A fixture for testing the frictional work of an engine piston assembly
By using a simplified piston assembly friction work testing fixture, the problems of complexity and inaccurate simulation in traditional testing methods are solved, enabling efficient and accurate friction work testing and supporting engine performance optimization.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- JIANGLING MOTORS
- Filing Date
- 2025-06-23
- Publication Date
- 2026-06-30
AI Technical Summary
Traditional piston assembly friction work testing methods are complex in structure and cumbersome in operation, and cannot accurately simulate the actual working conditions of the piston assembly in the engine, resulting in inaccurate test results and affecting engine performance optimization.
A test fixture was designed, comprising an upper base, a lower base, an upper connecting rod bearing, a lower connecting rod bearing, and connecting bolts. The fixture has a simple structure, and its center of gravity is aligned with that of the piston assembly. It can accurately simulate the working conditions inside the engine and reflect frictional work through a reverse drag test.
It reduces testing costs and time, improves the accuracy of test results, provides a reliable basis for engine optimization design, ensures sealing performance, and avoids additional friction and wear.
Smart Images
Figure CN224435615U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of automotive testing technology, specifically to a testing fixture for the frictional work of an engine piston assembly. Background Technology
[0002] In engine development, the proportion of piston assembly friction work is a key indicator, directly affecting the engine's fuel economy, power output, and reliability. However, traditional methods for testing piston assembly friction work have many problems.
[0003] On the one hand, some testing fixtures have complex structures and are cumbersome to operate, which not only significantly increases testing costs and time, but also easily introduces human error during operation, thereby affecting the accuracy of test results.
[0004] On the other hand, some testing fixtures cannot accurately simulate the actual working conditions of the piston assembly within the engine, such as key parameters like reciprocating mass and center of gravity position. This results in significant deviations between the friction work data obtained from the tests and the actual situation. Such deviations prevent the test results from providing a reliable basis for the optimized design of the engine, thereby affecting the improvement of the overall engine performance.
[0005] To address the aforementioned issues, this invention provides a friction work testing fixture for piston assembly systems. The aim is to simplify the testing structure and accurately simulate actual operating conditions, thereby providing more accurate and reliable friction work test data for the optimized design of engines. Utility Model Content
[0006] To address the shortcomings of existing technologies, this utility model provides a testing fixture for the frictional work of an engine piston assembly, which solves the problems of traditional testing fixtures being complex in structure, unable to accurately simulate actual working conditions, and having poor versatility.
[0007] To achieve the above objectives, this utility model provides the following technical solution: a testing fixture for the frictional work of an engine piston assembly, comprising:
[0008] The fixture has an upper base and a lower base, both of which are semi-circular. A connecting bolt is provided between the upper base and the lower base, and the upper base and the lower base are symmetrically installed by the connecting bolt.
[0009] The upper connecting rod bearing and the lower connecting rod bearing are respectively fitted to the inner rings of the upper base and the lower base of the tooling, and the upper connecting rod bearing and the lower connecting rod bearing are symmetrically arranged;
[0010] The overall mass of the upper and lower bases of the tooling, the upper connecting rod bearing, the lower connecting rod bearing, and the connecting bolts is consistent with the mass of the piston assembly, and the center of gravity is the same as the center of gravity of the piston assembly in the engine assembly. The upper and lower connecting rod bearings are in close contact with the crankshaft connecting rod journal of the engine, and the clearance between them is 30-60μm.
[0011] Preferably, the upper base of the tooling has a first mounting hole that runs vertically through both sides, and the lower base of the tooling has a second mounting hole that runs vertically through both sides, and the two first mounting holes are respectively connected to the two second mounting holes.
[0012] Preferably, the connecting bolt is installed between the connected first mounting hole and the second mounting hole.
[0013] Preferably, the connecting bolt consists of an integrally manufactured screw and an end, wherein the screw is threadedly connected in the first mounting hole and the second mounting hole, and the end is in contact with the inner wall of the first mounting hole.
[0014] Preferably, the inner ring surfaces of both the upper and lower bases of the tooling are provided with limiting grooves.
[0015] Preferably, limit blocks are fixedly installed on the outer ring surfaces of both the upper and lower connecting rod bearings, and the limit blocks are inserted into the inner wall of the limit groove.
[0016] This utility model discloses a testing fixture for the frictional work of an engine piston assembly, which has the following beneficial effects:
[0017] 1. This engine piston assembly friction work testing fixture consists of an upper fixture base, a lower fixture base, an upper connecting rod bearing, a lower connecting rod bearing, and connecting bolts. Its simple and clear structure facilitates operation, effectively reducing testing costs and time. Under the premise that the fixture's mass is consistent with the piston assembly's mass and its center of gravity is the same as the piston assembly's center of gravity during engine assembly, it can accurately simulate the actual working conditions of the piston assembly within the engine. By conducting tests under engine drag conditions, the friction work of the piston assembly can be more accurately reflected, providing a reliable basis for the engine's optimized design.
[0018] 2. The friction work testing fixture for this engine piston assembly has upper and lower connecting rod bearings that fit symmetrically with the inner rings of the upper and lower bases, respectively. The upper and lower connecting rod bearings also fit tightly with the engine crankshaft connecting rod journals, and the clearance between them is precisely controlled between 30-60 μm. This clearance range ensures a good sealing effect while avoiding additional friction and wear caused by excessively small clearances. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0020] Figure 1 This is a schematic diagram of the overall structure of this utility model;
[0021] Figure 2 This is a schematic diagram of the structure of the base of the tooling of this utility model;
[0022] Figure 3 This is a schematic diagram of the structure of the lower base of the tooling of this utility model;
[0023] Figure 4 This is a schematic diagram of the structure of the connecting bolt of this utility model;
[0024] Figure 5 This is a schematic diagram of the structure of the upper connecting rod bearing of this utility model.
[0025] In the diagram: 1. Upper base of the fixture; 11. First mounting hole; 2. Lower base of the fixture; 21. Second mounting hole; 3. Upper connecting rod bearing; 4. Lower connecting rod bearing; 5. Connecting bolt; 51. Screw; 52. End; 6. Limiting groove; 7. Limiting block. Detailed Implementation
[0026] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.
[0027] This utility model discloses a tooling for testing the frictional work of an engine piston assembly.
[0028] According to the appendix Figure 1-5 As shown, it includes:
[0029] The upper base 1 and the lower base 2 of the fixture are both set as semi-circles and are installed symmetrically.
[0030] Upper connecting rod bearing 3 and lower connecting rod bearing 4 are respectively fitted to the inner rings of the upper base 1 and the lower base 2 of the tooling, and the upper connecting rod bearing 3 and lower connecting rod bearing 4 are symmetrically arranged.
[0031] The upper connecting rod bearing 3 and the lower connecting rod bearing 4 fit tightly against the engine crankshaft connecting rod journal, and the clearance between them is 30-60μm.
[0032] Composed of an upper tooling base 1, a lower tooling base 2, an upper connecting rod bearing 3, a lower connecting rod bearing 4, and connecting bolts 5, the fixture features a simple and clear structure, convenient operation, and effectively reduces testing costs and time. Under the premise that the fixture's mass is consistent with the piston assembly's mass and its center of gravity is the same as the piston assembly's center of gravity during engine assembly, it can accurately simulate the actual working conditions of the piston assembly within the engine. By conducting tests under engine drag conditions, the frictional work of the piston assembly can be more accurately reflected, providing a reliable basis for the optimized design of the engine.
[0033] The upper connecting rod bearing 3 and the lower connecting rod bearing 4 are respectively fitted into the inner rings of the upper and lower bases and are symmetrically arranged. The upper connecting rod bearing 3 and the lower connecting rod bearing 4 are tightly fitted into the crankshaft connecting rod journal, and the fit clearance with the crankshaft connecting rod journal is precisely controlled between 30-60μm. This clearance range ensures a good sealing effect while avoiding additional friction and wear caused by excessively small clearances.
[0034] Furthermore, the upper base 1 of the tooling is provided with first mounting holes 11 that pass through vertically on both sides, and the lower base 2 of the tooling is provided with second mounting holes 21 that pass through vertically on both sides, and the two first mounting holes 11 are respectively connected to the two second mounting holes 21.
[0035] Furthermore, a connecting bolt 5 is provided between the connected first mounting hole 11 and the second mounting hole 21.
[0036] Furthermore, the connecting bolt 5 consists of an integrally manufactured screw 51 and an end 52. The screw 51 is threadedly connected to the first mounting hole 11 and the second mounting hole 21, and the end 52 is in contact with the inner wall of the first mounting hole 11.
[0037] This ensures a stable connection between the upper base 1 and the lower base 2 of the tooling, providing strong support for the tight fit between the upper connecting rod bearing 3 and the lower connecting rod bearing 4 and the crankshaft connecting rod journal.
[0038] Furthermore, limit grooves 6 are provided on the inner ring surfaces of both the upper base 1 and the lower base 2 of the tooling.
[0039] Furthermore, limit blocks 7 are fixedly installed on the outer ring surfaces of both the upper connecting rod bearing 3 and the lower connecting rod bearing 4, and the limit blocks 7 are inserted into the inner wall of the limit groove 6.
[0040] The limiting block 7 is inserted into the inner wall of the limiting groove 6, realizing the precise positioning between the upper connecting rod bearing 3 and the lower connecting rod bearing 4 and the upper base 1 and the lower base 2 of the tooling, ensuring the accurate position of the upper base 1 and the lower base 2 of the tooling during the assembly process, thereby further ensuring the tight fit and sealing effect between the upper base 1 and the lower base 2 of the tooling and the crankshaft connecting rod journal.
[0041] By adjusting the inner diameter and width of the upper base 1, lower base 2, upper connecting rod bearing 3, and lower connecting rod bearing 4, the tooling can be adapted to the diameter of the connecting rod journal of different engine crankshafts, thereby meeting the testing requirements of friction work of piston assemblies of different engine models and improving the versatility of the tooling.
[0042] Under engine reversing conditions, first test the engine's reversing torque T1. Then, disassemble the original piston assembly and reassemble the replaced piston assembly into the engine using a pre-assembled tooling. Under the same engine reversing conditions, test the engine's reversing torque T2 again.
[0043] Compare the differences in towing torque T1 and T2 under engine reversing conditions. Based on the relationship between friction work and torque, the friction work of the piston assembly can be accurately calculated. Specifically, friction work can be calculated as a function of the torque difference with parameters such as engine speed and test time. The specific calculation formula varies depending on the engine type and test conditions and needs to be determined based on the actual situation.
[0044] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.
Claims
1. An engine piston assembly frictional work testing tool, characterized by, include: The upper base (1) and the lower base (2) of the tooling are both set as semi-circular. A connecting bolt (5) is provided between the upper base (1) and the lower base (2), and the upper base (1) and the lower base (2) are symmetrically installed by the connecting bolt (5). Upper connecting rod bearing (3) and lower connecting rod bearing (4), wherein the upper connecting rod bearing (3) and lower connecting rod bearing (4) are respectively fitted to the inner rings of the upper base (1) and the lower base (2) of the tooling, and the upper connecting rod bearing (3) and lower connecting rod bearing (4) are symmetrically arranged; The overall mass of the upper base (1), lower base (2), upper connecting rod bearing (3), lower connecting rod bearing (4) and connecting bolt (5) of the tooling is consistent with the mass of the piston assembly, and the center of mass position is the same as the center of mass position of the piston assembly in the engine assembly. The upper connecting rod bearing (3) and lower connecting rod bearing (4) are closely fitted with the crankshaft connecting rod journal of the engine, and the clearance between them is 30-60μm.
2. An engine piston assembly frictional work test tooling according to claim 1, wherein, The upper base (1) of the tooling has a first mounting hole (11) that runs vertically through both sides, and the lower base (2) of the tooling has a second mounting hole (21) that runs vertically through both sides, and the two first mounting holes (11) are connected to the two second mounting holes (21) respectively.
3. An engine piston assembly frictional work test tooling according to claim 2, wherein, The connecting bolt (5) is installed between the connected first mounting hole (11) and the second mounting hole (21).
4. An engine piston assembly frictional work test tooling according to claim 3, wherein, The connecting bolt (5) consists of an integrally manufactured screw (51) and end (52). The screw (51) is threaded into the first mounting hole (11) and the second mounting hole (21), and the end (52) is in contact with the inner wall of the first mounting hole (11).
5. The engine piston assembly frictional work test tool of claim 1, wherein, Limiting grooves (6) are provided on the inner ring surfaces of the upper base (1) and lower base (2) of the tooling.
6. An engine piston assembly frictional work test tooling according to claim 5, wherein, Limiting blocks (7) are fixedly installed on the outer ring surfaces of the upper connecting rod bearing (3) and the lower connecting rod bearing (4), and the limiting blocks (7) are inserted into the inner wall of the limiting groove (6).