CN103486929B - A kind of device and method of accurate centering internal combustion engine top dead centre - Google Patents

Abstract

The invention belongs to the technical field of internal combustion engine debugging and detection, and relates to a device and method for accurately aligning the top dead center of an internal combustion engine. The device includes a sliding sleeve (2), a fixed seat (10), a probe (5) and a dial indicator (1); the sliding sleeve (2) is located in the sleeve-shaped fixed seat (10) and is fitted with a clearance to fix the The upper part of the seat (10) has a circular hole and a magnet (3) for absorbing the sliding sleeve (2) is embedded in the circular hole, and the lower part of the inner hole of the fixed seat has an annular clamping table (9), and the probe (5) It is located in the inner hole of the fixed seat (10) and the sliding sleeve (2), and the middle section is located in the inner hole between the lower end surface of the sliding sleeve and the ring-shaped platform at the lower part of the fixed seat. The diameter of the middle section of the probe (5) is larger than The diameter of the outer circle of the sliding sleeve is greater than the inner diameter of the ring clamp (9) at the lower part of the fixing seat, and the lower part of the probe (5) protrudes from the fixing seat (10); the probe of the dial indicator is inserted into the upper part of the sliding sleeve hole and fasten to the unit with screws.

Description

A device and method for accurately aligning the top dead center of an internal combustion engine

technical field

The invention belongs to the technical field of internal combustion engine debugging and detection, and relates to a device and method for accurately aligning the top dead center of an internal combustion engine.

Background technique

The fuel injection advance angle of the internal combustion engine plays an important role in the stable operation of the whole machine. If the fuel injection advance angle is not adjusted correctly or the accuracy is not high, the internal combustion engine will have abnormal phenomena such as poor combustion and insufficient power, which will affect the service life and economy of the internal combustion engine. , so it is necessary to calibrate the fuel injection advance angle during internal combustion assembly and maintenance. The fuel injection advance angle is calibrated in two steps. The first step: accurately find the top dead center (that is, find the top dead center of the piston of the standard cylinder); the second step: take the found top dead center as the zero position, The reading of the sub-meter and the scale of the flywheel are used to determine the size of the fuel injection advance angle; it can be seen that the accuracy of the top dead center alignment will directly affect the accuracy of the calibration of the fuel injection advance angle.

At present, the method of finding the top dead center of the internal combustion engine is completed through the cooperation of a probe rod and a dial indicator, that is, first contact the bottom of the probe rod with the top of the piston, and then use the dial indicator to touch the top of the probe rod to measure the stroke of the probe rod , after repeated cranking, find the middle value of the dial indicator reading, and finally determine the top dead center. This alignment method takes a long time to operate, requires a high skill level of the operator, and has low alignment accuracy.

Contents of the invention

The purpose of the present invention is to propose a device and method for accurately aligning the top dead center of an internal combustion engine, so that it can accurately align the top dead center, reduce operational errors, ensure the accuracy of the fuel injection advance angle, and meet the requirements for good operation of the internal combustion engine .

The present invention completes its inventive task through the following technical solutions:

A device for accurately aligning the top dead center of an internal combustion engine, the device includes a sliding sleeve, a fixed seat, a probe and a dial indicator; the sliding sleeve is sleeve-shaped, and the dial indicator is arranged on the sliding sleeve In the upper part, the inner hole of the sliding sleeve is a stepped hole, the upper small-diameter inner hole is used to install the probe of the dial indicator, and the lower large-diameter inner hole is the space for the probe to run. The middle part of the sliding sleeve is provided with a waist-shaped The hole observation window I is used to observe the running position of the probe from time to time; the fixed seat is in the shape of a sleeve, the sliding sleeve is located in the fixed seat and has a clearance fit with the fixed seat, and the sliding sleeve The length is less than the length of the fixed seat, and the upper part of the fixed seat has a round hole and a magnet is embedded in the round hole, which is used to absorb the sliding sleeve, so that the sliding sleeve will not slide due to its own gravity; the fixed seat has Waist-shaped hole observation window II, the observation window II on the fixed seat overlaps with the observation window I on the sliding sleeve, so as to observe the movement position of the probe rod from time to time; there is a shoulder on the outer circle of the middle part of the fixed seat, and the bottom of the shoulder The end face fits with the end face of the fuel injector hole of the internal combustion engine, and the outer circle of the lower part of the fixing seat fits with the outer circle of the fuel injector hole of the internal combustion engine. The two fitting structures enable the entire device to be installed in the fuel injector hole of the internal combustion engine; The lower part of the inner hole of the fixed seat has an annular clamping table to prevent the probe from being separated from the whole device; the lower part of the fixed seat is provided with a vent hole for discharging the compressed air in the cylinder of the internal combustion engine; the probe is located on the fixed seat, sliding In the inner hole of the sleeve, the probe is a long stepped shaft, the upper and lower end surfaces of the probe are flat and smooth measuring surfaces, and the middle section of the probe is located between the lower end surface of the sliding sleeve and the annular clamping platform at the lower part of the fixed seat. In the inner hole between them, the diameter of the middle section of the probe rod is larger than the diameter of the outer circle of the sliding sleeve, and larger than the inner diameter of the annular clamping platform at the lower part of the fixed seat, so as to ensure that the probe rod can lift up the sliding sleeve and move upward when it is working. And not separated from the whole device, the lower part of the probe protrudes from the fixed seat; the dial indicator is a standard part, and the probe of the dial indicator is inserted into the inner hole of the upper part of the sliding sleeve and fixed on it with screws. on the device.

Using the above-mentioned device to find the top dead center of the internal combustion engine, first fit the lower end surface of the middle section of the probe to the ring clamping table below the inner hole of the fixing seat so that there is no gap, and install a dial indicator on the upper part of the sliding sleeve, because Due to the adsorption effect of the magnet, the sliding sleeve will not fall; then the device is placed in the fuel injector hole of the internal combustion engine, so that the lower end surface of the shoulder of the fixing seat fits with the end surface of the fuel injector hole of the internal combustion engine, and the outer surface of the lower part of the fixing seat The circle fits the outer circle of the fuel injector hole of the internal combustion engine, and then the crankshaft is turned, and the top of the piston pushes the probe to move upward. When the upper end surface of the middle section of the probe just bears against the sliding sleeve, the dial gauge is preloaded for a certain distance And zero, lock the dial indicator with the set screw, continue to rotate the crankshaft, the probe overcomes the adsorption force of the magnet, and pushes the sliding sleeve upward. During this process, the pointer of the dial indicator remains unchanged. , continue to turn the crankshaft, the piston will move down, the probe will also move down, the sliding sleeve will remain stationary under the adsorption of the magnet, and the reading of the dial indicator will become smaller, and then turn the crankshaft in the opposite direction to make the piston withstand The sliding sleeve goes up, and when the reading of the dial indicator is the preload value, this point is the precise top dead center of the standard cylinder.

The device and method for accurately aligning the top dead center of the internal combustion engine proposed by the present invention can realize precise alignment of the position of the top dead center of the internal combustion engine piston; the device is easy to use, can effectively save operating time, and reduce the impact on the operator's skill level Require.

Description of drawings

Fig. 1 is the structural representation of device of the present invention;

In the figure: 1. Dial indicator; 2. Sliding sleeve; 3. Magnet; 4. Air vent; 5. Probe; 6. Set screw; 7. Observation window II; ; 10, fixed seat.

detailed description

The present invention is further described in conjunction with accompanying drawing and embodiment:

As shown in Figure 1, a device for accurately aligning the top dead center of an internal combustion engine, the device includes a sliding sleeve 2, a fixed seat 10, a probe 5 and a dial indicator 1; the sliding sleeve 2 is sleeve-shaped, and the The dial indicator 1 is arranged on the upper part of the sliding sleeve 2, the inner hole of the sliding sleeve 2 is a stepped hole, the upper small-diameter inner hole is used to install the probe of the dial indicator, and the lower large-diameter inner hole is a probe. Rod running space, the middle part of the sliding sleeve 2 is provided with an observation window I with a waist-shaped hole, which is used to observe the running position of the probe rod from time to time; the fixing seat 10 is sleeve-shaped, and the sliding sleeve 2 is located on the In the fixed seat 10 and with the fixed seat 10 for clearance fit, the length of the sliding sleeve 2 is less than the length of the fixed seat 10, the upper part of the fixed seat 10 has a round hole and a magnet 3 is embedded in the round hole , used to absorb the sliding sleeve 2, so that the sliding sleeve will not slide down due to its own gravity; the fixed seat 10 is provided with an observation window II7 with a waist-shaped hole, and the observation window II7 on the fixed seat overlaps with the observation window I on the sliding sleeve , in order to observe the moving position of the probe rod from time to time; there is a shoulder on the outer circle of the middle part of the fixed seat, and the lower end surface of the shoulder fits with the end surface of the fuel injector hole of the internal combustion engine, and the outer circle at the lower part of the fixed seat is in contact with the fuel injector of the internal combustion engine. The outer circle of the hole fits together, and the structure of the two fits enables the whole device to be installed in the fuel injector hole of the internal combustion engine; the lower part of the inner hole of the fixing seat has an annular clamping table 9 to prevent the probe from being separated from the whole device; The seat is provided with a ventilation hole 4, which is used to discharge the compressed air in the cylinder of the internal combustion engine; the probe 5 is located in the inner hole of the fixed seat 10 and the sliding sleeve 2, and the probe 5 is a long stepped shaft. The upper and lower end surfaces of the rod 5 are flat and smooth measuring surfaces, and the middle section of the probe rod 5 is located in the inner hole between the lower end surface of the sliding sleeve and the ring-shaped platform at the bottom of the fixed seat. The diameter of the middle section of the probe rod 5 is It is larger than the diameter of the outer circle of the sliding sleeve, and is larger than the inner diameter of the annular card table 9 at the bottom of the fixed seat, so as to ensure that the probe can lift the sliding sleeve and move upwards when the probe is working, and will not be separated from the entire device. The lower part of the probe 5 Stretch out described fixed seat 10; Described dial indicator 1 is a standard part, and the probe of described dial indicator is inserted into the inner hole of the upper part of the sliding sleeve, and fixed on the device with screws.

Using the above-mentioned device to find the top dead center of the internal combustion engine, first fit the lower end surface of the middle section of the probe 5 to the ring-shaped clamping table 9 below the inner hole of the fixing seat so that there is no gap, and install the percent on the upper part of the sliding sleeve 2 Table 1, due to the adsorption effect of the magnet 3, the sliding sleeve 2 remains stationary relative to the fixed seat; then the above-mentioned device is placed in the fuel injector hole of the internal combustion engine, so that the lower end surface of the shoulder of the fixed seat and the end surface of the fuel injector hole of the internal combustion engine Fitting, the outer circle of the lower part of the fixed seat fits the outer circle of the fuel injector hole of the internal combustion engine, and then the crankshaft is turned, and the top of the piston pushes the probe 5 to move upward, when the upper end surface of the middle section of the probe just bears against the sliding sleeve 2 , preload the dial indicator for a certain distance and adjust it to zero, lock the dial indicator with the set screw, continue to rotate the crankshaft, the probe overcomes the adsorption force of the magnet, and pushes the sliding sleeve 2 to rise. During this process, the dial indicator The pointer remains unchanged. When the crankshaft continues to rotate after reaching the top dead center, the piston will move downward, and the probe 5 will also move downward. The sliding sleeve 2 remains still under the adsorption of the magnet, and the reading of the dial indicator will change Small, then turn the crankshaft in the opposite direction to make the piston go up against the sliding sleeve 2. When the reading of the dial gauge 1 is the preload value, this point is the accurate top dead center of the standard cylinder.

Claims (2)

1. A device for accurately aligning the top dead center of an internal combustion engine, characterized in that: the device includes a sliding sleeve (2), a fixed seat (10), a probe (5) and a dial indicator (1); the sliding The sleeve (2) is in the shape of a sleeve, the dial indicator (1) is set on the upper part of the sliding sleeve (2), the inner hole of the sliding sleeve (2) is a stepped hole, and the upper small diameter inner hole is used For the probe installed with the dial indicator, the large-diameter inner hole at the lower part is the space for the probe rod to run, and the middle part of the sliding sleeve (2) is provided with an observation window I with a waist-shaped hole, which is used to observe the running position of the probe rod from time to time; The fixing seat (10) is in the shape of a sleeve, the sliding sleeve (2) is located in the fixing seat (10) and is in clearance fit with the fixing seat (10), the length of the sliding sleeve (2) Less than the length of the fixed seat (10), the upper part of the fixed seat (10) has a round hole and a magnet (3) is embedded in the round hole, which is used to absorb the sliding sleeve (2), so that the sliding sleeve (2) It will not slide down due to its own gravity; the fixed seat (10) is also provided with a waist-shaped hole observation window II (7), and the observation window II on the fixed seat overlaps with the observation window I on the sliding sleeve, so that it can be observed from time to time. The position of the rod movement; the outer circle of the middle part of the fixed seat is provided with a shoulder (8), the lower end surface of the shoulder is fitted with the end surface of the fuel injector hole of the internal combustion engine, and the outer circle of the lower part of the fixed seat is aligned with the outer surface of the fuel injector hole of the internal combustion engine. Round fit, two fit structures enable the whole device to be installed in the fuel injector hole of the internal combustion engine; the lower part of the inner hole of the fixing seat has an annular clamping platform (9) to prevent the probe (5) from being separated from the whole device The fixed seat is provided with a ventilation hole (4), which is used to discharge the compressed air in the cylinder of the internal combustion engine; the probe (5) is located in the inner hole of the fixed seat (10) and the sliding sleeve (2), and the The probe (5) is a long stepped shaft, the upper and lower end surfaces of the probe (5) are flat and smooth measuring surfaces, and the middle section of the probe (5) is located between the lower end surface of the sliding sleeve and the ring clip at the lower part of the fixing seat. In the inner hole between the platforms, the diameter of the middle section of the probe (5) is larger than the diameter of the outer circle of the sliding sleeve, and larger than the inner diameter of the annular clamping platform (9) at the lower part of the fixed seat, so as to ensure that the probe can work The jacking sliding sleeve moves upward without being separated from the whole device, and the lower part of the probe (5) protrudes from the fixed seat (10); the dial indicator (1) is a standard part, and the dial indicator (1) is a standard part. After the probe of the meter is inserted into the upper inner hole of the sliding sleeve, it is fixed on the device with screws. 2. The method for aligning the top dead center of the internal combustion engine with a device for accurately aligning the top dead center of the internal combustion engine according to claim 1 is characterized in that: firstly connect the lower end surface of the middle section of the probe (5) to the inner hole of the fixed seat The lower ring clamp (9) fits together so that there is no gap, and the dial indicator (1) is installed on the upper part of the sliding sleeve. Due to the adsorption effect of the magnet (3), the sliding sleeve (2) will not fall; then the Put the device into the fuel injector hole of the internal combustion engine, make the lower end surface of the shoulder of the fixing seat fit the end surface of the fuel injector hole of the internal combustion engine, and the outer circle of the lower part of the fixing seat fit the outer circle of the fuel injector hole of the internal combustion engine, and turn the crankshaft , the top of the piston pushes the probe (5) to move upwards. When the upper end surface of the middle section of the probe just bears against the sliding sleeve (2), preload the dial indicator (1) for a certain distance and set the preload value to Baseline value, lock the dial indicator with the set screw (6), continue to rotate the crankshaft, the probe overcomes the adsorption force of the magnet (3), and pushes the sliding sleeve (2) upward, during this process, the pointer of the dial indicator does not move After reaching the top dead center, continue to turn the crankshaft, the piston will move down, the probe (5) will also move down, the sliding sleeve (2) remains stationary under the adsorption of the magnet (3), and the percentage The reading of the gauge will become smaller, and then reversely turn the crankshaft to make the piston go up against the probe, thereby pushing the sliding sleeve up. When the reading of the dial gauge is the preload value, this point is the precise top dead center of the standard cylinder.