A new type of cylinder bore coaxiality inspection tool and inspection method

Abstract

The present invention relates to a novel cylinder bore coaxiality inspection tool and inspection method. The inspection tool comprises a piston slidably mounted within the cylinder bore, a rotating shaft axially extending through the piston and rotatably connected to the piston, and a lever fixed to the rotating shaft. The lever is located on the side of the piston facing the cylinder bore. A connecting rod is hinged to the lever via a transverse axis, and a micrometer is mounted on the connecting rod. During inspection, the tool is placed entirely within the sleeve, and adjustment to different inspection positions is achieved by moving the piston. This method eliminates the need to damage the finished cylinder, making operation convenient, achieving full inspection requirements, and improving inspection efficiency.

Description

Technical Field

[0001] The present invention relates to the field of machining inspection, and in particular to a novel cylinder inner hole coaxiality inspection tool and an inspection method. Background Art

[0002] In the field of machining, finished product size inspection is an indispensable link, especially for cylinder parts. Due to different processing requirements for the inner hole, re-clamping is required during boring and finish turning during the machining process. The coaxiality of the cylinder inner hole may exceed 0.04mm~0.05mm, so size inspection is particularly important.

[0003] At present, the conventional method for detecting the coaxiality of the cylinder bore is to achieve it through three-coordinate measurement. The use of three-coordinate measurement has too many limitations on the requirements for environmental conditions, measurement range and the size of the measured parts. As a result, the finished cylinder needs to be sawed open during measurement, and the cylinder cannot be used after being sawed open. The inspection cost is very high, the inspection time takes more than 1 hour, the inspection efficiency is low, and it cannot meet the requirements of full inspection. Only one or two pieces can be randomly inspected. Summary of the Invention

[0004] Aiming at the deficiencies of the prior art, the present invention provides a novel cylinder inner bore coaxiality inspection tool, which does not require destruction of the finished cylinder and is very convenient to operate.

[0005] The present invention is achieved through the following technical solution, which provides a new type of cylinder inner hole coaxiality inspection tool, including a piston slidably arranged in the cylinder inner hole, a rotating shaft passing through the piston axially and rotatably connected to the piston, and a shift rod fixed on the rotating shaft. The shift rod is located on the side of the piston facing the cylinder fine-turning hole. A connecting rod is hinged on the shift rod through a horizontal axis, and a micrometer is installed on the connecting rod.

[0006] This solution uses a piston as the moving body, while maintaining good coaxiality with the cylinder, providing a consistent axis for the rotation of the micrometer in the boring area and the fine turning area, thereby improving the accuracy of the 360-degree rotation inspection of the micrometer. The lever and the connecting rod are hinged through the horizontal axis, which facilitates the adjustment of the radial position of the micrometer and meets the requirements of rapid adjustment for inspections at different hole diameters.

[0007] As an optimization, the piston's outer surface is provided with a circumferentially closed arc groove, within which a wear-resistant support ring is positioned. The outer diameter of the wear-resistant support ring is larger than the piston's outer diameter and matches the cylinder's inner diameter, while the inner diameter of the wear-resistant support ring matches the diameter of the arc groove. This optimization solution creates a gap between the cylinder and piston, preventing scratches between the two. The arc groove, which matches the wear-resistant support ring, also facilitates its installation and positioning.

[0008] As an optimization, two arc grooves are distributed axially. The axial distance between the two arc grooves is greater than or equal to 1 / 2 of the piston's axial length. This optimization solution, by setting the number and spacing of the arc grooves and utilizing the principle of two points defining a straight line, further improves the coaxiality of the piston and cylinder, preventing piston tilt.

[0009] As an optimization, the rotating shaft includes a threaded section, a rotating section, and a limiting section, sequentially distributed along the axial direction. The piston is provided with a central through-hole that matches the rotating section. The limiting section has a larger diameter than the central through-hole, and the threaded section is provided with a fixing nut with an outer diameter larger than the central through-hole. This optimization solution, through the provision of threaded sections and limiting sections, limits the axial movement of the rotating shaft, preventing it from falling off the piston and facilitating its installation. The mutual adaptation of the rotating section and the central through-hole prevents radial runout of the rotating shaft, further improving inspection accuracy.

[0010] As an optimization, the limiting section includes a radially extending insertion hole, into which the lever is inserted. A set screw is threadedly connected to the limiting section, which pushes the lever axially along the rotation axis. This optimized lever fixing method facilitates adjustment of the lever's radial position, thereby facilitating adjustment of the position of the micrometer indicator. After loosening the set screw, the lever can be moved along the insertion hole to adjust the distance between the dial indicator and the hole wall.

[0011] The present solution also provides a method for inspecting the coaxiality of the inner bore of a cylinder using the above-mentioned inspection fixture, comprising the following steps: rotating the connecting rod so that the dial indicator is within the axial projection range of the piston to prevent the dial indicator from being damaged when the fixture is installed, and then pushing the fixture into the cylinder to be inspected, and the piston slides along the axial direction of the cylinder until the dial indicator is in the boring area; by adjusting the radial position of the shift rod and the angle of the connecting rod, the inspection end of the dial indicator is pressed against the inner wall of the boring hole, the limit section is pressed against the piston and the rotating shaft is rotated to move the dial indicator 360 degrees along the inner wall of the boring hole, and the upper and lower maximum deviation values ​​are recorded and obtained. A1. During the rotation of the rotating shaft, the limit section always fits with the piston; by rotating the connecting rod, the dial indicator is within the axial projection range of the piston, and the piston is pulled to slide along the axial direction of the cylinder until the dial indicator is in the fine turning area; by adjusting the radial position of the lever and the angle of the connecting rod, the detection end of the dial indicator is pressed against the inner wall of the fine turning hole, the limit section is pressed against the piston and the rotating shaft is rotated to move the dial indicator 360 degrees along the inner wall of the fine turning hole, and the upper and lower maximum deviation values ​​A2 are recorded and obtained. The difference between A1 and A2 is the coaxiality error. During the rotation of the rotating shaft, the limit section always fits with the piston.

[0012] The beneficial effects of the present invention are as follows: during inspection, the tooling is placed as a whole into the sleeve, and adjustment to different inspection positions can be achieved by moving the piston without destroying the finished cylinder. The operation is convenient, full inspection requirements can be achieved, and inspection efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a state diagram of the present invention when inspecting the boring area;

[0014] Figure 2 This is a state diagram of the present invention when inspecting the fine turning hole area;

[0015] As shown in the figure:

[0016] 1. Fixing nut, 2. Piston, 3. Wear-resistant support ring, 4. Push rod, 5. Set screw, 6. Rotating shaft, 7. Connecting rod, 8. Micrometer. DETAILED DESCRIPTION

[0017] In order to clearly illustrate the technical features of this solution, this solution is described below through specific implementation methods.

[0018] like Figure 1 The figure shows a new type of cylinder inner bore coaxiality inspection tool, which includes a piston 2 slidably arranged in the cylinder inner bore, a rotating shaft 6 axially passing through the piston 2 and rotatably connected to the piston 2, and a shift rod 4 radially fixed on the rotating shaft. The shift rod is located on the side of the piston facing the cylinder fine-turning hole. A connecting rod 7 is hinged on the shift rod through a horizontal axis, and a micrometer 8 is installed on the connecting rod 7.

[0019] To prevent wear between the piston and cylinder, this embodiment features two circumferentially closed arc grooves on the piston's outer surface. The arc grooves are spaced axially, with the axial distance between the two arc grooves being greater than or equal to half the piston's axial length. A wear-resistant support ring 3 is positioned within the arc groove. Its inner diameter matches the diameter of the arc groove, while its outer diameter is greater than the piston's outer diameter and matches the cylinder's inner diameter. This creates a gap between the cylinder's inner wall and the piston, preventing scratches on the finished cylinder from the piston.

[0020] The rotating shaft includes a threaded section, a rotating section and a limiting section distributed in sequence along the axial direction. A central through hole adapted to the rotating section is opened on the piston. The diameter of the limiting section is larger than the diameter of the central through hole. A fixing nut 1 with an outer diameter larger than the diameter of the central through hole is provided on the threaded section. The fixing nut 1 and the limiting section can prevent the rotating shaft from falling out of the piston.

[0021] The limiting section is provided with a radially penetrating jack, in which the shift rod 4 is inserted. The limiting section is threadedly connected with a set screw 5 which is axially pressed against the shift rod along the rotating shaft, and the shift rod and the rotating shaft are fixed relative to each other by the set screw.

[0022] The method for inspecting the coaxiality of the inner bore of a cylinder using the inspection tool of this embodiment includes the following steps:

[0023] 1. Turn the connecting rod to make the dial indicator within the axial projection range of the piston to avoid damage to the dial indicator when installing the tooling. Then push the tooling into the cylinder to be tested, and slide the piston along the axial direction of the cylinder until the dial indicator is in the boring area.

[0024] 2. Adjust the radial position of the lever and the angle of the connecting rod so that the detection end of the dial indicator touches the inner wall of the bore. Press the limit section against the piston and rotate the rotary shaft to move the dial indicator 360 degrees along the inner wall of the bore. Record and determine the maximum upper and lower deviation values ​​A1. During the rotation of the rotary shaft, the limit section always fits the piston.

[0025] 3. Turn the connecting rod to make the dial indicator within the axial projection range of the piston, and pull the piston to slide along the axial direction of the cylinder until the dial indicator is in the fine turning area;

[0026] 4. By adjusting the radial position of the lever and the angle of the connecting rod, the detection end of the dial indicator is pressed against the inner wall of the fine-turned hole. The limit section is pressed against the piston and the rotating shaft is rotated to move the dial indicator 360 degrees along the inner wall of the fine-turned hole. The upper and lower maximum deviation values ​​A2 are recorded and obtained. The difference between A1 and A2 is the coaxiality error. During the rotation of the rotating shaft, the limit section is always in contact with the piston.

[0027] This inspection tool does not need to destroy the finished cylinder when used, which reduces inspection costs, improves inspection efficiency, and can meet full inspection requirements. The measurement accuracy reaches 0.001mm, which fully meets the requirements for cylinder bore inspection with coaxiality requirements of 0.04~0.05mm. It is also simple to operate and fast to inspect. The average inspection time for each cylinder is 2 minutes, which meets the requirements in terms of inspection cost control and full inspection.

[0028] Of course, the above description is not limited to the above examples. Technical features not described in the present invention can be achieved by or by adopting existing technologies, which will not be described here. The above embodiments and drawings are only used to illustrate the technical solutions of the present invention and are not limitations of the present invention. The present invention is described in detail with reference to the preferred implementation methods. Ordinary technicians in this field should understand that changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention do not depart from the purpose of the present invention and should also fall within the scope of protection of the claims of the present invention.

Claims

1. A method for inspecting the coaxiality of a cylinder bore using a novel cylinder bore coaxiality inspection tool, characterized in that: The novel cylinder bore coaxiality inspection tool comprises a piston (2) slidably mounted in the cylinder bore, a rotary shaft (6) axially passing through the piston and rotatably connected to the piston, and a shift rod (4) fixed to the rotary shaft, the shift rod being located on the side of the piston facing the cylinder bore, a connecting rod (7) being hinged to the shift rod via a transverse axis, and a micrometer (8) being mounted on the connecting rod; The rotating shaft comprises a threaded section, a rotating section and a limiting section which are sequentially distributed along the axial direction; a central through hole adapted to the rotating section is provided on the piston; the diameter of the limiting section is larger than the diameter of the central through hole; and a fixing nut (1) having an outer diameter larger than the diameter of the central through hole is provided on the threaded section; The cylinder bore coaxiality inspection method comprises the following steps: (1) By rotating the connecting rod, make the dial indicator within the axial projection range of the piston to avoid the dial indicator being damaged when installing the tooling, then push the tooling into the cylinder to be tested, and slide the piston along the axial direction of the cylinder until the dial indicator is in the boring area; (2) By adjusting the radial position of the lever and the angle of the connecting rod, the detection end of the dial indicator is pressed against the inner wall of the bore, the limit section is pressed against the piston and the rotary shaft is rotated to move the dial indicator 360 degrees along the inner wall of the bore, and the upper and lower maximum deviation values ​​A1 are recorded and obtained. During the rotation of the rotary shaft, the limit section is always in contact with the piston; (3) Turn the connecting rod so that the dial indicator is within the axial projection range of the piston, and pull the piston to slide along the axial direction of the cylinder until the dial indicator is in the fine turning area; (4) By adjusting the radial position of the lever and the angle of the connecting rod, the detection end of the micrometer is pressed against the inner wall of the fine-turning hole. The limit section is pressed against the piston and the rotating shaft is rotated to move the micrometer 360 degrees along the inner wall of the fine-turning hole. The upper and lower maximum deviation values ​​A2 are recorded and obtained. The difference between A1 and A2 is the coaxiality error. During the rotation of the rotating shaft, the limit section is always in contact with the piston.

2. The cylinder bore coaxiality inspection method using the novel cylinder bore coaxiality inspection tool according to claim 1 is characterized in that: The outer circumferential surface of the piston is provided with an arc groove closed in the circumferential direction, and a wear-resistant support ring (3) is provided in the arc groove. The outer diameter of the wear-resistant support ring is larger than the outer diameter of the piston and is adapted to the inner diameter of the cylinder, and the inner diameter of the wear-resistant support ring is adapted to the diameter of the arc groove.

3. The cylinder bore coaxiality inspection method using the novel cylinder bore coaxiality inspection tool according to claim 2 is characterized in that: There are two arc grooves distributed along the axial direction, and the axial distance between the two arc grooves is greater than or equal to 1 / 2 of the axial length of the piston.

4. The cylinder bore coaxiality inspection method using the novel cylinder bore coaxiality inspection tool according to claim 1 is characterized in that: The limiting section is provided with a radially penetrating insertion hole, the shifting rod (4) is inserted into the insertion hole, and the limiting section is threadedly connected with a set screw (5) that is axially pushed to the shifting rod along the rotating shaft.

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