Cabin door hinge moment measuring device

Abstract

A cabin door hinge moment measuring device relates to the field of aviation weather dynamic test measuring equipment and comprises a cabin door, a hinge moment balance, a cabin, a cabin door front connecting rod and a cabin door rear connecting rod. The hinge moment balance adopts a symmetrical integral structure with a fixed middle part and double series connection on two sides, and comprises a fixed connecting end, a combined element, a balance element transition section, a normal force element and a model connecting end, the cabin door is fixedly connected with the balance through the cabin door front connecting rod and the cabin door rear connecting rod, that is, the two cantilever ends of the balance are connected with the measuring cabin door, so that the connecting supporting rigidity of the measured cabin door is increased, and the influence on balance elements when the cabin door is subjected to load deformation is reduced. According to the cabin door hinge moment measuring device, the problem that measurement data of a traditional hinge moment balance is inaccurate is solved, and high-precision measurement of the cabin door hinge moment of an aircraft model in a wind tunnel test is achieved.

Description

Technical Field

[0001] The invention belongs to the field of aerospace aerodynamic test and measurement equipment, and in particular relates to a door hinge torque measurement device. Background Art

[0002] With the strengthening of my country's independent innovation of aircraft, aircraft continue to emerge, which puts forward higher requirements for the precision, accuracy and refinement of wind tunnel force test, especially the requirements for the quality of hinge torque test data. The balance is the key to the success of the hinge torque test, which plays a decisive role in the control surface hinge torque test capability and force measurement accuracy.

[0003] In the door hinge torque force measurement test of a certain aircraft model, since the door is thin and narrow, the load on the balance is extremely mismatched, the normal force output signal is small, and the resolution is low; at the same time, the connection and assembly stress will also reduce the accuracy of the balance measurement; when conducting wind tunnel tests, a traditional leaf hinge torque balance is used to measure the door hinge torque. Not only is the rigidity of the balance as a supporting component of the door relatively small, but the door also deforms greatly under the action of aerodynamic loads, resulting in serious model distortion problems, which seriously affects the data quality. Summary of the invention

[0004] The purpose of the present invention is to address the problems encountered in the force measurement test of the door hinge torque of a certain aircraft model mentioned above, overcome the insufficient measurement accuracy of the traditional leaf hinge torque balance, and propose a door hinge torque measurement device to achieve high-precision measurement of the door hinge torque of the aircraft model in the wind tunnel test.

[0005] The technical solutions provided by this application are as follows:

[0006] A door hinge torque measuring device includes a door, a hinge torque balance, a cabin, a cabin bottom cover, a rectifier, a door front connecting rod, a door middle connecting rod and a door rear connecting rod, etc.; the hinge torque balance includes a fixed connection end, both ends of which are sequentially connected to a combination element, a balance element transition section, a normal force element and a model connection end; the fixed connection end is fixedly connected to the cabin, and the door front connecting rod and the door rear connecting rod are connected to the front and rear of the door, and the other ends of the door front connecting rod and the door rear connecting rod are respectively fixedly connected to the model connection end; the cabin 3 is provided with a cabin bottom cover and is fixedly connected to it by screws. The door is provided with a first rectangular groove and a third rectangular groove that are not connected, and the first rectangular groove and the third rectangular groove are respectively transitionally matched with the rectangular protrusion connection ends at one end of the door front connecting rod and the door rear connecting rod.

[0007] The hatch door is also connected to a hatch middle connecting rod, and a second rectangular groove is provided on the hatch door. One end of the hatch middle connecting rod is connected to the second rectangular groove, and the other end of the hatch middle connecting rod is suspended above the hinge torque balance, with a minimum spacing of about 1mm; when measuring the hinge torque exerted on the 0° hatch door, there is no second rectangular groove on the hatch door and the hatch middle connecting rod is not connected.

[0008] A straight circular flexible hinge is provided on the side of the model connection end close to the normal force element. The minimum distance from the screw holes at both ends of the balance fixed connection end to the combined element is ≥10mm

[0009] There is a gap between the transition section of the balance element and the model connection end and the cabin.

[0010] The combined element includes a plurality of measuring beams connected between the fixed connection end and the transition section of the balance element. The measuring beams are rectangular beams having an upper surface and a lower surface parallel to each other, and two side surfaces parallel to each other. The upper surface and the lower surface of the rectangular beam are parallel to the surface of the cabin part facing them, and a strain gauge is attached to the upper surface and the lower surface of each rectangular beam.

[0011] There are eight measuring beams, and each end of the fixed connection end is connected to four measuring beams; the two outer measuring beams have the same height and width, and the two inner measuring beams have the same height and width; the height of the outer measuring beams is smaller than that of the inner measuring beams, and the widths are equal.

[0012] The normal force element comprises an "I"-shaped measuring beam and a support beam, both of which are connected between the transition section of the balance element and the cabin door connection end, the support beams are symmetrically arranged on both sides of the middle "I"-shaped measuring beam, the support beam is a rectangular structure formed by a plurality of spring sheets arranged in parallel and at intervals, and the arrangement direction of the plurality of spring sheets in each support beam is parallel to the thickness direction of the "I"-shaped measuring beam, and the thickness direction of the "I"-shaped measuring beam is perpendicular to the surface of the cabin it faces; the width of the two end parts of the "I"-shaped measuring beam is greater than the width of the middle structure, and strain gauges are respectively pasted on the upper and lower surfaces of both sides of the two end parts of the "I"-shaped measuring beam (241).

[0013] Preferably, there is an arc-shaped flexible hinge 1 on the outer side of the transition section of the balance element connected to the normal force element support beam; and there is an arc-shaped flexible hinge 2 on the outer side of the model connection end connected to the normal force element support beam.

[0014] There is a chamfer between the side surface of the measuring beam and the end surface of the cabin connection end and the transition section of the balance element; the arrangement direction of the "I"-shaped measuring beam and the supporting beam is the width direction of the "I"-shaped measuring beam and the supporting beam, and there is a chamfer between the two sides of the width direction of the "I"-shaped measuring beam and the end surface of the cabin connection end and the transition section of the balance element.

[0015] In summary, this application at least includes the following beneficial technical effects:

[0016] 1) The hinged moment balance of the present invention adopts a symmetrical integral structure with a middle fixed and double-series connection on both sides, which shortens the distance from the design center of the balance to the hatch door shaft, reduces the additional moment, and enables the balance to obtain better load matching.

[0017] 2) The hinge torque balance elements of the present invention are designed on both sides of the fixed connection end, and the two cantilever ends of the balance are connected to the measuring cabin door, which increases the connection support stiffness of the measured cabin door; and the balance element is a cantilever beam relative to the fixed end. When the cabin door is deformed under load, the impact on the balance element is very small, thereby improving the measurement accuracy of the balance.

[0018] 3) The hinge torque balance of the present invention is separately provided with a normal force element for measuring small-range normal force. Under the action of axial force, hinge torque and rolling torque, the measuring beam hardly deforms, the normal force component has a strong anti-interference ability, and the measurement accuracy of small normal force is improved.

[0019] 4) The flexible hinge is applied to the design of the hinge torque balance of the present invention, which not only reduces the influence of interference stresses such as screw preload and door load deformation on the signal output of the hinge torque balance; at the same time, it greatly reduces the interference of axial force, hinge torque and rolling torque on the measurement of small normal force, thereby improving the measurement accuracy of the balance.

[0020] 5) The hinge torque balance of the present invention is a combined bridge type, in which each group of measuring elements is independently composed of a measuring bridge. The signal outputs of the normal force, axial force, hinge torque and rolling torque felt by the measuring door are respectively composed of different combinations of the signal outputs of each measuring bridge. This method increases the sensitivity of each element of the balance and improves the measurement accuracy of the balance.

[0021] 6) The present invention provides a feasible low-speed wind tunnel test technical solution for measuring the door hinge torque. The overall structural rigidity of the present invention is good, and the balance elements are symmetrically arranged, so that the relative position of the door and the cabin after loading is guaranteed, and the measurement accuracy of the experimental data is high and more real and reliable. The door angle does not need to be changed to replace the hinge torque balance, which greatly saves the test cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the present invention;

[0023] Figure 2 This is a schematic diagram of the hatch structure of the present invention;

[0024] Figure 3 This is a schematic diagram of the front connecting rod structure of an angled hatch according to the present invention;

[0025] Figure 4This is a schematic diagram of the connecting rod structure of an angled hatch according to the present invention;

[0026] Figure 5 This is a schematic diagram of the rear connecting rod structure of an angled hatch according to the present invention;

[0027] Figure 6 This is a front view of the hinge moment balance of the present invention;

[0028] Figure 7 for Figure 6 AA section view;

[0029] Figure 8 for Figure 6 The enlarged view of point D;

[0030] Fig. 9 for Figure 7 BB cross-sectional view;

[0031] Fig.10 for Figure 7 CC cross-sectional view.

[0032] Explanation of the reference numerals: 1. Cabin door; 2. Hinge moment balance; 3. Cabin; 4. Cabin bottom cover; 5. Rectifier; 6. Cabin door front connecting rod; 7. Cabin door middle connecting rod; 8. Cabin door rear connecting rod. 11-First rectangular groove on cabin door 1; 12-Second rectangular groove on cabin door 1; 13-Third rectangular groove on cabin door 1. 31-Circular hole for wiring. 21-Fixed connection end; 22-Combined element; 23-Transition section of balance element; 24-Normal force element; 25-Model connection end. 211-Screw hole; 221-Inner measuring beam; 222-Outer measuring beam; 231-Circular hole for wiring; 232-Arc-type flexible hinge 1; 241-"I"-shaped measuring beam; 242-Supporting beam; 251-Straight circular flexible hinge; 252-Arc-type flexible hinge 2. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments disclosed in the present invention will be further described in detail below with reference to the accompanying drawings.

[0034] The present application embodiment discloses a door hinge torque measuring device, such as Figure 1 As shown, it includes a cabin door 1, a hinge moment balance 2, a cabin 3, a cabin bottom cover 4, a fairing 5, a cabin door front connecting rod 6, a cabin door middle connecting rod 7 and a cabin door rear connecting rod 8, etc.

[0035] like Figure 2 , Figure 3 , Figure 4 and Figure 5As shown, the door 1 is provided with a first rectangular groove 11, a second rectangular groove 12 and a third rectangular groove 13 which are not connected from front to back, and are respectively fixedly connected to the rectangular protrusion ends of the door front link 6, the door middle link 7 and the door rear link 8 by screws, and the first rectangular groove 11 and the third rectangular groove 13 are respectively transitionally matched with the rectangular protrusion ends of the door front link 6 and the door rear link 8 to prevent the thin-walled door 1 from being deformed due to over-constraint, thereby affecting the accuracy of the door hinge torque measurement. In order to simulate the real shape of the aircraft model door, the other end of the door middle link 7 is suspended above the hinge torque balance 2, with a minimum spacing of about 1mm; the other ends of the door front link 6 and the door rear link 8 are fixedly connected to the hinge torque balance 2. The hinge torque balance 2 is fixedly connected to the cabin 3 by screws and pins.

[0036] In order to facilitate the installation and disassembly of the hinge torque balance 2 and meet the requirements of small-angle cabin door installation, a cabin bottom cover 4 is opened on the cabin 3 and fixed thereto by screws, and a wiring circular hole 31 for the hinge torque balance 2 is left at the lower rear side of the cabin 3.

[0037] Different door front connecting rods 6, door middle connecting rods 7 and door rear connecting rods 8 are replaced between the door 1 and the hinge moment balance 2, so that different angles are formed between the door 1 and the cabin 3.

[0038] like Figure 6 and Figure 7 As shown, the hinge moment balance 2 adopts a double-series symmetrical integral structure with a middle fixed on both sides, including a fixed connection end 21, a combination element 22, a balance element transition section 23, a normal force element 24 and a model connection end 25, that is, two door connection ends 25, two normal force elements 24, two balance element transition sections 23 and two combination elements 22 are symmetrically arranged on both sides of the fixed connection end 21 fixedly connected to the cabin 3 in the middle. The combination element 22 is connected in series with the normal force element 24 through the balance element transition section 23, and is symmetrically arranged between the fixed connection end 21 and the model connection end 25.

[0039] like Figure 1 and Figure 6 As shown, the structure of the hinged moment balance 2 shortens the distance from the balance design center to the door rotation axis, reduces the additional torque, and enables the balance to obtain better load matching. At the same time, the thin-walled door 1 is fixedly connected to the two model connection ends 25 of the balance through the other ends of the door front connecting rod 6 and the door rear connecting rod 8, that is, the two cantilever ends of the balance are connected to the measured door, which increases the connection support stiffness of the measured door 1. In addition, the balance element is designed on both sides of the fixed connection end. Since the balance element is a cantilever beam relative to the fixed end, when the door is loaded and deformed, the impact on the balance element is very small, which improves the measurement accuracy of the balance.

[0040] The bottom surfaces of the front-to-back symmetrical balance element transition section 23 and the door connection end 25 are non-contact surfaces, that is, there is a gap between the bottom surfaces of the balance element transition section 23 and the door connection end 25 and the cabin 3. This ensures that the forces and moments borne by the cabin door during the test are transmitted to the cabin through the balance element. A straight circular flexible hinge 251 is provided on the side of the model connection end 25 close to the normal force element 24. The straight circular flexible hinge (251) is composed of two semi-cylindrical grooves opened on the upper and lower surfaces of the model connection end (25) and symmetrically distributed. The two semi-cylindrical grooves are along the direction perpendicular to the normal force element (24). This flexible hinge has no gap in the mechanical structure and has elastic restoring force, which can greatly reduce the influence of interference stresses such as screw pre-tightening force and load deformation of the model cabin 3 on the signal output of the hinge torque balance 2.

[0041] The minimum distance between the screw holes 211 at both ends of the fixed connection end 21 and the combined element 22 is ≥10 mm to reduce the influence of the screw pre-tightening force on the balance element.

[0042] like Figure 6 — Fig.10 As shown, the balance element of the hinge moment balance 2 includes a combination element 22 and a normal force element 24. The hinge moment balance is separately provided with a normal force element, which effectively solves the problem that the normal force on the hatch is small and the load on the balance is extremely mismatched.

[0043] The combined element 22 is composed of symmetrically arranged measuring beams, which are divided into a plurality of (preferably four according to the structural characteristics of the balance and the load size) rectangular beams of similar height and width, the rectangular beams having mutually parallel upper and lower surfaces, and two mutually parallel side surfaces, the upper and lower surfaces of the rectangular beams being parallel to the side walls of the cabin 3 facing them. The two outer measuring beams 222 have the same height and width, and the two inner measuring beams 221 have the same height and width; the height of the outer measuring beams 222 is less than the height of the inner measuring beams 221, and the widths are equal.

[0044] A circular hole 231 for routing the hinge torque balance 2 is reserved on the balance element transition section 23 .

[0045] During the wind tunnel test, the aerodynamic load acting on the hatch 1 causes the combined element 22 of the hinge moment balance 2 to produce corresponding deformation through the model connection ends 25 at both ends of the balance. Strain gauges are respectively attached to the upper and lower surfaces of the four-column rectangular beam to form a Wheatstone bridge. After the four voltage increment signals are processed by computer through different combinations, the axial force component, hinge moment component and rolling moment component of the aerodynamic load acting on the hatch 1 are accurately measured. The hinge moment is measured by the torsional deformation of the column beam, and the rolling moment and axial force are measured by the bending deformation of the column beam.

[0046] Compared with the traditional sheet balance, the sheet balance based on the column beam is much less sensitive to the connection state, has high measurement accuracy, and is more suitable for wind tunnel force measurement tests. Preferably, the four front and rear corners of the four pairs of symmetrically arranged measuring beams are all chamfered, that is, the two side faces of each measuring beam and the end faces of the fixed connection end 21 and the transition section 23 of the balance element are chamfered to reduce the stress concentration of the measuring beam under the aerodynamic force of the cabin door.

[0047] The normal force element 24 includes an "I"-shaped measuring beam 241 and a support beam 242. The "I"-shaped measuring beam 241 and the support beam 242 are both connected between the balance element transition section 23 and the model connection end 25. The support beam 242 is symmetrically arranged on both sides of the middle "I"-shaped measuring beam 241. The support beam 24 is a rectangular parallelepiped structure formed by a plurality of spring sheets arranged in parallel and spaced apart (here, 5 are preferred according to the balance structure characteristics and load size), and the arrangement direction of the plurality of spring sheets in each support beam 242 is parallel to the thickness direction of the "I"-shaped measuring beam (241), the thickness direction of the "I"-shaped measuring beam (241) is perpendicular to the surface of the cabin (3) facing it, and the width of the two end parts of the "I"-shaped measuring beam is greater than the width of the middle structure. According to the principle of deformation coordination and consistency, most of the normal force load is borne by the "I"-shaped measuring beam 241.

[0048] Preferably, there is an arc-shaped flexible hinge 1 232 connected to the support beam 242 on the outer side of the transition section 23 of the balance element; and there is an arc-shaped flexible hinge 252 connected to the support beam 242 on the outer side of the model connection end 25. The arc-shaped flexible hinge 1 232 includes a first cylindrical groove and a first rectangular groove opened on the surface of the transition section 23 of the balance element, the first rectangular groove is located between two adjacent support beams 242 and has a width equal to the distance between the two support beams 242, the length of the first rectangular groove along the length direction of the support beam 242 is greater than twice the thickness of the support beam 242, and the first cylindrical groove is arranged at one end of the first rectangular groove; the arc-shaped flexible hinge 252 includes a second cylindrical groove and a second rectangular groove opened on the surface of the model connection end 25, the second rectangular groove is located between two adjacent support beams 242 and has a width equal to the distance between the two support beams 242, the length of the second rectangular groove along the length direction of the support beam 242 is greater than twice the thickness of the support beam 242, and the second cylindrical groove is arranged at one end of the first rectangular groove. This flexible hinge has the characteristics of high sensitivity, good mechanical decomposition of force, and small interference to the balance. When the hinge torque balance 2 is subjected to aerodynamic load, since the stiffness of the support beam 242 in the direction of the axial force, hinge moment and rolling moment is much greater than that of the "I"-shaped measuring beam 241, the support beam 242 shares most of the load, and the "I"-shaped measuring beam 241 hardly deforms, which can greatly reduce the interference of the axial force, hinge moment and rolling moment on the normal force measurement.

[0049] During the wind tunnel test, the aerodynamic load acting on the hatch 1 causes the normal force element 24 of the hinge moment balance 2 to produce corresponding deformation through the model connection ends 25 at both ends of the balance. Strain gauges are respectively attached to the upper and lower surfaces of both ends of the "I"-shaped measuring beam (241). A Wheatstone bridge is formed. After the voltage increment signals on the front and rear symmetrical measuring beams 241 are superimposed and processed by a computer, the normal force component acting on the hatch 1 is accurately measured. The normal force is measured by the bending deformation of the measuring beam 241.

[0050] Preferably, the four front and rear corners of the symmetrically arranged "I"-shaped measuring beam 241 and supporting beam 242 are all rounded to reduce stress concentration of the beams.

[0051] The normal force element 24 adopts a symmetrical structural design, which reduces the difficulty of mechanical processing, and also reduces the interference of the axial force, hinge torque and rolling torque on the normal force component, thereby improving the measurement accuracy of the normal force.

[0052] The fixed connection end 21 is designed with a rectifier 5 at both ends, and the other end of the rectifier 5 extends to the door connection end 25, so that the strain gauge is covered by the rectifier 5, so that the strain gauge is not exposed to the airflow, preventing the test wind speed from damaging the balance element or generating a large temperature drift during the test, and does not collide with the door connection end 25. The rectifier 5 is fixedly connected to the fixed connection end 21 of the hinge torque balance 2 by screws.

[0053] During the wind tunnel test, the angle of the door 1 can be changed by changing the angle blocks of the connecting rods of the door 1. There is no need to replace the hinge moment balance, which greatly saves the test cost.

[0054] Since the cabin 3 connects two doors 1, the above embodiment introduces the structure of the door hinge torque measuring device between a door 1 and the cabin 3. During the wind tunnel test, the door hinge torque measuring device on the other side adopts a similar structure to the door hinge torque measuring device on this side; when measuring the hinge torque of the 0° door, the 0° door shape is about 1mm smaller than the non-0° door shape, and there is no second rectangular groove 12 in the middle, so as to avoid the 0° door colliding with the cabin and causing the hinge torque balance to fail.

[0055] The present invention provides a feasible low-speed wind tunnel test technical solution for measuring the hinge torque of a hatch door. The overall structural rigidity of the present invention is good, and the balance elements are symmetrically arranged, so that the relative position of the hatch door and the cabin after loading is guaranteed, and the measurement accuracy of the experimental data is high and more real and reliable. The hinge torque balance does not need to be replaced when the hatch door angle is changed, which greatly saves the test cost.

[0056] The contents not described in detail in this application specification belong to the common knowledge of those skilled in the art.

[0057] The present application is described in detail above in conjunction with specific implementation methods and exemplary examples, but these descriptions cannot be understood as limiting the present application. Those skilled in the art understand that, without departing from the spirit and scope of the present application, a variety of equivalent replacements, modifications or improvements can be made to the technical solution of the present application and its implementation methods, all of which fall within the scope of the present application. The scope of protection of the present application shall be subject to the attached claims.

Claims

1. A door hinge torque measuring device, characterized in that: It comprises a cabin door (1), a hinge moment balance (2), a cabin (3), a cabin door front connecting rod (6) and a cabin door rear connecting rod (8); The hinge moment balance (2) comprises a fixed connection end (21), both ends of which are sequentially connected to a combination element (22), a balance element transition section (23), a normal force element (24) and a model connection end (25); The fixed connection end (21) is fixedly connected to the cabin (3); the cabin door (1) is connected to a cabin door front connecting rod (6) and a cabin door rear connecting rod (8); and the other ends of the cabin door front connecting rod (6) and the cabin door rear connecting rod (8) are respectively fixedly connected to a model connection end (25); A plurality of strain gauges are attached to the combined element (22) and the normal force element (24).

2. A door hinge torque measuring device according to claim 1, characterized in that: The door (1) is provided with a first rectangular groove (11) and a third rectangular groove (13) which are not connected, and one end of the door front connecting rod (6) and the door rear connecting rod (8) connected to the door (1) is provided with a rectangular protruding connection end, and the first rectangular groove (11) and the third rectangular groove (13) are respectively transitionally matched with the rectangular protruding connection ends of the door front connecting rod (6) and the door rear connecting rod (8).

3. A door hinge torque measuring device according to claim 2, characterized in that: The door (1) is also connected to a door middle connecting rod (7), a second rectangular groove (12) is provided on the door (1), one end of the door middle connecting rod (7) is connected to the second rectangular groove (12), and the other end of the door middle connecting rod (7) is suspended above the hinge moment balance (2), with a minimum spacing of about 1 mm; When measuring the hinge moment applied to the 0° cabin door, the cabin door (1) has no second rectangular groove (12) and is not connected to the cabin door middle connecting rod (7).

4. A door hinge torque measuring device according to claim 1, characterized in that: The cabin (3) is connected to a cabin bottom cover (4) by means of screws, and a circular hole (31) for routing a hinge moment balance (2) is left at the lower rear side of the cabin (3).

5. The door hinge torque measuring device according to claim 1, characterized in that: There is a gap between the balance element transition section (23) and the model connection end (25) and the cabin (3); a straight circular flexible hinge (251) is provided on the side of the model connection end (25) close to the normal force element (24), and the straight circular flexible hinge (251) is composed of two semi-cylindrical grooves opened on the upper and lower surfaces of the model connection end (25) and symmetrically distributed, and the two semi-cylindrical grooves are along the direction perpendicular to the normal force element (24); the minimum distance from the screw holes (211) at both ends of the balance fixed connection end (21) to the combined element (22) is ≥10mm.

6. A door hinge torque measuring device according to claim 1, characterized in that: The combined element (22) comprises a plurality of measuring beams connected between the fixed connection end (21) and the transition section (23) of the balance element, the measuring beams being rectangular beams having a mutually parallel upper surface and a mutually parallel lower surface, and two mutually parallel side surfaces, the upper surface and the lower surface of the rectangular beam being parallel to the surface of the side wall of the cabin (3) facing the rectangular beam, and a strain gauge being attached to the upper surface and the lower surface of each rectangular beam; A circular hole (231) for routing the hinge moment balance (2) is reserved on the balance element transition section (23).

7. A door hinge torque measuring device according to claim 6, characterized in that: Eight measuring beams are provided, and each end of the fixed connection end (21) is connected to four measuring beams; the four measuring beams are arranged in sequence, the two outer measuring beams are outer measuring beams (222), and the two inner measuring beams are inner measuring beams (221); the two outer measuring beams (222) have the same height and width, and the two inner measuring beams (221) have the same height and width; the height of the outer measuring beam (222) is less than the height of the inner measuring beam (221), and the width of the outer measuring beam (222) is equal to that of the inner measuring beam (221).

8. A door hinge torque measuring device according to claim 6, characterized in that: The normal force element (24) comprises an "I"-shaped measuring beam (241) and a support beam (242), the "I"-shaped measuring beam (241) and the support beam (242) are both connected between the balance element transition section (23) and the model connection end (25), the support beam (242) is symmetrically arranged on both sides of the middle "I"-shaped measuring beam (241), the support beam (242) is a rectangular parallelepiped structure formed by a plurality of spring sheets arranged in parallel and at intervals, and the arrangement direction of the plurality of spring sheets in each support beam (242) is parallel to the thickness direction of the "I"-shaped measuring beam (241), and the thickness direction of the "I"-shaped measuring beam (241) is perpendicular to the surface of the cabin (3) facing it; The width of the two end portions of the "I"-shaped measuring beam is greater than the width of the middle structure, and strain gauges are respectively attached to the surfaces of the two end portions of the "I"-shaped measuring beam facing the support beam (242); an arc-shaped flexible hinge (232) is provided at the end portion of the balance element transition section (23) connected to the support beam (242); the arc-shaped flexible hinge (232) comprises a first cylindrical groove and a first rectangular groove provided on the surface of the balance element transition section (23); the first rectangular groove is located between two adjacent support beams (242) and has a width equal to the distance between the two support beams (242); the length of the first rectangular groove along the length direction of the support beam (242) is greater than The first cylindrical groove is twice the thickness of the support beam (242), and the first rectangular groove is arranged at one end of the first rectangular groove; the end of the model connection end (25) connected to the support beam (242) is provided with an arc-shaped flexible hinge 2 (252), and the arc-shaped flexible hinge 2 (252) includes a second cylindrical groove and a second rectangular groove provided on the surface of the model connection end (25), the second rectangular groove is located between two adjacent support beams (242) and the width is equal to the distance between the two support beams (242), the length of the second rectangular groove along the length direction of the support beam (242) is greater than twice the thickness of the support beam (242), and the second cylindrical groove is arranged at one end of the first rectangular groove.

9. A door hinge torque measuring device according to claim 6, characterized in that: The side surface of the measuring beam and the end surface of the fixed connection end (21) and the transition section (23) of the balance element are chamfered; The arrangement direction of the "I"-shaped measuring beam and the supporting beam is the width direction of the "I"-shaped measuring beam and the supporting beam, and the two sides of the "I"-shaped measuring beam in the width direction and the end faces of the fixed connection end (21) and the balance element transition section (23) are chamfered.

10. The door hinge torque measuring device according to claim 1, characterized in that: Both ends of the fixed connection end (21) are respectively designed with a rectifier piece (5) on one side close to the cabin (3) and on the other side away from the cabin (3), and the other end of the rectifier piece (5) extends to the model connection end (25).

Images