CN105973188A - System and method for measurement of engine jet pipe axis - Google Patents

Abstract

The invention relates to a measuring system and method for the axis of an engine nozzle. The measurement system of the nozzle axis of the engine includes: a leveling mount and a rotating measuring device; the rotating measuring device includes a measuring rod, and the measuring rod rotates in the circumferential direction; the measuring rod is provided with an angle sensor and a plurality of laser displacements sensor; the plurality of laser displacement sensors are located at different heights of the measuring rod for measuring the radial distance between the inner wall of the nozzle and the corresponding laser displacement sensor; the angle sensor is located on the measuring rod for measuring The rotation angle of the measuring rod; the measuring rod is vertically arranged on the leveling mount; the leveling mount is in contact with the nozzle of the engine nozzle. The invention realizes non-contact measurement of the axis of the nozzle of the engine, avoids damage to the inner wall of the nozzle caused by contact measurement, and has accurate measurement results.

Description

Measuring System and Method of Engine Nozzle Axis

technical field

The invention relates to the field of mechanical measurement, in particular to a measurement system and method for the axis of an engine nozzle.

Background technique

The axis of the nozzle of the engine is the thrust line of the engine, which is the line of action of the synthetic thrust of the engine. The axis of the nozzle in the power system, especially the axis of the nozzle of the rocket engine, needs to be accurately designed. The axis of the nozzle of the existing rocket engine is only determined by design, and the premise is that the machining error is small and the deformation of the nozzle after forming is small. The deviation between the real axis and the design needs to be found by measurement. However, using conventional measurement methods, it is difficult to measure the axis of the engine nozzle by contact with measuring tools.

The axis is inside the nozzle and is determined by the shape of the inside of the nozzle. There are generally protrusions outside the nozzle, so the axis measurement needs to be carried out inside the nozzle. The axis of the nozzle cannot be measured directly. It is necessary to measure the truncation circles on the inner wall, calculate the center of the truncation circles, and connect the centers of the truncation circles to obtain the nozzle axis. Measure each cut circle on the inner wall of the nozzle. The inner cut circle may be an ellipse, and more measurement points are needed to accurately obtain the center position of the circle. However, it is not easy to ensure measurement on the same internal truncated circle in conventional measurement. Since the nozzle is similar to a cone, measurement at different truncated circles will bring large errors, and the error caused by the measurement itself is greater than the actual deviation of the axis. measurement becomes meaningless.

Engine nozzles, especially rocket engine nozzles, are expensive, and bumping is strictly prohibited. In routine measurements, measuring tools need to be used to touch the inner wall of the nozzle, which will inevitably bump or scratch the inner wall, causing losses.

Contents of the invention

The technical problem to be solved by the present invention is: the existing method for measuring the axis of the contact nozzle will cause damage to the inner wall of the nozzle and cause large measurement errors.

In order to solve the above-mentioned technical problem, the present invention proposes a kind of measurement system of engine nozzle axis on the one hand, the measurement system of this engine nozzle axis comprises:

Leveling mounts and rotating measuring devices;

The rotating measuring device comprises a measuring rod, and the measuring rod rotates in a circumferential direction;

An angle sensor and a plurality of laser displacement sensors are arranged on the measuring rod;

The plurality of laser displacement sensors are located at different heights of the measuring rod for measuring the radial distance between the inner wall of the nozzle and the corresponding laser displacement sensors;

The angle sensor is located on the measuring rod for measuring the rotation angle of the measuring rod;

The measuring rod is vertically arranged on the leveling mount;

The leveling mount is in contact with the nozzle of the engine nozzle.

Optionally, the measuring system of the engine nozzle axis also includes a signal recording and processor;

The signal recording and processor are connected with the angle sensor and a plurality of laser displacement sensors, and are used to acquire the axis of the nozzle.

Optionally, the leveling mount includes a first bearing and a second bearing;

The measuring rod includes a rotating shaft rod and a plurality of spreading rods;

The rotating shaft rod is vertically arranged on the leveling mount through the first bearing and the second bearing;

The multiple laser displacement sensors are respectively arranged on the multiple exhibition poles.

Optionally, the angle sensor is located at the bottom of the rotating shaft rod, and the rotating shaft of the angle sensor is connected to the shaft center of the rotating shaft rod.

Optionally, the shape of the leveling mount is triangular.

Optionally, the measuring rod is located on a predetermined central axis of the measuring system of the engine nozzle axis.

Optionally, the measuring system of the engine nozzle axis also includes:

Three upward adjustment boards and three guide rods;

The upward adjustment posture plate is arranged on the leveling seat frame, and is used for contacting with the spout of the engine nozzle, and adjusting the spout to be in a horizontal state;

The three guide rods are respectively vertically arranged on the positions where the three upward attitude adjustment plates are away from the measuring rod, so as to guide the placement of the engine nozzle.

Optionally, the measuring system of the engine nozzle axis also includes:

Three lower posture boards;

The three lower posture adjustment plates are arranged at the bottom of the leveling seat frame, and are used to adjust the leveling seat frame (1) to be in a horizontal state.

Another aspect of the present invention proposes a method for measuring the axis of an engine nozzle, the method comprising:

Obtain the radial distance between the inner wall of the nozzle and the corresponding laser displacement sensor;

Obtain the rotation angle of the measuring rod;

The centers of multiple truncated circles are obtained according to the radial distance between the inner wall of the nozzle and the corresponding laser displacement sensor and the rotation angle of the measuring rod, and the axis of the engine nozzle is obtained by connecting the centers of the truncated circles.

Optionally, the obtaining the centers of multiple truncated circles according to the radial distance between the inner wall of the nozzle and the corresponding laser displacement sensor and the rotation angle of the measuring rod includes:

A least square fitting method is used to fit the radial distance between the inner wall of the nozzle and the corresponding laser displacement sensor and the rotation angle of the measuring rod to obtain the centers of multiple truncated circles.

The measurement system and method of the engine nozzle axis proposed by the present invention realize the non-contact measurement of the engine nozzle axis, avoid the damage caused by the contact measurement to the inner wall of the nozzle, and obtain the engine nozzle inner wall through a plurality of laser displacement sensors. The radial distance of multiple truncated circles of the wall is used to obtain the rotation angle of the measuring rod through the angle sensor, and the axis of the nozzle is obtained according to the radial distance of the multiple truncated circles and the rotational angle of the measuring rod, and the measurement result is accurate.

Description of drawings

The features and advantages of the present invention will be more clearly understood by referring to the accompanying drawings, which are schematic and should not be construed as limiting the invention in any way. In the accompanying drawings:

Fig. 1 shows the structural representation of the measurement system of the engine nozzle axis of an embodiment of the present invention;

Fig. 2 shows the structural representation of engine nozzle;

Fig. 3 shows the structural representation of lowering posture board;

Figure 4 shows a schematic structural view of the leveling mount;

Figure 5 shows a schematic diagram of the docking installation of the lower attitude plate and the leveling seat;

Fig. 6 shows the structural representation of the upward adjustment posture board;

Fig. 7 shows the schematic diagram of installation of the guide bar, the upper posture adjustment plate and the leveling seat frame;

Figure 8 shows a schematic diagram of the bearing installation structure;

Fig. 9 shows the structural representation of measuring rod;

Fig. 10 shows the connection schematic diagram of measuring rod and bearing;

Fig. 11 shows the schematic diagram of the installation of the laser displacement sensor;

Figure 12 shows the schematic diagram of the installation of the angle sensor and the leveling mount;

Fig. 13 shows a schematic flow chart of a method for measuring the axis of an engine nozzle according to an embodiment of the present invention;

Fig. 14 shows the schematic diagram of the rotation angle-time measured by the angle sensor;

Fig. 15 shows a schematic diagram of the distance-time measured by the laser displacement sensor;

Fig. 16 shows the schematic diagram of the angle-distance relationship curve and the cut circle;

Figure 17 shows a schematic diagram of the four truncated circles and the axis of the nozzle.

In Figure 1-Figure 12:

1 leveling mount, 2 rotating measuring device;

11 the first bearing, 12 the second bearing, 13 the upward adjustment plate, 14 the downward adjustment plate, 15 the guide rod;

21 measuring rod, 22 angle sensor, 23 laser displacement sensor;

211 shaft rod, 212 exhibition rod;

141 the first upper nut, 142 the first lower nut;

131 second upper nut, 132 second lower nut;

211' threaded connection holes.

detailed description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Fig. 1 shows a schematic structural diagram of a measuring system for an engine nozzle axis according to an embodiment of the present invention. As shown in Figures 1-12, the measuring system of the nozzle axis of the engine includes:

Leveling mount 1 and rotating measuring device 2;

The rotating measuring device 2 comprises a measuring rod 21, and the measuring rod 21 rotates circumferentially;

The measuring rod 21 is provided with an angle sensor 22 and a plurality of laser displacement sensors 23;

A plurality of laser displacement sensors 23 are located at different heights of the measuring rod 21 for measuring the radial distance between the nozzle inner wall and the corresponding laser displacement sensors;

The angle sensor 22 is located on the measuring rod 21 for measuring the rotation angle of the measuring rod 21;

The measuring rod 21 is vertically arranged on the leveling seat frame 1;

The leveling mount 1 is in contact with the nozzle of the engine nozzle.

The measurement system of the engine nozzle axis in this embodiment realizes the non-contact measurement of the engine nozzle axis, avoids the damage caused by the contact measurement to the inner wall of the nozzle, and obtains the position of the inner wall of the engine nozzle through a plurality of laser displacement sensors. The radial distance of multiple truncated circles is used to obtain the rotation angle of the measuring rod through the angle sensor, and the axis of the nozzle is obtained according to the radial distance of multiple truncated circles and the rotational angle of the measuring rod, and the measurement result is accurate.

In an optional implementation, the engine nozzle axis measurement system also includes a signal recorder and processor (not shown in the figure);

The signal recording and processor are connected with an angle sensor 22 and a plurality of laser displacement sensors 23, and are used to obtain the nozzle according to the radial distance between the inner wall of the nozzle and the corresponding laser displacement sensor and the rotation angle of the measuring rod 21. axis of the tube.

In practical applications, two power supplies are used to supply power to the laser displacement sensor and the angle sensor respectively, and a signal recorder is used to record the laser displacement and angle signals.

Further, the leveling mount 1 includes a first bearing 11 and a second bearing 12;

The measuring rod 21 includes a rotating shaft rod 211 and a plurality of spreading rods 212;

The rotating shaft rod 211 is vertically arranged on the leveling seat frame 1 through the first bearing 11 and the second bearing 12;

A plurality of laser displacement sensors 23 are respectively disposed on a plurality of extension poles 212 .

Further, the angle sensor 22 is located at the bottom of the rotating shaft rod 211 , and the rotating shaft of the angle sensor 22 is connected to the axis of the rotating shaft rod 211 .

The measurement system of the engine nozzle axis in this embodiment solves the problem of continuous multi-point measurement of the same truncated circle inside the nozzle and the problem of non-contact measurement.

Preferably, the shape of the leveling mount 1 is a triangle. The measuring rod 21 is located on the predetermined central axis of the measuring system of the engine nozzle axis.

The measurement system of the nozzle axis of the engine also includes: three upward adjustment plates 13 and three guide rods 15;

The upward adjustment posture plate 13 is arranged on the leveling seat frame 1, and is used for contacting with the spout of the engine nozzle, and the spout is adjusted to be in a horizontal state;

Three guide rods 15 are respectively vertically arranged on the positions where the three upper posture adjustment plates 13 are away from the measuring rod 21, so as to guide the placement of the engine nozzle.

The measurement system of the nozzle axis of the engine also includes: three downward adjustment plates (14);

The three lower posture adjustment plates (14) are arranged at the bottom of the leveling seat frame (1), and are used for adjusting the leveling seat frame (1) to be in a horizontal state.

In practical application, the measuring rod is welded vertically by a rotating shaft rod and several spreading rods. The rotating shaft rod is placed on the leveling frame through the socket bearing, and the measuring rod can realize continuous rotation around the bearing. The displacement sensor is connected with the angle sensor at the lower end of the rotating shaft rod. The lower posture board is used to adjust the entire measurement system to be in a horizontal state. The upward adjustment posture plate is used to place the nozzle of the engine nozzle, and adjust the nozzle plane of the engine nozzle (as shown in Figure 2) to be in a horizontal state. The guide rod is used for guiding when the engine nozzle is docked with the upward attitude adjustment plate.

The screw rod of the lower attitude plate 14 (as shown in Figure 3 ) passes through the through hole of the leveling seat frame 1 base (as shown in Figure 4 ), and is clamped and fixed by the first upper nut 141 and the second lower nut 142 (as shown in Figure 5 ). ), adjust the upper end surface of the seat frame to be in a horizontal state by rotating the nut. The screw rod of the attitude-adjusting plate 13 (as shown in Figure 6) passes through the top seat through hole of the leveling seat frame 1, and is clamped and fixed by the first upper nut 131 and the second lower nut 132 (as shown in Figure 7). The guide rod 15 is screwed on the leveling seat frame 1, and is used to control the directionality of the spray pipe and the upper posture adjustment plate 13 in the process of docking.

A counterbore is processed in the middle of the leveling seat frame 1 for placing an upper and a lower bearing respectively, and a radial screw is used to ensure that the bearing is tightly matched with the leveling seat frame 1 (as shown in Figure 8 ). The rotating shaft rod 211 of measuring rod 21 (as shown in Figure 9) is passed through the inner diameters of the two bearings in series, and the rotating shaft rod 211 is slightly tightly fitted with the inner ring of the bearing, and the protrusion on the rotating shaft rod is pressed on the inner ring of the upper bearing (as shown in Figure 10 shown); the length of the extension rod 212 is preferably adjusted according to the size of the engine nozzle, because the nozzle is tapered, narrow at the top and wide at the bottom, therefore, the length of a plurality of extension rods shown in Figure 9 is from top to bottom increase in turn. For the measurement system of the nozzle axis, the overall horizontal state of the measurement system can be leveled by lowering the attitude plate, and the horizontal state of the tested object can be leveled by raising the attitude plate, and the rotation measurement can be realized by rotating the measuring rod around the bearing.

According to the number of truncated circles to be measured, the measuring distance of the laser displacement and the internal profile of the engine nozzle, the size of the measuring rod 21 is designed to ensure that the size of the measuring rod 21 is smaller than the internal profile of the nozzle, even if the height of the measuring rod 21 is less than that of the nozzle The height is such that the length of the spreading rod 211 on the measuring rod is generally less than the radius of the nozzle, so that the rotating bracket does not touch the inner wall of the nozzle during the measurement and meets the laser displacement measurement distance.

A laser displacement sensor 23 is installed on the extension rod 211 of the measuring rod 21 . The laser displacement sensor 23 is fixedly connected with the measuring rod 21 (as shown in Figure 11 ) by the threaded connection hole 211 ' processed on the spreading rod 211, and the laser displacement sensor 23 emits the distance between the laser measuring sensor and the inner wall of the nozzle. The shape of the measuring rod and the number of laser displacement sensors are adjusted according to the inner shape of the nozzle and the number of measuring truncation circles.

The angle sensor 22 housing is installed on the leveling seat frame 1, and the test shaft of the angle sensor 22 is connected to the axis of the shaft 211 of the measuring rod 21 (as shown in Figure 12 ), for measuring the angle of the measuring rod rotation.

In practical application, the process of placing and leveling the engine nozzle is as follows: use a crane to lift the nozzle, the nozzle of the engine faces downward, and the nozzle slowly falls. During the docking process, observe the distance between the edge of the nozzle and the three guide rods Consistent, the nozzle nozzle is finally close to the upward adjustment posture board, and the nozzle and the upward adjustment posture board do not move relative to each other.

By rotating the nut of the upward adjustment plate, the upward adjustment plate is raised and lowered, and the angle of the nozzle mouth is measured with a level ruler, so as to adjust the nozzle mouth to be in a horizontal state.

Connect the power supply to the sensor and connect the signal recorder to check the laser beam emitted by the laser displacement sensor. The recorder can normally receive the displacement signal of the laser displacement sensor and the angle signal of the angle sensor, and can carry out the measurement of the nozzle axis. During the measurement process, use the manual to rotate the rotating bracket slowly and roughly at a constant speed, and the measurement ends after one rotation. Check that all laser displacement data and rotation angle data have been measured.

According to the laser displacement measurement data and rotation angle measurement data, the least square method is used to fit the center of each truncated circle, and the nozzle axis is obtained by connecting the centers of each truncated circle.

Fig. 13 shows a schematic flowchart of a method for measuring the axis of an engine nozzle according to an embodiment of the present invention. As shown in Figure 13, the measuring method of the engine nozzle axis of this embodiment comprises:

S131: Obtain the radial distance between the inner wall of the nozzle and the corresponding laser displacement sensor;

S132: Obtain the rotation angle of the measuring rod;

S133: Obtain the centers of multiple truncated circles according to the radial distance between the inner wall of the nozzle and the corresponding laser displacement sensor and the rotation angle of the measuring rod, and connect the centers of the truncated circles to obtain the axis of the engine nozzle.

Further, the acquisition of the centers of multiple truncated circles according to the radial distance between the inner wall of the nozzle and the corresponding laser displacement sensor and the rotation angle of the measuring rod includes:

A least square fitting method is used to fit the radial distance between the inner wall of the nozzle and the corresponding laser displacement sensor and the rotation angle of the measuring rod to obtain the centers of multiple truncated circles.

The method for measuring the engine nozzle axis of the present invention will be introduced below in combination with a specific embodiment.

Step 1: Rotate Bracket Design

It is required to measure four truncated circles inside the nozzle, and take the line connecting the centers of the four truncated circles as the axis of the nozzle. The measuring distance of the selected laser displacement sensor is 80mm-300mm, and the rotating bracket is designed according to the internal shape of the nozzle, as shown in Figure 9. The extension rod of the measuring rod is about 130mm away from the inner wall of the nozzle, which meets the measurement distance of the laser displacement sensor and ensures that the rotating bracket and the laser displacement sensor will not touch the inner wall of the nozzle.

Step 2: Building the Rotating Measuring Device

The lowering attitude plate screw passes through the through hole of the base of the leveling frame, and is clamped and fixed by the upper and lower nuts, and the upper end surface of the frame is adjusted to be in a horizontal state through the rotation of the nuts. The screw rod of the upward adjustment posture plate passes through the through hole of the top seat of the seat frame, and is clamped and fixed by the upper and lower nuts. The guide rod is screwed on the seat frame, see figure 7.

The two bearings are placed in the counterbore in the middle of the leveling frame, and the radial screws on the leveling frame are used to squeeze the outer ring of the bearings so that the bearings and the frame are tightly fitted, as shown in Figure 9. The rotating shaft rod of the measuring rod is strung through the inner diameters of the two bearings, the protrusion on the rotating shaft rod of the rotating bracket is pressed on the inner ring of the upper bearing, and the gap between the rotating shaft rod and the inner diameter of the lower bearing is eliminated by stuffing a thin iron sheet so that the rotating shaft rod and Bearing bore tight fit, see Figure 11.

Step Three: Sensor Installation

Mount a laser displacement sensor on the spreader end of the measuring rod. The laser displacement sensor is fixedly connected to the measuring rod through the threaded connection hole processed on the measuring rod, and the direction of the laser is the axial direction of the spreading rod, as shown in Figure 11.

The angle sensor housing is installed on the seat frame, and the test shaft of the angle sensor is connected with the axis of the measuring rod, as shown in Figure 12, for measuring the angle of rotation of the measuring rod.

Step 4: Engine Nozzle Placement and Leveling

Use a crane to lift the nozzle, with the nozzle of the engine facing down, and the nozzle falls slowly. During the docking process, observe that the shape of the nozzle is consistent with the distance from the three guide rods. The plates do not move relative to each other.

By rotating the nut of the upward adjustment plate, the upward adjustment plate is raised and lowered, and the angle of the nozzle mouth is measured with a level ruler, so as to adjust the nozzle mouth to be in a horizontal state.

The fifth step is to measure the radial distance and rotation angle of the truncated circle of the engine nozzle

Connect the power supply to the sensor and connect the signal recorder to check the laser beam emitted by the laser displacement sensor. The recorder can normally receive the displacement signal of the laser displacement sensor and the angle signal of the angle sensor, and can carry out the measurement of the nozzle axis. During the measurement process, use the manual to rotate the rotating bracket slowly and roughly at a constant speed, and the measurement ends after one rotation. Check the measured rotation angle data (see Figure 14) and all laser displacement data.

Step 6: Engine Nozzle Axis Analysis

The distance r between the laser point (on the truncated circle) and the rotating shaft inside the nozzle is obtained by adding the distance between the sensor installation point and the rotating shaft to the laser displacement measurement data (see Figure 15). The measurement data unit of the rotation angle is degree, which needs to be converted into radian w. According to the distance r and the rotation angle w, the least square method is used to fit each intercepted circle and the center of the circle, the relationship curve of the angle-distance and the intercepted circle (fitting circle) and the center of the circle. See Figure 16. The distance r and the rotation angle w are fitted by the least square method to obtain the truncated circle and the center of the circle. The axes of the nozzles are obtained by connecting the centers of the truncated circles. Figure 17 shows the four truncated circles and the axes of the nozzles.

The system and method for measuring the axis of an engine nozzle proposed by the invention can also be used for axis measurement and roundness measurement of other rotating casing parts.

The measurement system and method of the engine nozzle axis proposed by the present invention realize the non-contact measurement of the engine nozzle axis, avoid the damage caused by the contact measurement to the inner wall of the nozzle, and obtain the engine nozzle inner wall through a plurality of laser displacement sensors. The radial distance of multiple truncated circles of the wall is used to obtain the rotation angle of the measuring rod through the angle sensor, and the axis of the nozzle is obtained according to the radial distance of the multiple truncated circles and the rotational angle of the measuring rod, and the measurement result is accurate.

Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention. within the bounds of the requirements.

Claims (10)

1. the measurement system of an engine jet pipe axis, it is characterised in that including:

Leveling mounting (1) and rotary measurement device (2)；

Described rotary measurement device (2) includes measuring bar (21), described measurement bar (21) week To rotation；

Described measurement bar (21) is provided with angular transducer (22) and multiple laser displacement sensing Device (23)；

The plurality of laser displacement sensor (23) is positioned at the different high of described measurement bar (21) On degree, for measuring the nozzle wall radial distance with corresponding laser displacement sensor；

Described angular transducer (22) is positioned on described measurement bar (21), is used for measuring described Measure the anglec of rotation of bar (21)；

Described measurement bar (21) is vertically arranged on described leveling mounting (1)；

Described leveling mounting (1) contacts with the spout of engine jet pipe.

The measurement system of engine jet pipe axis the most according to claim 1, its feature exists In, also include signal record and processor；

Described signal record and processor and described angular transducer (22) and multiple laser displacement Sensor (23) is connected, for sensing with corresponding laser displacement according to the inwall of described jet pipe The radial distance of device and the anglec of rotation of described measurement bar (21) obtain the axis of described jet pipe.

The measurement system of engine jet pipe axis the most according to claim 1, its feature exists In, described leveling mounting (1) includes clutch shaft bearing (11) and the second bearing (12)；

Described measurement bar (21) includes rotating shaft bar (211) and multiple exhibition bar (212)；

Described rotating shaft bar (211) passes described clutch shaft bearing (11) and described second bearing (12) It is vertically arranged on described leveling mounting (1)；

The plurality of laser displacement sensor (23) is respectively arranged at the plurality of exhibition bar (212) On.

The measurement system of engine jet pipe axis the most according to claim 3, its feature exists In,

Described angular transducer (22) is positioned at the bottom of described rotating shaft bar (211), described angle The rotating shaft of degree sensor (22) is connected with the axle center of described rotating shaft bar (211).

The measurement system of engine jet pipe axis the most according to claim 3, its feature exists It is shaped as triangle in, described leveling mounting (1).

The measurement system of engine jet pipe axis the most according to claim 3, its feature exists In, described measurement bar (21) is positioned at the pre-centration axis of the measurement system of engine jet pipe axis On line.

The measurement system of engine jet pipe axis the most according to claim 3, its feature exists In, also include:

Three upper posture adjustment plates (13) and three guide posts (15)；

Described upper posture adjustment plate (13) is arranged on described leveling mounting (1), is used for and starts The spout of machine jet pipe contacts, and regulation spout is in level；

Described three guide posts (15) are vertically arranged in described three upper posture adjustment plates (13) respectively On position away from described measurement bar (21), it play the guiding role with the placement to engine jet pipe.

The measurement system of engine jet pipe axis the most according to claim 3, its feature exists In, also include:

Three lower posture adjustment plates (14)；

Described three lower posture adjustment plates (14) are arranged at the bottom of described leveling mounting (1), use It is in level in regulation leveling mounting (1).

9. the measurement system of the engine jet pipe axis that a kind utilizes described in any one of claim 1-8 The measuring method of the engine jet pipe axis of system, it is characterised in that including:

Obtain the radial distance of nozzle wall and corresponding laser displacement sensor；

Obtain the anglec of rotation measuring bar；

The radial distance of the inwall according to described jet pipe and corresponding laser displacement sensor and institute The anglec of rotation stating measurement bar obtains the center of circle of multiple sections of circles, connects each section of round heart acquisition and starts Machine nozzle axis.

The measuring method of engine jet pipe axis the most according to claim 9, its feature It is, the radial distance of the described inwall according to described jet pipe and corresponding laser displacement sensor With the center of circle that the anglec of rotation of described measurement bar obtains multiple sections of circles, including:

Use least square fitting method that the inwall of described jet pipe is sensed with corresponding laser displacement The radial distance of device and the anglec of rotation of described measurement bar are fitted, and obtain the circle of multiple sections of circles The heart.