A temperature-adjustable piston pin wear and fatigue coupling test device for high-power diesel engines

Abstract

The present invention provides a temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine. The lower end of the pin seat is fixedly connected to the upper end of the machine platform, a boss is arranged on the upper end of the pin seat, a first through hole is arranged in the middle of the loading rod, the outer periphery of the boss is located in the first through hole, a second through hole is arranged on one side of the loading rod, a third through hole is arranged on the boss, the outer periphery of the piston pin is located in the second through hole and the third through hole respectively, the two ends of the loading rod are slidably connected to a loading cylinder respectively, the pin seat is located between the two loading cylinders, and each loading cylinder is used to provide axial loading to the loading rod. The test device described in the present invention can simulate the load of the maximum explosion pressure working condition and the maximum inertia force working condition of the piston pin, the test device can realize the periodic cycle loading of pressure and tension, and truly reflect the stress condition of the engine piston pin; at the same time, a rapid heater is installed in the middle of the piston pin, and a temperature sensor is installed on the piston pin support seat, which can realize the online detection function of the piston pin temperature in real time.

Description

Technical Field

[0001] The invention belongs to the field of piston pin detection, and in particular relates to a temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine. Background Art

[0002] During engine operation, the maximum load on the piston pin occurs under the conditions of maximum explosion pressure and maximum inertia force. Under the condition of maximum explosion pressure, the piston bears the high-temperature, high-pressure gas load generated by cylinder combustion to push the piston to run in the cylinder. The piston is connected to the piston pin, so the piston pin will also bear the same load. At this time, the piston pin bears the maximum compression load; under the condition of maximum inertia force, the piston pin makes high-speed reciprocating linear motion with other piston components, and the piston pin bears the maximum tensile load. Therefore, the piston pin bears periodic compression-tensile load during engine operation.

[0003] The existing piston pin fatigue test device can only apply a unidirectional load to the piston pin, and only simulates the compression load generated by the maximum explosion pressure condition of the diesel engine. The load applied by the test device to the piston pin is a compressive load, which cannot accurately simulate the actual working load of the piston pin; the piston pin temperature is determined by the hydraulic oil temperature and the ambient temperature, and the influence of temperature changes on the fatigue performance of the piston pin cannot be considered; the existing piston pin fatigue test device usually uses the original engine piston and the piston pin to carry out fatigue tests at the same time, and the piston often reaches the fatigue limit first and cracks, so the fatigue strength value of the piston pin cannot be determined, and only the range of the piston fatigue strength is known; with the advancement of engine technology, the maximum combustion pressure is gradually increased, and the piston test load is about to reach the use capacity of the hydraulic system equipment, resulting in the situation that the piston pin fatigue test cannot be carried out as scheduled. Summary of the invention

[0004] In view of this, the present invention aims to provide a temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine, so as to solve the problem that the detection equipment in the prior art cannot meet the requirements of the piston pin fatigue test.

[0005] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0006] A temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine comprises a pin seat, the lower end of the pin seat is fixedly connected to the upper end of a machine platform, a boss is arranged at the upper end of the pin seat, a first through hole is arranged in the middle of a loading rod, the periphery of the boss is located in the first through hole, a second through hole is arranged on one side of the loading rod, the second through hole and the first through hole are arranged perpendicular to each other, a third through hole is arranged on the boss, the third through hole and the second through hole are arranged coaxially, the periphery of the piston pin is respectively located in the second through hole and the third through hole, the two ends of the loading rod are respectively slidably connected to a loading cylinder, and the two loading cylinders are symmetrically arranged, the pin seat is located between the two loading cylinders, and each loading cylinder is used to provide axial load to the loading rod.

[0007] Furthermore, a retaining ring is arranged in the second through hole, and the retaining ring is used to limit the relative position of the piston pin.

[0008] Furthermore, the loading cylinder includes a cylinder head, a piston head and a cylinder body. The periphery of the cylinder body is fixedly connected to the upper end of the machine platform. A sliding cavity is provided in the middle of the cylinder body. The periphery of the piston head is slidably connected to the side wall of the sliding cavity. One end of the loader is fixedly connected to one end of the piston head. The cylinder head is installed at the other end of the cylinder body. A first oil cavity is provided between the other end of the piston head and one side of the cylinder head. A pipe body is installed on the other side of the cylinder head, and the pipe body is used to transport high-pressure medium into the first oil cavity.

[0009] Furthermore, a heat-resistant rubber ring is arranged between one side of the cylinder cover and one end of the cylinder body.

[0010] Furthermore, a sealing rubber ring is arranged on the periphery of the piston head, and the periphery of the piston head is sealed and connected to the inner wall of the cylinder body through the sealing rubber ring.

[0011] Furthermore, a first oil filling hole is provided on the boss, a second gap is provided on the periphery of the piston pin and the side wall of the third through hole, the outlet end of the first oil filling hole is connected to the second gap, a second oil filling hole is provided on the loading rod, a third gap is provided on the periphery of the piston pin and the side wall of the second through hole, the outlet end of the second oil filling hole is connected to the third gap, an oil collection pool is provided on the upper end of the machine platform, the inlet end of the first oil filling hole and the inlet end of the second oil filling hole are respectively connected to the oil collection pool through oil inlet pipes, the oil collection pool is filled with lubricating oil, and an oil pump is arranged on the oil inlet pipe.

[0012] Furthermore, a fourth through hole is provided in the middle of the piston pin, and a heater is installed in the fourth through hole.

[0013] Furthermore, a plurality of fifth through holes are evenly distributed on the boss, and a temperature sensor for detecting the temperature of the piston pin is installed in each of the fifth through holes.

[0014] Furthermore, a slope is provided on the upper end of the machine platform for introducing lubricating oil on the machine platform into the oil collection pool.

[0015] Furthermore, a swing cylinder is installed on the upper end of the machine platform, and the output end of the swing rod is fixedly connected to one end of the piston pin, and the swing cylinder can drive the piston pin to swing relative to the boss and the loading rod.

[0016] Compared with the prior art, the temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine described in the present invention has the following beneficial effects:

[0017] (1) The temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine described in the present invention can simulate the load of the maximum explosion pressure condition and the maximum inertia force condition of the piston pin. The test device can realize periodic cycle loading of pressure and tension, and truly reflect the stress condition of the engine piston pin. At the same time, a rapid heater is installed in the middle of the piston pin, and a temperature sensor is installed on the piston pin support seat, which can realize the online detection function of the piston pin temperature in real time. It is a piston pin fatigue test device with an adjustable temperature function.

[0018] (2) The temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine described in the present invention uses a non-standard piston head as a companion test piece. The material strength is higher than that of the piston pin and the stiffness is more than 3 times that of the piston pin. The piston pin load of the test piece is equal to the hydraulic system oil pressure value multiplied by the piston top projection area, that is, when the equipment provides a certain hydraulic oil pressure value, the test load increases accordingly after the piston head area is increased. A small equipment capacity can also be used to carry out a high-power diesel engine piston pin fatigue test.

[0019] (3) The temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine described in the present invention has a swing rod arranged in the test device, which can test the influence of elliptical deformation on the fatigue strength of the piston pin, can test the influence of bending deformation on the fatigue strength of the piston pin, and can consider the fatigue strength test of the piston pin under the actual load wear state of the pin seat bushing and the piston pin.

[0020] (4) The temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine described in the present invention can perform fatigue tests on piston pins of any diameter by adjusting the structural dimensions of the test device. The fatigue test device can be extended to fatigue tests on other shafts. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0022] Figure 1 It is a structural schematic diagram of a temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine according to an embodiment of the present invention;

[0023] Figure 2 It is a cross-sectional schematic diagram of a temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine according to an embodiment of the present invention;

[0024] Figure 3 It is a structural schematic diagram of the pin seat according to an embodiment of the present invention;

[0025] Figure 4 This is a schematic structural diagram of the cooperation between the loading rod and the piston head according to an embodiment of the present invention.

[0026] Description of reference numerals:

[0027] 1-pin seat; 11-boss; 12-fifth through hole; 2-machine table; 3-loading rod; 4-piston pin; 5-loading cylinder; 51-cylinder head; 52-piston head; 53-cylinder body; 54-tube body; 55-heat-resistant rubber ring; 56-sealing rubber ring; 6-oil inlet pipe; 7-heater; 8-swing cylinder. DETAILED DESCRIPTION

[0028] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0029] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0030] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0031] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0032] like Figure 1-4As shown, a temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine comprises a pin seat 1, the lower end of the pin seat 1 is fixedly connected to the upper end of a machine platform 2, a boss 11 is arranged on the upper end of the pin seat 1, a first through hole is arranged in the middle of a loading rod 3, the periphery of the boss 11 is located in the first through hole, a second through hole is arranged on one side of the loading rod 3, the second through hole and the first through hole are arranged perpendicular to each other, a third through hole is arranged on the boss 11, the third through hole is arranged coaxially with the second through hole, the periphery of a piston pin 4 is respectively located in the second through hole and the third through hole, both ends of the loading rod 3 are respectively slidably connected to a loading cylinder 5, and the two loading cylinders 5 are symmetrically arranged with each other, the pin seat 1 is located between the two loading cylinders 5, and each loading cylinder 5 is used to periodically apply a load to the loading rod 3 according to a preset phase relationship of the experiment, a retaining ring is arranged in the second through hole, and the retaining ring is used to limit the relative position of the piston pin 4. This test device uses a non-standard piston head 52 as a companion test piece, the material strength of which is higher than that of the piston pin 4 and the rigidity is more than 3 times that of the piston pin 4; the load of the test piece piston pin 4 is equal to the hydraulic system oil pressure value multiplied by the piston top projection area, that is, when the equipment provides a certain hydraulic oil pressure value, the test load will increase accordingly after increasing the area of ​​the piston head 52, and a small equipment capacity can also be used to carry out fatigue tests on the piston pin 4 of a high-power diesel engine.

[0033] The loading cylinder 5 includes a cylinder cover 51, a piston head 52 and a cylinder body 53. The periphery of the cylinder body 53 is fixedly connected to the upper end of the machine platform 2. A sliding cavity is provided in the middle of the cylinder body 53. The periphery of the piston head 52 is slidably connected to the side wall of the sliding cavity. One end of the loader is fixedly connected to one end of the piston head 52. The other end of the cylinder body 53 is installed with the cylinder cover 51. A first oil cavity is provided between the other end of the piston head 52 and one side of the cylinder cover 51. A pipe body 54 is installed on the other side of the cylinder cover 51, and the pipe body 54 is used to transport high-pressure medium into the first oil cavity. A heat-resistant rubber ring 55 is provided between one side of the cylinder cover 51 and one end of the cylinder body 53. A sealing rubber ring 56 is provided on the periphery of the piston head 52. The periphery of the piston head 52 is sealed and connected to the inner wall of the cylinder body 53 through the sealing rubber ring 56. The structural dimensions of the test device can be adjusted to perform fatigue assessment tests on piston pins 4 of any diameter. The fatigue test device can be extended to fatigue tests of other shafts.

[0034] A first oil filling hole is provided on the boss 11, a second gap is provided on the periphery of the piston pin 4 and the side wall of the third through hole, the outlet end of the first oil filling hole is connected to the second gap, a second oil filling hole is provided on the loading rod 3, a third gap is provided on the periphery of the piston pin 4 and the side wall of the second through hole, the outlet end of the second oil filling hole is connected to the third gap, an oil collection pool is provided on the upper end of the machine 2, the inlet end of the first oil filling hole and the inlet end of the second oil filling hole are connected to the oil collection pool through the oil inlet pipe 6 respectively, the oil collection pool is filled with lubricating oil, and an oil pump is arranged on the oil inlet pipe 6.

[0035] A fourth through hole is provided in the middle of the piston pin 4, in which a heater 7 is installed, and a plurality of fifth through holes 12 are evenly distributed on the boss 11, in each of which a temperature sensor for detecting the temperature of the piston pin 4 is installed. The aforementioned structure can simulate the load of the maximum explosion pressure working condition and the maximum inertia force working condition of the piston pin 4. The test device can realize periodic cycle loading of pressure and tension, truly reflects the stress condition of the engine piston pin 4, can assess the influence of elliptical deformation on the fatigue strength of the piston pin 4, and can assess the influence of bending deformation on the fatigue strength of the piston pin 4; at the same time, a quick heater 7 is installed in the middle of the piston pin 4, and a temperature sensor is installed on the support seat of the piston pin 4, which can realize the online detection function of the temperature of the piston pin 4 in real time, and is a piston pin 4 fatigue test device with adjustable temperature function.

[0036] A slope is provided on the upper end of the machine 2 for introducing the lubricating oil on the surface of the machine 2 into the oil collection pool. A swing cylinder 8 is installed on the upper end of the machine 2, and the output end of the swing rod is fixedly connected to one end of the piston pin 4, and the swing cylinder 8 can drive the piston pin 4 to swing coaxially with respect to the boss 11 and the loading rod 3 in a certain arc. The swing cylinder 8 is a prior art. By setting the swing rod, the fatigue strength of the piston pin 4 under the actual load wear state of the pin seat 1 bushing and the piston pin 4 can be considered.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A temperature-adjustable piston pin wear and fatigue coupling test device for high-power diesel engines, characterized by: The invention comprises a pin seat (1), the lower end of the pin seat (1) is fixedly connected to the upper end of the machine platform (2), a boss (11) is arranged at the upper end of the pin seat (1), a first through hole is arranged in the middle of the loading rod (3), the outer periphery of the boss (11) is located in the first through hole, a second through hole is arranged on one side of the loading rod (3), the second through hole and the first through hole are arranged perpendicular to each other, a third through hole is arranged on the boss (11), the third through hole and the second through hole are arranged coaxially, the outer periphery of the piston pin (4) is respectively located in the second through hole and the third through hole, the two ends of the loading rod (3) are respectively slidably connected to a loading cylinder (5), and the two loading cylinders (5) are arranged symmetrically to each other, the pin seat (1) is located between the two loading cylinders (5), and each loading cylinder (5) is used to provide loading to the loading rod (3); The loading oil cylinder (5) comprises a cylinder cover (51), a piston head (52) and a cylinder body (53); the outer periphery of the cylinder body (53) is fixedly connected to the upper end of the machine platform (2); a sliding cavity is provided in the middle of the cylinder body (53); the outer periphery of the piston head (52) is slidably connected to the side wall of the sliding cavity; one end of the loading member is fixedly connected to one end of the piston head (52); the other end of the cylinder body (53) is installed with the cylinder cover (51); a first oil cavity is provided between the other end of the piston head (52) and one side of the cylinder cover (51); a pipe body (54) is installed on the other side of the cylinder cover (51); and the pipe body (54) is used to transport high-pressure medium into the first oil cavity.

2. The temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine according to claim 1 is characterized in that: A retaining ring is arranged in the second through hole, and the retaining ring is used to limit the relative position of the piston pin (4).

3. The temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine according to claim 1 is characterized in that: A heat-resistant rubber ring (55) is arranged between one side of the cylinder cover (51) and one end of the cylinder body (53).

4. The high-power diesel engine temperature-adjustable piston pin wear and fatigue coupling test device according to claim 1 is characterized by: A sealing rubber ring (56) is arranged on the periphery of the piston head (52), and the periphery of the piston head (52) is sealingly connected to the inner wall of the cylinder body (53) through the sealing rubber ring (56).

5. The high-power diesel engine temperature-adjustable piston pin wear and fatigue coupling test device according to claim 1 is characterized by: A first oil filling hole is provided on the boss (11), a second gap is provided on the periphery of the piston pin (4) and the side wall of the third through hole, the outlet end of the first oil filling hole is connected to the second gap, a second oil filling hole is provided on the loading rod (3), a third gap is provided on the periphery of the piston pin (4) and the side wall of the second through hole, the outlet end of the second oil filling hole is connected to the third gap, an oil collection pool is provided on the upper end of the machine (2), the inlet end of the first oil filling hole and the inlet end of the second oil filling hole are respectively connected to the oil collection pool through an oil inlet pipe (6), the oil collection pool is filled with lubricating oil, and an oil pump is provided on the oil inlet pipe (6).

6. The high-power diesel engine temperature-adjustable piston pin wear and fatigue coupling test device according to claim 1 is characterized by: A fourth through hole is provided in the middle of the piston pin (4), and a heater (7) is installed in the fourth through hole.

7. The high-power diesel engine temperature-adjustable piston pin wear and fatigue coupling test device according to claim 1 is characterized by: A plurality of fifth through holes (12) are evenly distributed on the boss (11), and a temperature sensor for detecting the temperature of the piston pin (4) is installed in each fifth through hole (12).

8. The temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine according to claim 1 is characterized by: The upper end of the machine platform (2) is provided with a slope surface for introducing lubricating oil on the surface of the machine platform (2) into the oil collection pool.

9. The temperature-adjustable piston pin wear and fatigue coupling test device for a high-power diesel engine according to claim 1 is characterized in that: A swing cylinder (8) is installed on the upper end of the machine platform (2), and the output end of the swing rod is fixedly connected to one end of the piston pin (4), and the swing cylinder (8) can drive the piston pin (4) to swing relative to the boss (11) and the loading rod (3).

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