CN114310149A

CN114310149A - Tool and method for accurately controlling end face clearance of hydrogen circulating pump

Info

Publication number: CN114310149A
Application number: CN202111549808.1A
Authority: CN
Inventors: 冯健美; 张兆君; 孔祥程; 彭学院
Original assignee: Xian Jiaotong University
Current assignee: Xian Jiaotong University
Priority date: 2021-12-17
Filing date: 2021-12-17
Publication date: 2022-04-12
Anticipated expiration: 2041-12-17
Also published as: CN114310149B

Abstract

The application discloses a tool and a method for accurately controlling the end face clearance of a hydrogen circulating pump, and relates to the technical field of hydrogen circulating pumps. Including frock board, first bolt, nut and respectively with two screw hole matched with second bolt and third bolt on the rotor, wherein: the tooling plate is provided with a first limiting hole and two second limiting holes at positions corresponding to the shaft hole and the two threaded holes of the rotor, and the first bolt, the second bolt and the third bolt respectively penetrate through the first limiting hole and the two second limiting holes; the screw thread on first bolt and the nut is fine and close screw thread, and the cooperation is connect soon with the nut after the one end of first bolt passes first spacing hole, and the external diameter of first bolt is less than the aperture in rotor shaft hole. The method is used for accurately controlling the end face clearance of the hydrogen circulating pump.

Description

Tool and method for accurately controlling end face clearance of hydrogen circulating pump

Technical Field

The application relates to the technical field of hydrogen circulating pumps, in particular to a tool and a method for accurately controlling end face clearance of a hydrogen circulating pump.

Background

The hydrogen circulating pump is one of the core components of the hydrogen fuel cell automobile technology, and has special requirements on the performance and the use environment of the pump, so that the hydrogen circulating pump has a plurality of technical difficulties to be solved. In order to ensure that the exchange membrane fuel cell has better comprehensive performance, the air supply subsystem is required to be capable of adjusting the air supply quantity and the air supply pressure in time according to the output power of the fuel cell, and the fuel cell has the characteristics of compact structure, light weight, low noise, high reliability, recoverable energy and the like. The relative rotation between the two rotors of the claw pump is realized by the synchronous gear, and the two rotors do not contact with each other, so that the oil-free transmission of working media can be realized to ensure the cleanliness of the working media; the quick-wear parts such as an air suction valve and an air exhaust valve are not needed, so that the operation is reliable and the structure is simple; through the reasonable design of the air suction port and the air exhaust port, the claw type pump has a certain internal compression process; the flow regulating device has flow regulating capacity, and the backflow capacity of the flow regulating device can respond to different powers. In summary, the claw pump can be regarded as an ideal structural form of the hydrogen circulation pump.

While claw pumps have many excellent characteristics, clearance control has been a difficulty. The clearance not only determines the reliability of the hydrogen circulation pump, but also directly determines the performance of the hydrogen circulation pump. The clearances of the claw pump are divided into three types: end face clearance, tooth crest clearance, and tooth space clearance. The end face clearance is the distance between the rotor and the end face; the tooth top clearance is the distance between the rotor and the top of the cylinder; the tooth space clearance is the meshing distance between the rotors. The end face gap is the most important ring, and the influence on the performance is the largest in three gaps, so the control of the end face gap is particularly important. At present, the precision requirement of the end face clearance reaches 0.01mm, a feeler gauge is arranged between a rotor and the end face in the traditional control method, but the method has a lot of uncertainty, for example, the flatness of the feeler gauge influences the size of the end face clearance; for example, oil adhered to the feeler is difficult to clean after the rotor is installed, and exhaust gas contains oil in the subsequent operation process, so that a fuel cell system is polluted. The net result of this approach is that the actual gap tends to be larger than the caliper thickness and the gap is irregular, resulting in a set-up power. Under the condition of unsuccessful one-time assembly, the rotor can only be pulled out and assembled again, but the rotor is made of aluminum and has lower hardness than the rotating shaft, and the inner hole of the rotor can be damaged in the process of pulling out the rotor, so that the interference magnitude of the rotor is reduced; further causing the rotor and the rotating shaft to slide in the subsequent operation process, and reducing the safety and the reliability of the hydrogen circulating pump. At present, no good method for accurately controlling the end face clearance is available.

Disclosure of Invention

The application provides a tool and a method for accurately controlling the end face clearance of a hydrogen circulating pump, the tool formed by a tool plate, a first bolt, a nut, a second bolt and a third bolt is used for accurately controlling the end face clearance, the defect of unsuccessful assembly is avoided, and the assembly and control difficulty is simplified.

In order to achieve the above object, in one aspect, the present application provides a tooling for accurately controlling the end face clearance of a hydrogen circulation pump, which comprises a tooling plate, a first bolt, a nut, and a second bolt and a third bolt respectively matched with two threaded holes on a rotor, wherein:

the tooling plate is provided with a first limiting hole and two second limiting holes at positions corresponding to the shaft hole and the two threaded holes of the rotor, and a first bolt, a second bolt and a third bolt respectively penetrate through the first limiting hole and the two second limiting holes;

the screw thread on first bolt and the nut is fine and close screw thread, the cooperation of connecing soon with the nut after the one end of first bolt passes first spacing hole, the external diameter of first bolt is less than the aperture in rotor shaft hole.

Further, the thread pitch of the first bolt is 0.06 mm.

Further, the first bolt and the second bolt are both hexagon socket head cap bolts.

On the other hand, the application also provides a method for accurately controlling the end face clearance, which is realized based on the tool and comprises the following steps:

step 1: the rotor is arranged on the end surface of the hydrogen circulating pump in a hot mode;

step 2: heating the rotor again, screwing the second bolt and the third bolt into the two threaded holes of the rotor respectively after heating is finished, abutting the first bolt against a rotating shaft of the hydrogen circulating pump, and screwing the nut upwards to finish installation;

and step 3: firstly, clamping a nut by using one wrench, and then clockwise pulling a first bolt by using the other wrench until the first bolt rotates to a preset rotation angle, and stopping operation, wherein the rotor is lifted along with the rotation of the first bolt in the process; the preset rotation angle is obtained by calculation according to the target end face gap and the thread pitch of the first threads;

and 4, step 4: and (5) when the rotor and the hydrogen circulating pump are completely cooled, disassembling the assembly tool, and obtaining the target end face clearance.

Further, step 2 further comprises: a feeler gauge with the same height as the gap height of the target end face is abutted against the edge of the rotor;

step 3 also includes: the operation is stopped at the moment when the feeler enters the end face gap.

Further, in the step of reheating the rotor, the heat source is located on the side of the rotor away from the hydrogen circulation pump.

Further, the heating temperature is less than 120 ℃.

Compared with the prior art, the application has the following beneficial effects: the tool and the assembling method further accurately control the end face clearance, can accurately reach the target clearance, and improve the performance of the hydrogen circulating pump. The application also simplifies the assembly and control difficulty, improves the assembly precision and success rate, and can enable the end face clearance to achieve the expected effect. The stability and the efficiency of the operation of the hydrogen circulating pump are improved.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic structural view of a tool in embodiment 1 of the present application;

FIG. 2 is a top view of the tool of example 2 of the present application after assembly;

FIG. 3 is an assembly view of the tool in embodiment 1 of the present application;

fig. 4 is a flowchart of a method of controlling an end face gap according to embodiment 2 of the present application;

FIG. 5 is a schematic structural view of a hydrogen circulation pump before a rotor is installed in embodiment 2 of the present application;

FIG. 6 is a schematic view of a rotor after being hot-assembled according to embodiment 2 of the present application;

FIG. 7 is a schematic view showing the heating of the rotor in example 2 of the present application;

fig. 8 is a schematic diagram of backlash control in embodiment 2 of the present application.

In the figure, 1-hydrogen circulating pump, 2-rotor, 3-tooling plate, 4-first bolt, 5-nut, 6-second bolt, 7-third bolt and 8-heat source.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. 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 application.

In the description of the present application, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be construed as limiting the present application.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; the specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless otherwise specified.

Referring to fig. 1 and 3, embodiment 1 of the present application provides a tool for accurately controlling an end surface gap of a hydrogen circulation pump, where the tool can control end surface gaps of the hydrogen circulation pump 1 and a rotor 2. The tool comprises a tool plate 3, a first bolt 4, a nut 5, and a second bolt 6 and a third bolt 7 which are respectively matched with two threaded holes in the rotor 2. The tooling plate 3 is provided with a first limiting hole for the first bolt 4 to pass through at a position corresponding to the shaft hole of the rotor 2, and the tooling plate 3 is provided with two second limiting holes for the second bolt 6 and the third bolt 7 to pass through respectively at positions corresponding to the two threaded holes of the rotor 2. One end of the first bolt 4 penetrates through the first limiting hole and then is in screwed connection with the nut 5, and the outer diameter of the first bolt 4 is smaller than the aperture of the shaft hole of the rotor 2.

The thread pitch of the first bolt 4 is 0.06mm, and the bolt will axially displace 0.06mm when rotating for each circle, so the rotating angle is controlled, and the gap of 0.01mm grade can be accurately controlled. The first bolt 4, the second bolt 6, and the third bolt 7 may be, but are not limited to, hexagon socket head cap bolts.

The working principle of the embodiment 1 of the application is as follows: when using assembly fixture control terminal surface clearance, earlier with second bolt 6, in the screw hole of third bolt 7 precession rotor 2, support first bolt 4 again on the axle, and upwards screw nut 5, second bolt 6 this moment, third bolt 7, rotor 2, nut 5, frock board 3 is connected as an organic wholely, reuse spanner block nut 5, under such a condition, first bolt 4 can radial movement, along with interior first bolt 4's rotation, rotor 2 can be by slow lifting, second bolt 6, the displacement that third bolt 7 and first bolt 4 take place is the clearance of lifting promptly. When the installation is carried out, the tooling plate 3 is ensured to be horizontal, so that the force is uniformly applied to the rotor 2 when the gap is subsequently controlled. The thread pitch of the first bolt 4 is 0.06mm, and the first bolt 4 can radially displace 0.06mm when rotating once, so that the elevation of 0.01mm only needs to rotate 60 degrees. The nut 5 is likewise a specially made nut 5, the purpose of which is to fit a first bolt 4 with a thread pitch of 0.06 mm.

Referring to fig. 2 and 4-8, an embodiment of the present application provides an assembling method of a hydrogen circulation pump for a fuel cell, including the following steps:

step 1: the rotor 2 was hot-fitted on the end face of the hydrogen circulation pump 1 with an end face clearance of 0.

Step 2: the rotor 2 is heated again, the heating temperature is 120 ℃, and the heat source 8 is positioned at one side of the rotor 2 far away from the hydrogen circulating pump 1. After heating is finished, the second bolt 6 and the third bolt 7 are screwed into two threaded holes of the rotor 2 respectively, so that the second bolt 6 and the third bolt 7 are fixed with the rotor 2; and then the first bolt 4 is abutted against the rotating shaft of the hydrogen circulating pump 1, and the nut 5 is screwed upwards to finish the installation. The level of the tooling plate 3 is required to be ensured during installation, so that the assembly tooling can apply force to the rotor 2 uniformly during subsequent clearance control.

After the rotor 2 is provided with the hydrogen circulating pump 1, the end surface gap is almost zero. At the moment, the rotor 2 is in direct contact with the hydrogen circulating pump 1, heat is transferred to the pump body through the shaft, the temperature of the rotor 2 is rapidly reduced, so that an inner hole of the rotor 2 is contracted when meeting cold, and the rotor and the shaft of the hydrogen circulating pump 1 are in interference fit. Thus, in order to re-expand the bore and reduce the damage to the bore during subsequent clearance control, the rotor 2 needs to be reheated. Reheating the rotor 2 reduces the interference magnitude between the rotor 2 and the shaft, so that the inner hole and the shaft tend to be in transition fit, and prepares for controlling the clearance later, so that the clearance control process is linear sliding. The temperature of 120 ℃ is the safe temperature of the common shaft seal made of the fluororubber, and the shaft seal made of the fluororubber can be ensured not to be damaged at the temperature.

And step 3: firstly, clamping the nut 5 by using one wrench, and then clockwise pulling the first bolt 4 by using the other wrench until the first bolt 4 rotates to a preset rotation angle, and stopping operation, wherein the rotor 2 is lifted along with the rotation of the first bolt 4 in the process; the preset rotation angle is calculated according to the target end face clearance and the thread pitch of the first bolt 4. In step 2, the second bolt 6, the third bolt 7, the nut 5 and the tooling plate 3 are connected into a whole, and the first bolt 4 abuts on the shaft, so that when the nut 5 is clamped by a wrench and the first bolt 4 is rotated clockwise, the rotor 2 is lifted upwards along with the rotation of the first bolt 4.

In this embodiment, the target end face gap is 0.05mm, the pitch of the first bolt 4 is 0.06mm, and the first bolt is lifted by 0.06mm in one turn, so that the rotor 2 can be lifted by 0.05mm only by rotating 300 ° because the first bolt is lifted by 0.05 mm.

And 4, step 4: and (3) when the rotor 2 and the hydrogen circulating pump 1 are completely cooled, disassembling the assembly tool, and obtaining the target end face clearance.

In order to verify the accuracy of the target gap control, step 2 further comprises the steps of: a feeler gauge with the same height as the target end surface gap is pressed against the edge of the rotor 2, namely the feeler gauge is pressed against the position of the end surface gap of 0; step 3 also includes: and stopping operation after the feeler enters the end face.

The method is suitable for the hydrogen circulating pump 1 in the forms of Roots, claw type and the like, the clearance accuracy controlled by the method and the tool is high, the stability and the reliability of the operation of the hydrogen circulating pump 1 are ensured, any target clearance can be obtained, the problem that the clearance of the upper end face on the market is difficult to control at present is solved, the effect of accurate assembly is achieved, the performance of the hydrogen circulating pump 1 is directly influenced by the clearance of the end face, and the volumetric efficiency of the hydrogen circulating pump 1 with small clearance is greatly improved compared with that of the hydrogen circulating pump 1 with large clearance. The rotor 2 is heated before the clearance is controlled, the inner hole is enlarged, so that the inner hole of the rotor 2 and the shaft tend to be in transition fit, and the inner hole of the rotor 2 can not be damaged when the clearance is controlled. Meanwhile, the heating temperature is selected from the safe temperature of the pump body, so that the heating only affects the rotor 2 and does not affect the pump body. Finally, the purposes of reducing cost and improving assembly efficiency are achieved.

The above is only an embodiment of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions within the technical scope of the present disclosure should be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. The utility model provides a frock for end face clearance of accurate control hydrogen circulating pump which characterized in that, including frock board, first bolt, nut and respectively with two screw hole matched with second bolt and third bolt on the rotor, wherein:

2. The tool for accurately controlling the end face clearance of the hydrogen circulation pump according to claim 1, wherein the pitch of the first bolt is 0.06 mm.

3. The tool for accurately controlling the end face clearance of the hydrogen circulation pump according to claim 1, wherein the first bolt and the second bolt are both hexagon socket head bolts.

4. A method for accurately controlling the end face clearance, which is realized based on the tool for accurately controlling the end face clearance of the hydrogen circulation pump according to any one of claims 1 to 3, and comprises the following steps:

5. The method of claim 4, wherein step 2 further comprises: a feeler gauge with the same height as the gap height of the target end face is abutted against the edge of the rotor;

6. A method of accurately controlling end face clearance according to claim 4 or 5, wherein in the step of reheating the rotor in step 2, the heat source is located on the side of the rotor remote from the hydrogen circulation pump.

7. A method of accurately controlling the clearance between the end faces of the roller and the roller as claimed in claim 6, wherein the heating temperature is less than 120 ℃.