CN214308568U

CN214308568U - Area measuring device and nozzle throat area measuring device

Info

Publication number: CN214308568U
Application number: CN202120823601.8U
Authority: CN
Inventors: 时文斌; 王秋阳; 田锦; 王瑛琦
Original assignee: AECC Commercial Aircraft Engine Co Ltd
Current assignee: AECC Commercial Aircraft Engine Co Ltd
Priority date: 2021-04-21
Filing date: 2021-04-21
Publication date: 2021-09-28
Anticipated expiration: 2031-04-21

Abstract

An area measuring device includes a caliper including a pair of movable jaws for showing a distance between the pair of jaws, a scale, and an angle measuring device; the scale comprises a measuring head, the measuring head is movably and rotatably arranged on the clamping jaw through a pivot, the distance between the pivot and the measuring head is adjustable, and the scale is used for showing the distance between the pivot and the measuring head; the angle measuring device is used for measuring the rotation angle of the scale relative to the clamping jaw. The measuring result of the area measuring device can quickly obtain the real throat area of the spray pipe based on the actual assembly state, and the area measuring device is easy to assemble and disassemble and convenient to carry. A device for measuring the area of the throat of the spray pipe is also provided.

Description

Area measuring device and nozzle throat area measuring device

Technical Field

The utility model relates to an area measurement device, concretely relates to area measurement of spray tube throat.

Background

On an aircraft gas turbine engine, a tail nozzle mainly has the functions of expanding and accelerating high-temperature and high-pressure gas behind a turbine and discharging the gas out of the engine, converting available work of the gas into kinetic energy, and ejecting the gas backwards at high speed so as to enable the engine to generate reaction thrust.

The tail nozzle can be divided into a convergent type and a convergent-divergent type according to the molded surface of a flow passage. The convergent-divergent nozzle is a supersonic nozzle, and for a low-mach number turbofan engine with a large bypass ratio, a convergent nozzle is generally adopted, and the structure of the convergent nozzle is shown in fig. 1 and mainly comprises a tail nozzle 1 and a central cone 2.

The area of the throat of the tail nozzle is an annular area formed by taking the tail nozzle 1 as a perpendicular line perpendicular to the surface of the central cone 2. The size of the throat area of the tail nozzle can change the expansion ratio distribution of the airflow in the turbine and the nozzle, so as to change the common working point of the compressor and the turbine, further change the working state of the whole engine and ensure that the engine obtains good performance.

Thus, the throat area of the jet is an important parameter affecting engine performance. The accurate measurement of the throat area of the jet pipe of the aircraft engine is the key for matching the performance of the engine and improving the efficiency of the engine. Particularly, in the engine test stage, due to the requirement of performance debugging, a mode of replacing spray pipes with different areas is generally adopted. Therefore, how to measure the actual nozzle throat area quickly and accurately is very important. The throat area of the jet nozzle is directly determined by the installation positions of the jet nozzle 1 and the central cone 2, the installation positions of the jet nozzle 1 and the central cone 2 are determined by the jet nozzle installation edge 6 and the central cone installation edge 7, and the jet nozzle installation edge 6 and the central cone installation edge 7 generally have a certain axial height difference due to factors such as manufacturing tolerance, assembly process and the like, so that the real throat area needs to be measured in an assembly state.

The throat area of the existing commonly used spray pipe is generally obtained by respectively measuring the diameter of the tail spray and the diameter of the outer wall surface of the central cone by three coordinates, but because the mounting edges of the tail spray and the central cone usually have certain axial height difference due to factors such as manufacturing tolerance, assembly process and the like, errors caused by the factors cannot be accurately considered by three-coordinate measurement; and the three-coordinate measurement has poor economy and complex operation, and has the problems of inconvenient disassembly, assembly, carrying and the like for the engine outfield test.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide an area measurement device, can be fast accurate measure true throat area.

The area measuring device comprises a caliper, a scale and an angle measuring device, wherein the caliper comprises a pair of movable clamping jaws for showing the distance between the pair of clamping jaws; the scale comprises a measuring head, the measuring head is movably and rotatably arranged on the clamping jaw through a pivot, the distance between the pivot and the measuring head is adjustable, and the scale is used for showing the distance between the pivot and the measuring head; the angle measuring device is used for measuring the rotation angle of the scale relative to the clamping jaw.

In one or more embodiments, the pawl includes a first runner and the scale includes a second runner, the pivot slidably and rotatably engaged with the first runner, the pivot slidably engaged with the second runner.

In one or more embodiments, the pivot is T-shaped, including a shaft portion and a cap portion, the cap portion engaging the second sliding slot, the shaft portion engaging the first sliding slot.

In one or more embodiments, the first runner is a through slot that passes through the pawl.

In one or more embodiments, the first runner is a counter bore runner.

In one or more embodiments, the angle measuring device is a goniometer disposed on the scale surface.

In one or more embodiments, the angle measuring device is an encoder including a code wheel configured to rotate along with the scale and a photo detector configured to recognize rotation of the code wheel and output the rotation angle.

In one or more embodiments, the caliper is adjustable in length.

Another object of the utility model is to provide a spray tube throat area measurement device, above-mentioned spray tube throat area measurement device the spray tube throat is enclosed by central awl and tail-nozzle, spray tube throat area measurement device includes above-mentioned area measurement device, the tip of a pair of jack catch is used for supporting the inner fringe face of tail-nozzle, the gauge head is used for following the perpendicular line direction on central awl surface supports the outer wall of central awl, angle measurement device is used for measuring the gauge head supports during the outer wall face the scale for the turned angle of jack catch.

Above-mentioned area measurement device directly measures the jet-tail pipe diameter through slide caliper rule, obtains central awl diameter through scale and angle measuring device's measurement and calculation, and further calculation obtains annular nozzle throat area, because the measuring result is based on the assembly state of reality, consequently can be real reaction actual nozzle throat area, and area measurement device dismouting, convenient to carry effectively improve measurement of efficiency.

Drawings

The above and other features, properties and advantages of the present invention will become more apparent from the following description of the embodiments with reference to the accompanying drawings, in which:

fig. 1 is a schematic structural view of an area measuring apparatus.

Fig. 2 is a partially enlarged view of the area a in fig. 1.

FIG. 3 is a simplified diagram of the area of the nozzle throat.

Description of symbol mark

1 tail nozzle

2 center cone

3 callipers

4 encoder

5 staff gauge

6 tail nozzle mounting edge

7 center cone mounting edge

8-pivot

9 measuring head

10 first chute

14-degree measuring device

Side area of 20 round table

31 claw

32 end of the tube

101 inner edge surface

201 outer wall surface

Detailed Description

The present invention will be further described with reference to the following embodiments and drawings, and more details will be set forth in the following description in order to provide a thorough understanding of the present invention, but it is obvious that the present invention can be implemented in various other ways different from those described herein, and those skilled in the art can make similar generalizations and deductions according to the actual application without departing from the spirit of the present invention, and therefore, the scope of the present invention should not be limited by the contents of the embodiments. It should be noted that these and other figures are given by way of example only and are not drawn to scale, and should not be construed as limiting the scope of the invention as it is actually claimed.

Fig. 1 to 2 show a measuring device for measuring an area, comprising a caliper 3, a scale 5 and an angle measuring device 14. The caliper 3 includes a pair of movable jaws 31, and the caliper 3 can show a distance C11 between the pair of jaws 31. The scale 5 comprises a measuring head 9, which is movably and rotatably arranged on the jaw 31 through a pivot 8, and the distance between the pivot 8 and the measuring head 9 is adjustable, and the scale 5 is used for showing the distance between the pivot 8 and the measuring head 9. The angle measuring device 14 is used to measure the rotation angle θ of the scale 5 relative to the pawl 31. When the distance C11 between the pair of claws 31, the distance between the pivot shaft 8 and the gauge head 9 for indicating the vertical line, and the rotation angle θ of the scale 5 with respect to the claws 31 are obtained, the annular measurement area can be calculated.

The area measuring device can be applied to the measurement of the enclosed area of a ring-shaped part, for example, the throat area of a nozzle. Referring to fig. 1, the nozzle throat of the aircraft engine exhaust nozzle is enclosed by a central cone 2 and an exhaust nozzle 1, and the area of the nozzle throat refers to an annular area formed by circumferentially surrounding the outlet of the exhaust nozzle 1 by a perpendicular line perpendicular to the surface of the central cone 2.

It can be understood from fig. 1 and 2 that the area measuring device is applied to the measurement of the area of the nozzle throat, and the device can directly realize the measurement of the area of the nozzle throat in the assembled state of the engine. The end portions 32 of the pair of claws 31 are adapted to abut against the inner peripheral surface 101 of the tail nozzle 1, the gauge 9 is adapted to abut against the outer wall surface 201 of the center cone 2 in the direction of the perpendicular to the surface of the center cone 2, and the scale 5 obtains a distance C12 between the pivot 8 and the gauge 9, which is the distance between the inner peripheral surface 101 of the tail nozzle 1 and the outer wall surface 201 of the center cone 2 in the direction of the perpendicular when the distance C12 is at a minimum. The angle measuring device 14 measures a rotation angle θ of the scale 5 with respect to the jaws 31 when the gauge 9 abuts against the outer wall surface 201 of the center cone 2. The rotation angle θ is calculated in such a manner that the state when the scale 5 is perpendicular to the engine axis is 0 °, and the rotation angle θ of the scale 5 with respect to the pawl 31 is the relative angle of the scale 5 with respect to the state perpendicular to the engine axis.

It should be noted that the position of the pivot 8 on the scale 5 is close to the inner edge surface 101 of the jet nozzle 1, and therefore the distance C12 between the pivot 8 and the gauge head 9 and the distance between the inner edge surface 101 of the jet nozzle 1 and the outer wall surface 201 of the center cone 2 in the vertical direction can be approximately equal, and the error thereof is within a reasonable range in the following calculation and therefore can be ignored.

One embodiment of the caliper 3, the scale 5 and the angle measuring device 14 is shown in fig. 2, the jaw 31 includes a first slide groove 10, the scale 5 includes a second slide groove (not shown), the pivot 8 slidably and rotatably engages with the first slide groove 10, and the pivot 8 slidably engages with the second slide groove. In one embodiment, for example, the pivot 8 is T-shaped, including a shaft portion and a cap portion. The cap cooperates with the second runner on the scale 5 and the shaft cooperates with the first runner 10 on the jaw 31, so that the pivot 8 can be rotated and displaced simultaneously in the first runner 10 by the shaft, while displacement on the scale 5 is effected by the cap, but not by rotation. The scale 5 is movably and rotatably arranged on the claw 31 through the pivot 8, and the distance between the measuring head 9 and the outer wall surface 202 of the center cone 2 is adjusted through the cooperation of the pivot 8 and the second sliding chute.

On the basis of the above embodiment, an embodiment of the first sliding chute 10 is a through groove penetrating through the jaw 31, a shaft portion of the pivot 8 is provided with a thread, and after the shaft portion extends through the first sliding chute 10, the shaft portion is respectively matched with the shaft portion through nuts along the upper and lower directions of the first sliding chute 10, so that the pivot 8 is fixed at a certain position of the first sliding chute 10, and the scale 5 is fixed on the jaw 31, thereby facilitating subsequent accurate measurement.

Another embodiment of the first sliding groove 10 is a counter bored groove on the jaw 31, the shaft of the pivot 8 is provided with a thread, and the shaft is fastened by a nut located above the first sliding groove 10 after extending into the first sliding groove 10, and can also play a role in fixing the scale 5 on the jaw 31.

The connection manner of the caliper 3, the scale 5 and the angle measuring device 14 includes but is not limited to the above examples, for example, in other embodiments, the jaw 31 provides a groove matched with the pivot 8, the scale 5 is rotatably connected with one end of the pivot 8 and is arranged to be telescopic along the direction of the own axis, the distance from the measuring head 9 to the outer wall surface 201 of the center cone 2 can be adjusted, and the rotation angle of the scale 5 relative to the jaw 31 can be effectively obtained.

The angle measuring device 14 is used for acquiring the rotation angle of the scale 5 relative to the jaw 31, and one embodiment of the angle measuring device 14 is an angle ruler arranged on the surface of the scale 5. The angle scale is set to 0 degree along the extending direction of the caliper 3, and when the scale 5 is measured along the perpendicular direction of the surface of the central cone 2, the included angle formed by the scale 5 and the 0 degree is the rotation angle theta of the scale 5 relative to the clamping jaw 31. The rotation angle of the scale 5 relative to the claw 31 can be directly read by using the angle ruler, and the structure is simple and the use is convenient.

Another embodiment of the angle measuring device 14 is an encoder 4, as shown in fig. 2. The encoder 4 includes a code wheel for rotating together with the scale 5 and a photoelectric detection device for recognizing the rotation of the code wheel and outputting a rotation angle θ. The position of the scale 5 perpendicular to the claws 31 is set as the initial position, and when the code wheel rotates along with the scale 5, the photoelectric detection device detects the rotation angle of the code wheel, so that the rotation angle theta of the scale 5 relative to the claws 31 is obtained. By using the encoder 4, the rotation angle of the scale 5 with respect to the claw 31 can be accurately obtained with high accuracy. The angle measuring device 14 includes, but is not limited to, the above-described embodiments, and can be applied to the present disclosure as long as it is a device that effectively measures an angle.

Preferably, the length of the caliper 31 is adjustable, and the length can be selected according to specific measuring parts, so that the caliper has wider application.

The specific measurement steps of the area measurement device are described below in conjunction with the nozzle throat shown in FIG. 1.

First, the end portions 32 of the pair of claws 31 are pressed against the inner peripheral surface 101 of the nozzle 1, and the distance between the pair of claws 31 is read on the caliper 3, that is, the diameter C11 of the nozzle 1 is obtained.

Subsequently, the scale 5 provided on the claw 31 is rotated, and the stylus 9 at one end of the scale 5 is moved back and forth in the direction B shown in fig. 2, and the distance between the stylus 9 and the pivot shaft 8 is read in real time by the scale 5. When the distance is minimized, indicating that the scale 5 is pressed against the outer wall surface 201 of the center cone 2 in the direction of the vertical line, the vertical distance C12 between the jet nozzle 1 and the center cone 2 is obtained by reading the scale 5.

When the scale 5 abuts against the outer wall surface 201 of the center cone 2 in the direction of the perpendicular line, the rotation angle θ detected by the angle measuring device 14 is acquired.

And after the parameters are obtained, calculating the area of the throat of the spray pipe. The nozzle throat area is defined by the circumferential length L1 of the inner edge surface 101 of the jet nozzle 1 where measured, the circumferential length L3 of the center cone 2 where measured, and the distance L2 between the inner edge surface 101 of the jet nozzle 1 and the outer wall surface 201 of the center cone 2 in the vertical direction, and thus can be converted into the circular truncated cone side area 20 shown in fig. 3.

The radius of the measured position of the tail nozzle 1 is C11/2, the distance L2 is the vertical distance C12, the calculation mode of the radius of the measured position of the central cone is (C11-2C12cos theta)/2, and after the radius is obtained, the area 20 of the circular truncated cone side is S ═ π C12(C11-C12cos theta), namely the area of the nozzle throat.

In order to improve the measurement precision, the area measurement device can be rotated to different angles in the circumferential direction for multiple measurements, and the areas of the plurality of nozzle throats are obtained and averaged to obtain a more accurate area of the nozzle throat.

The diameter of the tail nozzle is directly measured by the caliper by adopting the area measuring device, and the diameter of the central cone is obtained by measuring and calculating the ruler and the angle measuring device, so that the real throat area of the nozzle can be obtained based on the actual assembly state. The area measuring device is convenient to disassemble, assemble and carry, can quickly measure the throat area of the spray pipe in the test process, and is good in economy, simple and easy to operate.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. For example, the way in which the scale is rotated with respect to the jaws, the type of encoder selected, etc. Therefore, any modification, equivalent changes and modifications made to the above embodiments according to the technical spirit of the present invention, all without departing from the content of the technical solution of the present invention, fall within the scope of protection defined by the claims of the present invention.

Claims

1. An area measurement device, comprising:

a caliper (3) comprising a pair of movable jaws (31) for showing a distance between the pair of jaws (31);

the scale (5) comprises a measuring head (9) and is movably and rotatably arranged on the clamping jaw (31) through a pivot (8), the distance between the pivot (8) and the measuring head (9) is adjustable, and the scale (5) is used for showing the distance between the pivot (8) and the measuring head (9); and

and the angle measuring device (14) is used for measuring the rotation angle of the scale (5) relative to the clamping jaw (31).

2. Area measuring device according to claim 1, characterised in that the pawl (31) comprises a first runner (10) and the scale (5) comprises a second runner, the pivot (8) being slidably and rotatably engaged with the first runner (10), the pivot (8) being slidably engaged with the second runner.

3. Area measuring device according to claim 2, characterised in that the pivot (8) is T-shaped and comprises a shaft part and a cap part, the cap part engaging the second runner and the shaft part engaging the first runner (10).

4. Area measuring device according to claim 3, characterised in that the first runner is a through slot through the jaw (31).

5. The area measurement device of claim 3, wherein the first runner is a counter bore runner.

6. Area measuring device according to claim 1, characterised in that the angle measuring means (14) is a goniometer arranged on the surface of the scale (5).

7. The area measuring device according to claim 1, wherein the angle measuring means (14) is an encoder (4), the encoder (4) includes a code wheel for following the rotation of the scale (5) and a photo-detecting means for recognizing the rotation of the code wheel and outputting the rotation angle.

8. Area measuring device according to claim 1, characterised in that the length of the caliper (3) is adjustable.

9. A nozzle throat area measuring device, the nozzle throat being enclosed by a central cone (2) and a nozzle (1), characterized in that it comprises an area measuring device according to any one of claims 1 to 8,

the pair of claws (31) is used for abutting against the inner edge surface (101) of the tail nozzle (1),

the measuring head (9) is used for propping against the outer wall surface (201) of the center cone along the direction of the perpendicular line of the surface of the center cone (2),

the angle measuring device (14) is used for measuring the rotation angle of the scale (5) relative to the clamping jaw (31) when the measuring head (9) abuts against the outer wall surface (201).