CN115356195A

CN115356195A - Loading device for small part static strength test and use method and application thereof

Info

Publication number: CN115356195A
Application number: CN202210857150.9A
Authority: CN
Inventors: 许飞; 吴世芳; 张喜娟; 董先莹; 曾瑾; 陈锴; 王岑
Original assignee: Chengdu Aircraft Industrial Group Co Ltd
Current assignee: Chengdu Aircraft Industrial Group Co Ltd
Priority date: 2022-07-20
Filing date: 2022-07-20
Publication date: 2022-11-18

Abstract

The invention provides a loading device for a small part static strength test, and a use method and application thereof, and the loading device mainly comprises a top plate, a bottom part, a supporting rod, a movable plate and a power mechanism, wherein the movable plate is provided with a first through hole; one end of the supporting rod is fixedly connected with the bottom plate; the other end of the supporting rod penetrates through the first through hole of the movable plate and is fixedly connected with the top plate; a strain measuring element is attached to the supporting rod; one end of the power mechanism is connected with the top plate; the other end of the power mechanism is fixedly connected with the movable plate. This application combines together power unit and load test mechanism, greatly reduced the complexity of structure, provide small, the high test device of portability, simultaneously, the mechanical type structure need not extra motor drive, through the cooperation with the measuring element that meets an emergency on movable plate, bracing piece and the bracing piece, greatly reduced equipment service condition, applicable in simple and easy outfield environmental test, the accuracy is high, facilitate promotion.

Description

Loading device for small part static strength test and use method and application thereof

Technical Field

The invention relates to the technical field of static strength testing devices, in particular to a loading device for a small part static strength test and a using method and application thereof.

Background

The aircraft structure static strength test is a ground test for verifying whether the aircraft structure static strength meets design requirements, is mainly used for identifying the design static strength of the aircraft structure and provides necessary data and information for verifying the strength and rigidity calculation method and the rationality of the structure design and manufacturing process, thereby providing guarantee for the flight safety and the structure safety of the aircraft. In the static strength test of the aircraft structure, a certain magnitude of static load is generally applied to the aircraft structure through a loading device, and then the bearing capacity and the safety margin of the aircraft structure are tested by measuring the deformation, the strain state and the like of the structure.

The existing static strength test device for small parts of an airplane generally comprises a loading device and a load display device, a motor is generally adopted for driving and a test host is arranged, the size is large, the weight is heavy, and the whole set of test device is not easy to frequently move, so that the static strength test device is not suitable for static strength test in an outfield under a simple condition.

Disclosure of Invention

The invention aims to: aiming at the problems that the loading device for the small part static strength test in the prior art is complex in structure, large and heavy in size, poor in portability, high in requirement on equipment use conditions, not applicable to a simple external field environment and the like, the loading device for the small part static strength test, and the use method and application thereof are provided. The application provides a loading test device, simple structure, the portability is strong, need not motor drive, and easy operation is applicable to the outfield operation of simple and easy condition.

In order to achieve the purpose, the invention adopts the technical scheme that:

a loading device for a small part static strength test comprises a top plate, a bottom plate, a supporting rod, a movable plate and a power mechanism; the movable plate is provided with a first through hole; one end of the supporting rod is fixedly connected with the bottom plate; the other end of the supporting rod penetrates through the first through hole of the movable plate and is fixedly connected with the top plate; the top plate, the movable plate and the bottom plate are oppositely arranged; a strain measuring element is attached to the supporting rod; one end of the power mechanism is connected with the top plate; the other end of the power mechanism is fixedly connected with the movable plate; the power mechanism is a connecting rod mechanism, a lead screw nut mechanism, a gear rack mechanism, a gear transmission mechanism or a scissor fork mechanism; the movable plate and the bottom plate are used for placing a part to be tested; the power mechanism is adjusted to drive the movable plate to move towards or away from the bottom plate so as to apply pressure or release pressure to the part to be tested.

The invention provides a loading device for a small part static strength test, which mainly comprises a top plate, a bottom part, a supporting rod, a movable plate and a power mechanism, wherein the movable plate is provided with a first through hole; one end of the supporting rod is fixedly connected with the bottom plate; the other end of the supporting rod penetrates through the first through hole of the movable plate and is fixedly connected with the top plate; the top plate, the movable plate and the bottom plate are arranged oppositely; a strain measuring element is attached to the supporting rod; one end of the power mechanism is connected with the top plate; the other end of the power mechanism is fixedly connected with the movable plate. This application combines together power unit and load test mechanism, greatly reduced the complexity of structure, it is small to provide out, the high test device of portability, simultaneously, power unit adopts link mechanism, lead screw nut mechanism, rack and pinion mechanism, gear drive or cuts fork mechanism, the mechanical type structure need not extra motor drive, through with the cooperation of the measuring element that meets an emergency on movable plate, bracing piece and the bracing piece, greatly reduced equipment service condition, it is applicable in simple and easy outfield environmental test. When using, arrange the part to be measured in on the bottom plate, be in between bottom plate and the movable plate, can drive the movable plate and remove and then exert pressure or the pressure release for the part to be measured to being close to or keeping away from the bottom direction through adjusting power unit, carry out the relation of load and strain value to the device in advance, can know the strain value that the design load corresponds through calculating, when exerting pressure to the part to be measured and reaching the design strain value, can observe the influence of design load to the widget, the accuracy is high, application method is simple, and the operation of being convenient for.

Furthermore, the top plate and the bottom plate are arranged in parallel relatively, and the support rods are respectively perpendicular to the top plate and the bottom plate.

The movable plate is provided with a plurality of first through holes, each first through hole corresponds to one support rod, and at least one support rod is attached with a strain measuring element.

Further, a linear bearing is arranged in the first through hole. The linear bearing can reduce the friction force in the moving process of the movable plate, so that the movable plate is supported to move stably.

Further, the power mechanism comprises a top mounting base, a bottom mounting base, a first side mounting base and a second side mounting base; the device also comprises a first arm, a second arm, a third arm and a fourth arm; and a transverse strut; the top mounting base is fixedly connected to the top plate; the bottom mounting base is fixedly connected to the bottom plate; external threads are respectively arranged at two ends of the transverse supporting rod, and the rotating directions of the external threads at the two ends of the transverse supporting rod are opposite; a second through hole is formed in the middle of the first side mounting base, an inner thread is formed in the inner wall of the second through hole, and the inner thread of the second through hole is matched with the outer thread at one end of the transverse supporting rod; a third through hole is formed in the middle of the second side mounting base, an inner thread is formed in the inner wall of the third through hole, and the inner thread of the third through hole is matched with the outer thread at the other end of the transverse supporting rod; one end of the first arm is hinged with the top mounting base, and the other end of the first arm is hinged with the first side mounting base; one end of the second arm is hinged with the top mounting base, and the other end of the second arm is hinged with the second side mounting base; one end of the third arm is hinged with the bottom mounting base, and the other end of the third arm is hinged with the first side mounting base; one end of the fourth arm is hinged with the bottom mounting base, and the other end of the fourth arm is hinged with the second side mounting base; the first arm and the third arm are arranged on two sides of the transverse supporting rod; the second arm and the fourth arm are arranged on two sides of the transverse supporting rod; the first arm and the third arm can be driven to be close to or far from the second arm and the fourth arm through a threaded structure by rotating the transverse supporting rod, and the second arm and the fourth arm are correspondingly close to or far from the first arm and the third arm at the same time, so that the movable plate can be driven to move towards the direction close to or far from the bottom plate to apply pressure or release pressure to the part to be tested.

Further, the first arm, the second arm, the third arm, the fourth arm, the second side mounting base, the first side mounting base, and the cross brace move in the same plane or in opposite parallel planes.

Further, an included angle formed between the first arm and the third arm is not less than 10 degrees; the included angle formed between the second arm and the fourth arm is not less than 10 degrees.

Furthermore, a boss is arranged in the middle of the transverse supporting rod. The boss is used for being clamped by a tool to rotate the transverse supporting rod.

Further, the external threads on the transverse supporting rod are rectangular threads. The rectangular thread design can achieve smooth application and uniform transfer of load.

Furthermore, the supporting rod is in threaded connection with the top plate. The levelness of the top plate can be adjusted when the supporting rods are convenient to detach.

Furthermore, the supporting rod is in threaded connection with the bottom plate.

Furthermore, the power mechanism comprises a vertical support rod, an external thread is arranged at one end of the vertical support rod, a fourth through hole is arranged in the middle of the top plate, an internal thread is arranged on the inner wall of the fourth through hole, and the internal thread of the fourth through hole is matched with the external thread of the vertical support rod; one end of the vertical support rod with the external thread penetrates through the fourth through hole, the other end of the vertical transverse support rod is fixedly connected with the movable plate, a nut is arranged on the vertical transverse support rod, and the nut is rotated to adjust the relative distance between the top plate and the movable plate, so that the movable plate can be driven to move towards the direction close to or far away from the bottom plate, and pressure is applied to or released from the component to be tested.

Further, the strain measuring element is disposed at a position close to the base plate.

Further, the strain measuring element comprises T-shaped strain gauges which are oppositely arranged along the circumferential direction of the supporting rod, and the T-shaped strain gauges are used for forming a Wheatstone bridge. By measuring the strain by means of a wheatstone bridge, the measurement accuracy can be improved.

Further, the top plate, the bottom plate and the movable plate are structural members made of hard aluminum materials. Therefore, the whole weight of the test device can be reduced, and the test device is convenient to carry.

The invention also aims to provide a using method of the loading device for the static strength test of the small parts.

The use method of the loading device for the static strength test of the small parts comprises the following steps:

step 1, placing a mechanical sensor on the bottom plate, and loading the movable plate for a plurality of times by using the power mechanism to obtain a curve relation between a stress value of the mechanical sensor and a strain value displayed by the strain measurement element;

step 2, calculating a design strain value corresponding to the design loading value of the force according to the curve relation obtained in the step 1;

and 3, placing the component to be tested on the bottom plate, loading the movable plate to a designed strain value by using the power mechanism, and observing the state of the component to be tested.

The invention provides a use method of a loading device for a small part static strength test, which is mainly characterized in that a part to be tested is arranged on a bottom plate and is positioned between the bottom plate and a movable plate, the movable plate can be driven to move towards the direction close to or away from the bottom by adjusting a power mechanism so as to apply pressure or release pressure to the part to be tested, a strain value corresponding to a design load is calculated by calibrating the relation between the load and the strain value of the device in advance, when the part to be tested is applied with pressure and reaches the design strain value, the influence of the design load on the small part can be observed, the precision is high, the use method is simple, and the operation is convenient.

Furthermore, when the loading test device only comprises one supporting rod, the strain measuring element is attached to the supporting rod; in the step 1, a mechanical sensor is arranged on the bottom plate, the power mechanism is used for loading and applying pressure to the movable plate for a plurality of times, a group of data of stress values and strain values can be obtained by applying pressure each time, and a plurality of groups of data of stress values and strain values are obtained after loading different pressure values for a plurality of times, so that the curve relationship of the stress values and the strain values is obtained, namely the curve relationship between the stress values of the mechanical sensor and the strain values displayed by the strain measuring element;

when the loading test device comprises n (n is a natural number which is more than or equal to 2) support rods, wherein the strain measurement elements are attached to m (m is a natural number, m is more than or equal to 2 and less than or equal to n) support rods, in the step 1, a mechanical sensor is arranged on the bottom plate, the movable plate is loaded and pressurized for a plurality of times by using the power mechanism, a stress value and m strain values can be obtained by pressurizing each time, the m strain values are averaged to obtain a group of data of the stress value and the average strain value, and a plurality of groups of data of the stress value and the average strain value are obtained after different pressure values are loaded for a plurality of times, so that the curve relationship of the stress value and the average strain value is obtained, and the curve relationship of the stress value of the mechanical sensor and the strain value displayed by the strain measurement elements is obtained.

Further, when the loading test device comprises n support rods, wherein the strain measuring elements are attached to m support rods, the design strain value obtained in the step 2 is an average value of the strain values displayed by the m strain measuring elements.

The invention also aims to provide application of the loading device for the static strength test of the small parts.

The application of the loading device for the static strength test of the small parts in the loading test of the airplane structural part is disclosed.

The static strength test of aircraft widget structure can meet the outfield environment of simple and easy condition often, utilizes the test device equipment service condition of this application to require lowly, and the portability is strong, can solve the loading of the static strength test of various types of aircraft widget and the load of aircraft structure dress parts under the special environment and mark to guarantee the flight safety of aircraft.

In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:

1. the invention provides a loading device for a small part static strength test, which mainly comprises a top plate, a bottom part, a supporting rod, a movable plate and a power mechanism, wherein the movable plate is provided with a first through hole; one end of the supporting rod is fixedly connected with the bottom plate; the other end of the supporting rod penetrates through the first through hole of the movable plate and is fixedly connected with the top plate; the top plate, the movable plate and the bottom plate are oppositely arranged; a strain measuring element is attached to the supporting rod; one end of the power mechanism is connected with the top plate; the other end of the power mechanism is fixedly connected with the movable plate. This application combines power unit and load test mechanism into an organic whole, greatly reduced the complexity of structure, provide small, the test device that portability is high, and simultaneously, power unit adopts link mechanism, lead screw nut mechanism, rack and pinion mechanism, gear drive or cuts fork mechanism, and the mechanical type structure need not extra motor drive, through the cooperation with the measuring element that meets an emergency on movable plate, bracing piece and the bracing piece, greatly reduced equipment service conditions, applicable in simple and easy outfield environmental test.

2. The invention provides a use method of a loading device for a small part static strength test, which is mainly characterized in that a part to be tested is arranged on a bottom plate and is positioned between the bottom plate and a movable plate, the movable plate can be driven to move towards the direction close to or away from the bottom by adjusting a power mechanism so as to apply pressure or release pressure to the part to be tested, a strain value corresponding to a design load is calculated by calibrating the relation between the load and the strain value of the device in advance, when the part to be tested is applied with pressure and reaches the design strain value, the influence of the design load on the small part can be observed, the accuracy is high, the use method is simple, and the operation is convenient.

3. The static strength test of aircraft widget structure can meet the outfield environment of simple and easy condition often, utilizes the test device equipment service condition of this application to require lowly, and the portability is strong, and the accuracy is high, can solve the loading of the static strength test of various types of aircraft widget and the load of aircraft structure equipment under the special environment and mark to guarantee the flight safety of aircraft.

Drawings

FIG. 1 is a schematic diagram of the configuration of the loading test apparatus of the small parts of example 1.

Fig. 2 is a schematic structural diagram of the first side mounting base in fig. 1.

Fig. 3 is a schematic structural view of the first arm in fig. 1.

Fig. 4 is a schematic structural view of the joint of the top plate and the support rod.

Fig. 5 is a schematic structural view of the joint of the top plate and the support rod.

Fig. 6 is a schematic structural view of the support rod.

FIG. 7 is a schematic diagram of the configuration of the load testing apparatus of the small parts of example 1.

FIG. 8 is a schematic diagram of a Wheatstone bridge.

FIG. 9 is a force analysis diagram in the case of loading according to example 1.

Reference numerals:

1-a top plate; 11-a fourth through hole; 2-a bottom plate; 3-supporting rods; 31-a strain measuring element; 171-a first fastener; 172-a second fastener; 141-a first section; 141 a-a first lightbar segment; 141 b-a first screw section; 142-a second section; 142 a-a second lightbar segment; 142 b-a second screw section; 143-shoulder; 18-a sleeve; 173-a third fastener; 4-a movable plate; 41-a first through hole; 5, a power mechanism; 51-a top mounting base; 52-bottom mounting base; 53-a first side mounting base; 1551-first body; 1552-a first ear; 1553-second ear; 1511-a second body; 1512-third ear; 1513-fourth ear; 1514-first sub-ear; 1515-second sub-ear; 158-bolts; 531-a second through hole; 54-a second side mounting base; 541-a third through hole; 55-a first arm; 56-a second arm; 57-third arm; 58-a fourth arm; 59-transverse supporting rod; 591-vertical stay bar; 5911-a nut; a component 6 to be tested.

Detailed Description

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

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example 1

As shown in fig. 1, embodiment 1 provides a loading device for a small component static strength test, which includes a top plate 1, a bottom plate 2, four support rods 3, a movable plate 4 and a power mechanism 5; the movable plate 4 is provided with four first through holes 41; one end of the supporting rod 3 is fixedly connected with the bottom plate 2; the other end of the support rod 3 passes through the first through hole 41 of the movable plate 4 and is fixedly connected with the top plate 1; the top plate 1, the movable plate 4 and the bottom plate 2 are arranged oppositely; a strain gauge 31 is attached to the support bar 3, and the strain gauge 31 is disposed near the bottom plate 2. The top plate 1 and the bottom plate 2 are arranged in parallel relatively, and the support rods 3 are respectively perpendicular to the top plate 1 and the bottom plate 2.

One end of the power mechanism 5 is connected with the top plate 1; the other end of the power mechanism 5 is fixedly connected with the movable plate 4; the power mechanism 5 is a connecting rod mechanism, a lead screw nut mechanism, a gear rack mechanism, a gear transmission mechanism or a scissor fork mechanism. A component to be tested is placed between the movable plate 4 and the bottom plate 2; the power mechanism 5 can be adjusted to drive the movable plate 4 to move towards or away from the bottom plate 2 so as to apply pressure or release pressure to the component to be tested.

As shown in fig. 1, the power mechanism provided in embodiment 1 is a scissors mechanism, and has a stable force form and motion path, and can provide a stable load for the tested piece. The power mechanism 5 comprises a top mounting base 51, a bottom mounting base 52, a first side mounting base 53 and a second side mounting base 54; further comprising a first arm 55, a second arm 56, a third arm 57 and a fourth arm 58; and a crossbar 59; the top mounting base 51 is fixedly connected to the top plate 1; the bottom mounting base 52 is fixedly connected to the bottom plate 2; external threads are respectively arranged at two ends of the transverse supporting rod 59, and the rotating directions of the external threads at the two ends of the transverse supporting rod 59 are opposite; a second through hole 531 is formed in the middle of the first side mounting base 53, an internal thread is formed in the inner wall of the second through hole 531, and the internal thread of the second through hole 531 is matched with the external thread at one end of the transverse supporting rod 59; a third through hole 541 is formed in the middle of the second side mounting base 54, an internal thread is formed in the inner wall of the third through hole 541, and the internal thread of the third through hole 541 is matched with the external thread at the other end of the cross brace 59.

One end of the first arm 55 is hinged with the top mounting base 51, and the other end of the first arm 55 is hinged with the first side mounting base 5; one end of the second arm 56 is hinged with the top mounting base 51, and the other end of the second arm 56 is hinged with the second side mounting base 54; one end of the third arm 57 is hinged to the bottom mounting base 5, and the other end of the third arm 57 is hinged to the first side mounting base 53; one end of the fourth arm 58 is hinged to the bottom mounting base 52, and the other end of the fourth arm 58 is hinged to the second side mounting base 54; the first arm 55 and the third arm 57 are disposed on both sides of the crossbar 59; the second arm 56 and the fourth arm 58 are disposed on both sides of the crossbar 59. Preferably, the first arm 55, the second arm 56, the third arm 57 and the fourth arm 58 have the same length and the same structure. Preferably, the first arm 55, the second arm 56, the third arm 57, the fourth arm 58, the second side mounting base 54, the first side mounting base 53 and the cross brace 59 move in the same plane, and the included angle formed between the first arm 55 and the third arm 57 is not less than 10 °; the angle formed between the second arm 56 and the fourth arm 5 is not less than 10 °.

By rotating the cross brace 59, the first arm 55 and the third arm 57 can be driven to simultaneously approach or separate from the second arm 56 and the fourth arm 58 through a threaded structure, and the second arm 56 and the fourth arm 58 can also be correspondingly driven to simultaneously approach or separate from the first arm 55 and the third arm 57, so that the movable plate 4 can be driven to move towards or away from the bottom plate 2, and pressure can be applied or released to a component to be tested.

The first arm 55, the second arm 56, the third arm 57 and the fourth arm 58 are hinged to the top mounting base 51, the bottom mounting base 52, the first side mounting base 53 and the second side mounting base 54 by bolts 158. Fig. 3 discloses the structure of the first arm 55, as fig. 2 shows the structure of the first side mounting base 53. As shown in fig. 2, the first side mounting base 53 includes a first body 1551 and first and

second ears

1552 and 1553 extending away from both ends of the first body 1551. The first body 1551 is provided with a second through hole 531. Through holes are formed in the first lug portion 1552 and the second lug portion 1553, the axis of each through hole in the first lug portion 1552 is parallel to the axis of each through hole in the second lug portion 1553, and the axes of the through holes are perpendicular to the axis of the second through hole 531. Preferably, a step may be formed between the first ear 1552 and the first body 1551, and a step may be formed between the second ear 1553 and the first body 1551. In this way, the thickness of the first and

second ears

1552 and 1553 in the direction of the axis of the through hole may be smaller than the thickness of the first body 1551 in the direction, and accordingly, the thickness of the working arm coupled to the first and

second ears

1552 and 1553 in the direction may be reduced, thereby reducing the overall weight of the structure. As shown in fig. 3, first arm 55 includes a second main body 1511 and third and

fourth ears

1512, 1513 extending away from both ends of second main body 1511. Through holes are formed in the third ear portion 1512 and the fourth ear portion 1513, axes of the through holes in the third ear portion 1512 are parallel to axes of the through holes in the fourth ear portion 1513, and in an assembled state, the through holes are perpendicular to the axes of the second through holes 531. Third ear portion 1512 includes first sub-ear 1514 and second sub-ear 1515 disposed opposite from each other, and first sub-ear 1514 and second sub-ear 1515 define a gap therebetween for receiving first ear portion 1552 and providing space for movement of first ear portion 1552. For example, the first sub-ear 1514 and the second sub-ear 1515 may be formed by providing a straight slot in the end of the first arm 55. Preferably, first ear 1552 is shaped to the shape of third ear 1512, and third ear 1512 is shaped to the shape of first ear 1552. That is, first ear portion 1552 can include first and second opposing sub-ears with a gap disposed therebetween for receiving third ear portion 1512 and providing space for third ear portion 1512. Preferably, first ear 1552 and third ear 1512 can both be shaped to the shape of first ear 1552 or both be shaped to the shape of third ear 1512. The first side mounting base 53 and the second side mounting base 54 may be of a double-ended single-lug cylindrical structure, or of a double-ended double-lug cylindrical structure. The first arm 55 may have a cylindrical structure with both ends being monaural or a cylindrical structure with both ends being binaural.

Wherein, as shown in fig. 1, the support rod 3 and the bottom plate 2 can be connected by screw threads. Exemplarily, be provided with the internal thread hole on the bottom plate 2, the one end that is connected with bottom plate 2 of bracing piece 3 is provided with the external screw thread, can realize dismantling between bracing piece 3 and the bottom plate 2 through the cooperation in external screw thread and internal thread hole and be connected. The internal thread hole arranged on the bottom plate 2 can be used for adjusting the levelness of the bottom plate 2 besides being used for being connected with the supporting rod 3. The support rod 3 and the top plate 1 can be connected through threads. Be provided with the internal thread hole on the roof 1, the one end that is connected with roof 1 of bracing piece 3 is provided with the external screw thread, can realize dismantling between bracing piece 3 and the roof 1 to be connected through the cooperation in external screw thread and internal thread hole. The internal thread hole arranged on the top plate 1 can be used for connecting with the supporting rod 3 and adjusting the levelness of the top plate 1.

Preferably, as shown in fig. 4, the top plate 1 may be provided with a light hole, and one end of the support rod 3 connected to the top plate 1 is provided with an external thread. The support rod 3 passes through the light hole on the top plate 1. Wherein the top plate 1 is provided with a first fastening member 171 and a second fastening member 172 at both sides in the length direction of the support bar 3, and the first fastening member 171 and the second fastening member 172 are threadedly coupled to the support bar 3. During the assembly process, the second fastening member 172 may be screwed to the supporting rod 3, the supporting rod 3 may be inserted through the unthreaded hole of the top plate 1, and the first fastening member 171 may be screwed to the supporting rod 3. As shown in fig. 5 and 6, the support rod 3 may include a first section 141 and a second section 142, the first section 141 being adjacent to the top plate 1, and the second section 142 being adjacent to the bottom plate 2. The diameter of first section 141 is smaller than the diameter of second section 142 such that shoulder 143 is formed between first section 141 and second section 142. The end face of the shoulder 143 faces the top plate 1 in the mounted state. The first section 141 includes a first polish rod segment 141a proximate the shoulder 143 and a first screw segment 141b, the first polish rod segment 141a being located at the end of the first section 141. The first screw section 141b is provided with a fourth external thread for screwing with the third fastener 173. The sleeve 18 is sleeved on the first section 141 and abuts against the shoulder 143. The sleeve 18 is sleeved on the first polish rod section 141a and abuts against the shoulder 143. First rod section 141b is located entirely within sleeve 18, with at least a portion of first rod section 141b passing through sleeve 18. The outer surface of the sleeve 18 is provided with a fifth external thread for screwing with the top plate 1. In an assembled state, the sleeve 18 is sleeved on the first screw section 141a, and the third fastening member 173 is threadedly connected to the first screw section 141b, such that two ends of the sleeve 18 abut against the shoulder 143 and the third fastening member 173, respectively. The roof 1 is provided with the screw through-hole, and the surface of sleeve 18 is provided with the fifth external screw thread, and this fifth external screw thread closes mutually with the screw through-hole on the roof 1 soon to realize being connected of bracing piece 3 and roof 1. The top plate 1 is connected with the support rod 3 through a sleeve and a fastener, so that reliable detachable fixed connection can be realized. In addition, the levelness of the top plate 1 can be adjusted by adjusting the rotary sleeve 18. When the levelness of roof 1 is adjusted, need not swivel support pole 3, just can not influence the levelness of bottom plate 2 yet, can the decoupling zero roof 1 and the levelness adjustment process of bottom plate 2.

As shown in fig. 6, the second section 142 may include a second rod section 142a and a second screw section 142b, the second rod section 142a being proximate the shoulder 143, the second screw section 142b being located at an end of the second section 142. The second polished rod segment 142a passes through the movable plate 4. The second screw section 142b is provided with a sixth external thread for threaded connection with the base plate 2. The movable plate 4 is provided with a through hole for the support rod 3 to pass through. The support rod 3 may serve as a guide for guiding the movable plate 4 to move along the length direction of the support rod 3.

The invention provides a loading device for a small part static strength test, which mainly comprises a top plate, a bottom part, a supporting rod, a movable plate and a power mechanism, wherein the movable plate is provided with a first through hole; one end of the supporting rod is fixedly connected with the bottom plate; the other end of the supporting rod penetrates through the first through hole of the movable plate and is fixedly connected with the top plate; the top plate, the movable plate and the bottom plate are arranged oppositely; a strain measuring element is attached to the supporting rod; one end of the power mechanism is connected with the top plate; the other end of the power mechanism is fixedly connected with the movable plate. This application combines together power unit and load test mechanism, greatly reduced the complexity of structure, it is small to provide out, the high test device of portability, simultaneously, power unit adopts link mechanism, lead screw nut mechanism, rack and pinion mechanism, gear drive or cuts fork mechanism, the mechanical type structure need not extra motor drive, through with the cooperation of the measuring element that meets an emergency on movable plate, bracing piece and the bracing piece, greatly reduced equipment service condition, it is applicable in simple and easy outfield environmental test.

Example 2

Example 2a loading test apparatus similar to that of example 1 was provided, except that example 2 used a lead screw-nut mechanism, as shown in fig. 7.

The power mechanism 5 comprises a vertical support rod 591, wherein an external thread is arranged at one end of the vertical support rod 591, a fourth through hole 11 is arranged in the middle of the top plate 1, an internal thread is arranged on the inner wall of the fourth through hole 11, and the internal thread of the fourth through hole 11 is matched with the external thread of the vertical support rod 591; one end of the vertical stay 591 with an external thread penetrates through the fourth through hole 11, the other end of the vertical cross stay 591 is fixedly connected with the movable plate 4, a nut 5911 is arranged on the vertical cross stay 591, and the relative distance between the top plate 1 and the movable plate 4 can be adjusted by rotating the nut 5911, so that the movable plate 4 can be driven to move towards or away from the bottom plate 2 to apply pressure or release pressure to the component to be tested.

Preferably, as shown in fig. 8, the strain measuring element 31 includes a resistance strain gauge. A resistance strain gauge is a sensing element that can convert a change in strain on a mechanical member into a change in resistance, and may be referred to simply as a strain gauge. In use, the resistance strain gauge can be fixed on the surface of the support rod 3, and the sensitive grid of the resistance strain gauge is deformed along with the deformation of the support rod 3 under stress, so that the resistance of the resistance strain gauge is changed along with the deformation. The resistance change of the strain gauge is proportional to the strain of the support rod 3, and the resistance change can be converted into voltage or current change through a certain measuring circuit, so that the strain of the support rod 3 can be obtained.

The strain and the resistance change satisfy the following relationship:

ε＝(ΔR/R)/GF (1)

wherein ε is strain; Δ R is the resistance change. GF is a characteristic parameter of the strain gauge, sensitivity, provided by the strain gauge manufacturer, and is typically 2.0.R is a resistance value measured at room temperature without mounting and without stress, and is provided by a strain gauge manufacturer. When the strain of the supporting rod 3 is smaller, the resistance change of the strain gauge is smaller, and in order to ensure the measurement accuracy, the resistance change can be measured through a Wheatstone bridge. As shown in fig. 8, the wheatstone bridge is a ring circuit formed by connecting resistors R1, R2, R3, and R4 in sequence, a dc power supply is connected to one diagonal of the ring as excitation, and a load is output between the other diagonal. R1, R2, R3 and R4 are called bridge arms of the bridge. When R1/R2= R3/R4, the output voltage U =0 of the bridge, the bridge is balanced. The change of the resistance value of any one bridge arm can cause the bridge circuit to be unbalanced, and the bridge circuit can have voltage output. Any one of the resistors in the wheatstone bridge may be provided as a strain gauge and fixed to the support rod 3. When the support rod 3 deforms, the strain gauge deforms accordingly, and the resistance of the strain gauge changes from Rx when the bridge is balanced to Rx +, at which time the value of a detection instrument (such as a voltage detection instrument or a current detection instrument) changes. The value detected by the detecting instrument and the relation between the current or the voltage can be detected, and then the strain value of the supporting rod 3 can be calculated according to the relation between the value and the solid deformation (the above formula (1)). Alternatively, in some embodiments, the detection instrument may perform the correlation calculations internally and then output the strain of the support rod 3 directly. The four resistors in the wheatstone bridge may each be provided as a strain gauge and fixed to the support rods 3. The following bridge configurations can be used depending on how the strain gage is formed into the bridge: full-bridge and half-bridge (i.e., half-bridge). For example, a half bridge requires two active strain gages to be glued to the support 3, and the strain value of the strut 3 can be measured by connecting the two strain gages into a measuring module. For another example, the full bridge requires four effective strain gauges to be adhered to the support 3, and the strain value of the support rod 3 can be measured by connecting the four strain gauges to the measurement module. Alternatively, the strain gauge element 31 may include two T-shaped strain gauges provided at opposite positions on the support bar 3. In other words, the strain gauge element 31 includes T-shaped strain gauges that are oppositely disposed in the circumferential direction of the support rod 3. The oppositely arranged T-shaped strain gauges are used for forming a Wheatstone bridge. Specifically, each T-shaped strain gauge has a horizontal plate and a vertical plate, and the two T-shaped strain gauges include 4 plates in total, and the 4 plates can form a full bridge for strain measurement of the support rod 3.

Example 3

For easy understanding, fig. 9 shows a force analysis diagram of the test device in the working state of the example 1. When the component 6 to be tested is mounted between the movable plate 4 and the bottom plate 2 and the power mechanism 5 applies a static load to the component 6 to be tested, each component in the test apparatus is in a balanced state. The device under test 6 receives a downward force F2 (i.e., a direction opposite to the direction Z shown in fig. 9) applied by the movable plate 4 and an upward force F1 (i.e., the direction Z shown in fig. 9) applied by the bottom plate 2. Since the component 6 to be measured is in a balanced state, F1= F2. The movable plate 4 receives an upward urging force applied by the workpiece 6, and the urging force is equal to the urging force applied to the workpiece 6 by the movable plate 4, and is also F2. The movable plate 4 is also subjected to a downward force F3 exerted by the power means 5. Since the movable plate 4 is in a balanced state, F2= F3. The actuating mechanism 5 is subjected to the same magnitude and opposite direction of forces applied by the movable plate 4 and the top plate 1. Therefore, the force applied to the movable plate 4 by the power mechanism 5 is equal in magnitude and opposite in direction to the force applied to the top plate 1 by the power mechanism 5. The top plate 1 is subjected to an upward force F3 applied by the power mechanism 5 and a downward force F4 applied by the support rod 3. Since the top plate 1 is in a balanced state, F3= F4. It should be understood that when the number of the support rods 3 is plural, the downward force F4 applied to the top plate 1 should be the sum of the forces respectively applied to the top plate 1 by the plural support rods 3. Taking the number of the support rods 3 as four as shown in fig. 1 as an example, if the forces applied to the top plate 1 by the four support rods 3 are F14, F24, F34, and F44, respectively, F4= F14+ F24+ F34+ F44. The base plate 2 receives a downward force applied by the device under test 6, which is equal to the force applied by the base plate 2 to the device under test 6, and is also F1. The base plate 2 is also subjected to an upward force F5 exerted by the support bar 3. Since the soleplate 2 is in a balanced state, F1= F5. It should be understood that when the number of the support rods 3 is plural, the upward acting force F5 applied to the base plate 2 should be the sum of the acting forces respectively applied to the base plate 2 by the plural support rods 3. Taking the number of the support rods 3 as 4 as shown in fig. 1 as an example, if the forces applied to the bottom plate 2 by the 4 support rods 14 are F15, F25, F35, and F45, respectively, F5= F15+ F25+ F35+ F45. For each support bar 3, it is subjected to equal and opposite forces exerted by the top plate 1 and the bottom plate 2. When the number of the support rods 3 is plural, taking one of the support rods 3 (hereinafter referred to as a first support rod for convenience of description) as an example, assuming that it receives an upward force F14 applied by the top plate 1 and a downward force F15 applied by the bottom plate 2, since the first support rod 3 is in a balanced state, F14= F15. Taking another support bar 3 (hereinafter referred to as a second support bar for convenience of description) as an example, assuming that it receives an upward force F24 applied by the top plate 1 and a downward force F25 applied by the bottom plate 2, since the second support bar 3 is in a balanced state, F24= F25. In summary, as can be seen from the internal force analysis of the loading device 100, F1= F2= F3= F4= F5= the sum of the loads applied to the support rods 3. In particular, when the forces applied to the top plate 1 by the respective support rods 3 are equally spaced from the geometric center (or centroid) of the top plate 1, or the forces applied to the bottom plate 2 by the respective support rods 3 are equally spaced from the geometric center (or centroid) of the bottom plate 2, the forces applied to the top plate 1 (or bottom plate 2) by the respective support rods 3 are equally spaced. Therefore, the load applied by the top plate 1 or the bottom plate 2 is uniformly distributed on the respective support rods 3. That is, the load applied to each support rod 3 is equal. Thus, F1= F2= F3= F4= F5= the number of struts subjected to the load of a single strut 3. Thus, by measuring the load of one or more support rods 3, the load of the component 6 to be measured can be calculated. In the embodiment of the present application, the load of the support bar 3 can be obtained by measuring the strain of the support bar 3. For example, the relationship between the strain and the load of the brace 3 can be calibrated in advance, and the strain measuring element 16 is used to measure the strain of the brace 3 during the application, so that the load of the brace 3 can be obtained according to the strain of the brace 3 and the relationship between the strain and the load of the brace 3.

Based on the above analysis, it can be understood that when one support bar 3 is included, the load of the part 6 to be measured is equal to the load of the one support bar 3. Thus, a strain gauge element 31 may be included. When a plurality of support bars 3 are included, the load of the component 6 to be measured may be equal to the sum of the loads of the respective support bars 3 or equal to the product of the load of a single support bar 3 and the number of support bars 3. In this case, the strain gauge 31 is provided in a different manner depending on the method of calculating the load of the workpiece 6. Optionally, in an embodiment, each support bar 3 of the plurality of support bars 3 is provided with a strain measuring element 31. I.e., a plurality of strain measuring elements 16 and a plurality of support rods 3, the plurality of strain measuring elements 16 corresponding one-to-one to the plurality of support rods 3. Thus, each strain measuring element 16 measures the strain of the corresponding support rod 3, and accordingly, the load of each support rod 3 can be obtained from the strain of each support rod 3. Therefore, the load of the member to be measured 6 can be equal to the sum of the loads of the plurality of support bars 3.

Example 3 provides a method of using the loading test apparatus provided in examples 1 and 2.

Step 1, placing a mechanical sensor on the bottom plate 2, and loading the mechanical sensor to the movable plate 4 by using the power mechanism 5 to obtain a curve relation between a stress value of the mechanical sensor and a strain value displayed by the strain measurement element 31;

and 3, placing the component to be tested on the bottom plate 2, loading the movable plate 4 to a designed strain value by using the power mechanism 5, and observing the state of the component to be tested.

When the loading test device only comprises one supporting rod 3, the strain measuring element 31 is attached to the supporting rod 3; in the step 1, the mechanical sensor is placed on the bottom plate 2, the power mechanism 5 is used for loading and applying pressure to the movable plate 4, a group of data of stress values and strain values can be obtained by applying pressure every time, and after different pressure values are loaded for multiple times, multiple groups of data of stress values and strain values are obtained, so that the curve relation of the stress values and the strain values of the mechanical sensor is obtained, namely the curve relation of the stress values of the mechanical sensor and the strain values displayed by the strain measurement element.

When the loading test device comprises n (n is a natural number which is more than or equal to 2) support rods 3, wherein m (m is a natural number, and m is more than or equal to 2 and less than or equal to n) support rods 3 are attached with the strain measuring elements 31, in the step 1, a mechanical sensor is arranged on the bottom plate 2, the power mechanism 5 is used for applying pressure to the movable plate 4, a stress value and m strain values can be obtained by applying pressure each time, the m strain values are averaged to obtain a group of stress value-average strain value data, and after different pressure values are applied for multiple times, multiple groups of stress value-average strain value data are obtained to obtain a curve relation of the stress value-average strain value, and a curve relation of the stress value of the mechanical sensor and the strain value displayed by the strain measuring elements.

While the invention has been described with reference to specific embodiments, the scope of the invention is not limited thereto, and those skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the invention. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A loading device for a small part static strength test is characterized by comprising a top plate (1), a bottom plate (2), a supporting rod (3), a movable plate (4) and a power mechanism (5);

the movable plate (4) is provided with a first through hole (41);

one end of the supporting rod (3) is fixedly connected with the bottom plate (2); the other end of the supporting rod (3) passes through a first through hole (41) of the movable plate (4) and is fixedly connected with the top plate (1); the top plate (1), the movable plate (4) and the bottom plate (2) are arranged oppositely; a strain measuring element (31) is attached to the support rod (3);

one end of the power mechanism (5) is connected with the top plate (1); the other end of the power mechanism (5) is fixedly connected with the movable plate (4); the power mechanism (5) is a connecting rod mechanism, a lead screw nut mechanism, a gear rack mechanism, a gear transmission mechanism or a scissor fork mechanism;

the part to be tested is placed between the movable plate (4) and the bottom plate (2); the power mechanism (5) can be adjusted to drive the movable plate (4) to move towards the direction close to or away from the bottom plate (2) so as to apply pressure or release pressure to the component to be tested.

2. The loading device for the static strength test of small parts according to claim 1, characterized in that the top plate (1) and the bottom plate (2) are arranged in parallel and the supporting rods (3) are respectively arranged perpendicular to the top plate (1) and the bottom plate (2).

3. The loading device for the widget static strength test according to claim 2, characterized by comprising at least two support rods (3), wherein the movable plate (4) is provided with the same number of first through holes (41) as the support rods (3), each support rod (3) corresponds to one first through hole (41), and at least one support rod (3) is attached with a strain measuring element (31).

4. The loading device for the static strength test of small parts according to claim 1, characterized in that said power mechanism (5) comprises a top mounting base (51), a bottom mounting base (52), a first side mounting base (53), a second side mounting base (54); further comprising a first arm (55), a second arm (56), a third arm (57) and a fourth arm (58); and a crossbar (59);

the top mounting base (51) is fixedly connected to the top plate (1); the bottom mounting base (52) is fixedly connected to the bottom plate (2);

external threads are respectively arranged at two ends of the transverse supporting rod (59), and the rotating directions of the external threads at the two ends of the transverse supporting rod (59) are opposite;

a second through hole (531) is formed in the middle of the first side mounting base (53), internal threads are formed in the inner wall of the second through hole (531), and the internal threads of the second through hole (531) are matched with the external threads at one end of the transverse supporting rod (59); a third through hole (541) is formed in the middle of the second side mounting base (54), an inner thread is formed in the inner wall of the third through hole (541), and the inner thread of the third through hole (541) is matched with the outer thread at the other end of the transverse stay bar (59);

one end of the first arm (55) is hinged with the top mounting base (51), and the other end of the first arm (55) is hinged with the first side mounting base (53); one end of the second arm (56) is hinged with the top mounting base (51), and the other end of the second arm (56) is hinged with the second side mounting base (54); one end of the third arm (57) is hinged with the bottom mounting base (52), and the other end of the third arm (57) is hinged with the first side mounting base (53); one end of the fourth arm (58) is hinged with the bottom mounting base (52), and the other end of the fourth arm (58) is hinged with the second side mounting base (54);

the first arm (55) and the third arm (57) are arranged on both sides of the cross brace (59); the second arm (56) and the fourth arm (58) are arranged on both sides of the cross brace (59);

the first arm (55) and the third arm (57) can be driven to simultaneously approach or separate from the second arm (56) and the fourth arm (58) through a thread structure by rotating the cross brace (59), and the second arm (56) and the fourth arm (58) can also be correspondingly driven to simultaneously approach or separate from the first arm (55) and the third arm (57), so that the movable plate (4) can be driven to move towards the direction approaching or separating from the bottom plate (2) to further apply pressure or release pressure to a component to be tested.

5. The loading device for widget static strength testing according to claim 4 characterized in that said first arm (55), said second arm (56), said third arm (57), said fourth arm (58), said second side mounting base (54), said first side mounting base (53), and said cross brace (59) move in the same plane or in relatively parallel planes; the angle formed between the first arm (55) and the third arm (57) is not less than 10 °; the angle formed between the second arm (56) and the fourth arm (58) is not less than 10 degrees.

6. The loading device for the small part static strength test according to claim 1, characterized in that the power mechanism (5) comprises a vertical support rod (591), one end of the vertical support rod (591) is provided with an external thread, the middle part of the top plate (1) is provided with a fourth through hole (11), the inner wall of the fourth through hole (11) is provided with an internal thread, and the internal thread of the fourth through hole (11) is matched with the external thread of the vertical support rod (591); one end of the vertical stay rod (591) with an external thread penetrates through the fourth through hole (11), the other end of the vertical stay rod (591) is fixedly connected with the movable plate (4), a nut (5911) is arranged on the vertical stay rod (591), and the relative distance between the top plate (1) and the movable plate (4) can be adjusted by rotating the nut (5911), so that the movable plate (4) can be driven to move towards the direction close to or far away from the bottom plate (2) to apply pressure or release pressure to the part to be tested.

7. Loading device for the static Strength test of small parts according to any of the claims 1 to 6, characterised in that said strain-measuring element (31) is placed in proximity to said base plate (2).

8. Use of a loading device for the static strength test of small parts according to any of claims 1 to 7, characterised in that it comprises the following steps:

step 1, placing a mechanical sensor on a bottom plate (2), and loading the movable plate (4) for a plurality of times by using the power mechanism (5) to obtain a curve relation between a stress value of the mechanical sensor and a strain value displayed by a strain measurement element (31);

and 3, placing the component to be tested on the bottom plate (2), loading the movable plate (4) to a designed strain value by using the power mechanism (5), and observing the state of the component to be tested.

9. The method for using the loading device for the static strength test of small parts according to claim 8, characterized in that,

when the loading test device only comprises one supporting rod (3), the strain measuring element (31) is attached to the supporting rod (3); in the step 1, a mechanical sensor is arranged on the bottom plate (2), the power mechanism (5) is used for loading and applying pressure to the movable plate (4) for a plurality of times, a group of data of stress values-strain values can be obtained by applying pressure each time, and a plurality of groups of data of stress values-strain values are obtained after loading different pressure values for a plurality of times, so that the curve relation of the stress values-strain values is obtained, namely the curve relation of the stress values of the mechanical sensor and the strain values displayed by the strain measuring element;

when the loading test device comprises n (n is a natural number which is more than or equal to 2) support rods (3), wherein m (m is a natural number, m is more than or equal to 2 and is less than or equal to n) support rods (3) are attached with the strain measuring elements (31), in the step 1, the mechanical sensor is arranged on the bottom plate (2), the power mechanism (5) is utilized to load and apply pressure to the movable plate (4) for a plurality of times, the stress value and m strain values can be obtained by applying pressure every time, the m strain values are averaged to obtain a group of stress value-average strain value data, and after different pressure values are loaded for a plurality of times, a plurality of groups of stress value-average strain value data are obtained, so that the curve relationship between the stress value and the average strain value is obtained, and the curve relationship between the stress value of the mechanical sensor and the strain value displayed by the strain measuring elements.

10. Use of a loading device for static strength testing of small parts according to any of claims 1-7 for loading test aircraft structural parts.