A high-bearing motor cylinder hole strengthening polishing device and process method

Abstract

The application provides a kind of high bearing motor cylinder hole strengthening polishing device and process method, mainly aiming at the strengthening polishing processing of cylinder copper alloy hole, improve the wear resistance and surface roughness of cylinder hole.The application is designed to make cylinder polishing cutter, jade strip is inlaid on the cutter, to realize the need of strengthening polishing.Two is through new process method to carry out pretreatment before polishing, so that copper alloy surface forms a kind of wear-resistant composite structure layer, finally uses jade strip to flatten and polish the composite structure layer, under the action of extrusion force, makes copper alloy composite layer plastic deformation, improves the roughness and cylindricity of copper alloy and surface strength, reaches the good wear resistance and service life of high bearing friction pair.

Description

Technical Field

[0001] This invention belongs to the field of surface engineering technology of materials, and specifically relates to a strengthening polishing device and process method for high load-bearing motor cylinder bores. Background Technology

[0002] Existing technology utilizes high-precision five-axis machining centers to machine cylinder bores, achieving a cylindricity of 0.003-0.005 mm and Ra of 0.2-0.4 μm. Further precision honing further improves the cylindricity to 0.0015-0.002 mm and Ra to 0.1-0.2 μm.

[0003] Because this high-load motor operates at pressures of 28MPa-35MPa and speeds of 8000-12000rpm, abnormal wear occurs in the cylinder bore clearance under high-pressure, high-speed, and high-load conditions. This leads to increased clearance, increased internal leakage, and a decrease in volumetric efficiency. Therefore, to address these high-pressure, high-speed operating conditions, it is necessary to improve the wear resistance and lifespan of the high-load motor's cylinder bore.

[0004] Existing machining processes cannot meet the requirements of high speed and high load technology for the machining accuracy and surface wear resistance of motor cylinder bores. This results in large gaps and abnormal wear in the motor cylinder bores during operation, which in turn leads to problems such as internal leakage and reduced volumetric efficiency. Summary of the Invention

[0005] This invention proposes a polishing device and process for strengthening the bore of a high-load motor cylinder, which solves the problem that existing processing methods cannot meet the technical requirements of high speed and high load.

[0006] The first aspect of this invention provides a strengthening and polishing device for a high-load-bearing motor cylinder bore, comprising: an internally expanding cone 1, a keyway 2, an external thread 3 and a pin hole 4, a jade polishing sleeve 5, a jade strip 6, and a grinding sleeve 9; wherein, The internal expansion cone 1 includes a tool holder and a cone head. The tool holder is located at the end of the cone head with a smaller outer diameter, and the cone head is provided with a keyway 2 along the axial direction. The grinding sleeve 9 is an inner tapered type, with straight slots and multiple through slots on the outer circular side. The straight slots are used for key connection with the keyway 2, and the through slots are used to make it easy to expand. The grinding sleeve 9 is used for applying grinding slurry and embedding abrasive in the grinding slurry before polishing the high load-bearing motor cylinder bore. The jade polishing sleeve 5 is an inner tapered type, with straight grooves, multiple jade inlay grooves and multiple through grooves on the outer circular side. Jade strips 6 are inlaid in the jade inlay grooves. The jade polishing sleeve 5 is used to strengthen the polishing of the high load-bearing motor cylinder hole to form a dense composite surface.

[0007] Optionally, the grinding fluid is obtained by mixing silicon carbide abrasive with a particle size of 2-3.5 micrometers, HH20 high-viscosity lubricating oil, and RP-3 aviation kerosene in a ratio of 1:1:1.

[0008] Optionally, when using the jade polishing sleeve 5 for enhanced polishing, the gap between the inner hole of the high-load motor cylinder and the jade strip 6 on the jade polishing sleeve 5 is kept at 0-0.005mm, the rotation speed of the jade polishing sleeve 5 is 40-60mm / min, the reciprocating speed of the jade polishing sleeve 5 is 5-10mm / min, and 2-3 cycles are performed.

[0009] Optionally, when using the grinding sleeve 9 for abrasive embedding, the cylindrical surface gap between the inner hole of the high-load motor cylinder and the grinding sleeve 9 is 0.008-0.012 mm, the unit pressure is 0.001-0.01 MPa, and the reciprocating speed of the grinding sleeve 9 is 0.1-0.5 m / s.

[0010] Optionally, the outer circumference of the jade polishing kit 5 is provided with a straight groove and three through grooves, which are evenly arranged.

[0011] Optional, the high-load motor cylinder bore strengthening and polishing device also includes: jade correction sleeve 12; Jade correction kit 12 includes: outer sleeve 13 and inner sleeve 14; The inner sleeve 14 is provided with a straight slot, and the outer sleeve 13 is provided with multiple set screw holes 15; The outer sleeve 13 clamps the inner sleeve 14 by a plurality of set screws inserted into the set screw holes 15; The inner sleeve 14 is set on the outside of the jade polishing sleeve 5 and is used to modify the jade polishing sleeve 5.

[0012] Optionally, the taper of the cone head is 1:50.

[0013] Optional, the high-load motor cylinder bore strengthening and polishing device also includes: tensioning sleeve 10; The tensioning sleeve 10 is provided with a hexagonal screw hole 11; The handle is provided with an external thread 3, and the tensioning sleeve 10 is threadedly connected to the external thread 3. By rotating, it pushes the jade polishing sleeve 5 or the grinding sleeve 9 to move on the cone head. The position of the tensioning sleeve 10 on the tool holder is fixed by a screw located in the hexagonal screw hole 11.

[0014] Optionally, the tool holder is provided with a pin hole 4; The pin hole 4 is used to insert the handle to rotate the strengthening polishing device.

[0015] A second aspect of the present invention also provides a method for strengthening polishing a high-load motor cylinder bore using a strengthening polishing apparatus as described in any one of the first aspects, comprising: Install the grinding sleeve 9 on the cone head, apply the grinding fluid to the grinding sleeve 9, and move the high load motor cylinder and the grinding sleeve 9 relative to each other to achieve the application of grinding fluid and the embedding of abrasive in the grinding fluid before polishing the high load motor cylinder hole. Remove the grinding sleeve 9 from the cone head and install the jade polishing sleeve 5 on the cone head to perform enhanced polishing on the high load-bearing motor cylinder bore to form a dense composite surface.

[0016] This invention proposes a polishing device and process for enhancing the polishing of high-load-bearing motor cylinder bores. It primarily targets the copper alloy bores in the cylinder block for enhanced polishing, improving their wear resistance and surface roughness. The invention involves two main aspects: First, designing and manufacturing a polishing tool for the cylinder block, inlaying jade strips onto the tool to achieve the desired enhanced polishing. Second, employing a novel pretreatment process before polishing; this creates a wear-resistant composite layer on the copper alloy surface. Finally, the jade strips are used to flatten and polish this composite layer, causing plastic deformation under pressure. This improves the roughness, cylindricity, and surface strength of the copper alloy, resulting in excellent wear resistance and extended service life for the high-load-bearing friction pair. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the high-load-bearing motor cylinder bore strengthening and polishing device of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of the high-load-bearing motor cylinder bore strengthening and polishing device of the present invention. Figure 2 ; Figure 3 A schematic diagram of the structure of a jade polishing kit; Figure 4 This is a schematic diagram of the grinding sleeve structure; Figure 5 This is a schematic diagram of the internal expansion cone structure; Figure 6 Schematic diagram of the structure of jade correction tool Figure 1 ; Figure 7 Schematic diagram of the structure of jade correction tool Figure 2 ; Figure 8 Schematic diagram of the tensioning sleeve structure Figure 1 ; Figure 9 Schematic diagram of the tensioning sleeve structure Figure 2 ; Figure 10 Schematic diagram of the tensioning sleeve structure Figure 3 ; Explanation of reference numerals in the attached figures: 1-Internal expansion cone; 2-Keyway; 3-External thread; 4-Pin holes; 5-Jade polishing kit; 6-Jade strip; 7-Through groove; 8-Straight slot; 9-Grinding sleeve; 10-Tightening of the loopholes; 11- Hexagonal screw hole; 12-Jade Correction Kit; 13-Outerwear; 14-Inner sleeve; 15 - Top screw hole. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] The features and illustrative embodiments of various aspects of the present invention will now be described in detail. Numerous specific details are set forth in the following detailed description to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific setups and methods set forth below, but covers any improvements, substitutions, and modifications to structures, methods, and devices without departing from the spirit of the invention. Well-known structures and techniques are not shown in the drawings and the following description to avoid unnecessarily obscuring the invention.

[0020] In the description of this invention, it should be noted that the directions or positional relationships indicated by terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing and simplifying the invention, and should not be construed as limiting the invention. Furthermore, the use of ordinal numbers (e.g., "first and second," etc.) is for distinguishing objects and is not limited to this order, and should not be construed as indicating or implying relative importance.

[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly, encompassing both direct connection and indirect connection via an intermediate medium. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0022] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other, and the various embodiments can be referenced and cited in each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0024] like Figure 1-10 As shown, this invention proposes a polishing device and process for strengthening the bore of a high-load motor cylinder.

[0025] This invention takes into account the high-pressure, high-speed friction conditions of the cylinder bore of a high-load motor, which requires continuous improvement of the surface characteristics of the cylinder bore and plunger to make the surface of the friction pair material more wear-resistant. This can be achieved by improving the fatigue strength of the contact surface and extending the safe service life.

[0026] Surface strengthening can improve the properties of the contact surfaces of friction pairs and is a process method to improve fatigue strength and wear resistance. This invention achieves this technical bottleneck by designing and manufacturing jade polishing tools and employing a new process method to strengthen the polishing of cylinder bores. The specific solution is as follows; a. Pre-processing before polishing By designing grinding tools and moving parts and grinding tools relative to each other, a thin layer of suspended abrasive grains is frictionally embedded in the inner wall of the cylinder bore. The resulting metal surface roughness Ra is 0.2-0.30 μm; cylindricity is 0.002-0.0025 mm; and the size is reduced by 0.0005-0.001 mm compared to the original size, resulting in a uniform, matte surface with a light gray background.

[0027] b. Jade Enhancement Polishing By designing a jade polishing sleeve on an internally expanding conical tool and using a jade strip polishing tool to enhance the polishing of the inner wall of the cylinder bore, the high density and high hardness of jade are utilized. Through reciprocating movement and rotation, the abrasive grains embedded in the inner wall of the bore are forced into the copper alloy surface, forming a surface composite layer. The surface roughness value can be improved from the original Ra0.2-0.30μm to Ra0.08-0.1μm; the cylindricity is improved from 0.002-0.0025mm to 0.001-0.0008mm, and the dimensions are increased by 0.0005-0.001mm compared to the original dimensions. This further improves the accuracy of the cylinder bore and forms a bright surface.

[0028] The internal expansion cone 1 consists of a fine-tooth external thread 3 on the shank, a keyway 2 on the head, and a pin hole 4.

[0029] The tensioning sleeve 10 has an internal thread and an outer hexagonal hole 11. The tensioning sleeve 10 is used to adjust the expansion degree of the jade polishing sleeve 5.

[0030] The jade polishing sleeve 5 is internally tapered, with a groove on its outer circumference for inlaying jade strips 6, which are evenly placed at 90-degree angles around the circumference. Three through grooves 7 are provided on the side of the jade strips 6 to facilitate expansion. Straight grooves 8 are provided in the jade polishing sleeve 5.

[0031] The jade correction sleeve 12 consists of an inner sleeve 14 and an outer sleeve 13. The outer sleeve 13 is clamped to the inner sleeve 14 by three set screws passing through the set screw holes 15. This is used to correct the jade polishing sleeve 5 and meet the requirements of the jade strengthening process.

[0032] The ductile iron grinding sleeve 9 has a similar structure to the jade polishing sleeve 5, but it does not have a jade strip inlaid. Its outer diameter is the same as that of the jade polishing sleeve 5, which has a jade strip inlaid.

[0033] For example, a jade polishing sleeve 5 is installed on the head of the internal expansion cone 1. The straight groove 8 on the jade polishing sleeve 5 coincides with the keyway 2 on the head of the internal expansion cone 1, and they are connected by a key. The external thread 3 on the shank of the internal expansion cone 1 is connected to the internal thread of the tensioning sleeve 10. The tensioning sleeve 10 is provided with an internal hexagonal groove 11. By rotating the tensioning sleeve 10, the jade polishing sleeve 5 is pushed to expand. The jade strip 6 embedded in the jade polishing sleeve 5 contacts the cylinder hole, and the polishing function is enhanced under the action of compressive stress and reciprocating rotational force.

[0034] The process is as follows: 1) The processing flow before cylinder polishing is as follows: Use silicon carbide abrasive with a particle size of 2-3.5 micrometers, HH20 high viscosity lubricating oil and RP-3 aviation kerosene to mix and stir evenly in a ratio of 1:1:1, and adjust the grinding fluid into a viscous liquid.

[0035] 2) Apply the abrasive slurry to the ductile iron abrasive tool and grind the parts by moving them relative to each other. This completes the abrasive application before polishing.

[0036] 3) To achieve the required surface quality, the gap between the machined surface and the grinding tool should be 0.015-0.01 mm. The unit pressure should be 0.001-0.01 MPa. To ensure the surface quality of the parts, the reciprocating and rotating movements should be straight, moving horizontally at a speed of 0.1-0.5 mm / s without preload. Visual inspection result: a uniform, matte surface with a light gray background.

[0037] 4) Then, proceed with the enhanced polishing process: The cylinder is fixed stably on the fixture, and the jade polishing sleeve is installed on the internal expansion cone, with a tensioning sleeve attached, forming a single unit. It is then connected to the machine tool spindle. The tightness between the jade polishing sleeve and the cylinder bore is adjusted by rotating the tensioning sleeve, ensuring close contact between the jade polishing sleeve and the product's inner bore. Maintain a gap of 0-0.005mm between the inner bore and the jade polishing sleeve. The low speed is 40-60mm / min, and the reciprocating speed is 5-10mm / min, with 2-3 cycles per cycle. The jade polishing sleeve moves linearly, reciprocatingly, and rotary within the cylinder bore, requiring 2-3 cycles per bore. The inner bore of the cylinder is cleaned with a cleaning agent and wiped with a clean silk cloth; the inner bore becomes shiny. Enhanced polishing is complete. After using the jade polishing sleeve, the black residue on the jade surface is cleaned with gasoline, wiped dry with a silk cloth, and then the next part is processed.

[0038] Natural jade can be fixed using solid adhesives. Natural jade used includes both jadeite and nephrite. The selection of jade includes: Hetian jade (including jadeite and nephrite), jadeite, Dushan jade, uranium rock jade, agate, lapis lazuli, and crystal.

[0039] The jade strips are rectangular in shape, with a rounded polished surface. Before polishing, the jade needs to undergo external grinding to ensure the polishing bushing has the same diameter as the hole being processed. The jade should be cleaned with gasoline or GLQ-037 cleaning agent before and after polishing.

[0040] The method provided by this invention can further improve the machining accuracy of the motor cylinder bore and the wear resistance of the inner bore, and improve the roughness and cylindricity of the copper alloy, mainly in the following aspects.

[0041] 1. The jade polishing fixture adopts a split, internally expanding structure, which allows for fine adjustment of the tightening degree and maintains the uniformity of the jade polishing sleeve when it opens. The cutting tools simultaneously meet both mechanical and manual functions.

[0042] 3. The suspension grinding process using silicon carbide abrasive coated on ductile iron grinding sleeves can make the abrasive uniformly embedded on the inner surface of the copper alloy cylinder. Due to the high carrier mobility of silicon carbide molecules, during contact with metal and grinding and polishing, silicon carbide has high electron and hole mobility. During contact with metal and grinding and polishing, it is easy to combine with metal molecules to form a composite structure with high bonding rate and is not easy to fall off.

[0043] 4. Due to the density and high hardness of jade, the uniformity of the material, and the low surface roughness of jade, the surface of the copper alloy and silicon carbide composite material can form a dense composite structure and a low roughness value under compressive stress during the polishing process.

[0044] 5. Jade is a silicate mineral, mainly composed of silicon dioxide and magnesite. It is a natural crystal formed under high temperature and pressure from lava. It is a physically and chemically stable and wear-resistant material with excellent heat dissipation and is not easily deformed. It is a high-end material for making polishing tools, resulting in more stable and durable tools.

[0045] 6. Improve the surface characteristics of the cylinder bore, enhance the fatigue strength of its contact surface, increase wear resistance and extend service life.

[0046] The above description merely illustrates the embodiments of this application, and while it is quite specific and detailed, it should not be construed as limiting the scope of the patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Furthermore, any parts not detailed in this application are conventional techniques.

Claims

1. A device for strengthening and polishing high-load-bearing motor cylinder bores, characterized in that, include: Internal expansion taper (1), keyway (2), external thread (3) and pin hole (4), jade polishing sleeve (5), jade strip (6), grinding sleeve (9); among which, The internal expansion cone (1) includes a tool holder and a cone head. The tool holder is located at the end of the cone head with a smaller outer diameter, and the cone head is provided with a keyway (2) along the axial direction. The grinding sleeve (9) is an inner tapered type, with a straight slot and multiple through slots on the outer circular side. The straight slot is used to make key connection with the keyway (2), and the through slots are used to make it easy to expand. The grinding sleeve (9) is used to apply grinding fluid and embed abrasive in the grinding fluid before polishing the high load motor cylinder hole. The jade polishing sleeve (5) is an inner tapered type, with a straight groove, multiple jade inlay grooves and multiple through grooves on the outer circular side. Jade strips (6) are inlaid in the jade inlay grooves. The jade polishing sleeve (5) is used to strengthen the polishing of the high load-bearing motor cylinder hole to form a dense composite surface. The grinding fluid is prepared by mixing silicon carbide abrasive with a particle size of 2-3.5 micrometers, HH20 high-viscosity lubricating oil, and RP-3 aviation kerosene in a ratio of 1:1:

1. When using the jade polishing sleeve (5) for enhanced polishing, the gap between the inner hole of the high load motor cylinder and the jade strip (6) on the jade polishing sleeve (5) is kept at 0-0.005mm, the rotation speed of the jade polishing sleeve (5) is 40-60mm / min, the reciprocating speed of the jade polishing sleeve (5) is 5-10mm / min, and the cycle processing is carried out for 2-3 strokes.

2. The high-load-bearing motor cylinder bore strengthening and polishing device according to claim 1, characterized in that, When using the grinding sleeve (9) for abrasive embedding, the cylindrical surface gap between the inner hole of the high load motor cylinder and the grinding sleeve (9) is 0.008-0.012 mm, the unit pressure is 0.001-0.01 MPa, and the reciprocating speed of the grinding sleeve (9) is 0.1-0.5 m / s.

3. The enhanced polishing device for high load-bearing motor cylinder bores according to claim 1, characterized in that, The outer circumference of the jade polishing kit (5) is provided with a straight groove and three through grooves, which are evenly arranged.

4. The enhanced polishing device for high load-bearing motor cylinder bores according to claim 1, characterized in that, Also includes: Jade correction kit (12); The jade correction kit (12) includes: an outer sleeve (13) and an inner sleeve (14); The inner sleeve (14) is provided with a straight slot, and the outer sleeve (13) is provided with multiple set screw holes (15). The outer sleeve (13) clamps the inner sleeve (14) by multiple set screws inserted into the set screw holes (15); The inner sleeve (14) is fitted on the outside of the jade polishing sleeve (5) and is used to correct the jade polishing sleeve (5).

5. The enhanced polishing device for high load-bearing motor cylinder bores according to claim 1, characterized in that, The taper of the cone is 1:

50.

6. The enhanced polishing device for high load-bearing motor cylinder bores according to claim 1, characterized in that, Also includes: Tightening loop (10); The tensioning sleeve (10) is provided with a hexagonal screw hole (11); The handle is provided with an external thread (3), and the tensioning sleeve (10) is threaded onto the external thread (3). By rotating, the jade polishing sleeve (5) or grinding sleeve (9) is pushed to move on the cone head. The position of the tension sleeve (10) on the tool holder is fixed by a screw set in the hexagonal screw hole (11).

7. The enhanced polishing device for high load-bearing motor cylinder bores according to claim 1, characterized in that, The handle is provided with a pin hole (4); The pin hole (4) is used to insert the handle to rotate the strengthening polishing device.

8. A method for strengthening polishing a high-load-bearing motor cylinder bore using a strengthening polishing apparatus as described in any one of claims 1-7, characterized in that, include: The grinding sleeve (9) is installed on the cone head, and the grinding liquid is applied to the grinding sleeve (9). By moving the high load motor cylinder and the grinding sleeve (9) relative to each other, the grinding liquid is applied to the high load motor cylinder hole before polishing and the abrasive is embedded in the grinding liquid. Remove the grinding sleeve (9) from the cone head and install the jade polishing sleeve (5) on the cone head to perform enhanced polishing on the high load-bearing motor cylinder hole to form a dense composite surface.

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