70 external hex bolt assembly 8.

Claims

1. An industrial ceiling fan blade assembly, characterized in that it has a tail fin at the rear end, and one side of the cross-section of the blade body is a streamlined cavity with reinforcing ribs inside the cavity. The fan blade head is held by upper and lower stress plates, and a fan blade safety component is installed in the cavity. The upper and lower stress plates and the fan blade safety component are fixed together by a set of through bolts. A pad is also provided between the upper and lower stress plates, and the pad is fixed by a countersunk screw that passes through the lower stress plate. A fan blade pad is provided between the lower surface of the fan blade and the lower stress plate. The curvature of the upper surface of the fan blade pad is the same as that of the lower surface of the fan blade, and they are fitted together to form an arc-shaped contact surface. It is fixed by two of the through bolts. The fan blade pad has a certain length, and a through bolt is also provided on the fan blade facing the tail end of the fan blade, passing through the fan blade cavity. The reinforcing ribs include two through ribs and two pairs of half ribs. The through ribs are located on both sides of the fan blade cavity, and the two pairs of half ribs are located in the middle. The fan blade safety component is inserted between the two pairs of half ribs. The fan blade safety component and the four half rib cavities are in an interference fit.

2. The industrial ceiling fan blade assembly according to claim 1, characterized in that, The fan blade pad is a profile with two through holes.

Images