CN110608830A - Braking force system testing structure of disc-shaped braking type force measuring framework and manufacturing method thereof - Google Patents

Braking force system testing structure of disc-shaped braking type force measuring framework and manufacturing method thereof Download PDF

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Publication number
CN110608830A
CN110608830A CN201810619222.XA CN201810619222A CN110608830A CN 110608830 A CN110608830 A CN 110608830A CN 201810619222 A CN201810619222 A CN 201810619222A CN 110608830 A CN110608830 A CN 110608830A
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China
Prior art keywords
strain gauge
braking
suspension arm
framework
arm
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CN201810619222.XA
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Chinese (zh)
Inventor
王曦
陈羽
杨广雪
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Beijing Jiaotong University
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Beijing Jiaotong University
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Priority to CN201810619222.XA priority Critical patent/CN110608830A/en
Publication of CN110608830A publication Critical patent/CN110608830A/en
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01LMEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L5/00Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Force Measurement Appropriate To Specific Purposes (AREA)

Abstract

The invention provides a braking force system test structure of a disc-shaped braking force measurement framework and a manufacturing method thereof, wherein a high-resolution load identification point area is defined on a braking suspension arm of the disc-shaped braking force measurement framework, and then a plurality of strain gauges are pasted on each high-resolution load identification point area to form a plurality of groups of full-bridge circuit structures; the method comprises the following steps that static calibration is carried out on a framework structure attached with strain gauges on a multichannel loading force measurement framework calibration test bed, decoupling calculation is carried out on each full-bridge circuit structure one by one, and one or more groups of bridge structures with the highest mutual decoupling precision or one or more groups of bridge structures meeting the decoupling precision requirement are found; and finally, finishing the manufacture of the force measuring framework according to the finally determined bridge combination structure. By adopting the structure and the method provided by the invention, one or more full-bridge circuits are formed on one or more braking suspension arms of the force measuring framework, and the aim of testing the braking force of the bogie is fulfilled by testing the feedback signals of the full-bridge circuits.

Description

Braking force system testing structure of disc-shaped braking type force measuring framework and manufacturing method thereof
Technical Field
The invention relates to a structure for testing a braking force system of a disc brake type dynamometric framework of a railway vehicle.
Background
For disc brake type bogies which are widely used in railway vehicles, there is no test method in the prior art for this type of bogie disc brake powertrain.
Disclosure of Invention
The purpose of the invention is: the braking force system test structure of the disc-shaped braking force measuring frame and the manufacturing method thereof are provided.
In order to achieve the purpose, the invention adopts the technical scheme that:
a braking force system test structure of a disc-shaped braking type force measuring frame is provided, the disc-shaped braking type force measuring frame is provided with two side beams and two cross beams, and one or more braking suspension arms are connected to the cross beams, and the disc-shaped braking type force measuring frame is characterized in that high-separation load identification point areas are defined on the one or more braking suspension arms, and are respectively as follows:
a first region: the upper surface of the braking suspension arm is far away from one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
a second region: the braking suspension arm is far away from one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
a third region: the braking suspension arm is close to one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
a fourth region: the upper surface of the braking suspension arm is close to one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
adhering at least one strain gauge on each high-resolution load identification point area; weighing: the strain gauge on the first area is a first strain gauge, the strain gauge on the second area is a second strain gauge, the strain gauge on the third area is a third strain gauge, and the strain gauge on the fourth area is a fourth strain gauge; a first strain gauge, a second strain gauge, a third strain gauge and a fourth strain gauge on the same brake suspension arm form a full-bridge circuit structure;
in the full-bridge circuit structure, the first strain gauge and the second strain gauge form an adjacent arm, the third strain gauge and the fourth strain gauge form an adjacent arm, the first strain gauge and the fourth strain gauge form a paired arm, and the second strain gauge and the third strain gauge form a paired arm.
The braking force system test structure of the disk braking type force measuring frame is characterized in that: at least one group of standby full-bridge circuit structures is arranged on at least one braking suspension arm of the dynamometric framework.
The invention also provides a manufacturing method of the braking force system testing structure of the disc-shaped braking type force measuring framework, the disc-shaped braking type force measuring framework is provided with two side beams and two cross beams, and one or more braking suspension arms are connected on the cross beams, and the manufacturing method is characterized by comprising the following steps:
(1) high-resolution load identification point regions are defined on the one or more braking booms, and are respectively as follows:
a first region: the upper surface of the braking suspension arm is far away from one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
a second region: the braking suspension arm is far away from one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
a third region: the braking suspension arm is close to one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
a fourth region: the upper surface of the braking suspension arm is close to one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
(2) adhering at least one strain gauge on each high-resolution load identification point area; weighing: the strain gauge on the first area is a first strain gauge, the strain gauge on the second area is a second strain gauge, the strain gauge on the third area is a third strain gauge, and the strain gauge on the fourth area is a fourth strain gauge; a first strain gauge, a second strain gauge, a third strain gauge and a fourth strain gauge on the same brake suspension arm form a full-bridge circuit structure;
in the full-bridge circuit structure, a first strain gauge and a second strain gauge form an adjacent arm, a third strain gauge and a fourth strain gauge form an adjacent arm, the first strain gauge and the fourth strain gauge form a paired arm, and the second strain gauge and the third strain gauge form a paired arm;
(3) the method comprises the following steps that static calibration is carried out on a framework structure attached with strain gauges on a multichannel loading force measurement framework calibration test bed, decoupling calculation is carried out on each full-bridge circuit structure one by one, and one or more groups of bridge structures with the highest mutual decoupling precision or one or more groups of bridge structures meeting the decoupling precision requirement are found;
(4) and finishing the manufacture of the force measuring framework according to the finally determined bridge combination structure.
The manufacturing method of the braking force system testing structure of the disk-shaped braking force measuring frame comprises the following steps: in the step (4), at least one group of standby full-bridge circuit structures are arranged on at least one braking suspension arm of the force measuring frame.
According to the invention, aiming at the stress characteristic of a disk-shaped brake bogie frame, a strain gauge is adhered to the surface of any one or more brake suspension arms of the frame to form a full-bridge circuit, and one or more braking forces of the bogie are obtained through direct test.
According to the motion characteristics of the framework, the bogie force measuring framework is designed directly according to the testing requirements of the framework braking force system; according to the stress characteristic of the disc-shaped brake bogie, an independent full-bridge circuit is designed on a brake suspension arm of the framework, so that the overall braking force system of the framework has a larger response level on the basis of careful calculation, and meanwhile, the interference response generated by other force systems is far lower than the braking test response, so that the decoupling accuracy of each force system is ensured. The bogie force measuring framework ensures the test precision and enables the measured load and the structural strain to present a better quasi-static relation.
Drawings
FIG. 1 is a schematic top view of a disc brake truck dynamometric frame with a strain gage attached to a surface of one of the brake booms;
FIG. 1A is a bridge configuration diagram of a dynamometric frame braking force test configuration;
FIG. 2 and FIG. 3 are strain gage attachment areas of a dynamometric frame brake force test configuration.
Description of reference numerals: 1-a first strain gauge; 2-a second strain gage; 3-a third strain gauge; 4-a fourth strain gage; 71-braking the boom; 72-a cross beam; 73-side beam; 74-side beam; s1-range; s2-range; s3-range; s4-range; a-the frame transverse centerline; b-the longitudinal centerline of the framework.
Detailed Description
The manufacturing method of the bogie force measuring frame is described by combining the accompanying drawings as follows:
(1) a finite element model of the disk-shaped brake type force measuring framework is established by adopting a finite element method, a simulation load is applied to the framework structure, a strain bridge combination mode is designed on the framework aiming at the braking force system, and a high-resolution load identification point area of the force measuring framework is determined.
In the step (1), the specific process and step of searching the high-resolution load identification point region on the frame do not fall within the scope of the present invention, nor do they affect the use of the present invention by the public for load testing, and therefore, the present invention is not described in detail.
The invention can confirm that: a typical disk brake dynamometric frame, as shown in fig. 1, has two cross members 72 and two side members 73, 74, with one or more brake booms 71 attached to the cross members 72. High-resolution load identification point regions are defined on the one or more braking booms 71, respectively:
a first region: the upper surface of the braking boom 71 is located on the side away from the longitudinal center line b of the frame and between the junction of the cross beam 72 and the braking boom 71 to the outboard end of the braking boom 71 (as indicated by the range S1);
a second region: the braking boom 71 is located on the side away from the frame longitudinal centerline b and between the junction of the cross beam 72 and the braking boom 71 to the outboard end of the braking boom 71 (as shown in range S2);
a third region: the braking boom 71 is located on one side of the longitudinal center line b of the frame and between the junction of the cross beam 72 and the braking boom 71 to the outboard end of the braking boom 71 (as shown in range S3);
a fourth region: the upper surface of the braking boom 71 is located on the side of the frame longitudinal centerline b between the junction of the cross beam and the braking boom 71 to the outboard end of the braking boom 71 (as shown in range S4).
(2) Adhering a plurality of strain gauges to each high-resolution load identification point area; weighing: the strain gauge on the first area is a first strain gauge 1, the strain gauge on the second area is a second strain gauge 2, the strain gauge on the third area is a third strain gauge 3, and the strain gauge on the fourth area is a fourth strain gauge 4; since the number of the first strain gauge 1, the second strain gauge 2, the third strain gauge 3 and the fourth strain gauge 4 is plural, a group of full-bridge circuit structures can be formed by any one of the first strain gauge 1, any one of the second strain gauge 2, any one of the third strain gauge 3 and any one of the fourth strain gauge 4; as shown in fig. 1A, in each full-bridge circuit structure, a first strain gauge 1 and a second strain gauge 2 form an adjacent arm, a third strain gauge 3 and a fourth strain gauge 4 form an adjacent arm, the first strain gauge 1 and the fourth strain gauge 4 form a paired arm, and the second strain gauge 2 and the third strain gauge 3 form a paired arm;
(3) the framework structure adhered with the strain gauge is statically calibrated on a calibration test bed special for a multichannel loading force measurement framework, each full-bridge circuit structure is subjected to decoupling calculation one by one, and one or more groups of bridge structures with highest mutual decoupling precision or one or more groups of bridge structures meeting the decoupling precision requirement are found;
the decoupling accuracy refers to the response capability of the full-bridge circuit output to the tested force system, and the influence capability of other disturbance force systems (such as a vertical load force system) on the tested force system on the full-bridge circuit. The decoupling precision is high, which means that the full-bridge circuit has high response to the tested force system and is slightly influenced by the interference force system.
(4) Finishing the manufacture of the force measuring framework according to the finally determined bridge combination structure; namely, removing the redundant strain gauge, and if necessary, sticking the strain gauge again at the determined strain gauge sticking position; if necessary, at least one set of spare bridging structures is arranged on each braking boom 71 of the dynamometric framework.
Therefore, the invention provides the braking force system testing structure of the disk-shaped braking force measuring framework and the manufacturing method thereof, which not only ensure the testing precision, but also enable the tested load and the structural strain to present a better quasi-static relationship.

Claims (4)

1. A braking force system test structure of a disc-shaped braking type force measuring frame is provided, the disc-shaped braking type force measuring frame is provided with two side beams and two cross beams, and one or more braking suspension arms are connected to the cross beams, and the disc-shaped braking type force measuring frame is characterized in that high-separation load identification point areas are defined on the one or more braking suspension arms, and are respectively as follows:
a first region: the upper surface of the braking suspension arm is far away from one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
a second region: the braking suspension arm is far away from one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
a third region: the braking suspension arm is close to one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
a fourth region: the upper surface of the braking suspension arm is close to one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
adhering at least one strain gauge on each high-resolution load identification point area; weighing: the strain gauge on the first area is a first strain gauge, the strain gauge on the second area is a second strain gauge, the strain gauge on the third area is a third strain gauge, and the strain gauge on the fourth area is a fourth strain gauge; a first strain gauge, a second strain gauge, a third strain gauge and a fourth strain gauge on the same brake suspension arm form a full-bridge circuit structure;
in the full-bridge circuit structure, the first strain gauge and the second strain gauge form an adjacent arm, the third strain gauge and the fourth strain gauge form an adjacent arm, the first strain gauge and the fourth strain gauge form a paired arm, and the second strain gauge and the third strain gauge form a paired arm.
2. The structure for testing a braking force system of a disc brake dynamometer according to claim 1, wherein: at least one group of standby full-bridge circuit structures is arranged on at least one braking suspension arm of the dynamometric framework.
3. A manufacturing method of a braking force system test structure of a disc-shaped braking type force measuring framework is provided, the disc-shaped braking type force measuring framework is provided with two side beams and two cross beams, and one or more braking suspension arms are connected to the cross beams, and the manufacturing method is characterized by comprising the following steps:
(1) high-resolution load identification point regions are defined on the one or more braking booms, and are respectively as follows:
a first region: the upper surface of the braking suspension arm is far away from one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
a second region: the braking suspension arm is far away from one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
a third region: the braking suspension arm is close to one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
a fourth region: the upper surface of the braking suspension arm is close to one side of the longitudinal center line of the framework and is positioned between the joint of the cross beam and the braking suspension arm and the outer end of the braking suspension arm;
(2) adhering at least one strain gauge on each high-resolution load identification point area; weighing: the strain gauge on the first area is a first strain gauge, the strain gauge on the second area is a second strain gauge, the strain gauge on the third area is a third strain gauge, and the strain gauge on the fourth area is a fourth strain gauge; a first strain gauge, a second strain gauge, a third strain gauge and a fourth strain gauge on the same brake suspension arm form a full-bridge circuit structure;
in the full-bridge circuit structure, a first strain gauge and a second strain gauge form an adjacent arm, a third strain gauge and a fourth strain gauge form an adjacent arm, the first strain gauge and the fourth strain gauge form a paired arm, and the second strain gauge and the third strain gauge form a paired arm;
(3) the method comprises the following steps that static calibration is carried out on a framework structure attached with strain gauges on a multichannel loading force measurement framework calibration test bed, decoupling calculation is carried out on each full-bridge circuit structure one by one, and one or more groups of bridge structures with the highest mutual decoupling precision or one or more groups of bridge structures meeting the decoupling precision requirement are found;
(4) and finishing the manufacture of the force measuring framework according to the finally determined bridge combination structure.
4. The method for manufacturing a braking force system test structure of a disc brake type dynamometric frame as claimed in claim 3, wherein: in the step (4), at least one group of standby full-bridge circuit structures are arranged on at least one braking suspension arm of the force measuring frame.
CN201810619222.XA 2018-06-15 2018-06-15 Braking force system testing structure of disc-shaped braking type force measuring framework and manufacturing method thereof Pending CN110608830A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111811722A (en) * 2020-07-10 2020-10-23 北京交通大学 Motor vertical load testing structure and method for rib plate type motor suspension force measuring framework
CN111829713A (en) * 2020-07-10 2020-10-27 北京交通大学 Motor vertical force system testing structure of hanging seat type force measurement framework and manufacturing method thereof

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111811722A (en) * 2020-07-10 2020-10-23 北京交通大学 Motor vertical load testing structure and method for rib plate type motor suspension force measuring framework
CN111829713A (en) * 2020-07-10 2020-10-27 北京交通大学 Motor vertical force system testing structure of hanging seat type force measurement framework and manufacturing method thereof
CN111811722B (en) * 2020-07-10 2022-03-01 北京交通大学 Manufacturing method of motor vertical load testing structure of rib plate type motor suspension force-measuring framework

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