Special-shaped cylinder sleeve stepped arc surface positioning device and method

Abstract

The invention provides a stepped arc surface positioning device and method for a special-shaped cylinder sleeve, and belongs to the technical field of machining fixtures, the stepped arc surface positioning device comprises a base, a plurality of guide columns are vertically arranged on the base, a movable pressing plate capable of moving up and down along the guide columns is arranged above the base, and meanwhile, a driving rod for driving the movable pressing plate to move up and down is arranged on the base; a water ring is arranged in the center of the movable pressing plate, and an upper air bag assembly, a lower air bag assembly and a supporting sleeve are sequentially arranged below the water ring; the upper air bag assembly and the lower air bag assembly are connected with a machine tool hydraulic system through oil ways respectively. According to the complex design structure of the appearance of the cylinder sleeve and the precision requirement of each part, under the condition that interference of each structure of the stepped arc surface is considered, the positioning datum plane is accurately selected, and positioning and clamping in the machining process of the inner hole of the cylinder sleeve can be accurately achieved.

Description

Technical Field

[0001] This invention belongs to the field of machining fixture technology, and in particular relates to a stepped arc surface positioning device and method for irregular cylinder liners. Background Technology

[0002] As an important component of the diesel engine combustion chamber, the cylinder liner is a core component of the diesel engine. During operation, it is subjected to high temperature and high pressure environment for a long time. Its inner hole must have functions such as combustion chamber sealing, piston guidance and heat transfer. In addition, during the operation of the diesel engine, the inner surface of the cylinder liner must withstand repeated impacts from mechanical loads such as high thermal load and severe alternating side pressure caused by the high speed reciprocating motion of the piston. Therefore, the machining quality of its inner hole is extremely important.

[0003] A new type of diesel engine cylinder liner design differs from traditional diesel engine cylinder liners, such as... Figure 1 As shown, it integrates the design structure of the diesel engine cylinder head and cylinder liner. Based on the traditional thin-walled cylindrical cylinder liner structure, the function of the cylinder head is added. Therefore, the structure of the cylinder liner becomes a combination of multi-step cylindrical surface and asymmetric spatial structure, which makes the selection of positioning method and positioning surface more complicated.

[0004] Because the traditional diesel engine cylinder liner has a relatively simple shape and is generally a cylindrical structure with little variation, and has a relatively small length-to-diameter ratio, it has strong stability under vertical machining conditions such as honing. During machining, the large end is usually facing down, and a high-precision outer cylindrical surface is selected to make a positioning seat ring, and then a pressure block is used to press it on the upper end.

[0005] Currently, the factory lacks a suitable positioning and clamping device for this new type of cylinder liner. The positioning device of the traditional cylinder liner interferes with the cylinder liner's external structure, and the positioning and clamping range cannot cover the cylinder liner's dimensions. Furthermore, the factory currently uses vertical honing for all honing processes. Since the cylinder liner's length-to-diameter ratio is much larger than the factory's existing cylinder liners, the existing technology cannot achieve stable positioning and processing during honing. Summary of the Invention

[0006] This invention addresses the problem of the lack of suitable positioning and clamping devices for novel cylinder liners. It provides a stepped arc-shaped positioning device and method for irregularly shaped cylinder liners, capable of precise positioning and clamping during the vertical honing process of novel cylinder liners.

[0007] The technical solution adopted by the present invention, a stepped arc surface positioning device and method for irregular cylinder liners, is as follows:

[0008] A stepped arc-shaped positioning device for irregular cylinder liners includes a base, on which multiple guide pillars are vertically arranged, and above the base is a movable pressure plate that can move up and down along the guide pillars. At the same time, a drive rod is provided on the base to drive the movable pressure plate to move up and down.

[0009] The center of the movable pressing plate is provided with a water ring, and the water ring is sequentially provided with an upper air bag assembly, a lower air bag assembly and a supporting sleeve below.

[0010] The further improvement of the above technical solution of the present application is that the upper air bag assembly comprises a first upper pressing cover, a first air bag body and a first lower pressing cover coaxially stacked from top to bottom, and the three form a sealed cavity through circumferentially distributed screws.

[0011] The further improvement of the above technical solution of the present application is that the lower air bag assembly comprises a second upper pressing cover, a second air bag body and a lower positioning ring coaxially stacked from top to bottom, and the three form a sealed cavity through circumferentially distributed screws.

[0012] The further improvement of the above technical solution of the present application is that a supporting ring is coaxially arranged in the first air bag body and the second air bag body.

[0013] The further improvement of the above technical solution of the present application is that the inner curved surface of the lower positioning ring is a stepped circular arc surface, and the minimum diameter section curvature radius R1 and the minimum outer diameter D1 of the cylinder sleeve satisfy: |R1-D1 / 2|≤0.05mm.

[0014] The further improvement of the above technical solution of the present application is that the first air bag body and the second air bag body each comprise an oil-resistant rubber layer, an aramid fiber reinforced layer and a stainless steel wire mesh layer arranged in sequence from inside to outside; and the radial deformation amount δ of the first air bag body and the second air bag body satisfies: δ≥0.15, wherein D is the nominal diameter.

[0015] The further improvement of the above technical solution of the present application is that the top of the supporting sleeve is provided with an annular flange, the inner diameter of the supporting sleeve is matched with the maximum inner diameter of the lower positioning ring, and the bottom end of the lower positioning ring is inserted into the top of the supporting sleeve to form cylinder sleeve axial positioning.

[0016] A stepped circular arc surface positioning method for a special-shaped cylinder sleeve, using the device described above, comprises the following steps,

[0017] S1, placing the cylinder sleeve in the lower positioning ring so that the lower end surface of the cylinder sleeve contacts the annular flange of the supporting sleeve;

[0018] S2, starting the driving rod to drive the movable pressing plate to move downward until the first lower pressing cover of the upper air bag assembly contacts the upper end surface of the cylinder sleeve;

[0019] S3, injecting hydraulic oil into the oil line to make the first air bag body and the second air bag body expand radially synchronously and press the outer cylindrical surface of the upper segment diameter D2 and the lower segment diameter D1 of the cylinder sleeve respectively;

[0020] S4, when the pressure sensor detects that the air bag pressure reaches the set value, stop oil injection and lock the pressure valve;

[0021] S5, after the processing is completed, the pressure is released and reset.

[0022] Thanks to the above technical solutions, the technical progress achieved by the present application is:

[0023] According to the design structure of the complex outer shape of the cylinder sleeve and the precision requirements of each part, and under the condition of considering the interference of each structure of the stepped arc surface, the positioning reference surface is accurately selected, so that the positioning and clamping in the cylinder sleeve hole machining process can be accurately realized. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a front view structural schematic diagram of a special-shaped cylinder sleeve stepped arc surface positioning device provided by the present application;

[0025] Figure 2 is a top view structural schematic diagram of a special-shaped cylinder sleeve stepped arc surface positioning device provided by the present application.

[0026] In the drawings: 1, base; 2, guide column; 3, movable pressing plate; 4, driving rod; 5, water ring;

[0027] 6, upper air bag assembly; 61, first upper pressing cover; 62, first air bag body; 63, first lower pressing cover;

[0028] 7, lower air bag assembly; 71, second upper pressing cover; 72, second air bag body; 73, lower positioning ring;

[0029] 8, support sleeve; 9, support ring. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the present application more clear and explicit, the present application will be further described in detail below with reference to specific embodiments and drawings. In the following description, the description of known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present application.

[0031] First refer to Figure 1 and Figure 2 It can be seen that the present application provides a special-shaped cylinder sleeve stepped arc surface positioning device, which comprises a base 1, a plurality of guide columns 2 are vertically arranged on the base 1, a movable pressing plate 3 capable of moving up and down along the guide columns 2 is arranged above the base 1, and a driving rod 4 for driving the movable pressing plate 3 to move up and down is arranged on the base 1; the driving rod 4 can be selected from the commonly used hydraulic rod, electric push rod and pneumatic rod in the prior art, etc.

[0032] The center of the movable pressing plate 3 is provided with a water ring 5, and the water ring 5 is sequentially provided with an upper air bag assembly 6, a lower air bag assembly 7 and a supporting sleeve 8 from bottom to top.

[0033] The upper air bag assembly 6 in the application comprises a first upper pressing cover 61, a first air bag body 62 and a first lower pressing cover 63 which are coaxially stacked from top to bottom, and the three form a sealed cavity through uniformly distributed screws.

[0034] The first air bag body 62 and the second air bag body 72 are coaxially provided with a supporting ring 9, and the first air bag body 62 and the second air bag body 72 each comprise an oil-resistant rubber layer, an aramid fiber reinforced layer and a stainless steel wire mesh layer which are sequentially arranged from inside to outside.

[0035] The inner curved surface of the lower positioning ring 73 is a stepped circular arc surface, and the minimum diameter section curvature radius R1 of the inner curved surface and the minimum outer diameter D1 of the cylinder sleeve satisfy the condition: |R1-D1 / 2|≤0.05mm.

[0036] The device in the embodiment is divided into two parts by the adjusting block, and the upper part mainly comprises four guide columns 2, two hydraulic rods, a movable pressing plate 3, a water ring 5, air bag upper and lower pressing covers, an upper air bag and an air bag body, a supporting ring 9 and the like.

[0037] The lower part mainly comprises a second upper pressing cover 71, a lower air bag main part (the structure is basically the same as that of the upper air bag), a lower positioning ring 73 and a supporting sleeve 8 and the like.

[0038] The application also provides a stepped circular arc surface positioning method for a special-shaped cylinder sleeve, comprising the following steps:

[0039] S1, placing the cylinder sleeve in the lower positioning ring 73 so that the lower end surface of the cylinder sleeve contacts the annular flange of the support sleeve 8;

[0040] S2, starting the drive rod 4 to drive the movable pressing plate 3 to move downward until the first lower pressing cover 63 of the upper air bag assembly 6 contacts the upper end surface of the cylinder sleeve;

[0041] S3, injecting hydraulic oil into the oil circuit to make the first air bag body 62 and the second air bag body 72 expand radially synchronously to press the outer circular surface of the upper section diameter D2 and the lower section diameter D1 of the cylinder sleeve, respectively;

[0042] S4, when the pressure sensor detects that the air bag pressure reaches the set value, stop injecting oil and lock the pressure valve;

[0043] S5, after the processing is completed, the pressure is released and reset.

[0044] The working principle of the stepped circular arc surface positioning device and method for the special-shaped cylinder sleeve in the embodiment is as follows: the cylinder sleeve is placed in the lower part of the positioning device, the lower end surface is tightly attached to the end surface of the lower positioning ring 73, the drive rod 4 is lowered under the control of the machine tool hydraulic system, the movable pressing plate 3, the water ring 5, the upper air bag assembly 6 and other structures are driven to fall along the guide column 2 direction until the first upper pressing cover 61 of the upper air bag assembly 6 presses the upper end surface of the cylinder sleeve, the air bag part control hydraulic valve is manually opened, the hydraulic oil enters the first air bag body 62 and the second air bag body 72 through the oil injection hole, the air bag is inflated to press the positioning surfaces with different diameters of the cylinder sleeve, and the centering effect is realized at the same time.

[0045] In the above embodiment, the application provides a stepped circular arc surface positioning device and method for a special-shaped cylinder sleeve. According to the design structure of the complex cylinder sleeve shape and the precision requirements of each part, the positioning reference surface is accurately selected under the consideration of the interference of each structure of the stepped circular arc surface, and the positioning and clamping during the cylinder sleeve hole machining process can be accurately realized.

[0046] The above-described embodiments only describe the preferred embodiments of the application and do not limit the concept and scope of the application. Various modifications and improvements to the technical solutions of the application made by those skilled in the art without departing from the design concept of the application shall fall within the protection scope of the application. The technical content claimed by the application has been fully recorded in the claims.

Claims

1. A stepped circular arc surface positioning device for a profiled cylinder liner, characterized by: The base (1) is vertically provided with a plurality of guide columns (2), and an active pressing plate (3) is arranged above the base (1) and can move up and down along the guide columns (2); meanwhile, the base (1) is provided with a driving rod (4) for driving the active pressing plate (3) to move up and down; The center of the active pressing plate (3) is provided with a water ring (5), and the water ring (5) is sequentially provided with an upper air bag assembly (6), a lower air bag assembly (7) and a support sleeve (8) from bottom to top; wherein the upper air bag assembly (6) and the lower air bag assembly (7) are connected with a machine tool hydraulic system through an oil circuit respectively.

2. The stepped circular-arc positioning device of the special-shaped cylinder liner according to claim 1, characterized in that: The upper air bag assembly (6) comprises a first upper pressing cover (61), a first air bag body (62) and a first lower pressing cover (63) coaxially stacked from top to bottom, and the three form a sealed cavity through circumferentially distributed screws.

3. The stepped circular-arc positioning device of claim 2, wherein: The lower air bag assembly (7) comprises a second upper pressing cover (71), a second air bag body (72) and a lower positioning ring (73) coaxially stacked from top to bottom, and the three form a sealed cavity through circumferentially distributed screws.

4. The stepped circular-arc positioning device of claim 3, wherein: The first air bag body (62) and the second air bag body (72) are coaxially provided with a support ring (9) respectively.

5. The stepped circular-arc positioning device of claim 3, wherein: The inner curved surface of the lower positioning ring (73) is a stepped circular arc surface, and the minimum diameter section curvature radius R1 and the minimum outer diameter D1 of the cylinder sleeve satisfy: |R1-D1 / 2|≤0.05mm.

6. The stepped circular-arc positioning device of claim 3, wherein: The first air bag body (62) and the second air bag body (72) each comprise an oil-resistant rubber layer, an aramid fiber reinforced layer and a stainless steel wire mesh layer arranged in sequence from inside to outside; and the radial deformation amount δ of the first air bag body (62) and the second air bag body (72) satisfies: δ≥0.15, wherein D is the nominal diameter.

7. The stepped circular-arc positioning device of claim 3, wherein: The support sleeve (8) is provided with an annular flange at the top, the inner diameter of the support sleeve (8) is matched with the maximum inner diameter of the lower positioning ring (73), and the bottom end of the lower positioning ring (73) is inserted into the top of the support sleeve (8) to form axial positioning of the cylinder sleeve.

8. A stepped circular arc surface positioning method for a special-shaped cylinder liner, characterized in that: The device of any one of claims 1-7 is used, comprising the following steps, S1, placing the cylinder sleeve in the lower positioning ring (73) so that the lower end surface of the cylinder sleeve contacts the annular flange of the support sleeve (8); S2, starting the driving rod (4) to drive the active pressing plate (3) to move downward until the first lower pressing cover (63) of the upper air bag assembly (6) contacts the upper end surface of the cylinder sleeve; S3, injecting hydraulic oil into the oil circuit to make the first air bag body (62) and the second air bag body (72) expand radially synchronously and press the outer circular surface of the upper segment diameter D2 and the lower segment diameter D1 of the cylinder sleeve respectively; S4, when the pressure sensor detects that the air bag pressure reaches the set value, stop injecting oil and lock the pressure valve; S5, after the machining is completed, the pressure is released and reset.

Images