A machining method for a pump body of a high-pressure oil delivery pump

Abstract

The application provides a high-pressure oil delivery pump body machining method, comprising the following steps: rough milling and planing the bottom end face of the pump body and the adjusting screw end face to a certain machining allowance from the finished product size; taking the rough milling and planed bottom end face of the pump body as the bottom reference, and taking the rough milling and planed adjusting screw end face as the side reference to keep parallel with the machine tool transverse X axis, and rough machining the camshaft hole orifices on both sides of the pump body. The high-pressure oil delivery pump body machining method can be applied to the machining of the in-line high-pressure oil delivery pump body, the machining scheme of the high-pressure oil delivery pump with the structure is optimized and integrated, the integrated and combined processes are realized while the product process technical requirements are ensured, the machining processes are reduced, the repeated positioning precision deviation accumulation caused by repeated clamping between processes is reduced, and the machining precision and production efficiency of the pump body are improved.

Description

Technical Field

[0001] This invention belongs to the field of engine technology, and in particular relates to a method for processing a high-pressure oil pump body. Background Technology

[0002] The high-pressure oil pump body is a straight-flow multi-cylinder oil pump body. This component is one of the most critical components in the engine. It meets the requirements of high temperature and high pressure during engine operation, and at the same time provides the engine with a stable oil supply. Moreover, this component is a typical straight-flow multi-cylinder high-pressure oil pump, which has complex design features such as complex structure, compact size, and high cylinder bore precision.

[0003] Because this component is a critical load-bearing component in the engine, it has many connecting parts in various directions and angles, and the dimensional accuracy requirements are high. In order to ensure the machining dimensions, the existing high-pressure oil pump machining method often adopts multi-process machining in a single angle direction. The machining process is long, and the dimensions of the previous process are used as the reference between each process. Since the positioning reference during machining and clamping is a clearance fit, the cumulative error becomes larger and larger, and the product machining consistency cannot be controlled. Critical dimensional errors may occur, such as the axis dimensions of the cylinder plunger hole and the camshaft hole are not the same or the axis is misaligned, the two ends of the measuring rod hole on both sides of the pump body are not the same, or the two sides are misaligned in the sub-processing. This leads to low machining accuracy, long time for repeated positioning adjustment between processes, a large number of fixtures and long preparation time, and a large number of equipment involved. As a result, the machining dimensions and geometric tolerances cannot be guaranteed, the product qualification rate is low, the production process is slow and production schedules are delayed. Summary of the Invention

[0004] In view of this, the present invention aims to propose a method for processing the pump body of a high-pressure oil pump, so as to solve the problems of low processing accuracy, repeated positioning adjustments, and the impact on product qualification rate and production efficiency of existing high-pressure oil pump processing methods.

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

[0006] A method for machining a high-pressure oil pump body includes:

[0007] The bottom surface of the pump body and the end face of the adjusting screw are rough milled to leave a certain machining allowance from the finished size;

[0008] The bottom surface of the pump body after rough milling is used as the bottom reference, and the end face of the adjusting screw after rough milling is used as the side reference to align with the machine tool's transverse X-axis. The camshaft holes on both sides of the pump body are rough-machined, and a certain machining allowance is reserved between the hole diameter and the finished size.

[0009] Using the camshaft holes on both sides of the roughly machined pump body as positioning pin holes, and the end face of the adjusting screw after rough milling as the bottom plane reference, the ruler holes on both sides of the pump body are machined to the finished size;

[0010] Rotate the worktable on the machine tool and machine the cylinder plunger hole and top surface of the pump body to the finished size;

[0011] The top surface of the processed pump body is re-established as the bottom plane reference, and the cylinder plunger holes at both ends of the processed pump body are used as positioning pin holes. The two end faces of the pump body ruler hole, the end face of the pump body adjusting screw, and the camshaft hole are then precision machined.

[0012] Furthermore, after rough milling the bottom surface of the pump body and the end face of the adjusting screw to allow for a certain machining allowance from the finished size, the method further includes:

[0013] The perpendicularity tolerance of the bottom end face of the pump body and the end face of the adjusting screw is controlled within ±0.05 mm.

[0014] Furthermore, the machining allowance is at least 0.5 mm.

[0015] Furthermore, after using the bottom end face of the pump body after rough milling as the bottom reference and the end face of the adjusting screw after rough milling as the side reference to align with the machine tool's transverse X-axis, and performing rough machining on the camshaft holes on both sides of the pump body, leaving a certain machining allowance between the machined hole diameter and the finished size, the method further includes:

[0016] The positional tolerance of the camshaft holes on both sides of the pump body is controlled within ±0.03 mm, and the coaxiality is controlled within ±0.05 mm.

[0017] Furthermore, the top surface of the machined pump body is re-established as the bottom plane reference, and the cylinder plunger holes at both ends of the machined pump body are used as positioning pin holes. The two end faces of the pump body ruler hole, the end face of the pump body adjusting screw, and the camshaft hole are then precision machined to obtain the finished pump body, including:

[0018] The top surface of the processed pump body is used as the bottom plane reference, and the cylinder plunger holes at both ends of the processed pump body are used as positioning pin holes.

[0019] Using the rotary table of a CNC machine, the two end faces of the pump body rod hole, the end face of the pump body adjusting screw, and the camshaft hole are rotated and precision machined to obtain the finished pump body.

[0020] Compared with the prior art, the high-pressure oil pump body processing method of the present invention has the following advantages:

[0021] The high-pressure oil pump body machining method described in this invention is applicable to the machining of inline high-pressure oil pump bodies. By optimizing and integrating the machining scheme for this type of high-pressure oil pump, while ensuring product process requirements, it integrates and merges processes, reduces machining steps, and minimizes the cumulative repetitive positioning accuracy deviations caused by repeated clamping between processes. This is beneficial for improving the machining accuracy and production efficiency of the pump body. Furthermore, by processing multiple processes into four processes, and utilizing the positioning of the cylinder plunger hole in the key part to complete the machining of related key parts in one go, it ensures the accuracy of the machining dimensions of each position and the associated dimensions of the cylinder plunger hole, eliminates repetitive positioning errors between multiple processes, effectively guarantees the part's machining pass rate, reduces process arrangement, lowers product scrap rate, and helps ensure high-quality production of the pump body. Attached Figure Description

[0022] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0023] Figure 1 This is a schematic diagram of a high-pressure oil pump body processing method according to an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the pump body structure in a high-pressure oil pump body processing method according to an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the camshaft hole in a high-pressure oil pump body machining method according to an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the structure at the ruler hole in a high-pressure oil pump body processing method according to an embodiment of the present invention. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0028] This invention provides a method for machining a high-pressure oil pump body, such as... Figures 1 to 4 As shown, this processing method specifically includes the following steps:

[0029] Step 101: Roughly mill the bottom face of the pump body and the end face of the adjusting screw until a certain machining allowance is reserved from the finished size, and ensure that the perpendicularity tolerance is within ±0.05 mm. The machining allowance is at least 0.5 mm. Those skilled in the art can also adjust the machining allowance appropriately according to actual needs, which will not be elaborated here.

[0030] Step 102: Using the bottom surface of the pump body after rough milling as the bottom reference, and the end face of the adjusting screw after rough milling as the side reference, align it parallel to the transverse X-axis of the machine tool. Roughly machine the camshaft holes on both sides of the pump body, leaving a certain machining allowance between the machined hole diameter and the finished size. The machining allowance is at least 0.5 mm. Those skilled in the art can adjust the machining allowance according to actual needs, which will not be elaborated here.

[0031] Step 103: Using the camshaft holes on both sides of the roughly machined pump body as positioning pin holes, and using the end face of the adjusting screw after rough milling as the bottom plane reference, process the ruler holes on both sides of the pump body to the finished size.

[0032] Step 104: Rotate the worktable on the machine tool and machine the cylinder plunger hole and top surface of the pump body to the finished size.

[0033] Step 105: Re-establish the bottom plane reference by facing down on the top surface of the processed pump body, and use the cylinder plunger holes at both ends of the processed pump body as positioning pin holes to perform precision machining on the two end faces of the pump body rod hole, the end face of the pump body adjusting screw, and the camshaft hole.

[0034] The processing method described in this embodiment can perform concentrated processing of the pump body of this type of inline high-pressure oil pump to the greatest extent, effectively eliminating the repeated positioning errors caused by repeated positioning between multiple processes, as well as the alignment errors between processes. For key processing dimensions, processing can be completed in one clamping. The dimensional and positional accuracy of the cylinder plunger hole and camshaft hole is improved to 0.02 mm in one operation, and the processing dimensions of the ruler hole and other surrounding dimensions are improved to within ±0.05 mm. This ensures product quality, improves processing efficiency, reduces the production cost of multiple sets of fixtures, ensures the progress of scientific research and production, and improves the consistency of the finished pump body dimensions. In addition, this processing method significantly improves the product qualification rate, eliminates the preparation time between processes, significantly shortens the processing time of a single product, and improves the production efficiency of the pump body.

[0035] Optionally, after using the bottom end face of the pump body after rough milling as the bottom reference and the end face of the adjusting screw after rough milling as the side reference to align with the machine tool's transverse X-axis, and after rough machining the camshaft holes on both sides of the pump body, leaving a certain machining allowance between the machined hole diameter and the finished size, the method further includes:

[0036] The positional tolerance of the camshaft hole openings on both sides of the pump body is controlled within ±0.03 mm, and the coaxiality is controlled within ±0.05 mm. Controlling the positional tolerance of the camshaft hole openings on both sides of the pump body within ±0.03 mm and the coaxiality within ±0.05 mm facilitates accurate subsequent positioning and ensures the machining accuracy of other parts of the pump body.

[0037] Optionally, the top surface of the machined pump body is re-established as the bottom plane reference, and the cylinder plunger holes at both ends of the machined pump body are used as locating pin holes. The two end faces of the pump body ruler hole, the end face of the pump body adjusting screw, and the camshaft hole are then precision machined to obtain the finished pump body, including:

[0038] First, the top surface of the processed pump body is used as the bottom plane reference, and the cylinder plunger holes at both ends of the processed pump body are used as positioning pin holes.

[0039] Secondly, using the rotary table of the CNC machine, the two end faces of the pump body's measuring rod hole, the end face of the pump body's adjusting screw, and the camshaft hole are precision machined in one rotation, resulting in a finished pump body. By using the rotary table of the CNC machine, the pump body can be rotated. One rotation completes the precision machining of the two end faces of the pump body's measuring rod hole, the end face of the pump body's adjusting screw, and the camshaft hole, ensuring that these parts are machined to the finished dimensions without the need for repositioning, reducing the possibility of machining errors and improving machining efficiency.

[0040] In practical applications, those skilled in the art can also analyze the shape and dimensions of the pump body to be machined and use this machining method to ensure that the machining accuracy of the key dimensions of the pump body meets the accuracy requirements. The machining method described in this embodiment adopts a new process-integrated machining method, which integrates the machining processes for key dimensions, shortens the machining process as much as possible, and reduces the accuracy errors caused by repeated clamping and positioning between processes.

[0041] Specifically, such as Figures 2 to 4 As shown, the following steps are explained in conjunction with the actual pump body structure:

[0042] 1. First, rough mill the bottom face (⑦) and the end face of the adjusting screw (⑥) until a 0.5 mm allowance is left between the finished product dimensions, ensuring that the perpendicularity tolerance is within ±0.05 mm.

[0043] 2. Using the bottom face of ⑦ as the bottom reference and the end face of the adjusting screw of ⑥ as the side reference, align the machine tool with the transverse X-axis. Roughly machine the openings of the camshaft holes on both sides ②, leaving a 0.5 mm allowance between the machined hole diameter and the finished size. Control the positional tolerance of the holes at both ends within ±0.03 mm and their coaxiality within ±0.05 mm.

[0044] 3. Using the camshaft holes ② after machining on both sides as locating pin holes and the end face of the adjusting screw ⑥ as the bottom plane reference, machine the dimensions of the rod holes ③ and ④ on both sides of the pump body to the finished dimensions. Then rotate the worktable to machine the cylinder plunger hole ① and the top surface ⑤ to the finished dimensions.

[0045] 4. Using the top face of ⑤ facing down as the bottom plane reference, and using the cylinder plunger holes of the left and right ends ① as positioning pin holes, and using the rotary table of the CNC equipment, perform precision machining on the two end faces of the ③ and ④ ruler holes, the end face of the ⑥ adjusting screw, and the ② camshaft hole in all directions, so as to complete the machining of the pump body in one go.

[0046] The high-pressure oil pump body machining method described in this invention is applicable to the machining of inline high-pressure oil pump bodies. By optimizing and integrating the machining scheme for this type of high-pressure oil pump, the method integrates and merges processes while ensuring product process requirements, reducing machining steps and minimizing the cumulative repetitive positioning accuracy deviations caused by repeated clamping between processes. This improves the machining accuracy and production efficiency of the pump body. Furthermore, by processing multiple processes into four steps, and utilizing the positioning of the cylinder plunger hole in the key part to complete the machining of related critical parts in one operation, the method ensures the accuracy of the machining dimensions at each position and the associated dimensions of the cylinder plunger hole. This eliminates repetitive positioning errors between multiple processes, effectively ensuring the part's pass rate, reducing process arrangements, lowering the product scrap rate, and contributing to high-quality pump body production.

[0047] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A method for processing a high-pressure oil pump body, characterized in that, include: The bottom surface of the pump body and the end face of the adjusting screw are rough milled to leave a certain machining allowance from the finished size; The bottom surface of the pump body after rough milling is used as the bottom reference, and the end face of the adjusting screw after rough milling is used as the side reference to align with the machine tool's transverse X-axis. The camshaft holes on both sides of the pump body are rough-machined, and a certain machining allowance is reserved between the hole diameter and the finished size. Using the camshaft holes on both sides of the roughly machined pump body as positioning pin holes, and the end face of the adjusting screw after rough milling as the bottom plane reference, the ruler holes on both sides of the pump body are machined to the finished size; Rotate the worktable on the machine tool and machine the cylinder plunger hole and top surface of the pump body to the finished size; The top surface of the processed pump body is re-established as the bottom plane reference, and the cylinder plunger holes at both ends of the processed pump body are used as positioning pin holes. The two end faces of the pump body ruler hole, the end face of the pump body adjusting screw, and the camshaft hole are precision machined. After using the bottom end face of the pump body after rough milling as the bottom reference and the end face of the adjusting screw after rough milling as the side reference to align with the machine tool's transverse X-axis, and performing rough machining on the camshaft holes on both sides of the pump body, leaving a certain machining allowance between the machined hole diameter and the finished size, the method further includes: The positional tolerance of the camshaft holes on both sides of the pump body is controlled within ±0.03 mm, and the coaxiality is controlled within ±0.05 mm.

2. The method for processing a high-pressure oil pump body according to claim 1, characterized in that, After rough milling the bottom surface of the pump body and the end face of the adjusting screw to allow for a certain machining allowance from the finished size, the method further includes: The perpendicularity tolerance of the bottom end face of the pump body and the end face of the adjusting screw is controlled within ±0.05 mm.

3. A method for processing a high-pressure oil pump body according to claim 1 or 2, characterized in that: The machining allowance is at least 0.5 mm.

4. The method for processing a high-pressure oil pump body according to claim 1, characterized in that, The process involves re-machining the top surface of the processed pump body downwards as the bottom plane reference, and using the cylinder plunger holes at both ends of the processed pump body as locating pin holes. The two end faces of the pump body's measuring rod hole, the end face of the pump body's adjusting screw, and the camshaft hole are then precision-machined to obtain the finished pump body, including: The top surface of the processed pump body is used as the bottom plane reference, and the cylinder plunger holes at both ends of the processed pump body are used as positioning pin holes. Using the rotary table of a CNC machine, the two end faces of the pump body rod hole, the end face of the pump body adjusting screw, and the camshaft hole are rotated and precision machined to obtain the finished pump body.

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