Engine In-cylinder Intake Negative Pressure Measuring Device and Method

Abstract

The present invention relates to the technical field of pressure detection, and provides an in-cylinder intake negative pressure measurement device and method for an engine, including a valve, a pressure detection element, a data acquisition system, an intake detection element and a controller. The inlet of the valve is communicated with the cylinder block of the engine, and the pressure detection element is communicated with the outlet of the valve; the data acquisition system is communicatively connected with the pressure detection element; the intake detection element is used to detect the opening and closing of the valve of the cylinder block; the controller is communicatively connected with the valve and the intake detection element respectively, and the controller controls the opening and closing of the valve according to the detection signal of the intake detection element. It can directly measure the negative pressure in the cylinder of the engine without indirect measurement or analog calculation after indirect measurement. Its measurement result only contains the data of the engine intake stroke, which is convenient for analyzing the measurement result; a common negative pressure sensor can be used to measure the negative pressure in the cylinder during intake, which can improve the measurement accuracy and does not require a specially customized sensor, which is beneficial to reducing the measurement cost.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure detection, and particularly relates to an in-cylinder intake negative pressure measurement device and method for an engine. Background Art

[0002] Currently, with the upgrading of engine emissions and the reduction of fuel consumption, and in addition, the engine after-treatment SCR system requires a relatively high exhaust gas temperature. Therefore, each engine has an engine thermal management system, which aims to increase the exhaust gas temperature under medium and low engine loads to meet the working conditions of the SCR system. Among the common methods, a TVA valve is set in front of the intake manifold of the engine to control the intake air flow of the engine, effectively control the air-fuel ratio, and perform thermal management. However, the application of the intake TVA valve will inevitably cause an increase in the negative pressure in the engine cylinder under medium and low engine loads, and the increase in negative pressure will cause the engine oil in the crankcase to be sucked above the piston, thereby increasing the engine oil consumption. Therefore, reasonably controlling the magnitude of the in-cylinder negative pressure of the engine becomes one of the key factors for controlling the engine oil consumption.

[0003] In the prior art, when the engine intakes air, the in-cylinder negative pressure is relatively small, only dozens of kilopascals, while when the engine ignites, the explosion pressure reaches about 200 bar. Ordinary negative pressure sensors cannot withstand such a high explosion pressure, and under the engine ignition condition, ordinary pressure sensors also cannot withstand the high temperature in the engine cylinder. Summary of the Invention

[0004] The present invention provides an in-cylinder intake negative pressure measurement device and method for an engine to solve the defect that ordinary negative pressure sensors in the prior art cannot measure the in-cylinder intake negative pressure.

[0005] The present invention provides an in-cylinder intake negative pressure measurement device for an engine, including:

[0006] A valve, the inlet of which is communicated with the cylinder block of the engine;

[0007] A pressure detection element, which is communicated with the outlet of the valve;

[0008] A data acquisition system, which is communicatively connected with the pressure detection element;

[0009] An intake detection element, which is used to detect the opening and closing of the valve of the cylinder block;

[0010] A controller, which is communicatively connected with the valve and the intake detection element, and the controller controls the opening and closing of the valve according to the detection signal of the intake detection element.

[0011] According to the in-cylinder intake negative pressure measurement device for an engine provided by the present invention, it further includes:

[0012] A connection channel is provided on the cylinder head of the cylinder block. The first end of the connection channel communicates with the combustion chamber of the cylinder block, and the second end of the connection channel communicates with the inlet of the valve.

[0013] An in-cylinder intake negative pressure measuring device for an engine according to the present invention, wherein the intake detection element is used to detect the position of the intake rocker arm of the engine. When the intake rocker arm is in the first position, the valve is in the closed state; when the intake rocker arm is in the second position, the valve is in the open state.

[0014] An in-cylinder intake negative pressure measuring device for an engine according to the present invention, wherein the intake detection element is arranged above the roller of the intake rocker arm, and when the intake rocker arm is in the second position, the intake detection element is triggered.

[0015] An in-cylinder intake negative pressure measuring device for an engine according to the present invention further includes:

[0016] A fixing bracket for fixing the intake detection element, and the fixing bracket is arranged on the rocker arm shaft seat or the cylinder block of the engine.

[0017] An in-cylinder intake negative pressure measuring device for an engine according to the present invention, wherein the intake detection element is a proximity switch or a travel switch or a contact switch.

[0018] An in-cylinder intake negative pressure measuring device for an engine according to the present invention, wherein the inlet of the valve communicates with the second end of the connection channel through a first joint, and the pressure detection element communicates with the outlet of the valve through a second joint.

[0019] An in-cylinder intake negative pressure measuring device for an engine according to the present invention, wherein the pressure detection element is a negative pressure sensor.

[0020] The present invention also provides an in-cylinder intake negative pressure measuring method for an engine, based on the in-cylinder intake negative pressure measuring device according to any one of the above, including:

[0021] The intake detection element detects the opening and closing of the valve of the cylinder block of the engine;

[0022] When the intake detection element detects that the valve of the cylinder block is open, the controller controls the valve to open, so that the pressure detection element communicates with the cylinder block; and the pressure detection element detects the pressure of the cylinder block during intake and transmits the detection signal to the data acquisition system;

[0023] When the intake detection element detects that the valve of the cylinder block is closed, the controller controls the valve to remain in the closed state.

[0024] A method for measuring the intake negative pressure in the engine cylinder provided by the present invention, wherein the intake detection element detects the opening and closing of the valve of the engine cylinder block, and includes:

[0025] When the intake detection element detects that the intake rocker arm of the engine is in the second position, the controller controls the valve to open;

[0026] When the intake detection element detects that the intake rocker arm of the engine is in the first position, the controller controls the valve to close.

[0027] The engine cylinder intake negative pressure measuring device and method provided by the present invention, the engine cylinder intake negative pressure measuring device includes a valve, a pressure detection element, a data acquisition system, an intake detection element and a controller. The inlet of the valve is communicated with the cylinder block of the engine, the pressure detection element is communicated with the outlet of the valve, and the data acquisition system is communicatively connected with the pressure detection element; the intake detection element is used to detect the opening and closing of the valve of the cylinder block, and the controller is communicatively connected with the valve and the intake detection element respectively, and the controller can control the opening and closing of the valve according to the detection signal of the intake detection element to connect or cut off the pressure detection element and the cylinder block of the engine.

[0028] When the intake detection element detects that the valve of the cylinder block is in the open state, after the controller receives the signal that the valve is in the open state transmitted by the intake detection element, the controller controls the valve to open, so that the cylinder block and the pressure detection element are connected. At this time, the pressure detection element can detect the pressure in the cylinder block, thereby realizing the detection of the negative pressure in the cylinder block during intake.

[0029] When the intake detection element detects that the valve of the cylinder block is in the closed state, the controller controls the valve to remain in the closed state to separate the cylinder block and the pressure detection element, so that the pressure detection element will not be affected by the high pressure and high temperature in the cylinder block, thereby ensuring the service life of the pressure detection element.

[0030] With such a setting, the negative pressure in the engine cylinder can be directly measured by the engine cylinder intake negative pressure measuring device, without indirect measurement or simulation calculation after indirect measurement, and its measurement result only contains the data of the engine intake stroke, which is convenient for analyzing the measurement result to facilitate the analysis of the influence of the negative pressure in the cylinder on the oil consumption of the engine; and the measuring device can use an ordinary negative pressure sensor with a small range and high precision to measure the negative pressure in the engine cylinder during intake. On the one hand, the measurement accuracy of the intake negative pressure in the engine cylinder can be improved, and on the other hand, there is no need to customize a special sensor, which is beneficial to reducing the measurement cost; the measurement is simple and fast, and the intake negative pressure of different schemes can be quickly measured to evaluate whether different TVA valve calibration schemes meet the requirements. Description of the Drawings

[0031] To more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0032] Figure 1 It is a schematic structural diagram of an in-cylinder intake negative pressure measuring device provided by the present invention;

[0033] Figure 2 It is a connection relationship diagram of a pressure detection element, a valve, and a connection channel provided by the present invention;

[0034] Figure 3 It is one of the position relationship diagrams between an intake detection element and a roller of an intake rocker arm provided by the present invention;

[0035] Figure 4 It is another position relationship diagram between an intake detection element and a roller of an intake rocker arm provided by the present invention.

[0036] Reference numerals:

[0037] 1. Cylinder head; 2. Valve; 3. Connection channel;

[0038] 4. Valve; 5. Pressure detection element; 6. Intake detection element;

[0039] 7. Controller; 8. Intake detection wiring harness; 9. Valve control wiring harness;

[0040] 10. Data acquisition system; 11. Display terminal; 12. Pressure detection wiring harness;

[0041] 13. Data transmission wiring harness; 14. Fixed bracket; 15. Intake rocker arm;

[0042] 16. Camshaft; 17. Intake cam; 18. Roller;

[0043] 19. Locking nut; 20. First joint; 21. Second joint. Detailed implementation manners

[0044] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will clearly and completely describe the technical solutions in the present invention in conjunction with the drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments in the present invention belong to the scope protected by the present invention.

[0045] The following will be described in conjunction with Figures 1 to 4Describe an in-cylinder intake negative pressure measurement device and method of the present invention.

[0046] As Figure 1 shown, an in-cylinder intake negative pressure measurement device provided by the present invention may include a valve 4, a pressure detection element 5, a data acquisition system 10, an intake detection element 6, and a controller 7.

[0047] Among them, the inlet of the valve 4 may be communicated with the cylinder block of the engine, and the pressure detection element 5 may be communicated with the outlet of the valve 4. In this way, when the valve 4 is opened, the pressure detection element 5 can be communicated with the cylinder block so that the pressure detection element 5 can measure the pressure in the cylinder block; when the valve 4 is closed, the pressure detection element 5 and the cylinder block can be disconnected, and the pressure detection element 5 can be prevented from being affected by the high temperature and high pressure in the cylinder block.

[0048] Here, the valve 4 may be a solenoid valve to facilitate automatic control.

[0049] The data acquisition system 10 may be communicatively connected to the pressure detection element 5. In this way, the pressure detection element 5 can transmit the detected pressure signal to the data acquisition system 10 for the data acquisition system 10 to collect the pressure signal for the operator to view. Here, the data acquisition system 10 is not specifically limited as long as it can realize data acquisition and storage.

[0050] In addition, the intake detection element 6 may be used to detect the opening and closing of the valve 2 of the cylinder block. The controller 7 may be communicatively connected to the valve 4 and the intake detection element 6 respectively, and the controller 7 may control the opening and closing of the valve 4 according to the detection signal of the intake detection element 6 to connect or cut off the pressure detection element 5 and the cylinder block. In this way, the pressure detection element 5 can measure the pressure in the cylinder block during intake, and the pressure detection element 5 and the cylinder block can be separated after intake is completed, so that the pressure detection element 5 will not be affected by the high pressure and high temperature in the cylinder block, thereby ensuring the service life of the pressure detection element 5.

[0051] Here, the controller 7 may be a PLC controller or other control devices or apparatuses.

[0052] Specifically, when the intake detection element 6 detects that the valve 2 of the cylinder block is in the open state, after the controller 7 receives the signal that the valve 2 is in the open state transmitted from the intake detection element 6, the controller 7 controls the valve 4 to open so that the inlet and outlet of the valve 4 are communicated, thereby connecting the cylinder block and the pressure detection element 5. At this time, the pressure detection element 5 can detect the pressure in the cylinder block, thereby realizing the detection of the negative pressure in the cylinder block during intake.

[0053] When the intake air detection element 6 detects that the valve 2 of the cylinder block is in the closed state, the controller 7 controls the valve 4 to remain in the closed state to separate the cylinder block from the pressure detection element 5, so that the pressure detection element 5 is not affected by the high pressure and high temperature in the cylinder block, thereby ensuring the service life of the pressure detection element 5.

[0054] With such a setting, the negative pressure in the engine cylinder can be directly measured by the engine in-cylinder intake negative pressure measuring device, without indirect measurement or simulation calculation after indirect measurement, and its measurement result only includes the data of the engine intake stroke, which is convenient for analyzing the measurement result to facilitate the analysis of the influence of the in-cylinder negative pressure on the engine oil consumption; and the measuring device can use an ordinary negative pressure sensor with a small range and high precision to measure the negative pressure in the engine cylinder during intake. On the one hand, it can improve the measurement accuracy of the in-cylinder intake negative pressure of the engine, and on the other hand, it does not require a customized special sensor, which is beneficial to reducing the measurement cost; the measurement is simple and fast, and can quickly measure the intake negative pressure of different schemes to evaluate whether different TVA valve calibration schemes meet the requirements.

[0055] In an alternative embodiment of the present invention, the engine in-cylinder intake negative pressure measuring device may further include a connecting channel 3. The connecting channel 3 can be arranged on the cylinder head 1 of the cylinder block, and the first end of the connecting channel 3 can communicate with the cylinder block, and the second end of the connecting channel 3 can communicate with the inlet of the valve 4. In this way, the valve 4 and the cylinder block can be connected through the connecting channel 3, so as to facilitate the pressure detection element 5 to detect the pressure in the cylinder block.

[0056] In an alternative embodiment, the inlet of the valve 4 and the second end of the connecting channel 3 can be connected through a first joint 20, and the outlet of the valve 4 and the pressure detection element 5 can be connected through a second joint 21. In this way, it is convenient to realize the connection of the connecting channel 3, the valve 4 and the pressure detection element 5.

[0057] In an alternative embodiment, the second end of the connecting channel 3 can be provided with a first internal thread, and the first end of the first joint 20 can be provided with a first external thread that matches the first internal thread, so that the connecting channel 3 and the first end of the first joint 20 can be threadedly connected; the second end of the first joint 20 can be provided with a second internal thread, and the inlet of the valve 4 can be provided with a second external thread that matches the second internal thread, so that the inlet of the valve 4 and the second end of the first joint 20 can be threadedly connected; the outlet of the valve 4 can be provided with a third internal thread, and the first end of the second joint 21 can be provided with a third external thread that matches the third internal thread, so that the outlet of the valve 4 and the second joint 21 can be threadedly connected; the second end of the second joint 21 can be provided with a fourth external thread, and the inlet of the pressure detection element 5 can be provided with a fourth internal thread that matches the fourth external thread, so that the second joint 21 and the pressure detection element 5 can be threadedly connected.

[0058] In an alternative embodiment, the pressure detection element 5 can be a negative pressure sensor. Specifically, the negative pressure sensor can be an ordinary high-frequency negative pressure sensor, which can directly output the negative pressure measurement result. Moreover, the negative pressure sensor can be a small-range negative pressure sensor. For example, the range of the negative pressure sensor here can be 10 - 20 bar to improve the measurement accuracy.

[0059] In an alternative embodiment of the present invention, the intake detection element 6 can be used to detect the position of the intake rocker arm 15 of the engine, so as to detect the opening and closing state of the valve 2 by detecting the position of the intake rocker arm 15.

[0060] Wherein, when the intake rocker arm 15 is in the first position, the valve 2 is in the closed state. That is, when the intake detection element 6 detects that the intake rocker arm 15 is in the first position, it is detected that the valve 2 is in the closed state. At this time, the controller 7 controls the valve 4 to be in the closed state.

[0061] When the intake rocker arm 15 is in the second position, the valve 2 is in the open state. That is, when the intake detection element 6 detects that the intake rocker arm 15 is in the second position, it is detected that the valve 2 is in the open state. At this time, the controller 7 controls the valve 4 to open, so that the pressure detection element 5 is communicated with the cylinder block, thereby enabling the pressure detection element 5 to detect the pressure in the cylinder.

[0062] In an alternative embodiment, the intake detection element 6 can be arranged above the roller 18 of the intake rocker arm 15. And when the intake rocker arm 15 is in the second position, the intake detection element 6 is triggered, so as to be able to transmit the detection signal to the controller 7, causing the controller 7 to control the valve 4 to open, so as to communicate the pressure detection element 5 with the cylinder block, thereby enabling the pressure detection element 5 to detect the pressure in the cylinder.

[0063] Here, the intake detection element 6 can detect the position of the roller 18 of the intake rocker arm 15 to detect the position of the intake rocker arm 15, thereby realizing the detection of the opening and closing state of the valve 2.

[0064] It should be noted that the engine includes a valve mechanism. The valve mechanism may include a valve 2 and a valve train. The valve 2 is disposed at the intake port of the cylinder block. The valve train includes a camshaft 16, a rocker shaft, an intake rocker 15, and a rocker shaft seat. The rocker shaft seat is disposed on the cylinder block. The middle of the intake rocker 15 is connected to the rocker shaft seat through the rocker shaft. The first end of the intake rocker 15 is connected to the valve 2, and a roller 18 is disposed at the second end of the intake rocker 15. And an intake cam 17 is provided on the camshaft 16. The operation of the engine can drive the camshaft 16 to rotate. The intake cam 17 on the camshaft 16 can push the roller 18 upward to rotate the intake rocker 15, move the second end of the intake rocker 15 upward, and move the first end of the intake rocker 15 downward to drive the valve 2 downward, so as to open the intake port of the combustion chamber and enable intake air.

[0065] In an alternative embodiment, the in-cylinder intake negative pressure measuring device of the engine may further include a fixing bracket 14. The fixing bracket 14 can be used to fix the intake detection element 6, and the fixing bracket 14 can be disposed on the rocker shaft seat or the cylinder block of the engine, so that the intake detection element 6 can be fixed above the roller 18 of the intake rocker 15 to facilitate the intake detection element 6 to detect the position of the intake rocker 15.

[0066] Here, the fixing bracket 14 can be fixedly connected to the rocker shaft seat or the cylinder block of the engine through fixing bolts.

[0067] In this embodiment, the fixing bracket 14 can be disposed on the rocker shaft seat of the engine, and the bottom end of the fixing bracket 14 can be fixedly connected to the rocker shaft seat. The intake detection element 6 can be fixedly disposed at the top end of the fixing bracket 14.

[0068] Alternatively, the fixing bracket 14 can be disposed on the cylinder block. Specifically, the fixing bracket 14 can be disposed on the cylinder head 1 of the cylinder block. The bottom end of the fixing bracket 14 can be fixedly connected to the cylinder head 1 of the cylinder block. The intake detection element 6 can be fixedly disposed at the top end of the fixing bracket 14.

[0069] Here, the top end of the fixing bracket 14 can be located above the roller 18 of the intake rocker 15.

[0070] In an alternative embodiment, the fixing bracket 14 can include a vertical rod and a horizontal rod. The horizontal rod can be connected to the top end of the vertical rod, and the horizontal rod can be located above the roller 18 of the intake rocker 15. The intake detection element 6 can be disposed on the horizontal rod. The vertical rod can be fixedly connected to the rocker shaft seat or the cylinder block of the engine to realize the fixation of the intake detection element 6.

[0071] In an alternative embodiment, the intake air detection element 6 may be a proximity switch, which is arranged above the roller 18 of the intake rocker arm 15. When the intake rocker arm 15 rotates to drive the valve 2 to open, the roller 18 of the intake rocker arm 15 moves upward. When the proximity switch detects the roller 18 (i.e., when the roller 18 moves into the detection range of the proximity switch), it indicates that the intake rocker arm 15 has opened the valve 2. At this time, it is the intake state, and the proximity switch transmits the signal of detecting the opening of the valve 2 to the controller 7. The controller 7 controls the opening of the valve 4 according to the received signal, so that the pressure detection element 5 is communicated with the cylinder block, thereby realizing the negative pressure detection of the cylinder block during intake.

[0072] In an alternative embodiment, the intake air detection element 6 may be a contact switch or a travel switch, which may be arranged above the roller 18 of the intake rocker arm 15. When the intake rocker arm 15 rotates to drive the valve 2 to open, the roller 18 of the intake rocker arm 15 moves upward. When the roller 18 of the intake rocker arm 15 touches the contact switch or the travel switch, the contact switch or the travel switch is triggered, which indicates that the intake rocker arm 15 has opened the valve 2. At this time, it is the intake state, and the contact switch or the travel switch transmits the trigger signal (i.e., the valve 2 opening signal) to the controller 7. The controller 7 controls the opening of the valve 4 according to the received signal, so that the pressure detection element 5 is communicated with the cylinder block, thereby realizing the negative pressure detection of the cylinder block during intake.

[0073] In an alternative embodiment, the intake air detection element 6 can be fixed to the fixed bracket 14 by two locking nuts 19. Specifically, a through hole for the intake air detection element 6 to pass through is provided on the cross bar, and the two locking nuts 19 are respectively sleeved on the intake air detection element 6. The two locking nuts 19 are respectively located on the upper and lower sides of the cross bar. Here, the outer diameters of the two locking nuts 19 are larger than the aperture of the through hole. In this way, the intake air detection element 6 can be fixed to the fixed bracket 14.

[0074] In an alternative embodiment of the present invention, the engine cylinder internal intake negative pressure measuring device further includes an intake air detection wire harness 8. The two ends of the intake air detection wire harness 8 are respectively connected to the intake air detection element 6 and the controller 7 to enable signal transmission between the intake air detection element 6 and the controller 7.

[0075] The engine cylinder internal intake negative pressure measuring device further includes a valve control wire harness 9. The two ends of the valve control wire harness 9 are respectively connected to the valve 4 and the controller 7 to enable signal transmission between the controller 7 and the valve 4, thereby realizing the control of the voltage on / off of the valve 4 by the controller 7.

[0076] The intake negative pressure measurement device for the engine cylinder further includes a pressure detection wire harness 12. The two ends of the pressure detection wire harness 12 are respectively connected to the pressure detection element 5 and the data acquisition system 10, so as to enable signal transmission between the pressure detection element 5 and the data acquisition system 10, thereby realizing the acquisition of the detection information of the pressure detection element 5.

[0077] In an alternative embodiment, the intake negative pressure measurement device for the engine cylinder may further include a display terminal 11 and a data transmission wire harness 13. The two ends of the data transmission wire harness 13 are respectively connected to the data acquisition system 10 and the display terminal 11, so as to transmit the data collected by the data acquisition system 10 to the display terminal 11 for the display terminal 11 to display, which is convenient for the operator to view.

[0078] Here, the display terminal 11 may be a computer, a mobile phone, a display, or other display devices.

[0079] Next, the intake negative pressure measurement method provided by the present invention will be described. The intake negative pressure measurement method for the engine cylinder described below can be correspondingly referred to the intake negative pressure measurement device for the engine cylinder described above.

[0080] An intake negative pressure measurement method provided by the present invention, based on the intake negative pressure measurement device for the engine cylinder described in any one of the above embodiments, may include:

[0081] The intake detection element 6 detects the opening and closing of the valve 2 of the cylinder block of the engine.

[0082] When the intake detection element 6 detects that the valve 2 of the cylinder block is opened, the controller 7 controls the valve 4 to open, so that the pressure detection element 5 is communicated with the cylinder block; and the pressure detection element 5 detects the pressure of the cylinder block during intake and transmits the detection signal to the data acquisition system 10.

[0083] When the intake detection element 6 detects that the valve 2 of the cylinder block is closed, the controller 7 controls the valve 4 to remain in the closed state.

[0084] In this way, when the valve 4 is opened, the pressure detection element 5 can be communicated with the cylinder block, so that the pressure detection element 5 can measure the pressure in the cylinder block; when the valve 4 is closed, the pressure detection element 5 and the cylinder block can be disconnected, which can prevent the pressure detection element 5 from being affected by the high temperature and high pressure in the cylinder block.

[0085] With such a setting, the negative pressure in the engine cylinder can be directly measured by the in-cylinder intake negative pressure measuring device of the engine, without the need for indirect measurement or simulation calculation after indirect measurement. Moreover, its measurement result only contains the data of the engine intake stroke, which is convenient for analyzing the measurement result and is conducive to analyzing the influence of the in-cylinder intake negative pressure on the engine oil consumption. And the measuring device can use an ordinary negative pressure sensor with a small range and high precision to measure the negative pressure in the engine cylinder during intake. On the one hand, it can improve the measurement accuracy of the in-cylinder intake negative pressure of the engine. On the other hand, there is no need to customize a special sensor, which is conducive to reducing the measurement cost. The measurement is simple and fast, and the intake negative pressure of different schemes can be quickly measured to evaluate whether different TVA valve calibration schemes meet the requirements.

[0086] In an alternative embodiment of the present invention, the intake detection element 6 detects the opening and closing of the valve 2 of the engine cylinder block, and may include:

[0087] When the intake detection element 6 detects that the intake rocker arm 15 of the engine is in the second position, the controller 7 controls the valve 4 to open;

[0088] When the intake detection element 6 detects that the intake rocker arm 15 of the engine is in the first position, the controller 7 controls the valve 4 to close.

[0089] When the engine working stroke ends, the engine enters the exhaust stroke stage. At this time, the high-temperature and high-pressure gas in the engine cylinder is released, and the temperature and pressure of the valve 2 rapidly decrease. As the engine further rotates, it drives the camshaft 16 to rotate. The intake cam 17 on the camshaft 16 pushes the roller 18 of the intake rocker arm 15 upward, so that the intake rocker arm 15 starts to move, and the valve 2 is pushed open. At this time, the distance between the roller 18 of the intake rocker arm 15 and the proximity switch decreases. The proximity switch detects the roller 18 and transmits the detection signal to the controller 7. After the judgment of the controller 7, it is determined that the valve 2 has been opened, so the solenoid valve is controlled to be energized and opened, connecting the connection channel 3 and the negative pressure sensor. The negative pressure sensor starts to measure the intake negative pressure in the engine cylinder and transmits the measurement signal to the data acquisition system 10, and then transmits it to the computer for recording.

[0090] When the engine intake stroke ends, the measurement of the intake negative pressure in the cylinder also ends. The engine then enters the compression and working strokes, and high-temperature and high-pressure gas is generated again inside the engine, posing a threat to the negative pressure sensor. After the engine intake stroke ends, the valve 2 closes, and the intake rocker arm 15 and the roller 18 return to the initial position, and the distance from the proximity switch becomes larger. The proximity switch can no longer detect the roller 18 and transmit the detection signal to the controller 7. After the judgment of the controller 7, the power supply to the solenoid valve is turned off, so that the solenoid valve closes, thereby cutting off the connection between the connection channel 3 and the negative pressure sensor, protecting the negative pressure sensor from the high-temperature and high-pressure gas in the cylinder under subsequent working conditions.

[0091] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An in-cylinder intake negative pressure measuring device for an engine, characterized in that, Comprising: A valve, the inlet of which is communicated with the cylinder block of the engine; A pressure detection element, which is communicated with the outlet of the valve; A data acquisition system, which is communicatively connected with the pressure detection element; An intake detection element, which is used to detect the opening and closing of the valve of the cylinder block; the intake detection element is used to detect the position of the intake rocker arm of the engine, wherein when the intake rocker arm is in the first position, the valve is in the closed state; when the intake rocker arm is in the second position, the valve is in the open state; The intake detection element is arranged above the roller of the intake rocker arm, and when the intake rocker arm is in the second position, the intake detection element is triggered; A controller, which is communicatively connected with the valve and the intake detection element, and the controller controls the opening and closing of the valve according to the detection signal of the intake detection element; A connection passage, which is arranged on the cylinder head of the cylinder block, the first end of the connection passage is communicated with the combustion chamber of the cylinder block, and the second end of the connection passage is communicated with the inlet of the valve; The inlet of the valve is communicated with the second end of the connection passage through a first joint, and the pressure detection element is communicated with the outlet of the valve through a second joint.

2. The in-cylinder intake negative pressure measuring device for an engine according to claim 1, characterized in that, Further comprising: A fixing bracket, which is used to fix the intake detection element, and the fixing bracket is arranged on the rocker arm shaft seat or the cylinder block of the engine.

3. The in-cylinder intake negative pressure measuring device for an engine according to claim 1, wherein The intake detection element is a proximity switch or a travel switch or a contact switch.

4. The in-cylinder intake negative pressure measuring device for an engine according to claim 1, characterized in that The pressure detection element is a negative pressure sensor.

5. A method for measuring the intake negative pressure in an engine cylinder, characterized in that, The engine in-cylinder intake negative pressure measuring device according to any one of claims 1-4, comprising: When the intake detection element detects that the intake rocker arm of the engine is in the second position, the valve is in the open state; When the intake detection element detects that the intake rocker arm of the engine is in the first position, the valve is in the closed state; When the intake detection element detects that the valve of the cylinder block is open, the controller controls the valve to open, so that the pressure detection element is communicated with the cylinder block of the engine; and the pressure detection element detects the pressure of the cylinder block during intake and transmits the detection signal to the data acquisition system; When the intake detection element detects that the valve of the cylinder block is closed, the controller controls the valve to remain in the closed state.

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