Auxiliary centering structure of a fatigue test fixture for a connecting rod of a diesel engine for vehicle

Abstract

The application discloses a kind of auxiliary centering structures of connecting rod fatigue test fixture of vehicle diesel engine, including the connecting rod small head fixture for connecting connecting rod small head end and the connecting rod big head fixture for connecting connecting rod big head end, the connecting rod small head fixture includes equipment upper connecting block, and the connecting rod big head fixture includes equipment lower connecting block;The equipment lower connecting block is set on base, and the base includes left and right adjusting pad plate for adjusting the left and right positions of the equipment lower connecting block and front and rear adjusting pad plate for adjusting the front and rear positions of the equipment lower connecting block, and the equipment upper connecting block and the equipment lower connecting block are connected with detachable centering rod assembly.The auxiliary centering structure of connecting rod fatigue test fixture of vehicle diesel engine designed in the application utilizes the high matching precision of centering rod to ensure the high-precision matching of equipment upper and lower connecting blocks, and avoids the coaxiality error of upper and lower connecting blocks.

Description

Technical Field

[0001] This invention relates to the technical field of testing equipment for automotive diesel engines, specifically to an auxiliary centering structure for a connecting rod fatigue testing fixture for automotive diesel engines. Background Technology

[0002] With the increasing power density of automotive diesel engines, the in-cylinder pressure and piston linear velocity have also increased significantly, leading to increased tensile and compressive stress on the connecting rods, and these stresses change more frequently. Therefore, specialized connecting rod fatigue testing and strength verification are required. Currently, most connecting rod fatigue testing and strength verification are performed on the professional MTS connecting rod fatigue testing machine.

[0003] Patent application number 202121239841.X, entitled "A Universal Centering and Self-Aligning Device for a Material Tensile or Fatigue Testing Equipment," discloses a universal centering and self-aligning device for a material tensile or fatigue testing equipment. One end of the outer sleeve is connected to the clamp on the main unit via a main unit connector, and the other end is connected to an end cap. The self-aligning base and the self-aligning pressure cap are both housed in the inner cavity formed by the outer sleeve and the end cap. Multiple horizontal adjusting screws are evenly arranged circumferentially on the outer sleeve. One end of the self-aligning base and the self-aligning pressure cap abuts against the outer sleeve and the end cap, respectively. The other ends of the self-aligning base and the self-aligning pressure cap abut against each other and are connected as one unit. One end of the self-aligning connecting rod is housed between the self-aligning base and the self-aligning pressure cap. A gap A is left between one end of the self-aligning connecting rod and the self-aligning base to allow the self-aligning connecting rod to swing. The self-aligning connecting rod and the self-aligning pressure cap are in spherical contact, and a gap B is left between the self-aligning connecting rod and the self-aligning pressure cap. The other end of the self-aligning connecting rod is an output end for connection. This invention has a simple structure, strong versatility, and is easy to operate. It can adjust the verticality at the same time as adjusting the horizontal centering.

[0004] Patent application number 201810111754.2, entitled "A Horizontal Linear Motor Driven High-Frequency Fatigue Testing Machine," discloses a horizontal linear motor driven high-frequency fatigue testing machine, including a linear motor, force sensor, sensor base, support, clamping device, base plate, mounting feet, damping pads, etc. The force sensor and linear motor are fixed to the left and right ends of the base plate, respectively. The force sensor is connected to the base plate through the sensor base. A sensor support with a built-in linear bearing is provided at the connecting rod between the force sensor end and the clamp. Front and rear supports with built-in linear bearings are also provided at the front and rear of the linear motor mover connecting rod. The testing machine base plate is mounted on a dedicated platform via mounting angles, and damping pads are arranged between the mounting angles and the platform to absorb vibration. This invention is used for high-frequency fatigue testing of various specimens under static and dynamic loads. The use of multiple linear bearing supports improves the motion stability of the linear motor mover and enhances the centering of the testing machine, providing a reliable and efficient device for high-precision high-frequency fatigue testing of materials.

[0005] Currently, the fixtures for connecting rod fatigue testing are divided into large and small end fixtures, which are independently processed and assembled. The alignment is adjusted by workers based on their experience. However, manual adjustment always has a certain degree of dispersion, which leads to a certain coaxiality error in the bearings of the large and small ends of the connecting rod. This causes the tension and compression forces that were originally perpendicular to the connecting rod to have a certain tilt angle, resulting in bending deformation of the connecting rod and affecting the efficiency and accuracy of the test. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the aforementioned background technology and provide a structure that can avoid manual adjustment errors, ensure test accuracy, and achieve vertical alignment of the fatigue test fixture for automotive diesel engine connecting rods.

[0007] To achieve this objective, the auxiliary centering structure of the automotive diesel engine connecting rod fatigue testing fixture designed in this invention includes a connecting rod small end clamp for connecting the small end of the connecting rod and a connecting rod large end clamp for connecting the large end of the connecting rod. The connecting rod small end clamp includes an upper connecting block, and the connecting rod large end clamp includes a lower connecting block. The lower connecting block is disposed on a base, and the base includes a left-right adjusting pad for adjusting the left-right position of the lower connecting block and a front-back adjusting pad for adjusting the front-back position of the lower connecting block. A detachable centering rod assembly is connected between the upper connecting block and the lower connecting block.

[0008] Furthermore, the connecting block on the device has an upper centering hole in the vertical direction, and the lower connecting block on the device has a lower centering hole in the vertical direction. The centering rod assembly is detachably connected between the upper centering hole and the lower centering hole.

[0009] Furthermore, the centering rod assembly includes a detachable upper centering rod coaxially disposed within the upper centering hole and a detachable lower centering rod coaxially disposed within the lower centering hole.

[0010] Furthermore, the lower centering rod is a stepped rod, which includes a first lower centering rod segment located above the lower centering hole and a second lower centering rod segment coaxially connected to the bottom of the first lower centering rod segment. The diameter of the first lower centering rod segment is larger than the diameter of the second lower centering rod segment. The first lower centering rod segment has a centering positioning groove along its axial direction that cooperates with the upper centering rod.

[0011] Furthermore, the top end of the upper centering rod is coaxially disposed at the bottom of the upper centering hole, and the lower part of the upper centering rod is coaxially disposed in the centering positioning groove; the bottom of the second lower centering rod segment is coaxially disposed in the lower centering hole.

[0012] Furthermore, the vertical distance between the bottom surface of the centering positioning groove and the upper centering hole is not less than the length of the upper centering rod.

[0013] Furthermore, the lower centering hole includes a smooth rod section that is clearance-fitted with the second lower centering rod section and a threaded rod section that is coaxially connected to the bottom of the smooth rod section and opened inside the lower connecting block of the device.

[0014] Furthermore, the left and right adjustment pads are slidably disposed above the front and rear adjustment pads, and the lower connecting block of the device is slidably disposed above the left and right adjustment pads.

[0015] Furthermore, the left and right adjustment pad is provided with a left and right adjustment groove along the left and right direction, and a left and right sliding pad is slidably disposed in the left and right adjustment groove, and the lower connecting block of the device is fixed on the left and right sliding pad.

[0016] Furthermore, the front and rear adjusting pads are provided with front and rear adjusting grooves along the front and rear direction, and front and rear sliding pads are slidably disposed in the front and rear adjusting grooves, and the left and right adjusting pads are fixed on the front and rear sliding pads.

[0017] The beneficial effects of this invention are as follows: In the auxiliary centering structure of the automotive diesel engine connecting rod fatigue testing fixture designed in this invention, the high fitting accuracy of the centering rod ensures the high-precision fit of the upper and lower connecting blocks, avoiding coaxiality errors between the upper and lower connecting blocks. The position of the lower connecting block can be fully adjusted using left-right and front-back adjusting shims, further ensuring the coaxiality of the upper and lower connecting blocks. The centering hole and the connecting rod locking hole of the lower connecting block are the same hole, processed in sections to ensure that the lower connecting block can accurately center with the upper connecting block and connect with the connecting rod big end locking block. The lower connecting block also has a countersunk locking hole, which allows for connection with the equipment without interfering with the connecting rod big end locating pin. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the auxiliary centering structure of the fatigue testing fixture for connecting rods of automotive diesel engines in this invention;

[0019] Figure 2 This is a top view of the base structure in this invention;

[0020] Figure 3 This is a schematic diagram of the left and right sliding pads in this invention;

[0021] Figure 4 This is a schematic diagram of the connection structure of the fatigue testing fixture for connecting rods of automotive diesel engines in this invention;

[0022] Figure 5 This is a schematic diagram of the lubrication oil passage arrangement of the connecting structure of the automotive diesel engine connecting rod fatigue test fixture in this invention;

[0023] Figure 6 This is a left view of the structure of the connecting block on the device in this invention;

[0024] Figure 7 This is a schematic diagram of the snap ring structure in this invention;

[0025] Among them, 101—connecting rod small end clamp (101.1—connecting block on the equipment, 101.2—connecting rod small end positioning pin, 101.3—connecting rod small end locking block), 102—connecting rod, 103—connecting rod large end clamp (103.1—connecting block below the equipment, 103.2—connecting rod large end positioning pin, 103.3—connecting rod large end locking block), 104

[0026] —Return oil pan, 105—Filter element, 106—Oil tank, 107—Oil pump, 108—Cooler, 109—Connecting rod small end locating pin hole, 110—Snap ring, 111—Small end axial lubrication passage, 112—Small end bearing lubrication groove, 113—Connecting rod axial lubrication passage, 114—Large end axial lubrication passage, 115—Large end bearing lubrication groove, 116—Upper centering hole, 117—Lower centering hole (117.1—Smooth rod section, 117.2—Threaded rod section), 118—Hydraulic equipment connection hole, 119—Oval hole, 120—Connecting rod Small end locking bolt, 121—connecting rod small end locking nut, 122—connecting rod large end locking bolt, 123—base connecting bolt, 124—base connecting hole, 201—base (201.1—left and right adjusting pad, 201.2—front and rear adjusting pad), 202—upper centering rod, 203—lower centering rod (203.1—first lower centering rod section, 203.2—second lower centering rod section), 204—centering positioning groove, 205—left and right adjusting groove, 206—left and right sliding pad, 207—front and rear adjusting groove, 208—front and rear sliding pad. Detailed Implementation

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. In the description of the present invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0028] like Figure 1The auxiliary centering structure of the fatigue testing fixture for automotive diesel engine connecting rods shown in Figure 3 includes a connecting rod small end clamp 101 for connecting the small end of the connecting rod and a connecting rod large end clamp 103 for connecting the large end of the connecting rod. The connecting rod small end clamp 101 includes an upper connecting block 101.1, and the connecting rod large end clamp 103 includes a lower connecting block 103.1. The lower connecting block 103.1 is mounted on a base 201, which includes a left-right adjusting pad 201.1 for adjusting the left-right position of the lower connecting block 103.1 and a front-rear adjusting pad 201.2 for adjusting the front-back position of the lower connecting block 103.1. A detachable centering rod assembly is connected between the upper connecting block 101.1 and the lower connecting block 103.1.

[0029] The connecting block 101.1 on the equipment has an upper centering hole 116 in the vertical direction, and the lower connecting block 103.1 on the equipment has a lower centering hole 117 in the vertical direction. A centering rod assembly is detachably connected between the upper centering hole 116 and the lower centering hole 117.

[0030] The centering rod assembly includes a detachable upper centering rod 202 coaxially disposed within the upper centering hole 116 and a detachable lower centering rod 203 coaxially disposed within the lower centering hole 117.

[0031] The lower centering rod 203 is a stepped rod, which includes a first lower centering rod section 203.1 located above the lower centering hole 117 and a second lower centering rod section 203.2 coaxially connected to the bottom of the first lower centering rod section 203.1. The diameter of the first lower centering rod section 203.1 is larger than the diameter of the second lower centering rod section 203.2. The first lower centering rod section 203.1 has a centering positioning groove 204 along its axial direction that mates with the upper centering rod 202.

[0032] The top end of the upper centering rod 202 is coaxially disposed at the bottom of the upper centering hole 116, and the lower part of the upper centering rod 202 is coaxially disposed in the centering positioning groove 204; the bottom of the second lower centering rod section 203.2 is coaxially disposed in the lower centering hole 117.

[0033] The vertical distance between the bottom groove surface of the centering positioning groove 204 and the upper centering hole 116 is not less than the length of the upper centering rod 202.

[0034] The lower centering hole 117 includes a smooth rod section 117.1 that is clearance-fitted with the second lower centering rod section 203.2 and a threaded rod section 117.2 that is coaxially connected to the bottom of the smooth rod section 117.1 and opened inside the lower connecting block 103.1 of the equipment.

[0035] The left and right adjustment pad 201.1 is slidably positioned above the front and rear adjustment pad 201.2, and the lower connecting block 103.1 is slidably positioned above the left and right adjustment pad 201.1.

[0036] The left and right adjustment pad 201.1 has a left and right adjustment groove 205 along the left and right direction, and a left and right sliding pad 206 is slidably arranged in the left and right adjustment groove 205. The lower connecting block 103.1 of the equipment is fixed on the left and right sliding pad 206.

[0037] The front and rear adjustment pad 201.2 has a front and rear adjustment groove 207 along the front and rear direction, and a front and rear sliding pad 208 is slidably arranged in the front and rear adjustment groove 207. The left and right adjustment pad 201.1 is fixed on the front and rear sliding pad 208.

[0038] like Figure 4 The connecting structure of the automotive diesel engine connecting rod fatigue test fixture shown in Figure 7 includes a connecting rod small end clamp 101 for connecting the small end of the connecting rod and a connecting rod big end clamp 103 for connecting the large end of the connecting rod. A return oil pan 104 for recovering lubricating oil is provided below the connecting rod big end clamp 103. The return oil pan 104 is connected to the connecting rod small end clamp 101, connecting rod 102 and connecting rod big end clamp 103 by a forced cooling lubricating oil circuit. The connecting rod small end clamp 101, connecting rod 102 and connecting rod big end clamp 103 are all provided with lubricating oil passages that communicate with the forced cooling lubricating oil circuits and can return lubricating oil to the return oil pan 104.

[0039] The forced cooling lubrication circuit includes a filter element 105, an oil tank 106, an oil pump 107, and a cooler 108, which are connected in series with the return oil pan 104 via pipelines. The oil outlet of the cooler 108 is connected to the connecting rod small end clamp 101, the connecting rod 102, and the connecting rod big end clamp 103 via at least three pipelines.

[0040] The connecting rod small end clamp 101 has a connecting rod small end locating pin hole 109 perpendicular to the axial installation direction of the connecting rod 102. The connecting rod small end clamp 101 is connected to the connecting rod 102 by a connecting rod small end locating pin 101.2 that passes perpendicularly through the small end of the connecting rod and is coaxially disposed in the connecting rod small end locating pin hole 109. A bearing that mates with the connecting rod small end locating pin 101.2 is disposed in the connecting rod small end locating pin hole 109. A retaining ring 110 for positioning the connecting rod small end locating pin 101.2 is disposed in the connecting rod small end locating pin hole 109. The lubrication channels in the connecting rod small end clamp 101 include a small end axial lubrication channel 111 arranged axially along the connecting rod small end locating pin hole 109 and a small end bearing lubrication groove 112 that communicates with the small end axial lubrication channel 111 and is arranged circumferentially along the mounting hole of the bearing that mates with the connecting rod small end locating pin 101.2.

[0041] The lubrication channels opened in the connecting rod 102 include the connecting rod axial lubrication channel 113 arranged along the central axial direction of the connecting rod 102.

[0042] The connecting rod big end clamp 103 has a connecting rod big end locating pin hole perpendicular to the axial installation direction of the connecting rod 102. The connecting rod big end clamp 103 is connected to the connecting rod 102 through a connecting rod big end locating pin 103.2 that passes perpendicularly through the connecting rod big end and is located in the connecting rod big end locating pin hole. A bearing that mates with the connecting rod big end locating pin 103.2 is provided in the connecting rod big end locating pin hole. A retaining ring 110 for positioning the connecting rod big end locating pin 103.2 is provided in the connecting rod big end locating pin hole. The lubrication channels in the connecting rod big end clamp 103 include a big end axial lubrication channel 114 arranged axially along the connecting rod big end locating pin hole and a big end bearing lubrication groove 115 that communicates with the big end axial lubrication channel 114 and is arranged circumferentially along the mounting hole of the bearing that mates with the connecting rod big end locating pin 103.2.

[0043] The connecting rod big end clamp 103 is mounted on the base 201, and the oil return plate 104 is located below the base 201. The base 201 includes a left-right adjusting pad 201.1 for adjusting the left and right position of the connecting rod big end clamp 103 and a front-back adjusting pad 201.2 for adjusting the front-back position of the connecting rod big end clamp 103.

[0044] In the auxiliary centering structure of the automotive diesel engine connecting rod fatigue testing fixture designed in this invention, the high-precision fit of the centering rod ensures the high-precision fit of the upper and lower connecting blocks, avoiding coaxiality errors between the upper and lower connecting blocks. The position of the lower connecting block 103.1 can be fully adjusted using left-right and front-back adjusting shims, further ensuring the coaxiality of the upper and lower connecting blocks. The centering hole and connecting rod locking hole of the lower connecting block 103.1 are the same hole, produced through segmented machining. This ensures that the lower connecting block 103.1 can accurately center with the upper connecting block 101.1 and connect with the connecting rod big end locking block 103.3. The lower connecting block 103.1 also has a countersunk locking hole, which allows for connection to the equipment without interfering with the connecting rod big end locating pin 103.2. After the upper and lower connecting blocks are aligned, the centering rod assembly is removed for connection to the automotive diesel engine connecting rod fatigue testing fixture.

[0045] The connecting structure of the automotive diesel engine connecting rod fatigue testing fixture designed in this invention features a forced cooling and lubrication module, ensuring that the connecting rod 102 remains at a constant temperature and preventing thermal deformation caused by excessively high local temperatures, thus preventing premature breakage of the connecting rod 102. In the locking module designed in this invention, the connecting rod 102 is locked by a large and small end locating pin, and the mating surfaces of the large and small end locating pins have a retaining spring structure to prevent lateral movement of the locating pins. The connecting block 101.1 on the equipment in this invention has a bolt self-locking structure, which avoids interference between the bolts and the hydraulic equipment.

[0046] It should be noted that the above description of the technical solutions is exemplary, and this specification may be embodied in different forms and should not be construed as limiting itself to the technical solutions set forth herein. Rather, providing these descriptions will ensure that the disclosure of this invention is thorough and complete, and will fully convey the scope of this specification to those skilled in the art. Furthermore, the technical solutions of this invention are defined only by the scope of the claims. When using terms such as "comprising," "having," and "including" as described in this specification, there may also be another part or other components, and the terms used are generally singular but may also represent plural forms. It should be pointed out that although various different components may appear and be described in this specification using terms such as "first," "second," "top," "bottom," "one side," "the other side," "one end," "the other end," etc., these components and parts should not be limited by these terms. These terms are only used to distinguish one component and part from another component and part. For example, without departing from the scope of this specification, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component; top and bottom components may, in certain cases, be interchanged or converted; components at one end and at the other end may have the same or different performance characteristics. When describing positional relationships, for example, when the positional order is described as "on," "above," "below," and "next," situations where they are not in contact or are in contact may be included, unless words or terms such as "exactly" or "directly" are used. If it is mentioned that the first element is "on" the second element, it does not mean that the first element must be above the second element in the drawing. The upper and lower parts of the components will change depending on the viewing angle and orientation. Therefore, in the drawings or in actual construction, situations where the first element is "on" the second element can include situations where the first element is "below" the second element and situations where the first element is "above" the second element. When describing temporal relationships, situations where the steps are not consecutive may be included when describing "after," "following," "subsequently," and "before," unless "exactly" or "directly" is used. Features of various embodiments of the invention may be combined or spliced ​​together in part or in whole, and may be implemented in various different configurations as will be fully understood by those skilled in the art. Embodiments of the invention may be implemented independently of each other or may be implemented together in an interdependent relationship.

[0047] Finally, it should be noted that the above embodiments are merely representative examples of the present invention. Obviously, the present invention is not limited to the above embodiments and many variations are possible. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention should be considered within the protection scope of the present invention.

Claims

1. An auxiliary alignment structure for a fatigue testing fixture for automotive diesel engine connecting rods, comprising a connecting rod small end clamp (101) for connecting the small end of the connecting rod and a connecting rod big end clamp (103) for connecting the large end of the connecting rod, characterized in that: The small end clamp (101) of the connecting rod includes an upper connecting block (101.1), and the large end clamp (103) of the connecting rod includes a lower connecting block (103.1). The lower connecting block (103.1) is disposed on a base (201). The base (201) includes a left-right adjusting pad (201.1) for adjusting the left-right position of the lower connecting block (103.1) and a front-back adjusting pad (201.2) for adjusting the front-back position of the lower connecting block (103.1). A detachable centering rod assembly is connected between the upper connecting block (101.1) and the lower connecting block (103.1). The upper connecting block (101.1) of the device has an upper centering hole (116) in the vertical direction, and the lower connecting block (103.1) of the device has a lower centering hole (117) in the vertical direction. The centering rod assembly is detachably connected between the upper centering hole (116) and the lower centering hole (117). The centering rod assembly includes a detachable upper centering rod (202) coaxially disposed in the upper centering hole (116) and a detachable lower centering rod (203) coaxially disposed in the lower centering hole (117); The lower centering rod (203) is a stepped rod, which includes a first lower centering rod section (203.1) located above the lower centering hole (117) and a second lower centering rod section (203.2) coaxially connected to the bottom of the first lower centering rod section (203.1). The diameter of the first lower centering rod section (203.1) is larger than the diameter of the second lower centering rod section (203.2). The first lower centering rod section (203.1) has a centering positioning groove (204) along its axial direction that cooperates with the upper centering rod (202). The top end of the upper centering rod (202) is coaxially disposed at the bottom of the upper centering hole (116), and the lower part of the upper centering rod (202) is coaxially disposed in the centering positioning groove (204); the bottom of the second lower centering rod section (203.2) is coaxially disposed in the lower centering hole (117); The vertical distance between the bottom groove surface of the centering positioning groove (204) and the upper centering hole (116) is not less than the length of the upper centering rod (202).

2. The auxiliary centering structure of the fatigue testing fixture for automotive diesel engine connecting rods as described in claim 1, characterized in that: The lower centering hole (117) includes a smooth rod section (117.1) that is clearance-fitted with the second lower centering rod section (203.2) and a threaded rod section (117.2) that is coaxially connected to the bottom of the smooth rod section (117.1) and opened inside the lower connecting block (103.1) of the device.

3. The auxiliary centering structure of the fatigue testing fixture for automotive diesel engine connecting rods as described in claim 1, characterized in that: The left and right adjustment pad (201.1) is slidably disposed above the front and rear adjustment pad (201.2), and the lower connecting block (103.1) of the device is slidably disposed above the left and right adjustment pad (201.1).

4. The auxiliary centering structure of the automotive diesel engine connecting rod fatigue testing fixture as described in claim 3, characterized in that: The left and right adjustment pad (201.1) has a left and right adjustment groove (205) in the left and right direction. A left and right sliding pad (206) is slidably arranged in the left and right adjustment groove (205). The lower connecting block (103.1) of the equipment is fixed on the left and right sliding pad (206).

5. The auxiliary centering structure of the fatigue testing fixture for automotive diesel engine connecting rods as described in claim 3 or 4, characterized in that: The front and rear adjustment pad (201.2) has a front and rear adjustment groove (207) in the front and rear direction. A front and rear sliding pad (208) is slidably arranged in the front and rear adjustment groove (207). The left and right adjustment pad (201.1) is fixed on the front and rear sliding pad (208).

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