A device for testing axial force

Abstract

The present invention relates to the technical field of testing equipment, and in particular to a device for testing axial force, comprising a base, a motor, a PCJJ bearing unit, an S-type tension and pressure sensor, a sensor support seat, and an adjusting screw with a nut; the motor and the sensor support seat are fixed to the top surface of the base, the front end of the motor shaft is connected to the rotating shaft of the pump, and an axial gap is maintained between the rear bearing of the motor shaft and the rear bearing gland, and the PCJJ bearing unit is installed at the rear end of the motor shaft; the front end of the S-type tension and pressure sensor is rotationally connected to the bearing unit gland of the PCJJ bearing unit, and the rear end is rotationally connected to the front end of the adjusting screw, and the rear end of the adjusting screw passes through a through hole provided on the sensor support seat and is then installed with the nut. The present invention can obtain the magnitude of the axial force through experimental testing, thereby providing a reliable data basis for balancing the axial force when designing a pump.

Description

Technical Field

[0001] The invention relates to the technical field of testing equipment, in particular to a device for testing axial force. Background Art

[0002] During the operation of the pump, axial force will inevitably be generated. If the axial force acting on the rotor is not eliminated or balanced, this axial force will pull the rotor to produce axial movement. If the axial movement displacement is too large, the rotor components will contact other parts of the pump and cause damage to the pump parts, seriously affecting the service life of the pump and endangering the life of the operator. Therefore, when designing the pump, it is necessary to evaluate and calculate the size of the pump axial force, and verify the axial force, so as to select a method to balance the axial force according to the size of the measured axial force. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the above-mentioned background technology and to provide a device for testing axial force, which can obtain the magnitude of the axial force through experimental testing, thereby providing reliable data basis for balancing the axial force when designing a pump.

[0004] The technical purpose of the present invention is achieved in this way:

[0005] A device for testing axial force, comprising a base, a motor, a PCJJ bearing unit, an S-type tension and pressure sensor, a sensor support seat, and an adjusting screw with a nut;

[0006] The motor and sensor support seat are fixed on the top surface of the base, the front end of the motor shaft is connected to the rotating shaft of the pump, an axial gap is maintained between the rear bearing of the motor shaft and the rear bearing gland, and the PCJJ bearing unit is installed at the rear end of the motor shaft;

[0007] The front end of the S-type tension and pressure sensor is rotationally connected to the bearing unit cover of the PCJJ bearing unit, and the rear end is rotationally connected to the front end of the adjusting screw. The rear end of the adjusting screw passes through the through hole opened on the sensor support seat and is then installed with the nut.

[0008] According to a further solution, a reduced diameter section is formed at the rear end of the motor shaft, and a shaft shoulder is formed between the reduced diameter section and the shaft section in front of the reduced diameter section. The PCJJ bearing unit is installed on the reduced diameter section, and the front end of the PCJJ bearing unit is limited by the shaft shoulder, and the rear end is limited by the shaft end screw fixed on the rear end surface of the reduced diameter section. The bearing unit cover is fixedly connected to the rear side of the PCJJ bearing unit by bolts.

[0009] In a further solution, the front and rear ends of the S-type tension and pressure sensor are respectively connected with rod end bearings, the front end rod end bearing is rotatably connected to the bearing unit cover through a pin, and the rear end rod end bearing is rotatably connected to a connecting block fixed at the front end of the adjusting screw through a pin.

[0010] In a further solution, the axial clearance between the rear bearing of the motor shaft and the rear bearing gland is greater than the deformation of the S-type tension pressure sensor and smaller than the safety clearance reserved for the pump body and the impeller.

[0011] In a further solution, the rear end of the motor shaft extends from the rear side of the motor housing, passes through the motor hood, and is then installed with the PCJJ bearing unit.

[0012] In a further solution, the motor shaft, the rod end bearing, the S-type tension and pressure sensor and the adjusting screw are arranged coaxially.

[0013] The beneficial effects of the present invention are as follows: the present invention maintains an axial clearance of a safety gap between the bearing of the motor shaft and the bearing cover by changing the size of the bearing cover of the motor shaft, allowing the motor rotor to perform a small range of axial displacement. The axial force originally borne by the bearing can be expressed in the form of displacement. After the pump is running, the axial force borne by the rotor is measured by an S-type tension and pressure sensor connected to the motor shaft, thereby providing a reliable data basis for balancing the axial force when designing the pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a main structural schematic diagram of the present invention.

[0015] Figure 2 yes Figure 1 An enlarged schematic diagram of Part I.

[0016] Figure 3 yes Figure 1 Enlarged schematic diagram of part II.

[0017] Figure 4 This is an enlarged schematic diagram of the rear end of the motor shaft.

[0018] Figure 5 It is a schematic diagram of the working state of the present invention.

[0019] The figure includes: base 1, rear bearing cover 2, motor shaft 3, reduced diameter section 3.1, shaft shoulder 3.2, PCJJ bearing unit 4, shaft end screw 5, bearing unit cover 6, pin 7, rod end bearing 8, S-type tension and pressure sensor 9, connecting block 10, sensor support seat 11, nut 12, adjusting screw 13, motor 14, motor wind cover 14.1, bolt 15, axial clearance 16, rear bearing 17, pump 18. DETAILED DESCRIPTION

[0020] In order to enable ordinary technicians in the field to more clearly understand the objectives, technical solutions and advantages of the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments, but the present invention is not limited to the following embodiments.

[0021] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, a person skilled in the art can understand the specific meanings of general terms in the present invention according to specific circumstances.

[0022] like Figures 1 to 5 As shown, a device for testing axial force provided by the present invention includes a base 1, a motor 14, a PCJJ bearing unit 4, an S-type tension and pressure sensor 9, a sensor support seat 11, and an adjusting screw 13 with a nut 12.

[0023] The motor 14 and the sensor support seat 11 are fixed on the top surface of the base 1. The front end of the motor shaft 3 is connected to the rotating shaft of the pump 18. An axial gap 16 is maintained between the rear bearing 17 of the motor shaft 3 and the rear bearing cover 2. The rear end of the motor shaft 3 extends from the rear side of the motor housing, passes through the motor hood 14.1, and is installed with the PCJJ bearing unit 4. Specifically, the rear end of the motor shaft 3 is formed with a reduced diameter section 3.1, and a shaft shoulder 3.2 is formed between the reduced diameter section 3.1 and the shaft section in front of it. The PCJJ bearing unit 4 is installed on the reduced diameter section 3.1. The front end of the PCJJ bearing unit 4 is limited by the shaft shoulder, and the rear end is limited by the shaft end screw 5 fixed to the rear end surface of the reduced diameter section 3.1. The bearing unit cover 6 is fixedly connected to the rear side of the PCJJ bearing unit 4 by bolts 15.

[0024] The front end of the S-type tension and pressure sensor 9 is rotationally connected to the bearing unit gland 6 of the PCJJ bearing unit 4, and the rear end is rotationally connected to the front end of the adjusting screw 13. The rear end of the adjusting screw 13 passes through the through hole opened on the sensor support seat 11 and is then installed with the nut 12. Specifically, the front end and rear end of the S-type tension and pressure sensor 9 are respectively connected to the rod end bearing 8, the front end rod end bearing 8 is rotationally connected to the bearing unit gland 6 through the pin 7, and the rear end rod end bearing 8 is rotationally connected to the connecting block 10 fixed to the front end of the adjusting screw 13 through the pin 7.

[0025] The motor shaft 3, the rod end bearing 8, the S-type tension and pressure sensor 9 and the adjusting screw 13 are arranged coaxially.

[0026] By calculating the magnitude of the theoretical axial force, estimating the deformation amount generated by the S-type tension pressure sensor 9, and determining the axial size of the bearing gland 2 according to the safety clearance reserved by the pump body and the impeller during design, the axial clearance 16 between the rear bearing gland 2 and the rear bearing 17 is greater than the deformation amount of the S-type tension pressure sensor 9 and less than the safety clearance reserved by the pump body and the impeller, so that the rotor can undergo a small range of axial displacement. The axial force of the pump series within the scope of use of the present invention is relatively small, generally within the range of 2000N, and the safety margin between the pump body and the impeller is 2.5mm. The deformation amount of the S-type tension pressure sensor 9 is much smaller than this value, so the axial clearance between the rear bearing gland 2 and the rear bearing 17 is determined to be 1.7mm in this device.

[0027] Before the test, by adjusting the nut 12 on the adjusting screw 13 connected to the connecting block 10, a preload force opposite to the axial force is applied to the S-type tension and pressure sensor 9, so that the S-type tension and pressure sensor 9 is in a tensioned state, so that the axial force generated by the pump during operation can be measured by the S-type tension and pressure sensor 9, and no excessive axial movement will be generated, so as to ensure that the device provided by the present invention will not be damaged. The main function of applying the preload force is to protect the device provided by the present invention. In theory, as long as it is not greater than the theoretically calculated axial force, it is generally taken about half of the theoretically calculated value during the actual test process.

[0028] The testing steps of the present invention are:

[0029] a. The device provided by the present invention is assembled;

[0030] b. The device provided by the present invention is connected to the pump test type station;

[0031] c. The test equipment and instruments of the water pump test bench are connected to the power supply;

[0032] d. Place the S-type tension and pressure sensor 9 in a stress-free state and set the force control instrument of the water pump test bench to zero;

[0033] e. Adjust the rotor of the motor 14 backward so that the rear bearing 17 is in close contact with the rear bearing gland 2;

[0034] f. Rotate the nut 12 and adjust the screw 13 to apply a preload (half of the theoretical calculated value) to the S-type tension and pressure sensor 9;

[0035] g. Start the pump 18 and run it for a period of time to make the pump in a stable operating state;

[0036] h. Adjust the flow rate through the type table and read the head and axial force values ​​at the required flow point;

[0037] i. Turn off the power supply, loosen the nut 12, and make the S-type tension and pressure sensor 9 in a state without tension and pressure;

[0038] j. Separate the device provided by the present invention from the water pump test bench.

[0039] Comparison table of theoretical calculation and measured data

[0040]

[0041] The mouth ring gap of the prototype used in the test was between 0.05mm and 0.1mm.

[0042] The above is only a preferred embodiment of the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A device for testing axial force, characterized in that: It includes a base (1), a motor (14), a PCJJ bearing unit (4), an S-type tension and pressure sensor (9), a sensor support seat (11), and an adjusting screw (13) with a nut (12); The motor (14) and the sensor support seat (11) are fixed on the top surface of the base (1), the front end of the motor shaft (3) is connected to the rotating shaft of the pump (18), an axial gap (16) is maintained between the rear bearing (17) of the motor shaft (3) and the rear bearing gland (2), and the PCJJ bearing unit (4) is installed at the rear end of the motor shaft (3); The front end of the S-type tension and pressure sensor (9) is rotatably connected to the bearing unit gland (6) of the PCJJ bearing unit (4), and the rear end of the S-type tension and pressure sensor (9) is rotatably connected to the front end of the adjusting screw (13), and the rear end of the adjusting screw (13) passes through a through hole formed on the sensor support seat (11) and is then installed with the nut (12); The rear end of the motor shaft (3) is provided with a reduced diameter section (3.1), a shaft shoulder (3.2) is formed between the reduced diameter section (3.1) and the shaft section in front of it, a PCJJ bearing unit (4) is mounted on the reduced diameter section (3.1), the front end of the PCJJ bearing unit (4) is limited by the shaft shoulder, the rear end of the PCJJ bearing unit (4) is limited by a shaft end screw (5) fixed to the rear end surface of the reduced diameter section (3.1), and the bearing unit gland (6) is fixedly connected to the rear side of the PCJJ bearing unit (4) by bolts (15); The front end and rear end of the S-shaped tension and pressure sensor (9) are respectively connected to rod end bearings (8), the front end rod end bearing (8) is rotatably connected to the bearing unit gland (6) via a pin shaft (7), and the rear end rod end bearing (8) is rotatably connected to a connection block (10) fixed to the front end of the adjusting screw (13) via a pin shaft (7); An axial clearance (16) between the rear bearing (17) of the motor shaft (3) and the rear bearing gland (2) is greater than the deformation of the S-type tension and pressure sensor (9) and smaller than a safety clearance reserved between the pump body and the impeller.

2. A device for testing axial force according to claim 1, characterized in that: The rear end of the motor shaft (3) extends from the rear side of the motor housing, passes through the motor wind shield (14.1), and is then mounted with the PCJJ bearing unit (4).

3. A device for testing axial force according to claim 2, characterized in that: The motor shaft (3), the rod end bearing (8), the S-shaped tension and pressure sensor (9) and the adjusting screw (13) are arranged coaxially.

Images