Laser marking tool and method for marine diesel engine base

Abstract

A laser marking tool and method for a marine diesel engine base is disclosed. The base is inverted on a marking platform and internally houses a plurality of coaxial main bearing seats with semi-axial holes. The tool comprises a laser interferometer, a light receptor assembly, and a measuring strut. The measuring strut extends outward and is horizontally supported on the inner walls of the semi-axial holes of the main bearing seat. The light receptor assembly is fixedly connected to the measuring strut and comprises a light receptor and a light receptor mounting bracket. The light receptor is connected to the middle of the measuring strut via the light receptor mounting bracket. The laser interferometer is placed on the marking platform below the main bearing seat and projects a laser line vertically toward the light receptor assembly above. The laser line serves as a marking reference for the horizontal centerline of the semi-axial holes, the vertical centerline of the semi-axial holes, the center of the semi-axial holes, the X-axis reference line of the base, the machining surface allowance line, and the boring allowance line. The present invention simplifies the marking process steps and operations, improves marking efficiency, increases marking accuracy, reduces processing time, and improves the efficiency of the base processing.

Description

Technical Field

[0001] The invention relates to a manufacturing process of a marine diesel engine, in particular to a laser marking tool and method for a marine diesel engine base, belonging to the technical field of mechanical processing. Background Art

[0002] The engine base of a marine low-speed diesel engine is the base of the entire diesel engine. Figure 1 and Figure 2 The upper part of the machine base 1 is the upper plane 1-1 of the machine base, and the lower part is the lower plane 1-2 of the machine base. The most important processing part is the multiple coaxial main bearing seats 1-3 located inside, which are used to install the crankshaft. In order to ensure that each processing plane has an allowance when the machine base 1 is processed, the machine base 1 will be marked before processing to ensure the allowance, and at the same time, it will be checked whether the end face deviation of the main bearing seat 1-3 welding is less than plus or minus 3mm (welding deviation outside the range will affect the crankshaft's gear shifting). Since the marking reference center of the machine base 1 is at the center of the half-shaft hole 1-4 of the main bearing seat 1-3, which is a virtual point, the currently commonly used marking method is to mark out the processing allowance of each surface in an indirect way.

[0003] The traditional marking method has the following main problems:

[0004] 1) Since the marking reference uses an indirect line and the machining allowances of the remaining surfaces are marked out separately, many auxiliary lines need to be drawn during the operation, and many marking values ​​need to be converted, which easily leads to calculation errors and cumulative errors, thus affecting the marking accuracy.

[0005] 2) Drawing auxiliary lines is time-consuming and labor-intensive, which affects the efficiency of the marking operation.

[0006] 3) If the internal main bearing seat 1-3 welding deviation is large, subsequent machine tool processing is required, which consumes machine tool time. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to overcome the defects of existing marking methods and tools, and provide a laser marking tool and method for marine diesel engine base, so as to achieve the effects of reducing processing steps, simplifying operation steps, improving marking efficiency and stabilizing processing quality.

[0008] The present invention adopts the following technical solutions to solve the technical problems:

[0009] A laser marking tool for a marine diesel engine base, wherein the base is inverted on a marking platform, comprises an upper plane of the base and a bottom plane of the base, and is internally provided with a plurality of coaxial main bearing seats with semi-axial holes, characterized in that: the laser marking tool comprises a laser interferometer, a light receiver assembly and a measuring strut; the two ends of the measuring strut are spread outward and horizontally supported on the inner walls on both sides of the semi-axial holes of the main bearing seat; the light receiver assembly is fixedly connected to the measuring strut, comprises a light receiver and a light receiver mounting bracket, and the light receiver is connected and fixed to the middle part of the measuring strut through the light receiver mounting bracket; the laser interferometer is placed on the marking platform below the main bearing seat, and vertically projects a laser line toward the light receiver assembly above, which serves as a marking reference for the horizontal center line of the semi-axial hole, the vertical center line of the semi-axial hole, the center of the semi-axial hole, the X-axis reference line of the base, the machining surface allowance line and the boring allowance line.

[0010] Furthermore, the laser interferometer is provided with a 360-degree rotating base, which can automatically adjust the level and has a built-in horizontal and vertical laser navigation function.

[0011] Furthermore, the measuring strut includes a strut having a flat steel sheet in the middle for marking the actual reference, and spherical support heads connected at both ends by adjusting bolts for supporting and fixing the measuring strut on the inner wall of the semi-axial hole.

[0012] Furthermore, the photoreceiver mounting bracket includes a fixing bracket and a fastening bolt, the fastening bolt is threadedly connected to the upper part of the fixing bracket, and the lower end is tightly pressed against the measuring support rod to fix the photoreceiver mounting bracket on the measuring support rod. The side of the fixing bracket is a side edge of the mounting bracket perpendicular to the measuring support rod.

[0013] Furthermore, the photoreceiver includes a spirit level, a front face of the photoreceiver and a back face of the photoreceiver. The spirit level is arranged on the front face of the photoreceiver for adjusting the level of the photoreceiver. The front face of the photoreceiver is also provided with a light receiving area for passing the laser. The back face of the photoreceiver is fixed to the lower part of the fixing frame by bolts. A vertical photoreceiver reference line is provided on the back face of the photoreceiver. When installed, the side edge of the mounting frame coincides with the photoreceiver reference line.

[0014] Furthermore, a plane formed by the light receiver reference line and the light receiving area is perpendicular to the back surface of the light receiver.

[0015] Another technical solution of the present invention is:

[0016] A laser marking method for a marine diesel engine base implemented using the above-mentioned laser marking tool comprises the following specific steps:

[0017] 1) With the upper surface of the machine base facing downward, place the machine base upside down on the adjustable pad on the scribing platform, and use the scribing needle disk to adjust the adjustable pad according to the position of the upper surface of the machine base so that the machine base is in a horizontal position;

[0018] 2) Installing a set of measuring struts and light receiver assemblies in the semi-axial holes of the first gear main bearing seat at the free end of the machine base and in the semi-axial holes of the first gear main bearing seat at the output end, respectively, so that the light receiving areas of the front of the two light receivers are oriented in opposite directions, and then using a stylus to mark the horizontal center line of the semi-axial holes on the steel sheet of the measuring struts;

[0019] 3) Using a double clamp, a center point is determined between the inner walls of both sides of the semi-axial hole, and the light receiver assembly is fine-tuned based on the center point so that the light receiver reference line coincides with the center point;

[0020] 4) Place the laser interferometer on the marking platform below the first gear main bearing seat at the output end of the machine base, start the laser interferometer and project a laser line vertically upward, so that the laser line passes through the light receiver reference line of the light receiver assembly on the first gear main bearing seat at the output end and the light receiving area of ​​the light receiver assembly on the first gear main bearing seat at the free end respectively, and then mark the vertical center line of the semi-axial hole on the steel sheet of the measuring support rod at the output end according to the laser line. The intersection of the vertical center line and the horizontal center line on the steel sheet is the center of the semi-axial hole of the first gear main bearing seat at the output end, and use a single card to mark the boring allowance line of the semi-axial hole of the first gear main bearing seat at the output end according to the center of the semi-axial hole, and at the same time mark the remaining machining surface allowance lines of the output end of the machine base;

[0021] 5) Place the laser interferometer on the marking platform below the first gear main bearing seat at the free end of the machine base, start the laser interferometer and project a laser line vertically upward, so that the laser line passes through the light receiver reference line of the light receiver assembly on the first gear main bearing seat at the free end and the light receiving area of ​​the light receiver assembly on the first gear main bearing seat at the output end respectively, and then mark the vertical center line of the semi-axial hole on the steel sheet of the measuring support rod at the free end according to the laser line. The intersection of the vertical center line and the horizontal center line on the steel sheet is the center of the semi-axial hole of the first gear main bearing seat at the free end, and use a single card to mark the boring allowance line of the semi-axial hole of the first gear main bearing seat at the free end according to the center of the semi-axial hole, and at the same time mark the allowance lines of the remaining machining surfaces of the free end of the machine base;

[0022] 6) According to the laser line projected on the bottom of the main bearing seat, a scale is installed through a magnet so that one side of the scale is aligned with the laser line, thereby determining the X-axis reference line of the machine base on all main bearing seats.

[0023] Furthermore, the laser scribing method further comprises the steps of:

[0024] 7) Place the laser interferometer in the main bearing seat to be measured, start the laser interferometer to project a laser line, and make the laser line pass through the light receiving area of ​​the light receiver assembly on the first-gear main bearing seat at the output end and the light receiving area of ​​the light receiver assembly on the first-gear main bearing seat at the free end. Adjust the longitudinal direction to the size of the main bearing seat to be measured according to the scale to determine whether the end face position deviation of the main bearing seat is within ±3mm.

[0025] Furthermore, in the step 2), the support point of the support head of the measuring strut on the inner wall of the semi-axial hole of the main bearing seat is as close as possible to the opening edge of the semi-axial hole, and after installation, the light receiver is adjusted to a horizontal position by the level meter.

[0026] The differences and beneficial effects of the present invention over the prior art are as follows:

[0027] 1. The marking datum can be directly displayed on the steel sheet of the measuring strut, which makes the position more intuitive and the marking more accurate. It overcomes the defect of the traditional marking method that the center of the marking datum is a virtual point in the air, reduces the cumulative error caused by the use of auxiliary lines for measurement, and greatly improves the marking accuracy.

[0028] 2. Reduced a large number of unnecessary auxiliary lines and improved marking efficiency.

[0029] 3. Use laser to determine whether the end face position of each main bearing seat is out of tolerance. Subsequently, only the end faces that are out of tolerance need to be processed, without the need to process every end face, which reduces the machine tool's occupancy time.

[0030] The beneficial technical effects of the present invention include: simplifying the process steps and operations for machine base marking; utilizing a laser interferometer and measuring struts; reducing unnecessary auxiliary lines; improving marking efficiency and accuracy; and reducing subsequent processing time, thereby significantly increasing machine base processing efficiency. The present invention is widely applicable to large base parts that use coaxial circular or semicircular shaft holes as marking references. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a structural diagram of the machine base.

[0032] Figure 2 This is the front view of the base.

[0033] Figure 3 This is a schematic diagram of the measurement support rod and light receptor assembly.

[0034] Figure 4 It is a structural diagram of the measuring strut.

[0035] Figure 5 It is a structural diagram of the light receiver assembly.

[0036] Figure 6 This is a schematic diagram of the rear side of the light receiver assembly.

[0037] Figure 7 It is a structural diagram of a laser interferometer.

[0038] Figure 8 This is a schematic diagram of the installation of the light receiver assembly and the measurement support rod.

[0039] Figure 9 It is a schematic diagram of the free end and output end of the machine base.

[0040] Figure 10 This is a schematic diagram of the main bearing seat allowance inspection.

[0041] In the figure,

[0042] 1—Machine base, 1-1—Upper plane of machine base, 1-2—Bottom plane of machine base, 1-3—Main bearing seat, 1-4—Half-axle hole, 2—Measuring support rod, 2-1—Steel sheet, 2-2—Adjusting bolt, 2-3—Strut, 2-4—Support head, 3—Photoreceiver, 3-1—Front of photoreceiver, 3-2—Back of photoreceiver, 3-3—Level, 3-4—Light receiving area, 3-5—Photoreceiver reference line, 4—Photoreceiver mounting bracket, 4-1—Side edge of mounting bracket, 4-2—Fixed bracket, 4-3—Fasten bolt, 5—Photoreceiver assembly, 6—Laser interferometer, 7—Scale, A—Output end, F—Free end, O—Center of half-axle hole, Y—Horizontal center line, Z—Vertical center line. DETAILED DESCRIPTION

[0043] The present invention will be described in further detail below with reference to the accompanying drawings, but the scope of protection claimed in the present invention shall not be limited thereby.

[0044] The present invention is used for marking the engine base of marine diesel engines. It uses laser technology to convert the marking reference center from a virtual point in the air into an operational physical point. Figure 1 、 Figure 2 and Figure 8 The machine base 1 includes a machine base upper plane 1-1 and a machine base bottom plane 1-2, and is internally provided with a plurality of coaxial main bearing seats 1-3 with semi-axial holes 1-4.

[0045] Please refer to Figure 3 and Figure 7 The laser marking tool shown in the figure includes a laser interferometer 6, a light receiver assembly 5 and a measuring support rod 2, which are used together with common marking tools such as a marking platform, an adjustable pad, a marking needle disk, a single card, a double card, and a ruler.

[0046] See also Figure 7The laser interferometer 6 is a conventional laser interferometer that can project a visible laser line, has a built-in horizontal and vertical laser navigation function, and is equipped with a 360-degree rotating base that can automatically adjust the level.

[0047] Please refer to Figure 3 and Figure 4 The measuring rod 2 can be selected to a suitable length according to the diameter of the part hole; both ends are provided with adjusting bolts 2-2 and spherical crown-shaped support heads 2-4 for fixing the rod 2-3; a flat steel sheet 2-1 is provided in the middle of the rod 2-3 for marking the actual reference line. Figure 8 The two ends of the measuring strut 2 are stretched outward by rotating the adjusting bolt 2-2 and are horizontally supported on the inner walls on both sides of the half-shaft hole 1-4 of the main bearing seat 1-3.

[0048] Please refer to Figure 5 and Figure 6 The light receiver assembly 5 is fixedly connected to the measuring strut 2 and is composed of a light receiver 3 and a light receiver mounting bracket 4. The light receiver 3 is connected and fixed to the middle part of the measuring strut 2 through the light receiver mounting bracket 4.

[0049] The photoreceiver 3 includes a front side 3-1 and a back side 3-2 of the photoreceiver; the front side 3-1 of the photoreceiver is provided with a spirit level 3-3 for adjusting the level, and the front side 3-1 of the photoreceiver also has a light receiving area 3-4, and an indicator light will change when the laser passes through; the back side 3-2 of the photoreceiver is provided with a photoreceiver reference line 3-5, and the plane formed by the light receiving area 3-4 on the front side is perpendicular to the back side 3-2 of the photoreceiver.

[0050] See also Figure 6 The photoreceiver mounting frame 4 includes a fixing frame 4-2 and a fastening bolt 4-3; the fastening bolt 4-3 is connected to the upper part of the fixing frame 4-2 by a thread, and the lower end is tightly pressed against the measuring support rod 2, thereby fixing the photoreceiver mounting frame 4 on the measuring support rod 2; during installation, it is necessary to ensure that the side edge 4-1 of the mounting frame (the side of the fixing frame 4-2) coincides with the photoreceiver reference line 3-5.

[0051] The main contents of the method for marking a diesel engine base using the laser marking tool are as follows:

[0052] 1: With the upper plane 1-1 of the machine base facing downward, place the machine base 1 on the adjustable pad of the marking platform; adjust the adjustable pad, and use the stylus disc to adjust the stylus disc to the horizontal center line of the machine base 1 according to the plate thickness of the upper and lower planes.

[0053] 2. Please refer to Figure 9, install the measuring support rod 2 and the light receiver assembly 5 in the semi-axial hole 1-4 of the first gear main bearing seat 1-3 from the free end F and the semi-axial hole 1-4 of the first gear main bearing seat 1-3 from the output end A respectively; pay attention to the following when installing: 1. Control the distance between the two sides of the tightening point and the edge of the blank; 2. The light receiving areas 3-4 of the two light receiver assemblies 5 are installed facing each other; 3. The spirit level 3-3 of the light receiver 3 needs to be adjusted to be level; 4. Use a stylus disk to draw a horizontal center line Y on the steel sheet 2-1 of the measuring support rod 2.

[0054] Three: Use a double card to separate the center of the shaft hole according to the blank of the hole wall of the semi-axial hole 1-4, and fine-tune the light receiver component 5 according to the center of the shaft hole to ensure that the center point of the shaft hole is on the light receiver reference line 3-5 (or on the side edge 4-1 of the mounting frame).

[0055] Four: Please refer to Figure 9 , place a laser interferometer 6 on the ground of the marking platform of the output end A of the machine base 1, so that the vertical laser passes through the light receiver reference line 3-5 of the first-stage semi-axial hole 1-4 from the output end A, and the light receiving area 3-4 of the light receiver front 3-1 of the first-stage semi-axial hole 1-4 from the free end F; according to the laser line, draw the vertical center line Z on the steel sheet 2-1 of the measuring support rod 2, and at the same time draw the remaining machining surface allowances of the output end A of the machine base 1; at this time, the intersection on the steel sheet 2-1 of the measuring support rod 2 is the center O of the semi-axial hole of the main bearing seat 1-3 of the machine base 1, and use a single card to draw the boring allowance line of the semi-axial hole 1-4 according to the center O of the semi-axial hole.

[0056] 5. Place a laser interferometer 6 on the ground of the marking platform at the free end F of the machine base 1, so that the vertical laser passes through the light receiver reference line 3-5 of the first-stage semi-axial hole 1-4 from the free end F, and the light receiving area 3-4 of the light receiver front face 3-1 of the first-stage semi-axial hole 1-4 from the output end A; draw the vertical center line Z on the steel sheet 2-1 of the measuring support rod 2 according to the laser line, and draw the remaining machining surface allowances of the machine base free end F at the same time; use a single card to draw the boring allowance line according to the intersection point (semi-axial hole center O) on the steel sheet 2-1 of the measuring support rod 2.

[0057] Six: According to the projection line of the laser on the bottom of the main bearing seat 1-3, use a magnet to install the scale 7 so that one side of the scale 7 is collinear with the laser line, and determine the X-axis reference line according to the steps of the main bearing seat 1-3.

[0058] VII: Please refer to Figure 10 , place the laser interferometer 6 inside the main bearing seat 1-3 to be measured in the machine base 1, and make the laser pass horizontally through the light receiving area 3-4 on the front side of the light receiver 3-1 of the first gear semi-axle hole 1-4 from the output end A and the light receiving area 3-4 on the front side of the light receiver 3-1 of the first gear semi-axle hole 1-4 from the free end F, and adjust the longitudinal direction to the bearing seat size to be measured according to the scale 7 at the bottom of the main bearing seat 1-3 to determine whether its end face meets the range of plus or minus 3mm.

[0059] The above are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. The scope of protection claimed by the present invention should also include obvious changes and alternatives to the present invention.

Claims

1. A laser marking tool for a marine diesel engine base, wherein the base is inverted on a marking platform and comprises an upper plane and a bottom plane of the base, and is provided with a plurality of coaxial main bearing seats with half-shaft holes therein, characterized in that: The laser marking tooling includes a laser interferometer, a light receptor assembly and a measuring strut; the two ends of the measuring strut are spread outward and horizontally supported on the inner walls on both sides of the semi-axial hole of the main bearing seat; the light receptor assembly is fixedly connected to the measuring strut, including a light receptor and a light receptor mounting bracket, and the light receptor is connected and fixed to the middle part of the measuring strut via the light receptor mounting bracket; the laser interferometer is placed on the marking platform below the main bearing seat, and vertically projects a laser line toward the light receptor assembly above, which serves as a marking reference for the horizontal center line of the semi-axial hole, the vertical center line of the semi-axial hole, the center of the semi-axial hole, the X-axis reference line of the machine base, the machining surface allowance line and the boring allowance line; The measuring strut comprises a strut with a flat steel sheet in the middle for marking the actual reference, and spherical cap-shaped support heads connected at both ends by adjusting bolts for supporting and fixing the measuring strut on the inner wall of the semi-axial hole; The light receiver includes a level, a front side of the light receiver and a back side of the light receiver. The level is provided on the front side of the light receiver for adjusting the level of the light receiver. The front side of the light receiver is also provided with a light receiving area for passing the laser. The back side of the light receiver is fixed to the lower part of the fixing frame by bolts. A vertical light receiver reference line is provided on the back side of the light receiver. When installed, the side edge of the light receiver mounting frame coincides with the light receiver reference line. The plane formed by the light receiver reference line and the light receiving area is perpendicular to the back surface of the light receiver.

2. The laser marking tool for a marine diesel engine base according to claim 1, characterized in that: The laser interferometer is provided with a 360-degree rotating base, can automatically adjust the level, and has a built-in horizontal and vertical laser navigation function.

3. The laser marking tool for a marine diesel engine base according to claim 1, characterized in that: The photoreceiver mounting frame includes a fixing frame and a fastening bolt. The fastening bolt is connected to the upper part of the fixing frame through a thread, and the lower end is tightly pressed against the measuring support rod to fix the photoreceiver mounting frame on the measuring support rod. The side of the fixing frame is a side edge of the mounting frame perpendicular to the measuring support rod.

4. A laser marking method for a marine diesel engine base implemented using the laser marking tool of claim 1, characterized in that: The laser scribing method includes the following specific steps: 1) With the upper surface of the machine base facing downward, place the machine base upside down on the adjustable pad on the scribing platform, and use the scribing needle disk to adjust the adjustable pad according to the position of the upper surface of the machine base so that the machine base is in a horizontal position; 2) Install a set of measuring struts and light receiver assemblies in the semi-axial holes of the first gear main bearing seat at the free end of the machine base and in the semi-axial holes of the first gear main bearing seat at the output end, respectively, so that the light receiving areas on the front of the two light receivers face each other, and then use a stylus to mark the horizontal center line of the semi-axial holes on the steel sheet of the measuring struts; 3) Using a double clamp, a center point is determined between the inner walls of both sides of the semi-axial hole, and the light receiver assembly is fine-tuned based on the center point so that the light receiver reference line coincides with the center point; 4) Place the laser interferometer on the marking platform below the first gear main bearing seat at the output end of the machine base, start the laser interferometer and project a laser line vertically upward, so that the laser line passes through the light receiver reference line of the light receiver assembly on the first gear main bearing seat at the output end and the light receiving area of ​​the light receiver assembly on the first gear main bearing seat at the free end respectively, and then mark the vertical center line of the semi-axial hole on the steel sheet of the measuring support rod at the output end according to the laser line. The intersection of the vertical center line and the horizontal center line on the steel sheet is the center of the semi-axial hole of the first gear main bearing seat at the output end, and use a single card to mark the boring allowance line of the semi-axial hole of the first gear main bearing seat at the output end according to the center of the semi-axial hole, and at the same time mark the allowance lines of the remaining machining surfaces of the output end of the machine base; 5) Place the laser interferometer on the marking platform below the first gear main bearing seat at the free end of the machine base, start the laser interferometer and project a laser line vertically upward, so that the laser line passes through the light receiver reference line of the light receiver assembly on the first gear main bearing seat at the free end and the light receiving area of ​​the light receiver assembly on the first gear main bearing seat at the output end respectively, and then mark the vertical center line of the semi-axial hole on the steel sheet of the measuring support rod at the free end according to the laser line. The intersection of the vertical center line and the horizontal center line on the steel sheet is the center of the semi-axial hole of the first gear main bearing seat at the free end. Use a single card to mark the boring allowance line of the semi-axial hole of the first gear main bearing seat at the free end according to the center of the semi-axial hole, and at the same time mark the allowance lines of the remaining machining surfaces of the free end of the machine base; 6) Based on the laser line projected on the bottom of the main bearing seat, a scale is installed through a magnet so that one side of the scale is aligned with the laser line, thereby determining the X-axis reference line of the machine base on all main bearing seats.

5. The laser marking method for a marine diesel engine base according to claim 4, characterized in that: The laser scribing method further comprises the steps of: 7) Place the laser interferometer in the main bearing seat to be measured, start the laser interferometer to project a laser line, and make the laser line pass through the light receiving area of ​​the light receiver assembly on the first-gear main bearing seat at the output end and the light receiving area of ​​the light receiver assembly on the first-gear main bearing seat at the free end. Adjust the longitudinal direction to the size of the main bearing seat to be measured according to the scale, and determine whether the end face position deviation of the main bearing seat is within ±3mm.

6. The laser marking method for a marine diesel engine base according to claim 4 or 5, characterized in that: In the step 2), the support point of the support head of the measuring support rod on the inner wall of the semi-axial hole of the main bearing seat is as close as possible to the opening edge of the semi-axial hole, and after installation, the light receiver is adjusted to a horizontal position using the level meter.

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