阅读说明：本技术 一种用于燃料电池空压机的密封结构 (Sealing structure for fuel cell air compressor ) 是由 靳彩妍 宿明亮 吴孟龙 范俊岩 于 2020-06-28 设计创作，主要内容包括：本发明涉及一种用于燃料电池空压机的密封结构,转轴与压轮背板的接触面上设有两组凹槽,凹槽内设有密封环；压轮与压轮背板之间设有轴向齿式迷宫密封结构。使用时,本发明可用于更高压力差下的气体密封,提高效率和降低能耗,同时轴向齿式迷宫密封结构设计特殊,增加密封效果,另外减小了迷宫设计尺寸对径向轴承间隙的依赖性。(The invention relates to a sealing structure for a fuel cell air compressor, wherein two groups of grooves are arranged on the contact surface of a rotating shaft and a pinch roller back plate, and sealing rings are arranged in the grooves; an axial tooth type labyrinth seal structure is arranged between the pinch roller and the pinch roller back plate. When the axial tooth type labyrinth seal structure is used, the axial tooth type labyrinth seal structure can be used for gas seal under higher pressure difference, the efficiency is improved, the energy consumption is reduced, meanwhile, the axial tooth type labyrinth seal structure is specially designed, the seal effect is improved, and in addition, the dependency of the labyrinth design size on the radial bearing clearance is reduced.)

1. The utility model provides a seal structure for fuel cell air compressor machine, establish in the pivot pinch roller and with pinch roller matched with pinch roller backplate including pivot and cover, its characterized in that: two groups of grooves are arranged on the contact surface of the rotating shaft and the pinch roller back plate, and sealing rings are arranged in the grooves; an axial tooth type labyrinth seal structure is arranged between the pinch roller and the pinch roller back plate.

2. A sealing structure for a fuel cell air compressor according to claim 1, characterized in that: the axial tooth type labyrinth seal structure is composed of a plurality of circles of concentric circles formed by arranging seal teeth, staggered tooth structures of at least more than 5 circles of concentric circles are uniformly distributed on the contact surface of the pinch roller and the pinch roller back plate, and the staggered tooth structures refer to the staggered arrangement of each seal tooth of adjacent concentric circles.

3. A sealing structure for a fuel cell air compressor according to claim 2, characterized in that: the sealing teeth are straight teeth or helical teeth, the end parts of the straight teeth are in an arc shape, and the inclination angle of the helical teeth is 15-30 degrees.

4. A sealing structure for a fuel cell air compressor according to claim 2, characterized in that: the adjacent concentric circles are equally spaced.

5. A sealing structure for a fuel cell air compressor according to claim 2, characterized in that: the distance between adjacent concentric circles is sequentially enlarged from the center of the circle to the outside.

Technical Field

The invention relates to the technical field of air compressors, in particular to a sealing structure for a fuel cell air compressor.

Background

At present, a centrifugal air compressor of a fuel cell adopts an air bearing, cooling air is generally adopted to cool the air bearing and a rotor part of a motor, the cooling air is input into a rotor cavity at a higher pressure, the sealing design of the cooling air is very critical in the process, the existing design is radial labyrinth seal, as shown in figure 1, the structure of the centrifugal air compressor is composed of two parts, one part is a labyrinth tooth type sealing part integrated with a shell or arranged on the shell, the other part is a section of a rotating shaft, in the rotating process, high-pressure gas enters a tooth form in the labyrinth to be depressurized, and the pressure is reduced to the gas pressure at a low-pressure end until the last tooth, so that the function of preventing the high-pressure gas from leaking is completed.

However, the prior art sealing forms have the following disadvantages:

1. because the prior bearing for the fuel cell centrifugal air compressor adopts an air bearing, the clearance design of the labyrinth seal tooth form and the rotating shaft also needs to consider the clearance design of the prior air bearing, so that the rotor system bears the force on the bearing in a static state, the radial bearing clearance is larger than the sealing structure clearance, the radial clearance of the air bearing is larger, and the radial labyrinth seal is designed to be larger than the air bearing clearance, so that the effect of sealing high-pressure gas leakage can not be achieved.

2. Under the condition that the radial labyrinth seal clearance is designed to be small, the sealing effect can reach the standard, but the sealing effect can participate in the motion of the rotor in the form of a spring, so that the cross rigidity is provided for the rotor system, and the stability of the rotor system is influenced.

3. In order to achieve a certain sealing effect, the number of the tooth forms needs to be increased, so that the axial lengthening of the rotor is caused, and the design of rotor dynamics is not facilitated.

Disclosure of Invention

The invention aims to provide a sealing structure of an improved fuel cell air compressor, which can be used for gas sealing under higher pressure difference by adopting a double-sealing ring structure and a pressure wheel back plate labyrinth seal design, thereby improving the efficiency and reducing the energy consumption.

In order to achieve the purpose, the technical scheme of the invention is as follows: the utility model provides a seal structure for fuel cell air compressor machine, establish in the pivot pinch roller and with pinch roller matched with pinch roller backplate including pivot and cover, its characterized in that: two groups of grooves are arranged on the contact surface of the rotating shaft and the pinch roller back plate, and sealing rings are arranged in the grooves; an axial tooth type labyrinth seal structure is arranged between the pinch roller and the pinch roller back plate.

Furthermore, the axial tooth type labyrinth seal structure is composed of a plurality of circles of concentric circles formed by arranging seal teeth, staggered tooth structures of at least more than 5 circles of concentric circles are uniformly distributed on the contact surface of the pinch roller and the pinch roller back plate, and the staggered tooth structures refer to the staggered arrangement of each seal tooth of adjacent concentric circles.

Furthermore, the sealing teeth are straight teeth or helical teeth, the end parts of the straight teeth are in an arc shape, and the inclination angle of the helical teeth is 15-30 degrees.

Further, the spacing between adjacent concentric circles is equal. Or the distance between adjacent concentric circles is sequentially enlarged from the center of the circle to the outside.

Compared with the prior art, the technical scheme of the invention comprises the improvement of a plurality of details besides the improvement of the whole technical scheme, and particularly has the following beneficial effects:

1. according to the improved scheme, two groups of grooves are formed in the contact surface of the rotating shaft and the pinch roller back plate, and sealing rings are arranged in the grooves; an axial tooth type labyrinth seal structure is arranged between the pressing wheel and the pressing wheel back plate, so that the axial tooth type labyrinth seal structure can be used for gas sealing under higher pressure difference, the efficiency is improved, and the energy consumption is reduced;

2. according to the technical scheme, the double-seal ring structure is adopted, so that the axial length of the clearance rotating part is more beneficial to the stability design of a rotor system under the condition of effectively preventing high-pressure gas from leaking;

3. in the scheme of the invention, the axial labyrinth seal design between the pinch roller and the pinch roller back plate is adopted, the labyrinth design area is large, the structure is special, the sealing effect is increased, and in addition, the dependency of the labyrinth design size on the radial bearing clearance is reduced;

4. the invention has simple structure, easy implementation, lower cost and convenient popularization and utilization.

Drawings

Fig. 1 is a schematic structural diagram of the prior art.

Fig. 2 is a schematic structural diagram of the present invention.

Fig. 3 is a partially enlarged schematic view of the present invention.

Reference numerals:

1, a rotating shaft, 2 press wheels and 3 press wheel back plates;

11 grooves and 12 sealing rings;

21 axial tooth type labyrinth sealing structure, 22 sealing tooth.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a sealing structure for a fuel cell air compressor, and particularly relates to a sealing structure for a fuel cell air compressor, which comprises a rotating shaft 1, a pinch roller 2 sleeved on the rotating shaft and a pinch roller back plate 3 matched with the pinch roller, wherein the sealing structure is different from the prior art in that: two groups of grooves 11 are arranged on the contact surface of the rotating shaft and the pinch roller back plate, sealing rings 12 are arranged in the grooves to form a double-sealing ring structure, and an axial tooth type labyrinth sealing structure 21 is arranged between the pinch roller and the pinch roller back plate.

Under the condition of effectively preventing high-pressure gas from leaking, the axial length of the clearance rotating part is more beneficial to the stability design of the rotor system. Meanwhile, the axial labyrinth seal design between the pinch roller and the pinch roller back plate is adopted, the labyrinth design area is large, the sealing effect is improved, and the dependency of the labyrinth design size on the radial bearing clearance is reduced.