Multifunctional test bench for engine detection and application

Abstract

The application discloses a multifunctional test bench for engine detection and application, which comprises an engine-side cooling water path, a chilled water-side cooling water path and a heat exchanger, the engine-side cooling water path is communicated with a first passage of the heat exchanger, the chilled water-side cooling water path is communicated with a second passage of the heat exchanger, a to-be-detected engine is connected in the engine-side cooling water path, and temperature acquisition elements, pressure acquisition elements and flow acquisition elements are arranged on the engine-side cooling water path. The multifunctional test bench has simple structure, can be used for engine heat running-in test or engine cylinder cover water jacket blockage detection, can perform 100% full detection on the engine cylinder cover water jacket blockage, does not increase the running-in time of the engine and the production detection personnel, and does not affect the beat of the engine production line.

Description

Technical Field

[0001] This invention relates to engine testing, and more specifically to a multifunctional test bench for engine testing and its applications. Background Technology

[0002] Engines employ a forced-cooling water-cooling structure, with cast water jackets inside the cylinder block and cylinder head. These water jackets remove heat generated by combustion within the cylinder, achieving forced cooling of the engine. With advancements in engine technology, IEM cylinder heads have become the mainstream configuration for major OEMs. The structure of these cylinder heads makes their water jackets more complex, increasing casting difficulty and inspection methods. If problems arise during the casting process, such as issues with the sand core mold leading to the formation of diaphragms, it can cause blockage in the cylinder head water jackets, ultimately manifesting as a cooling system malfunction in the vehicle. Therefore, preventing defective products from reaching the end market has become a crucial aspect of quality assurance.

[0003] Currently, there are three main methods for detecting blockages in cylinder head water jackets. The first is endoscopic inspection, using endoscopic images to confirm whether there are problems such as incomplete sand removal, blockages, or serious casting deviations inside the cylinder head water jacket. The second involves sampling and cutting parts to directly observe the blockage situation in each area. The third is CT scanning of parts to determine the blockage situation inside the cylinder head based on the scan results. The first method is limited by the increasingly complex structure of the water jacket, resulting in blind spots or significantly impacting production cycle time. The second method can only perform batch-based assessments, failing to achieve comprehensive testing, and is a destructive method with high costs. The third method also cannot perform comprehensive testing, severely impacting production cycle time.

[0004] Chinese patent CN201711395024.1 discloses a system and method for detecting the patency of an engine cooling water jacket. This system evaluates whether the flow rate of the cylinder head cooling water jacket deviates from a set or pre-stored flow rate value by controlling pressure difference and flow rate, thereby determining whether the product is blocked. This detection method requires the addition and installation of equipment such as a first pressure sensor, a second pressure sensor, a water tank, a water pump, a control unit, valves, and flow meters, necessitating the addition of a new production and testing workshop, as well as personnel and equipment configuration, inevitably increasing testing costs. Summary of the Invention

[0005] The purpose of this invention is to provide a multifunctional test bench and its application for engine testing. It has a simple structure and can be used for engine hot break-in tests or engine cylinder head water jacket blockage detection.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A multifunctional test bench for engine testing includes an engine-side cooling water circuit, a chilled water-side cooling water circuit, and a heat exchanger. The engine-side cooling water circuit is connected to a first passage of the heat exchanger, and the chilled water-side cooling water circuit is connected to a second passage of the heat exchanger. The engine to be tested is connected to the engine-side cooling water circuit. Temperature acquisition elements, pressure acquisition elements, and flow acquisition elements are arranged on the engine-side cooling water circuit.

[0008] Furthermore, the engine-side cooling water circuit includes an inlet pipe, an intermediate water pipe, an outlet pipe, and a reversing valve. The outlet of the engine under test is connected to one end of the inlet pipe, and the other end of the inlet pipe is connected to the first inlet of the reversing valve. The first outlet of the reversing valve is connected to the inlet of the first passage of the heat exchanger. The outlet of the first passage of the heat exchanger is connected to one end of the outlet pipe, and the other end of the outlet pipe is connected to the inlet of the engine under test. The temperature acquisition element, pressure acquisition element, and flow acquisition element are all installed on the outlet pipe. The intermediate water pipe is connected between the second outlet of the reversing valve and the outlet pipe.

[0009] Furthermore, a regulating valve is connected to the chilled water cooling water line. The second inlet of the regulating valve is connected to the outlet of the second passage of the heat exchanger, the third outlet of the regulating valve and the chilled water outlet are connected to the inlet of the second passage of the heat exchanger, and the fourth outlet of the regulating valve is connected to the chilled water inlet.

[0010] Furthermore, the engine under test is equipped with a pump body connected to the engine-side cooling water circuit, the engine under test has a normally open electronic thermostat at the water outlet, the engine under test has a water temperature sensor at the cylinder head water jacket outlet, and the engine under test has a mechanical thermostat or switch valve at the cylinder block water jacket outlet.

[0011] Furthermore, the temperature acquisition element and the pressure acquisition element are arranged close to the water inlet of the engine under test, and the flow acquisition element is arranged close to the water inlet or outlet of the engine under test.

[0012] The application of the multifunctional test bench for engine testing described in this invention in engine hot break-in testing or engine cylinder head water jacket blockage testing.

[0013] Furthermore, the specific method for detecting engine cylinder head water jacket blockage using the multifunctional test bench for engine testing described in this invention is as follows: connect the engine to be tested to the engine-side cooling water circuit, close the cylinder block water jacket outlet of the engine to be tested, set the operating parameters of the engine to be tested, and allow all the cooling water inside the engine to enter the engine-side cooling water circuit through the cylinder head water jacket outlet of the engine to be tested. Obtain the cooling water flow rate in the engine-side cooling water circuit through the flow acquisition element and compare it with a threshold to determine whether the cylinder head water jacket is blocked.

[0014] The beneficial effects of this invention are as follows: The multifunctional test bench described in this invention can be used for engine hot break-in testing and also for engine cylinder head water jacket blockage detection. It has a simple structure and diverse functions. By monitoring the flow data acquired by the flow acquisition element, it can achieve 100% detection of whether the internal cylinder head water jacket of engines on the production line is blocked, effectively identifying faulty engines and preventing defective engines from entering the market. Furthermore, it does not increase engine break-in time or the number of production and testing personnel, nor does it affect the cycle time of the engine production line. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the multifunctional test bench for engine testing described in this invention.

[0016] Figure 2 This is a diagram showing the flow of coolant inside the engine.

[0017] In the diagram, 1—engine under inspection, 2—inlet pipe, 3—reversing valve, 4—heat exchanger, 5—regulating valve, 6—temperature acquisition element, 7—outlet pipe, 8—pressure acquisition element, 9—intermediate water pipe, 10—flow acquisition element, 11—pump body, 12—cylinder head water jacket, 13—water temperature sensor, 14—electronic thermostat, 15—mechanical thermostat, 16—cylinder block water jacket. Detailed Implementation

[0018] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0019] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0020] See Figure 1The multifunctional test bench shown includes an engine-side cooling water circuit, a chilled water-side cooling water circuit, and a heat exchanger 4. The engine-side cooling water circuit is connected to a first passage of the heat exchanger 4, and the chilled water-side cooling water circuit is connected to a second passage of the heat exchanger 4. The engine under test 1 is connected to the engine-side cooling water circuit. Temperature acquisition element 6, pressure acquisition element 8, and flow acquisition element 10 are arranged on the engine-side cooling water circuit. The temperature acquisition element 6 and pressure acquisition element 8 are arranged near the inlet of the engine under test 1, and are used to monitor the inlet water temperature and inlet water pressure of the engine, respectively. The flow acquisition element 10 is arranged near either the inlet or outlet of the engine under test. In this embodiment, to centrally arrange the various acquisition elements, the flow acquisition element 10 is arranged near the inlet of the engine under test.

[0021] The multifunctional test bench can be used for both engine hot break-in testing and engine cylinder head water jacket blockage detection. During engine hot break-in testing, the engine under test (1) is connected to the engine-side cooling water circuit. Engine operating parameters are set, and the engine's inlet water temperature is monitored by the temperature acquisition element (6). The coolant flow rate in the cooling water circuit is adjusted based on the collected temperature data. The engine's inlet water pressure is monitored by the pressure acquisition element (8) to ensure that the inlet water pressure meets the engine's inlet water pressure requirements.

[0022] When used for detecting blockages in engine cylinder head water jackets, the engine under test 1 is connected to the engine-side cooling water circuit. The outlet of the cylinder block water jacket 16 of the engine under test 1 is closed. The operating parameters of the engine under test 1 are set, and all the cooling water inside the engine under test 1 enters the engine-side cooling water circuit through the outlet of the cylinder head water jacket 12. The flow rate of the cooling water in the engine-side cooling water circuit is acquired by the flow acquisition element 10 and compared with a threshold to determine whether the cylinder head water jacket is blocked. Specifically, when the acquired cooling water flow rate is greater than the threshold, the cylinder head water jacket is determined to be not blocked; when the acquired cooling water flow rate is less than or equal to the threshold, the cylinder head water jacket is determined to be blocked. The multifunctional test bench described in this invention achieves 100% detection of blockages in the internal cylinder head water jackets of engines on the production line, effectively identifying faulty engines and preventing defective engines from entering the market. Furthermore, it does not increase the engine break-in time or the number of production and testing personnel, nor does it affect the cycle time of the engine production line.

[0023] As a preferred embodiment of the present invention, see Figure 1The engine-side cooling water circuit includes an inlet pipe 2, an intermediate water pipe 9, an outlet pipe 7, and a reversing valve 3. The outlet of the engine under test 1 is connected to one end of the inlet pipe 2, and the other end of the inlet pipe 2 is connected to the first inlet a of the reversing valve 3. The first outlet b of the reversing valve 3 is connected to the inlet of the first passage of the heat exchanger 4. The outlet of the first passage of the heat exchanger 4 is connected to one end of the outlet pipe 7, and the other end of the outlet pipe 7 is connected to the inlet of the engine under test 1. The temperature acquisition element 6, the pressure acquisition element 8, and the flow acquisition element 10 are all mounted and fixed on the outlet pipe 7. The intermediate water pipe 9 connects the second outlet c of the reversing valve 3 and the outlet pipe 7. The arrangement of the reversing valve 3 and the intermediate water pipe 9 enables the engine-side cooling water circuit to have a cooling circuit I and a cooling circuit II. Cooling circuit I bypasses the heat exchanger 4 and goes directly from the reversing valve 3 to the inlet of the engine under test 1, ensuring rapid heating of the engine under test and reducing the break-in time. Cooling circuit II, via heat exchanger 4, ensures that the inlet and outlet water temperatures of the engine under test 1 are within the required range. Therefore, cooling circuit I and cooling circuit II are used together during the engine hot break-in test, while cooling circuit II is used during the engine cylinder head water jacket blockage test. The chilled water side cooling water circuit mainly provides cooling water to heat exchanger 4 and cools the cooling water in the engine side cooling water circuit.

[0024] In a preferred embodiment of the present invention, a regulating valve 5 is connected to the chilled water cooling water line. The second inlet d of the regulating valve 5 is connected to the outlet of the second passage of the heat exchanger 4. The third outlet e of the regulating valve 5 and the chilled water outlet are connected to the inlet of the second passage of the heat exchanger 4. The fourth outlet f of the regulating valve 5 is connected to the chilled water inlet. In this embodiment, the regulating valve 5 is a PID regulating valve, which has a compact structure, light weight, high reliability, and maintenance-free sealing.

[0025] As a preferred embodiment of the present invention, see Figure 2 The engine under test 1 is equipped with a pump body 11 connected to the engine-side cooling water circuit. A normally open electronic thermostat 14 is installed at the outlet of the engine under test 1. A water temperature sensor 13 is installed at the outlet of the cylinder head water jacket 12 of the engine under test 1. A mechanical thermostat 15 or a switch valve is installed at the outlet of the cylinder block water jacket 16 of the engine under test 1. Generally, the pump body 11, electronic thermostat 14, water temperature sensor 13, and mechanical thermostat 15 are components integrated into the engine under test 1. Therefore, when conducting engine hot break-in tests or engine cylinder head water jacket blockage detection, there is no need to add an external power source water pump. Using the engine's built-in pump body 11 eliminates the need for additional control units, allowing direct reading of engine speed and outlet water temperature signals with good consistency. No additional production line for engine cooling system on / off and blockage detection is required, saving manpower and material resources.

[0026] Connect the water inlet of the engine under test 1 to the water outlet pipe 7, connect the water outlet of the engine under test 1 to the water inlet pipe 2, and install a male flow acquisition element 10 on the water outlet pipe 7 near the water inlet of the engine 1. The cylinder head water jacket blockage can be detected by using the cooling circuit II of the cooling system.

[0027] During specific testing, based on the opening characteristics of the mechanical thermostat 15, such as an initial opening temperature of 100℃ and a fully open temperature of 110℃, when the cooling system coolant temperature is below 100℃, the mechanical thermostat 15 at the outlet of the cylinder block water jacket 16 does not open. The coolant in the entire cooling system only flows into the cylinder head water jacket 12, and then through the cylinder head water jacket 12 into the electronic thermostat 14 at the outlet of the engine under test 1. In this state, the ECU controls the electronic thermostat at the outlet of the engine under test 1 to be fully open. That is, the coolant inside the engine under test 1 is powered by the pump body 11 and flows only into the cylinder head water jacket 12, then through the electronic thermostat 14 at the outlet of the engine under test 1 to the reversing valve 3. When detecting blockage in the cylinder head water jacket of the engine under test, the cooling water temperature in the engine-side cooling water circuit is set to 80℃, the mechanical thermostat 15 at the outlet of the cylinder block water jacket 16 is not turned on, the engine under test 1 is set to a fixed speed, and all the cooling water inside the engine under test 1 flows through the cylinder head water jacket 12 into the normally open electronic thermostat 14 at the outlet of the engine under test 1 and then flows back to the reversing valve 3. At this time, when the cooling water flow rate is lower than the threshold value, i.e. the qualified product setting value, it is determined that the cylinder head water jacket of the engine under test is abnormally blocked.

[0028] For the engine 1 under test that lacks a mechanical thermostat 15 at the outlet of the cylinder block water jacket 16, a switching valve needs to be added at the outlet of the cylinder block water jacket 16. This valve is closed during cylinder head water jacket blockage testing, allowing coolant in the entire engine-side cooling water circuit to flow only into the cylinder head water jacket 12, and then into the electronic thermostat 14 located at the outlet of the engine 1 under test. In this state, the ECU controls the electronic thermostat 14 to be fully open, meaning the coolant inside the engine 1 under test is powered by the pump body 11 and flows only into the cylinder head water jacket 12, then through the electronic thermostat 14 to the reversing valve 3. When the coolant flow rate is lower than the set value for qualified products, the cylinder head water jacket of the engine under test is determined to be abnormally blocked.

[0029] When the outlet of the engine under test 1 is equipped with a mechanical thermostat 15, ECU control is not required. It is only necessary to set the outlet water temperature of the cylinder head water jacket 12 to be lower than the off-temperature of the mechanical thermostat 15 according to the opening characteristics of the mechanical thermostat 15. For example, if the off-temperature of the mechanical thermostat is 100℃, the outlet water temperature of the engine under test 1 is set to be <100℃. This temperature is read by the water temperature sensor 13 set at the outlet of the cylinder head water jacket 12 of the engine under test. The above scheme can also be used to detect whether the cylinder head water jacket is blocked.

[0030] The above embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention.

Claims

1. A multifunctional test bench for engine testing, characterized in that: It includes an engine-side cooling water circuit, a chilled water-side cooling water circuit, and a heat exchanger (4). The engine-side cooling water circuit is connected to the first passage of the heat exchanger (4), and the chilled water-side cooling water circuit is connected to the second passage of the heat exchanger (4). The engine to be tested (1) is connected to the engine-side cooling water circuit. Temperature acquisition element (6), pressure acquisition element (8), and flow acquisition element (10) are arranged on the engine-side cooling water circuit. The engine-side cooling water circuit includes an inlet pipe (2), an intermediate water pipe (9), an outlet pipe (7), and a reversing valve (3). The outlet of the engine (1) under test is connected to one end of the inlet pipe (2), and the other end of the inlet pipe (2) is connected to the first inlet of the reversing valve (3). The first outlet of the reversing valve (3) is connected to the inlet of the first passage of the heat exchanger (4). The outlet of the first passage of the heat exchanger (4) is connected to one end of the outlet pipe (7), and the other end of the outlet pipe (7) is connected to the inlet of the engine (1) under test. The temperature acquisition element (6), pressure acquisition element (8) and flow acquisition element (10) are all installed on the outlet pipe (7), and the intermediate water pipe (9) is connected between the second outlet of the reversing valve (3) and the outlet pipe (7).

2. The multifunctional test bench for engine testing according to claim 1, characterized in that: A regulating valve (5) is connected to the cooling water line on the chilled water side. The second inlet of the regulating valve (5) is connected to the outlet of the second passage of the heat exchanger (4). The third outlet of the regulating valve (5) and the chilled water outlet are connected to the inlet of the second passage of the heat exchanger (4). The fourth outlet of the regulating valve (5) is connected to the chilled water inlet.

3. The multifunctional test bench for engine testing according to claim 1, characterized in that: The engine under test (1) is equipped with a pump body (11) connected to the engine side cooling water circuit. The outlet of the engine under test (1) is equipped with a normally open electronic thermostat (14). The outlet of the cylinder head water jacket (12) of the engine under test (1) is equipped with a water temperature sensor (13). The outlet of the cylinder block water jacket (16) of the engine under test (1) is equipped with a mechanical thermostat (15) or a switch valve.

4. The multifunctional test bench for engine testing according to claim 1, characterized in that: The temperature acquisition element (6) and the pressure acquisition element (8) are arranged near the water inlet of the engine (1) under test, and the flow acquisition element (10) is arranged near the water inlet or outlet of the engine (1) under test.

5. The application of the multifunctional test bench for engine testing as described in any one of claims 1 to 4 in engine hot break-in tests or engine cylinder head water jacket blockage tests.

6. The application according to claim 5, characterized in that, The engine cylinder head water jacket blockage detection is performed using the multifunctional test bench for engine testing as described in any one of claims 1 to 4 as follows: the engine to be tested (1) is connected to the engine-side cooling water circuit, the cylinder block water jacket (16) outlet of the engine to be tested (1) is closed, the operating parameters of the engine to be tested (1) are set, and all the cooling water inside the engine to be tested (1) enters the engine-side cooling water circuit through the cylinder head water jacket (12) outlet of the engine to be tested (1). The cooling water flow rate in the engine-side cooling water circuit is obtained by the flow acquisition element (10) and compared with the threshold to determine whether the cylinder head water jacket is blocked.

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