Engine valve stem height measuring aid

Abstract

The utility model relates to an engine valve rod height measurement auxiliary tool, contain main part and be located the boss of both sides of main part, main part and boss are integral type structure, the middle part of main part is equipped with a first circular through -hole, the position of first circular through -hole corresponds with oil atomizer hole and is used for the auxiliary positioning 4 valve rods, the four directions of front and back left and right of first circular through -hole are cross -shaped symmetry ring cloth again four second circular through -holes, the position of second circular through -hole corresponds with the position of corresponding engine single -cylinder upper portion 4 valves one -to -one correspondence, the utility model discloses have realized indirectly to obtain the valve subsidence amount without disassembling the cylinder cover, reduced the maintenance work hour, avoided the oil waste and cylinder cover pollution.

Description

Technical Field

[0001] This utility model relates to the technical field of engine component testing tools, specifically to an auxiliary tool for measuring engine valve stem height. Background Technology

[0002] In engine aftermarket repairs or cylinder head inspections, technicians need to determine the degree of wear or deformation of the valve assembly by measuring the "valve deflection" (the distance between the valve sealing surface and the cylinder head combustion chamber surface). Traditional measurement methods have significant drawbacks: 1. The operation is cumbersome and time-consuming: The cylinder head must first be completely removed from the engine, and then a special flipping tool must be used to rotate the cylinder head 180° (the valve sinking measurement point is located on the lower surface of the cylinder head). The whole process takes 2-3 hours, which greatly extends the maintenance time. 2. Waste of resources and cleaning burden: When the cylinder head is flipped, a large amount of residual engine oil inside flows out (0.5-1L per leak), resulting in oil waste, and the leak area needs to be cleaned extra, increasing the workload; 3. Cleanliness and assembly risks: During disassembly and flipping, the cylinder head is easily contaminated with impurities, making it difficult to guarantee cleanliness, which may affect the accuracy of subsequent assembly and the engine's operating performance.

[0003] Therefore, there is an urgent need for a tool that can be used to perform measurements directly on the engine without removing the cylinder head, thus overcoming the drawbacks of traditional methods. Utility Model Content

[0004] This utility model addresses the above-mentioned problems by providing an auxiliary tool for measuring engine valve stem height. Its purpose is to indirectly obtain the valve deflection without disassembling the cylinder head, thereby reducing maintenance time and avoiding oil waste and cylinder head contamination.

[0005] To solve the above problems, the technical solution provided by this utility model is as follows: An auxiliary tool for measuring engine valve stem height includes a main body and bosses located on both sides of the main body; the main body and the bosses are an integral structure; a first circular through hole is provided in the middle of the main body, the position of the first circular through hole corresponds to the injector hole and is used to assist in positioning four valve stems; four second circular through holes are arranged in a cross shape in the four directions of front, back, left and right of the first circular through hole; the positions of the second circular through holes correspond one-to-one with the positions of the four valves on the upper part of the corresponding single cylinder of the engine.

[0006] Preferably, the base material of the auxiliary tool is 45# quenched and tempered steel, which has a hardness of HRC38-HRC42 after quenching treatment, with sharp edges blunted, and the chamfer is 1×45° unless otherwise specified, with a tolerance of ±0.2mm unless otherwise specified.

[0007] Preferably, the upper and lower surfaces of the auxiliary tool are ground to a roughness of Ra0.8μm, and the parallelism of the two planes meets the flatness requirement of 0.04.

[0008] Preferably, the entire surface of the accessory is bluing-treated.

[0009] Preferably, the main body has a total length of 347±0.1mm, a thickness of 12±0.1mm, a front end width of 160±0.1mm, a front end length of 135±0.1mm, and a rear end width of 100±0.1mm; a symmetrical arc-shaped transition structure is provided between the front end and the rear end of the main body; the radius of the arc-shaped transition structure is 80±0.1mm; and a 10mm chamfer is provided at the connection between the arc-shaped transition structure and the rear end of the main body.

[0010] Preferably, the vertical distance between the center of the first circular through hole and the edge of the front end of the main body is 135±0.1mm, which is equal to the vertical distance between the center of the first circular through hole and the left and right sides of the front end of the main body; the centers of the four second circular through holes are distributed on a circle with the center of the first circular through hole as the center and a diameter of 87±0.1mm; the diameter of the second circular through hole is 40±0.1mm.

[0011] Preferably, the thickness of the boss is 20±0.1mm and the height is 50±0.1mm.

[0012] Preferably, the bottom end of the boss has a plurality of rectangular grooves evenly distributed thereon; the grooves are used to increase friction.

[0013] Preferably, the groove is 5mm wide and 4mm deep.

[0014] Preferably, the accessory is suitable for Dongfeng Cummins 15N series engines.

[0015] Compared with the prior art, this utility model has the following advantages: 1. Since the tool of this utility model can indirectly obtain the valve sinking amount without disassembling the cylinder head, the maintenance time is reduced.

[0016] 2. Since the tool of this utility model can indirectly obtain the valve sinking amount without disassembling the cylinder head, it avoids oil waste and cylinder head contamination. Attached Figure Description

[0017] Figure 1 This is a schematic front view of an engine valve stem height measuring tool according to a specific embodiment of the present invention; Figure 2 This is a side view schematic diagram of an engine valve stem height measuring auxiliary device according to a specific embodiment of this utility model; Figure 3This is a top view schematic diagram of an engine valve stem height measuring aid according to a specific embodiment of the present utility model.

[0018] Wherein: 1. Main body, 2. Boss, 1a. First circular through hole, 1b. Second circular through hole, 2a. Groove Detailed Implementation

[0019] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are only for illustrating the present invention and are not intended to limit the scope of the present invention. After reading the present invention, any modifications of the present invention in various equivalent forms by those skilled in the art will fall within the scope defined by the appended claims.

[0020] This utility model application claims protection for an auxiliary device for measuring the height of an engine valve stem, such as... Figure 1 , 2 As shown in Figure 3, the device includes a main body 1 and bosses 2 located on both sides of the main body 1. The main body 1 and the bosses 2 are an integral structure. A first circular through hole 1a is provided in the middle of the main body 1. The position of the first circular through hole 1a corresponds to the injector hole and is used to assist in positioning the four valve stems. Four second circular through holes 1b are arranged in a cross shape in the four directions of front, back, left and right of the first circular through hole 1a. The position of the second circular through hole 1b corresponds one-to-one with the position of the four valves on the upper part of the corresponding single cylinder of the engine and the center distance is completely consistent, ensuring that the valve stems can be accurately inserted into the holes during measurement and avoiding errors caused by positional deviation.

[0021] It should be noted that the base material of the auxiliary fixture is 45# quenched and tempered steel, which has sufficient strength and toughness to withstand installation and measurement operations in the engine compartment and avoid deformation; the whole fixture is quenched, and the hardness after quenching reaches HRC38~HRC42, ensuring that the auxiliary fixture is not easily worn during long-term use and maintains dimensional accuracy; sharp edges are blunted (to prevent scratching operators or parts during installation), and the chamfer is 1×45° unless otherwise specified, and the tolerance is ±0.2mm unless otherwise specified.

[0022] In this specific embodiment, the upper and lower surfaces of the auxiliary tool are ground to a roughness of Ra0.8μm, and the parallelism of the two planes meets the flatness requirement of 0.04.

[0023] It should be further noted that the entire surface of the auxiliary fixture is bluing-treated to improve rust resistance and adapt to the oily environment inside the engine compartment.

[0024] In this specific embodiment, the main body 1 has a total length of 347±0.1mm, a thickness of 12±0.1mm, a front end width of 160±0.1mm, a front end length of 135±0.1mm, and a rear end width of 100±0.1mm (adapting to the mounting surface size of the valve chamber cover); a symmetrical arc-shaped transition structure is provided between the front end and the rear end of the main body; the radius of the arc-shaped transition structure is 80±0.1mm; and a 10mm R10mm chamfer is provided at the connection between the arc-shaped transition structure and the rear end of the main body.

[0025] In this specific embodiment, the vertical distance between the center of the first circular through hole 1a and the edge of the front end of the main body is 135±0.1mm, which is equal to the vertical distance between the center of the first circular through hole 1a and the left and right sides of the front end of the main body; the centers of the four second circular through holes 1b are distributed on a circle with the center of the first circular through hole 1a as the center and a diameter of 87±0.1mm; the diameter of the second circular through hole 1b is 40±0.1mm.

[0026] In this specific embodiment, the thickness of the boss 2 is 20±0.1mm and the height is 50±0.1mm (as a measurement reference surface, the accuracy directly affects the measurement result, so the tolerance is strictly controlled).

[0027] It should be noted that the bottom end of the boss 2 has multiple rectangular grooves 2a evenly distributed; the grooves 2a are used to increase friction.

[0028] In this specific embodiment, the groove 2a is 5mm wide and 4mm deep.

[0029] It should be noted that the auxiliary device is applicable to Dongfeng Cummins 15N series engines.

[0030] It should be noted that the assistive device preparation method of this utility model includes the following steps: Sa1. Blanking: Cut the 45# quenched and tempered steel into rough blanks with a length of 348mm, a width of 161mm, and a height of 51mm (leaving machining allowance).

[0031] Sa2. Rough machining: Mill the rough blank to a length of 347.5±0.2mm, a width of 160.5±0.2mm, and a height of 50.1±0.05mm, and drill 4 pre-holes with a diameter of 39.8±0.1mm; Sa3. Heat treatment: Quench the whole body to HRC38~ HRC42, and then perform low temperature tempering to eliminate internal stress; Sa4. Finishing: Grind the upper and lower surfaces to a height of 50±0.01mm to ensure parallelism ≤0.04mm; ream 4 pre-holes to a diameter of 40±0.1mm to ensure the hole positions match the valve positions; Sa5. Surface treatment: The entire fixture is broached, and then all sharp edges are chamfered (rounded corner R0.5 - 1mm). Unspecified chamfers are processed to 1×45°.

[0032] It should be noted that the measuring principle of the assistive device of this utility model is as follows: The distance (measured value) between the "height reference surface" (top surface) of the auxiliary fixture and the top surface of the valve stem, combined with the height of the auxiliary fixture (50±0.01mm) and the design length of the valve stem itself, is used to indirectly calculate the "valve sinking amount" (the preset standard value is provided by the engine manufacturer, for example, the standard value for a certain model is X±Ymm).

[0033] It should be noted that the operation process of the assistive device of this utility model includes the following steps: Sb1. Pre-treatment: Confirm that the engine is off and there is no high-pressure gas residue in the valve chamber. Remove the valve chamber cover, rocker arm assembly and valve bridge. Clean the valve chamber cover mounting surface with a lint-free cloth to remove oil, metal shavings and other impurities. Sb2. Auxiliary fixture installation: Place the auxiliary fixture stably on the cleaned mounting surface, adjust the position so that the four second circular through holes 1b on the auxiliary fixture are aligned with the four valve stems of the single cylinder, and ensure that the bottom surface of the auxiliary fixture is completely in contact with the mounting surface (without gaps). Sb3. Measurement: Using a depth gauge with an accuracy of not less than 0.01mm, measure the vertical distance from the top surface of the auxiliary tool to the top surface of each valve stem, and record the measured value (measure each valve at least twice and take the average value to reduce error). Sb4. Judgment: Compare the measured value with the preset standard value. If the measured value is within the standard value range, it means that the valve sinking is normal and the valve assembly does not need to be replaced. If it exceeds the standard value, it means that the valve assembly (such as valve wear or seat deformation) has failed and the entire valve assembly needs to be replaced.

[0034] It should be further explained that, taking a certain cylinder of the Dongfeng Cummins 15N engine as an example, the operation process of the auxiliary tool of this utility model includes the following steps: Sc1. Safety preparation: Turn off the main power to the engine, unplug the fuel pump connector, and rotate the crankshaft to bring the cylinder to be measured to the top dead center position (ensure that the valve is fully closed and the valve stem is at its highest position). Sc2. Component disassembly: Use a wrench to remove the fixing bolts (6 in total) of the valve chamber cover and remove the cover; remove the rocker arm shaft bracket bolts, remove the rocker arm assembly and valve bridge, and place them on a clean tooling table; Sc3. Install the auxiliary fixture: Wipe the valve chamber cover mounting surface with isopropyl alcohol and wait for it to dry. Then, gently place the auxiliary fixture on the mounting surface and press the four corners of the auxiliary fixture with your hands to confirm that there is no looseness. Visually inspect to ensure that all four valve stems are inserted into the corresponding second circular through hole 1b of the auxiliary fixture without any offset. Sc4. Depth Measurement: Use a digital depth gauge (accuracy 0.001mm). Place the reference surface of the depth gauge against the top surface of the auxiliary fixture, and slowly bring the probe into contact with the top surface of the valve stem. Record the reading after it stabilizes (for example, the measured value is 28.56mm). Repeat the measurement 3 times for the same valve stem, and the readings are 28.56mm, 28.55mm, and 28.57mm respectively. Take the average value of 28.56mm as the final measurement value. Sc5. Result Judgment: The preset standard value of the valve of this model of Dongfeng Cummins 15N engine is 28.5±0.05mm. The measured average value is 28.56mm, which exceeds the upper limit of the standard. It is determined that the valve assembly is faulty and the valve, valve seat and valve guide need to be replaced.

[0035] In the above detailed description, various features are combined together in a single embodiment to simplify this disclosure. This approach to disclosure should not be construed as reflecting an intention that embodiments of the claimed subject matter require more features than are explicitly stated in each claim. Rather, as reflected in the appended claims, the invention is presented with fewer features than all of the features in a single disclosed embodiment. Therefore, the appended claims are hereby explicitly incorporated into the detailed description, with each claim representing a separate preferred embodiment of the invention.

[0036] The disclosed embodiments have been described above to enable any person skilled in the art to implement or use this invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments without departing from the spirit and scope of this disclosure. Therefore, this disclosure is not limited to the embodiments given herein, but is consistent with the widest scope of the principles and novel features disclosed in this application.

[0037] The foregoing description includes examples of one or more embodiments. It is certainly impossible to describe all possible combinations of components or methods in order to describe the above embodiments, but those skilled in the art will recognize that further combinations and arrangements of the various embodiments are possible. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. Furthermore, the term "comprising" as used in the specification or claims is interpreted in a manner similar to the term "including," as interpreted when used as a conjunction in the claims. Additionally, the use of any term "or" in the specification of the claims is intended to mean "non-exclusive or."

[0038] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. An engine valve stem height measuring aid, characterized by: It includes a main body (1) and bosses (2) located on both sides of the main body (1); the main body (1) and the bosses (2) are an integral structure; a first circular through hole (1a) is provided in the middle of the main body (1), the position of the first circular through hole (1a) corresponds to the injector hole and is used to assist in positioning the four valve stems; four second circular through holes (1b) are arranged in a cross shape in the four directions of front, back, left and right of the first circular through hole (1a); the position of the second circular through hole (1b) corresponds one-to-one with the position of the four valves on the upper part of the corresponding single cylinder of the engine.

2. The engine valve stem height measuring aid of claim 1, wherein: The base material of the auxiliary tool is 45# quenched and tempered steel, which has a hardness of HRC38~HRC42 after quenching treatment. The sharp edges are blunted, and the chamfer is 1×45° unless otherwise specified. The tolerance is ±0.2mm unless otherwise specified.

3. The engine valve stem height measuring aid of claim 2, wherein: The upper and lower surfaces of the auxiliary tool are ground to a roughness of Ra0.8μm, and the parallelism of the two planes meets the flatness requirement of 0.

04.

4. The engine valve stem height measuring aid of claim 3, wherein: The entire surface of the accessory is bluing-treated.

5. The engine valve stem height measuring device according to claim 4, characterized in that: The main body (1) has a total length of 347±0.1mm, a thickness of 12±0.1mm, a front end width of 160±0.1mm, a front end length of 135±0.1mm, and a rear end width of 100±0.1mm. A symmetrical arc-shaped transition structure is provided between the front end and the rear end of the main body. The radius of the arc-shaped transition structure is 80±0.1mm. A 10mm chamfer is provided at the connection between the arc-shaped transition structure and the rear end of the main body.

6. The engine valve stem height measuring aid of claim 5, wherein: The vertical distance between the center of the first circular through hole (1a) and the edge of the front end of the main body is 135±0.1mm, which is equal to the vertical distance between the left and right sides of the front end of the main body; the centers of the four second circular through holes (1b) are distributed on a circle with the center of the first circular through hole (1a) as the center and a diameter of 87±0.1mm; the diameter of the second circular through hole (1b) is 40±0.1mm.

7. The engine valve stem height measuring device according to claim 6, characterized in that: The thickness of the boss (2) is 20±0.1mm and the height is 50±0.1mm.

8. The engine valve stem height measuring aid of claim 7, wherein: The bottom end of the boss (2) is evenly distributed with multiple rectangular grooves (2a); the grooves (2a) are used to increase friction.

9. The engine valve stem height measuring aid of claim 8, wherein: The groove (2a) is 5mm wide and 4mm deep.

10. The engine valve stem height measuring device according to claim 9, characterized in that: The auxiliary device is applicable to Dongfeng Cummins 15N series engines.

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