Method for machining eccentric circle of double eccentric gear

Abstract

This invention relates to the field of double eccentric gear machining technology, and in particular to a method for machining the eccentric outer circle of a double eccentric gear. This method replaces the use of a lathe to align the eccentric outer circle reference by machining it on a boring and milling machine. Specifically, the highest point of the eccentric outer circle is first found using a boring and milling machine, and the line connecting this highest point and the center of the circle is made parallel to the machine tool coordinate system. Then, the actual center of the eccentric outer circle is determined using the machine tool coordinate system. The boring and milling machine allows the aligning reference to be transferred from one side to the other, eliminating the need to re-align the highest point of the eccentric outer circle during reverse machining; adjustments are made simply by using a horizontal dial indicator. This machining method simplifies the process, reduces machining errors, shortens machining time, and greatly improves machining efficiency.

Description

Technical Field

[0001] This invention relates to the field of double eccentric gear machining technology, specifically to a method for machining the eccentric outer circle of a double eccentric gear. Background Technology

[0002] Currently, the machining steps for machining the eccentric outer circle of an eccentric gear in existing technology are as follows:

[0003] (1) Positioning with the reference end face, with a positioning error of ≯0.01, and roughly adjust the eccentric outer circle to be concentric with the machine tool table;

[0004] (2) Phase adjustment: Place a section rod symmetrically across N teeth (N is an odd number of teeth for the highest point of eccentricity to the tooth tip, and N is an even number of teeth for the highest point of eccentricity to the tooth groove) on both sides of the eccentric plane to ensure that the readings of the dial indicator on the two sections of the rod are consistent and the error is ≤0.015. Finally, ensure that the center of the highest point of eccentricity is aligned with the center of the tooth groove or the tooth tip.

[0005] (3) Adjust the eccentricity: ① Test run the eccentric outer circle; ② Measure the eccentric outer circle dimension D, the bearing inner hole dimension d, and the thickness S of the lowest point of the eccentric outer circle and the bearing inner hole; ③ Eccentricity = D / 2 - d / 2 - S; ④ Calculate that the eccentricity is within the required range.

[0006] Normally, eccentric gears need to be machined in groups, and the eccentricity error and phase error of the same group of eccentric gears are generally required to be ≤0.02. However, products obtained using the above machining method are difficult to meet these requirements in practice after subsequent testing, and the errors of some eccentric gears may even far exceed the requirements.

[0007] The reasons for the above problems, after repeated research by the inventors' team, mainly include the following aspects:

[0008] (1) When adjusting the phase, a pitch bar needs to be placed. Placing the pitch bar requires hand operation, especially when it is placed on the helical teeth. It is not easy to place it steadily by hand, which can easily cause errors.

[0009] (2) Adjusting the phase requires the vertical car to rotate discontinuously. When the vertical car starts suddenly, there will be a certain inertial impact. When the dial indicator is off-center on the outer circle, the dial indicator needle will shake and the reading will be inaccurate.

[0010] (3) Adjusting the eccentricity using the above method requires multiple wall thickness measurements. The measurement positions will not be exactly the same in multiple measurements, so the measurement results are prone to differences.

[0011] For machining double eccentricity, the above-mentioned phase adjustment and eccentricity adjustment need to be performed twice as many times; moreover, during double eccentricity machining, not only will the above-mentioned problems exist on the outer eccentricity of each side, but the coaxiality of the outer eccentricity of the two sides will also be difficult to guarantee.

[0012] Therefore, designing and developing a machining method for the eccentric outer circle of a double eccentric gear that is easy to process and has small errors has become one of the urgent problems to be solved in this field. Summary of the Invention

[0013] The purpose of this invention is to provide a machining method for the eccentric outer circle of a double eccentric gear, so as to solve the problems of unavoidable human error in alignment, measurement and machining in existing machining technologies.

[0014] To achieve the above objectives, the present invention provides the following technical solution:

[0015] A method for machining the eccentric outer circle of a double eccentric gear involves using a boring and milling machine to locate the center of the eccentric outer circle and to achieve datum transfer. The datum for machining the eccentric outer circle on the boring and milling machine is used as the datum when machining the eccentric outer circle on a vertical lathe.

[0016] This includes a reference method for turning and aligning machining on a boring and milling machine, specifically:

[0017] 1) Mill the contour pad flat, and use the reference end face of the eccentric wheel large gear for positioning. Use a 0.02 feeler gauge to check the gap between the end face and the contour pad. If it is not too large, find the "0" mark tooth tip or tooth groove. Use two pitch round bars to symmetrically span an odd or even number of teeth with the center of the tooth tip or tooth groove as the reference. On the machine tool, align the line connecting the centers of the two pitch round bars with the X-axis direction of the machine tool to ensure that the coordinate values ​​of the left and right phases are consistent.

[0018] 2) Mill a leveling band on the steel plate welded to the eccentric counterweight block at the non-reference end of the eccentric gear, deep enough for a dial indicator to be used.

[0019] This also includes a method for machining eccentric outer diameter datums on a boring and milling machine, which includes boring the eccentric outer diameter datum at the non-datum end and boring the eccentric outer diameter datum at the datum end.

[0020] The boring of the non-reference end eccentric outer circle reference is specifically as follows: based on the center of the inner hole of the non-reference end bearing, the corresponding eccentricity is offset in the eccentric direction, and a alignment zone is bored at the upper end of the eccentric outer circle.

[0021] The eccentric outer circle reference of the boring reference end is specifically:

[0022] Adjust the surface and check that the runout of the contour pad is less than 0.01. Position the large eccentric gear with the non-reference end face. Use a 0.02 feeler gauge to check that the gap between the end face and the contour pad is not excessive. Adjust the dial indicator on the steel plate on the side of the non-reference end face so that the dial indicator is parallel to the X-axis coordinate of the machine tool. Ensure that the coordinate values ​​of the left and right phases are consistent. Fix the large eccentric gear on the worktable.

[0023] Based on the center of the inner hole of the reference end bearing, offset the corresponding eccentricity in the eccentric direction, and bore a alignment band at the upper end of the eccentric outer circle of the reference end.

[0024] Compared with the prior art, the beneficial effects of the present invention are:

[0025] (1) The machining method of the present invention uses a boring and milling machine to find the center of the eccentric outer circle and to realize the reference transfer, which replaces the previous machining method using a lathe.

[0026] (2) The highest point of the eccentric outer circle can be accurately found by boring and milling machines; moreover, the eccentricity can be precisely controlled by boring and milling machines, rather than by measuring the inner wall thickness of the bearing bush by finding the lowest point of eccentricity.

[0027] (3) By using the milling machine to find the alignment datum of the reverse side, there is no need to find the highest point of the eccentric outer circle during the subsequent reverse side machining.

[0028] (4) The datum of the eccentric outer circle can be directly milled out by the boring and milling machine, and the highest point of the eccentric outer circle does not need to be found in the subsequent vertical lathe machining.

[0029] (5) The machining method of the present invention uses a boring and milling machine to machine the eccentric outer circle reference, saving one boring and milling machine operation. Because the end face of the eccentric wheel needs to be machined with a threaded hole, and this threaded hole has an angular relationship with the eccentric outer circle, according to the previous machining method, the eccentric outer circle must be machined to the finished product first, the center of the eccentric outer circle is confirmed, and then the end face threaded hole with the center of the eccentric outer circle as the reference is machined; however, the machining method of the present invention can directly confirm the center of the eccentric outer circle through the boring and milling machine program and thus machine the eccentric outer circle reference, so the end face threaded hole can be machined at the same time.

[0030] (6) The present invention uses a boring and milling machine to process the eccentric outer circle reference, which avoids the dial indicator shaking and inaccurate reading caused by the sudden start of the vertical lathe and discontinuous operation; the dial indicator is more accurate.

[0031] (7) In the past, when adjusting the eccentricity of the eccentric wheel, it was necessary to repeatedly measure the eccentricity at the lowest point and the thickness P of the inner hole of the bearing bush to adjust the eccentricity. However, the present invention uses a boring and milling machine to process the eccentric outer circle reference, and directly specifies the eccentricity through machine tool programming, avoiding measurement errors. Under the condition that the repeatability of the boring and milling machine is consistent, the eccentricity of the same group of eccentric wheels is consistent, and the eccentricity of both sides of the double eccentric eccentric wheels is consistent.

[0032] (8) In the past, when machining double eccentric outer circles, it was necessary to align the phase twice, which resulted in the aforementioned dial indicator reading error. The two alignment errors multiplied the workpiece phase error. The present invention uses a boring and milling machine to machine double eccentric outer circles, which only requires one phase alignment. When machining the first side eccentric outer circle reference, after adjusting the phase, an alignment band is milled on the steel plate near the eccentric body. This operation is equivalent to transferring the phase reference of one side eccentricity to the steel plate. When flipping to machine the other side eccentric outer circle reference, the alignment band on the steel plate can be directly aligned, avoiding the error caused by repeated phase alignment. Alternatively, the steel plate can be removed and the machine can be directly machined on the boring and milling machine. When flipping to machine, only the worktable needs to be rotated 180°.

[0033] In summary, the processing method provided by this invention greatly reduces machine tool processing time and worker alignment time; it also greatly reduces alignment errors and processing errors. Attached Figure Description

[0034] Figure 1 A schematic diagram of the clamping of a double eccentric gear boring and milling machine;

[0035] Figure 2 for Figure 1 A schematic diagram of direction "A" in the middle;

[0036] Figure 3 A schematic diagram for boring the eccentric outer circle datum at the non-datum end and milling the alignment datum;

[0037] Figure 4 for Figure 3 A schematic diagram of direction "A" in the middle;

[0038] Figure 5 for Figure 3 A magnified view of a portion of the image;

[0039] Figure 6 for Figure 4 A magnified view of a portion of the image;

[0040] Figure 7 This is a schematic diagram of the eccentric outer circle reference at the boring reference end;

[0041] Figure 8 for Figure 7 A schematic diagram of the "B" direction in the middle;

[0042] Figure 9 The image shows a photograph of a processed object using the processing method of this invention.

[0043] Among them, 1-non-datum end eccentric outer circle, 2-datum end eccentric outer circle, 3-datum end bearing inner hole, 4-non-datum end bearing inner hole, 5-bearing, 6-eccentric wheel large gear datum end face, 7-eccentric wheel large gear non-datum end face, 8-eccentric body counterweight block, 9-steel plate, 10-aligning belt, 11-tooth tip, 12-section round bar, 13-eccentricity, 14-eccentric high point, 15-eccentric outer circle center, 16-bearing center, 17-eccentric low point, 18-worktable, 19-square equal height pad, pressure plate-20, screw-21, nut-22, 23-cylindrical equal height pad, 24-eccentric wheel large gear. Detailed Implementation

[0044] 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, and 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.

[0045] Combination Figure 1-8 As shown, a method for machining the eccentric outer circle of a double eccentric gear comprises the following steps:

[0046] (1) Spot welding

[0047] 1) Weld a steel plate 9 onto the eccentric counterweight block 8 on the non-reference end face 7 of the eccentric gear, place it horizontally in the center, and be perpendicular to the line connecting the center 15 of the eccentric outer circle and the center 16 of the bearing bush.

[0048] 2) Spot welding ensures a strong weld;

[0049] (2) Clamping

[0050] 1) Pre-erect two worktables 18 on the boring and milling machine and fix them on the machine tool. At the corresponding position of the worktable on which the reference end face 6 of the eccentric wheel large gear is to be positioned, fix two cylindrical equal height pads 23 by screws 21 and nuts 22, and then mill them flat.

[0051] 2) Place a square equal-height pad 19 under the large eccentric gear where the eccentric wheel will be placed, and fix it on the machine tool in advance;

[0052] (3) Milling the reference for turning and aligning.

[0053] 1) The eccentric gear 24 sits on a square leveling pad. The reference end face 6 of the eccentric gear is positioned on a cylindrical leveling pad 23. Use a 0.02 feeler gauge to check the gap between the reference end face 6 of the eccentric gear and the cylindrical leveling pad 23. If the gap is not found, find the "0" mark tooth tip 11 (or tooth groove). Use two pitch round bars 12 with the center of tooth tip 11 (or tooth groove) as the reference, symmetrically spanning an odd (or even) number of teeth. On the machine tool, align the line connecting the centers of the two pitch round bars 12 with the X-axis direction of the machine tool to ensure that the coordinate values ​​of the left and right phases are consistent. Use four pressure plates 20, and fix the eccentric gear 24 on the worktable 18 through screws 21 and nuts 22.

[0054] 2) Mill a leveling band 10 on the steel plate 9, ensuring that the depth is sufficient for leveling.

[0055] (4) Boring the eccentric outer circle of the non-datum end 1 datum

[0056] Based on the center of the inner hole 4 of the non-reference end bearing, offset the corresponding eccentricity by 13 in the eccentric direction, and bore a section of alignment zone on the upper end of the eccentric outer circle 1 of the non-reference end until it is exposed to light.

[0057] (5) Boring the eccentric outer circle of the reference end 2 reference

[0058] 1) Adjust the surface and check that the runout of the contour pad is less than 0.01. Position the eccentric gear with the non-reference end face 7. Use a 0.02 feeler gauge to check that the gap between the end face and the contour pad is not excessive. Make the dial indicator on the non-reference end face side steel plate 9 parallel to the X-axis coordinate of the machine tool to ensure that the coordinate values ​​of the left and right phases are consistent. Use four pressure plates 20 to fix the eccentric gear 24 on the worktable 18 through screws 21 and nuts 22.

[0059] 2) Based on the center of the inner hole 3 of the reference end bearing, offset the corresponding eccentricity by 13 in the eccentric direction, and bore a section of alignment band on the upper end of the eccentric outer circle 2 of the reference end until it is exposed to light.

[0060] Photos of the actual objects processed using the above methods are shown below. Figure 9 As shown.

[0061] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for machining the eccentric outer circle of a double eccentric gear, characterized in that: The process of finding the center of the eccentric outer circle and transferring the reference point using a boring and milling machine includes the following steps: (1) Spot welding A steel plate is welded onto the counterweight block of the eccentric body at the non-reference end of the eccentric gear, and placed horizontally in the center, perpendicular to the line connecting the center of the outer circle of the eccentric gear and the center of the bearing bush. (2) Clamping Two worktables are pre-erected on the boring and milling machine and fixed on the machine tool. At the corresponding position of the worktable on which the reference end face of the eccentric wheel large gear is to be positioned, two cylindrical equal-height pads are fixed and then milled flat. Place a square, level pad under the large eccentric gear where the eccentric wheel will be placed, and fix it to the machine tool in advance; (3) Milling the reference for turning over and aligning The eccentric gear sits on a square leveling pad, and the reference end face of the eccentric gear is positioned on a cylindrical leveling pad. Use a 0.02 feeler gauge to check the gap between the reference end face and the cylindrical leveling pad. If it is not too large, find the "0" mark on the tooth tip or tooth groove. Use two pitched round bars with the center of the tooth tip or tooth groove as the reference, symmetrically spanning an odd or even number of teeth. On the machine tool, align the line connecting the centers of the two pitched round bars with the X-axis direction of the machine tool to ensure that the coordinate values ​​of the left and right phases are consistent. Fix the eccentric gear on the worktable. Mill a alignment band into the steel plate, ensuring the depth is sufficient for alignment. (4) Boring the eccentric outer circle datum at the non-datum end Based on the center of the inner hole of the non-reference end bearing, offset the corresponding eccentricity in the eccentric direction, and bore a section of alignment zone at the upper end of the eccentric outer circle of the non-reference end until it is exposed to light. (5) Boring the eccentric outer circle reference end Adjust the surface and check that the runout of the contour pad is less than 0.

01. Position the large eccentric gear with the non-reference end face. Use a 0.02 feeler gauge to check that the gap between the end face and the contour pad is not excessive. Adjust the dial indicator on the steel plate on the side of the non-reference end face so that the dial indicator is parallel to the X-axis coordinate of the machine tool. Ensure that the coordinate values ​​of the left and right phases are consistent. Fix the large eccentric gear on the worktable. Based on the center of the inner hole of the reference end bearing, offset the corresponding eccentricity in the eccentric direction, and bore a alignment band at the upper end of the eccentric outer circle of the reference end until it is exposed to light.

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