QC/T 1147-2021Electronic silicon oil fan clutch for vehicle engine (English PDF)

3.25 Closed-loop speed feature

When the target speed of the fan clutch is constant, AND the different input speeds are set, the performance of the control system, to control the output speed to gradually approaches to the target output speed, by making the fan clutch be in the disengaged status, through automatic adjustment of pulse width modulation signal, based on the feedback from the output speed.

4.1 General requirements

4.1.1 Processing and casting

The fan clutch shall be manufactured, in accordance with the approved product drawings and technical documents. The surface of the fan clutch casting is smooth. There must be no defect, such as blisters, shrinkage, cracks, etc. It shall meet the requirements of QC/T 747-2006 or drawings and related technical conditions.

4.1.2 Working voltage of coil

The working voltage of the fan clutch's coil shall generally be 24V ± 4V and 12V ± 2V; OR it shall meet the requirements of the drawing and related technical conditions.

4.1.3 Working voltage of Hall speed sensor

The working voltage of the fan clutch's Hall speed sensor shall generally be 3.8V ~ 24V; OR it shall meet the requirements of the drawing and related technical conditions.

4.1.4 Working frequency of pulse width modulation signal

The working frequency of the pulse width modulation signal of the fan clutch shall generally be 1Hz ~ 10Hz; OR it shall meet the requirements of the drawings and related technical conditions.

4.1.5 Working environment temperature

The working environment temperature of the fan clutch shall be -41°C ~ 125°C; OR it shall meet the requirements of drawings and related technical conditions.

4.1.6 Cleanliness

The cleanliness in the working chamber of the fan clutch shall meet the requirements of QC/T 572-1999 or drawings and related technical documents.

4.1.7 Dynamic balance

The dynamic balance performance of the rotating parts of the fan clutch shall meet the requirements of QC/T 747-2006 or drawings and related technical documents.

4.1.8 Main bearing seal

When tested according to the requirements of 5.1, the sealing performance of the main bearing of the fan clutch shall meet the requirements of QC/T 747-2006 or drawings and related technical documents.

4.2 Performance requirements

4.2.1 Open-loop performance

4.2.1.1 Response feature

a) Engaged response feature

Carry out the test in accordance with clause 5.2.5.1. The open-loop engaged response feature of the fan clutch shall meet the requirements of the drawing and related technical conditions. In general, the engaged response time of the fan clutch shall be not more than 18s; the fully engaged speed slip rate shall be not more than 8%.

b) Disengaged response feature

Perform the test in accordance with clause 5.2.5.1. The open-loop disengaged response feature of the fan clutch shall meet the requirements of the drawing and related technical conditions. Under normal circumstances, when the input speed is 1000r/min, the disengaged response time of the fan clutch shall be not more than 260s; the fully disengaged speed shall be less than 450r/min.

4.2.1.2 Pulse width modulation feature

Carry out the test in accordance with clause 5.2.5.2. The open-loop pulse width modulation feature of the fan clutch shall meet the requirements of the drawing and relevant technical conditions. Under normal circumstances, the start rising speed for the engagement of the fan clutch shall not exceed 500r/min;

4.3.4 Voltage ramp-down and ramp-up performance

Perform the test in accordance with clause 5.3.4. The voltage ramp-down and ramp-up performance of fan clutch shall reach the supply voltage range, in Table 1 and Table 2, as well as the level D, which is defined in GB/T 28046.1-2011.

4.3.5 Voltage transient change performance

The test is carried out in accordance with clause 5.3.5. The performance of the transient change of the power supply voltage of the fan clutch shall reach the level B, which is defined in GB/T 28046.1-2011.

4.3.6 Reverse voltage performance

Perform the test in accordance with clause 5.3.6. The reverse voltage performance of the fan clutch shall reach the level C, which is defined in GB/T 28046.1-2011.

4.4 Electromagnetic immunity performance

Perform the test in accordance with clause 5.4. The electromagnetic immunity performance of the fan clutch shall meet the requirements of the drawing and related technical conditions.

4.5 Reliability

4.5.1 Durability of bench

Perform the test in accordance with clause 5.5.1. After the test, the fan clutch shall have no oil leakage; the labyrinth groove has no scratch; the silicone oil has no discoloration or deterioration; the bearing has no jamming; the parts have no damage or deformation; the fasteners have no loosening; the insulation status of the power cable's connection points and conductors shall be intact; the performance of the fan clutch shall meet the requirements of clause 4.2.

4.5.2 High and low temperature performance

Perform the test in accordance with clause 5.5.2. After the test, the fan clutch shall have no oil leakage; the silicone oil has no discoloration or deterioration; the bearing has no jamming; the parts have no damage or deformation; the fasteners have no loosening; the non-metallic parts are not aged; the insulation status of the power cable's connection points and conductors shall be intact; the performance of the fan clutch shall meet the requirements of clause 4.2.

4.5.3 Corrosion resistance

Carry out the test in accordance with clause 5.5.3. After the test, the surface corrosion of the metal parts of the fan clutch shall meet the requirements of the drawing and relevant technical conditions.

4.5.4 Vibration resistance

Carry out the test in accordance with clause 5.5.4. After the test, the fan clutch shall have no oil leakage; the bearing has no jamming; the labyrinth groove has no scratch; the parts have no damage or deformation; the fasteners have no loosening; the insulation status of the power cable's connection points and conductors shall be intact; the performance of the fan clutch shall meet the requirements of clause 4.2.

4.5.5 Strength performance of coil's lead-out wire harness

Perform the test in accordance with clause 5.5.5. After the test, the wiring harness shall be free of damage; the non-metallic parts shall be free of cracks or deformations; the connection points shall be firm; the conductor's insulation status is intact; the performance shall meet the requirements of the drawing or related technical documents.

5.1 Sealing performance test of main bearing

5.1.1 Sealing performance test at normal temperature

The test shall be carried out, in accordance with 6.1.1 of QC/T 33-2006.

5.1.2 High and low temperature sealing performance test

The test shall be carried out, in accordance with 6.1.2 of QC/T 33-2006.

5.2 Performance test

5.2.1 Environmental conditions

The test environment temperature shall be 25°C ~ 90°C. The temperature shall be controlled at the set temperature ±5°C. The relative humidity is 25%RH ~ 85%RH. The atmospheric pressure is 86kPa ~ 106kPa. If there are other requirements, they can be implemented, according to the drawings or relevant technical documents.

5.4 Electromagnetic radiation immunity test

The electromagnetic radiation immunity test shall be carried out, according to the high current injection method AND the free field method, respectively. The frequency of the high current injection method is 1MHz ~ 400MHz. The frequency of the free field method is 200MHz ~ 2.5GHz and 2.7 GHz ~ 3.2GHz.

According to GB/T 17619-1998, use the large current injection method to carry out test. The current size is in accordance with the requirements of the technical documents. The free field method test shall be carried out, in accordance with GB/T 17619-1998; the electric field strength shall be in accordance with the requirements of the technical documents.

5.5 Reliability test

5.5.1 Bench durability test

The fan clutch and fan assembly, that have passed the performance test, shall be installed on the reliability test bench, at room temperature. Add a gasket, between the input flange of the clutch and the output flange of the test bench, to make the end face runout of 0.15mm ~ 0.2mm, at a position of 100mm rotating diameter of the fan clutch's input end flange, OR set the end face runout, according to the relevant technical documents.

Set the input speed of the fan clutch, the pulse width modulation signal, the working frequency of pulse width modulation signal. The input speed is determined, based on specific working conditions. The pulse width modulation signal is determined, according to the engaged and disengaged status of the fan clutch, in each test working condition. The speed, under the specific working condition, is generally the input speed of the fan clutch, which is corresponding to the rated working condition of the engine. 1 cycle is composed of 7 working conditions, each cycle is 1h, for a total of 500h. Refer to Figure 8 -- Schematic diagram of the durability performance test curve of the fan clutch bench, AND Table 2 -- Durability performance test table of the fan clutch bench.

6.2 Exit-factory inspection

Products can only leave the factory, after they pass the inspection by the quality inspection department of the manufacturer, AND being attached with the product quality qualification documents.

6.3 Type inspection

Type inspection is required for products in the following situations:

a) When the new product is type finalized AND the old product is subject to trans-plant production;

b) When materials and processes have undergone major changes;

c) When the production is restored after suspension for more than 1 year;

d) During normal production, it is performed once a year, OR as agreed between the supplier and the buyer.

7.1 Marking

The marking position, size, method of products and packaging shall be implemented, in accordance with the requirements of drawings or related technical documents.

7.1.1 Product marking

a) The manufacturer's logo or trademark;

b) Product drawing number;

c) Production flow code;

d) Date of production.

7.1.2 Packaging mark

a) Manufacturer and address;

b) Product name and code;