CN111097977A - Theoretical error-free indexing method and gear dividing mechanism for gear machining - Google Patents
Theoretical error-free indexing method and gear dividing mechanism for gear machining Download PDFInfo
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- CN111097977A CN111097977A CN201911381447.7A CN201911381447A CN111097977A CN 111097977 A CN111097977 A CN 111097977A CN 201911381447 A CN201911381447 A CN 201911381447A CN 111097977 A CN111097977 A CN 111097977A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23F—MAKING GEARS OR TOOTHED RACKS
- B23F23/00—Accessories or equipment combined with or arranged in, or specially designed to form part of, gear-cutting machines
- B23F23/08—Index mechanisms
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23F—MAKING GEARS OR TOOTHED RACKS
- B23F23/00—Accessories or equipment combined with or arranged in, or specially designed to form part of, gear-cutting machines
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23F—MAKING GEARS OR TOOTHED RACKS
- B23F23/00—Accessories or equipment combined with or arranged in, or specially designed to form part of, gear-cutting machines
- B23F23/08—Index mechanisms
- B23F23/085—Index mechanisms of the continuous type
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Abstract
一种齿轮加工的无理论误差分度方法，具体包括以下步骤：S1：判断被加工齿轮所处的加工状态，齿槽加工状态时进行步骤2，需分齿时则进行步骤4；S2：启动数控机床主轴，其旋转运动由输入轴传递给齿2，齿2按照1:1的传动比传递给齿3；S3：分齿运动离合器松开，齿4空转，螺旋运动离合器闭合，运动由齿8传给齿9，并进入步骤6；S4：停止数控机床主轴运动，分齿运动离合器闭合，螺旋运动离合器松开；S5：启动数控机床主轴的旋转运动，运动由齿4传递给齿6，并进入步骤6；S6：输出从动齿轮经运动输出轴传递给待加工齿轮控制其旋转或分度。本发明结构简单，支持齿轮螺旋和分度，运作流畅方便；分度操作直接便捷，精度高，无理论误差。
A theoretical error-free indexing method for gear machining, which specifically includes the following steps: S1: judging the machining state of the gear to be machined, performing step 2 when the cogging machining state is performed, and performing step 4 when teeth need to be divided; S2: starting CNC machine tool spindle, its rotational motion is transmitted to tooth 2 by the input shaft, and tooth 2 is transmitted to tooth 3 according to the transmission ratio of 1:1; S3: The split-tooth motion clutch is released, tooth 4 is idling, the screw motion clutch is closed, and the motion is transmitted by the tooth 8 is passed to tooth 9, and goes to step 6; S4: Stop the movement of the spindle of the CNC machine tool, the gear-splitting clutch is closed, and the helical motion clutch is released; S5: Start the rotation of the spindle of the CNC machine tool, and the movement is transmitted from tooth 4 to tooth 6, And go to step 6; S6: the output driven gear is transmitted to the gear to be processed through the motion output shaft to control its rotation or indexing. The invention has a simple structure, supports gear helix and indexing, and operates smoothly and conveniently; the indexing operation is direct and convenient, the precision is high, and there is no theoretical error.
Description
Technical Field
The invention relates to the technical field of gear machining, in particular to a theoretical error-free indexing method and a gear dividing mechanism for gear machining.
Background
When the semi-generating method is used for processing gears such as spiral internal teeth, herringbone teeth and the like, a cutter is used for processing a single tooth groove or a plurality of tooth grooves, and then the gear to be processed needs to be rotationally indexed for processing the next tooth groove or a plurality of next tooth grooves.
Generally, the indexing head of the gear-dividing mechanism is 1:40, namely 40 circles of a handle, the indexing head rotates for 1 circle, and if the number of required milling teeth is not an integral multiple of 40, an indexing disc which is integral multiple of the number of teeth needs to be selected to further confirm the number of rotating holes. If there is no index plate or the number of teeth cannot be evenly divided by 360 °, the rotation angle cannot be confirmed, which seriously affects the gear machining accuracy and has an error even in the index plate.
In addition to using the index plate to perform indexing accurately, a servo control method is also commonly used to control a gear to be machined to rotate for a fixed integer angle each time and then perform cogging machining, the indexing method distributes errors to each tooth and eliminates accumulated errors of the corresponding angle of each tooth, but obviously, the indexing method theoretically has certain errors.
Therefore, it is necessary to design a gear-dividing mechanism with controllable precision of rotary indexing and simple operation according to the motion requirement of the semi-generating method, and to design an indexing method without theoretical error.
Disclosure of Invention
In order to solve the technical problems, the invention provides a theoretical error-free indexing method and a gear dividing mechanism for gear machining.
The invention adopts the following specific technical scheme:
a theoretical error-free indexing method for gear machining specifically comprises the following steps:
s1: judging the machining state of the machined gear, performing the step 2 when the machined gear is in a tooth groove machining state, and performing the step 4 when the machining of one tooth groove is finished and the tooth division is needed to perform the machining of the next tooth groove;
s2: starting a numerical control machine tool spindle, wherein the rotary motion of the numerical control machine tool spindle is transmitted to a machine tool spindle motion input driving gear through an input shaft, and the machine tool spindle motion input driving gear is transmitted to a machine tool spindle motion output driven gear according to a transmission ratio of 1: 1;
s3: the tooth separation motion clutch is loosened, tooth separation motion input driving gears idle, the spiral motion clutch is closed, motion is transmitted to spiral motion output driven gears through the spiral motion input driving gears, and the step 6 is carried out;
s4: stopping the movement of the main shaft of the numerical control machine tool, closing the tooth-dividing movement clutch and loosening the spiral movement clutch;
s5: starting the rotation motion of the main shaft of the numerical control machine tool, transmitting the motion from the tooth separation motion input driving gear to the tooth separation motion output driven gear, and entering the step 6;
s6: the output driven gear is transmitted to the gear to be processed on the fixed clamp through the motion output shaft to control the rotation or the graduation of the gear.
Preferably, the tooth-division motion input driving gear and the spiral motion input driving gear are sleeved on the shaft in an idle mode, and the machine tool spindle motion input driving gear, the machine tool spindle motion output driven gear, the tooth-division motion output driven gear and the spiral motion output driven gear are fixed on the shaft.
Preferably, the rotation of the tooth separation motion input driving gear and the rotation of the spiral motion input driving gear are controlled by opening and closing the tooth separation motion clutch and the spiral motion clutch respectively.
Preferably, the machine tool spindle motion input driving gear and the machine tool spindle motion output driven gear, the tooth division motion input driving gear and the tooth division motion output driven gear, and the spiral motion input driving gear and the spiral motion output driven gear are respectively meshed with each other.
Preferably, the three pairs of intermeshing gears are equidistant from center to center.
Preferably, the transmission ratio of the spiral motion input driving gear to the spiral motion output driven gear is 1: 1.
Preferably, the number of teeth of the tooth-division motion output driven gear is integral multiple of the number of teeth of the gear to be machined.
Preferably, the number of teeth of the input driving gear of the tooth division motion is a divisor of 360, and the quotient is a rational number.
A gear dividing mechanism of a gear dividing mechanism without theoretical error for gear machining comprises a clamp transmission structure in the method.
The invention has the beneficial effects that:
(1) the structure is simple, the gear is supported to perform spiral and indexing motion, and the operation is smooth and convenient;
(2) the indexing operation is direct and convenient, the precision is high, and no theoretical error exists.
Drawings
FIG. 1 is a flow chart of a theoretical error indexing method of the present invention;
FIG. 2 is a schematic view of a transmission structure of a clamp inside a machine tool of the gear-dividing mechanism of the invention;
FIG. 3 is a schematic view of the machine tool structure of the gear-dividing mechanism of the present invention.
1. An input shaft; 2. a driving gear is input by the motion of a machine tool spindle; 3. the machine tool spindle moves to output a driven gear; 4. the gear-division motion is input into a driving gear; 5. a split gear movement clutch; 6. the tooth-separating motion outputs a driven gear; 7. a screw motion clutch; 8. a helical motion input drive gear; 9. a screw motion output driven gear; 10. and a motion output shaft.
Detailed Description
The invention is further illustrated by the following specific examples. The starting materials and methods employed in the examples of the present invention are those conventionally available in the market and conventionally used in the art, unless otherwise specified.
Example 1
As shown in fig. 2 and 3, according to the motion requirement of machining a spiral/herringbone gear, a tooth dividing mechanism of a tooth dividing mechanism without theoretical error for gear machining is designed, which comprises three pairs of gears which are meshed with each other and comprise a machine tool spindle motion input driving gear (2) and a machine tool spindle motion output driven gear (3), a tooth dividing motion input driving gear (4) and a tooth dividing motion output driven gear (6) and a spiral motion input driving gear (8) and a spiral motion output driven gear (9), wherein the center distances of the three pairs of gears which are meshed with each other are respectively equal, and meanwhile, the transmission ratios of the machine tool spindle motion input driving gear (2) to the machine tool spindle motion output driven gear (3), the spiral motion input driving gear (8) to the spiral motion output driven gear (9) are all 1: 1.
The gear-dividing motion input driving gear (4) and the spiral motion input driving gear (8) are sleeved on the shaft in a hollow mode, the machine tool spindle motion input driving gear (2), the machine tool spindle motion output driven gear (3), the gear-dividing motion output driven gear (6) and the spiral motion output driven gear (9) are fixed on the shaft, and the gear-dividing motion input driving gear (4) and the spiral motion input driving gear (8) are controlled to rotate or not by opening and closing of the gear-dividing motion clutch (5) and the spiral motion clutch (7) respectively.
The number of teeth of the minute tooth motion output driven gear (6) is integral multiple of the number of teeth of the gear to be processed, the number of teeth of the minute tooth motion input driving gear (4) is used as a divisor of 360, and the quotient is a rational number.
If the number of teeth of the gear to be processed is 17, set up that the number of teeth of the fractional tooth motion input driving gear (4) is 20 (the divisor quotient of 360 is 18, for rational number, satisfy the design requirement), number of teeth 17 can't be divided by 360 in order to confirm specific rotation angle, consequently according to above-mentioned requirement, usable generation method processes out the number of teeth and waits to process 1 times of the number of teeth of the gear and with the fractional tooth motion output driven gear (6) of the meshing of the fractional tooth motion input driving gear (4), then the number of teeth is 17 equally. According to the principle of gear meshing, the tooth separation motion input driving gear (4) rotates by 18 degrees, namely, one tooth is rotated, the tooth separation motion output driven gear (6) also necessarily rotates by one tooth, namely, the tooth separation motion output driven gear can accurately rotate by (360/17) degrees, so that the degree corresponding to one tooth of the gear to be processed is controlled to rotate, the accurate division motion is realized, and no theoretical error exists.
Example 2
As shown in fig. 1, a theoretical error-free indexing method based on the tooth separation mechanism of embodiment 1 specifically includes the following steps:
step 1: judging the machining state of the machined gear, performing the step 2 when the machined gear is in a tooth groove machining state, and performing the step 4 when the machining of one tooth groove is finished and the tooth division is needed to perform the machining of the next tooth groove;
step 2: starting a main shaft of the numerical control machine tool, wherein the rotary motion of the main shaft is transmitted to a machine tool main shaft motion input driving gear (2) through an input shaft (1), and the machine tool main shaft motion input driving gear (2) is transmitted to a machine tool main shaft motion output driven gear (3) according to a transmission ratio of 1: 1;
and step 3: the tooth separation motion clutch (5) is released, the tooth separation motion input driving gear (4) idles, the spiral motion clutch (7) is closed, the motion is transmitted to the spiral motion output driven gear (9) by the spiral motion input driving gear (8), and the step 6 is carried out;
and 4, step 4: stopping the motion of a main shaft of the numerical control machine tool, closing the gear-dividing motion clutch (5), loosening the spiral motion clutch (7), and inputting a driving gear (8) into spiral motion to idle;
and 5: starting the rotation motion of a main shaft of the numerical control machine tool, controlling the tooth division motion input driving gear (4) to rotate a tooth groove, transmitting the motion to the tooth division motion output driven gear (6), controlling the tooth division motion output driven gear (6) to rotate a tooth groove, and entering step 6;
step 6: the output driven gear (9 or 6) is transmitted to the gear to be processed on the fixed clamp through the motion output shaft (10) to control the rotation or the graduation of the gear.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.
Claims (9)
1. A theoretical error-free indexing method for gear machining specifically comprises the following steps:
s1: judging the machining state of the machined gear, performing the step 2 when the machined gear is in a tooth groove machining state, and performing the step 4 when the machining of one tooth groove is finished and the tooth division is needed to perform the machining of the next tooth groove;
s2: starting a main shaft of the numerical control machine tool, wherein the rotary motion of the main shaft is transmitted to a machine tool main shaft motion input driving gear (2) through an input shaft (1), and the machine tool main shaft motion input driving gear (2) is transmitted to a machine tool main shaft motion output driven gear (3) according to a transmission ratio of 1: 1;
s3: the tooth separation motion clutch (5) is released, the tooth separation motion input driving gear (4) idles, the spiral motion clutch (7) is closed, the motion is transmitted to the spiral motion output driven gear (9) by the spiral motion input driving gear (8), and the step 6 is carried out;
s4: stopping the motion of the main shaft of the numerical control machine tool, closing the tooth-dividing motion clutch (5), and loosening the spiral motion clutch (7);
s5: starting the rotation motion of a main shaft of the numerical control machine tool, transmitting the motion to a tooth separation motion output driven gear (6) by a tooth separation motion input driving gear (4), and entering the step 6;
s6: the output driven gear (9 or 6) is transmitted to the gear to be processed on the fixed clamp through the motion output shaft (10) to control the rotation or the graduation of the gear.
2. The indexing method without theoretical errors according to claim 1, wherein the indexing gear (4) with indexing motion and the driving gear (8) with helical motion are fitted on the shaft, and the machine spindle motion input driving gear (2), the machine spindle motion output driven gear (3), the indexing motion output driven gear (6) and the driven gear (9) with helical motion are fixed on the shaft.
3. The rational-error-free indexing method according to claim 2, wherein the indexing-motion input driving gear (4) and the spiral-motion input driving gear (8) are controlled to rotate or not by opening and closing of the indexing-motion clutch (5) and the spiral-motion clutch (7), respectively.
4. The indexing method without theoretical errors according to claim 1 or 2, characterized in that the machine spindle motion input driving gear (2) and the machine spindle motion output driven gear (3), the indexing motion input driving gear (4) and the indexing motion output driven gear (6), and the screw motion input driving gear (8) and the screw motion output driven gear (9) are respectively engaged with each other.
5. The method of claim 4, wherein the three pairs of intermeshing gears are equidistant from center to center.
6. The method of claim 4, wherein the ratio of the helical motion input driving gear (8) to the helical motion output driven gear (9) is 1: 1.
7. A method of indexing without theoretical errors according to claim 4, wherein the number of teeth of the indexing motion output driven gear (6) is an integer multiple of the number of teeth of the gear to be machined.
8. A method of indexing without theoretical errors according to claim 4, wherein the number of teeth of the indexing motion input drive gear (4) is a divisor of 360, and the quotient is a rational number.
9. A gear indexing mechanism without theoretical error for gear machining, comprising the clamp transmission structure in the method of any one of claims 1 to 8.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911381447.7A CN111097977B (en) | 2019-12-27 | 2019-12-27 | A theoretical error-free indexing method for gear machining and a gear-separating mechanism |
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| CN201911381447.7A CN111097977B (en) | 2019-12-27 | 2019-12-27 | A theoretical error-free indexing method for gear machining and a gear-separating mechanism |
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