JPH0569660B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides a shaving cutter for finishing cutting the tooth surface of an automobile transmission gear, etc., and when the tooth surface is worn out due to repeated cutting, the tooth surface is removed. This invention relates to a shaving cutter tooth grinding method for grinding.

(Prior art) Conventionally, when finish cutting the tooth surface of a work gear such as a transmission gear for an automobile, for example,
In the method disclosed in Publication No. 131819, a shaving cutter is used, a slide base is provided that can be moved back and forth with respect to the placement position of the shaving cutter, and a work gear is placed on this slide base. According to the movement of the slide base, the work gear is engaged with the shaving cutter to cut its tooth surface. In order to prevent the cutting accuracy of this tooth surface from decreasing due to thermal deformation of the shaving cutter or changes in ambient temperature, the deviation between the actual measurement value of the work gear after cutting and its appropriate value is determined. A work gear cutting method is known in which the movement amount of the slide base is successively corrected according to the deviation value to maintain high cutting accuracy of the work gear.

(Problems to be Solved by the Invention) By the way, when the shaving cutter for cutting a work gear as described above becomes worn due to repeated cutting, the tooth surface must be ground before use. This process is repeated several times (for example, several dozen times), and this is effectively used to keep the product in use for a long time until it is new or discarded.

However, when a shaving cutter is re-ground and used many times, its tooth thickness gradually decreases each time it is re-ground. Since the meshing state of the shaving cutter changes, in order to obtain the proper tooth surface shape of the work gear, it is necessary to change the tooth surface shape of the shaving cutter little by little each time it is reground. For this reason, when the shaving cutter is in good condition (not worn out), it is possible to cut the work gear almost properly, but when the shaving cutter is worn out, the re-grinding work relies on humans, and it is difficult to use human intuition and advanced skills. This method requires a high degree of skill, making the re-grinding work difficult and time-consuming, and has the disadvantage that the tooth grinding accuracy of the shaving cutter (that is, the cutting accuracy of the work gear) cannot be compensated for as expected.

The present invention has been made in view of the above, and its purpose is to re-grind the shaving cutter many times to ensure that the tooth flank shape of the work gear is in the proper shape. By storing the target gear grinding data for each grinding in advance, the re-grinding work for each wear can be appropriately automated, eliminating the need for human touch or high level of skill, thus making the re-grinding work easier and easier. The objective is to sharpen the teeth of the shaving cutter in a short time and maintain high precision.

(Means for Solving the Problem) In order to achieve the above object, the solution method of the present invention is to remove the tooth surface of the shaving cutter every time the tooth surface of the shaving cutter is worn out due to cutting of the work gear. The premise is a method of grinding the teeth of a shaving cutter in which re-grinding is repeated multiple times. Then, within the usable range of the shaving cutter, a plurality of tooth grinding data according to the tooth surface condition such as tooth thickness is set and stored in advance, and the tooth surface condition of the shaving cutter is checked before grinding. The tooth surface of the shaving cutter is ground based on the grounding data that is close to the actual measured value and then the grounding data that is called out.

(Function) As described above, in the present invention, a plurality of tooth grinding data of the shaving cutter that makes the tooth surface shape of the work gear into an appropriate shape is set and stored in advance for each tooth surface condition such as various tooth thicknesses. Therefore, when re-grinding the tooth surface of a shaving cutter, the tooth grinding data corresponding to the tooth surface condition (tooth thickness, etc.) at that time is called up, and if re-grinding is performed based on this tooth surface data, the shaving cutter will be re-ground. The tooth surface shape of the Bing cutter can be easily ground in a short time according to this tooth grinding data. As a result, when cutting a work gear with the shaving cutter after re-grinding, the tooth surface shape of the work gear is formed into an appropriate shape regardless of the tooth thickness of the shaving cutter at that time, and the cutting accuracy is will be secured as scheduled.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

FIG. 1 shows an overall system diagram of a shaving cutter grinding device, in which 1 is a cutter grinding machine;
As shown in FIG. 2, the cutter grinding machine 1 uses a relatively small-diameter dish-shaped grindstone 1a to grind a shaving cutter A for cutting a work gear such as an automobile transmission gear when its tooth surface wears out. Through-grinding is performed to finish the entire tooth surface, and the tooth surface correction is performed by adjusting the axial position of the grindstone 1a by an amount corresponding to the amount of correction at each point on the path of the grindstone 1a.

Further, 2 is a gear cutting machine for experimentally finishing cutting the tooth surface of a work gear using the shaving cutter A ground by the cutter grinding machine 1, and
As shown in FIG. 3, the gear cutting machine 2 rotates the shaving cutter A in mesh with the work gear W at a predetermined axis intersection angle, thereby forming a shape on the tooth surface of the shaving cutter A. A large number of cutting grooves A1 as shown in FIG. ₄ are used to finish cutting the tooth surface of the work gear W. Furthermore, 3 is a three-dimensional measuring instrument, which measures the shaving cutter A ground by the cutter grinding machine 1 and the gear cutting machine 2.
This is a three-dimensional measurement of the tooth surface shape of a work gear W that has been subjected to test cutting.

In addition, 4 is a cutter grinding controller that controls the grinding operation of the shaving cutter A in the cutter grinding machine 1, and 5 is a cutter grinding controller 4 that transmits control information (about the tooth surface shape of the shaving cutter A). target value data)
6 is a measurement control computer that controls the tooth surface measurement operation in the three-dimensional measuring instrument 3, and 7 is a system control computer, which is the measurement control computer 6.
Receives measurement data of the tooth surface shape of the shaving cutter A after test grinding and the tooth surface shape of the work gear W from the machine, and causes the cutter grinding machine 1 to grind the shaving cutter A again according to each measurement data. For the cutter grinding control computer 5,
It outputs a target value signal for the tooth surface shape of the shaving cutter A.

Next, the procedure for grinding the tooth surface of the shaving cutter A (tooth grinding procedure) by the system control computer 7 will be explained based on the flowcharts shown in FIGS. 6 to 10. First, to explain the general flowchart shown in Fig. 6, information necessary for grinding the teeth of the shaving cutter A in step S _A , such as the specifications of the work gear W and the type of the shaving cutter A, is shown in Fig. 7. Create it based on the tooth grinding information creation flow and store it in a file. Next, in step S _B , the preparation work for tooth grinding, for example, the work of reading out the target value data of the tooth surface shape of the shaving cutter A to be ground from the file, is carried out based on the tooth grinding preparation work flow shown in Fig. 8. I will do it.

Then, in step S _C , the grinding information including target value data, etc. is transferred to the cutter grinding control computer 5, where the input information to the cutter grinding controller 4 is analyzed, and the information necessary for cutter grinding (target value data, etc.) to this cutter grinding controller 4, and perform trial grinding of the shaving cutter A with the cutter grinding machine 1 based on the trial grinding flow shown in FIG.
The shape of the tooth surface is measured with the three-dimensional measuring device 3, and the measurement is repeated until it falls within the tolerance range of the target shape. At this time, during this trial grinding, grinding information regarding the shaving cutters B to E to be ground next is sequentially transferred to the cutter grinding controller 4 via the cutter grinding control computer 5.

After that, when the tooth surface shape of the shaving cutter A falls within the allowable range of the target shape, in step S _D , the shaving cutter A that has been completely ground is removed based on the trial shaving flow shown in Fig. 10. The work gear W is subjected to trial shaving using the gear cutting machine 2, and the tooth surface shape of the work gear W after the trial shaving is measured using the three-dimensional measuring instrument 3. Return to S _B and repeat the grinding to correct the tooth surface shape of shaving cutter A. At that time, the target value of the tooth surface shape of the shaving cutter A is corrected according to the deviation between the actual measurement value of the work gear W and the target value, and the target value data at the time when it falls within the allowable range of the target shape is saved as a file. to be memorized.

Next, each flow shown in FIGS. 7 to 10 will be explained in detail. First, to explain the tooth grinding information creation flow shown in Fig. 7, after inputting the number and specifications of the shaving cutter tool and work gear W in step S _A1 , basic quantities are calculated and calculated in step S _A2 . Memorize. After that, work gear W is set in step S _A3 .
Create predetermined lattice points ξ _RW (I), ξ _LW (I), η _RW (J), η _LW (J) on the left tooth flank and right tooth flank as shown in Fig. 5, and store them in memory. At the same time, in step S _A4 , the standard for the tooth surface shape of the work gear W (target tooth surface shape) is determined.
Create C _RTW (I, J) and C _LTW (I, J) and store them in memory.

Then, in step S _A5 , shaving cutter A
Divide the tooth thickness reduction allowance during the life cycle into division allowances equal to the average grinding allowance for each re-grinding in advance, and calculate the divided tooth thickness Em (IT) (IT=1, 2
...), as well as the axis intersection angle Σ (IT) between the work gear W and the shaving cutter A, the generation generatrix intersection angle Φ (IT), the actual length of the line of action W _C (I), W _T (IT ),
Outer diameter d _KC (IT) of shaving cutter A, shift coefficient
x _NC (IT) etc. and store them in memory.

Next, shaving cutter A at step S _A6 .
Define the left and right tooth flank shape for each tooth thickness Em (IT) as the difference from the theoretical tooth flank (involute helicoidal surface), define this tooth flank shape on the tooth flank of work gear W, and Storage area C _RSC (I, J),
C Secure _LSC (I, J). Here, the reason why it is defined on the tooth surface of the work gear W is to reduce the memory capacity. In other words, shaving cutlet A
When defined by orthogonal coordinates (Xc, Yc) on the action surface of On the other hand, the points on the tooth surface of the work gear W are fixed regardless of the tooth thickness of the shaving cutter A, and the memory capacity can be reduced accordingly.

Finally, in step S _A7 , the angular tooth thickness Em (IT)
The target tooth surface shape data (initial value) of shaving cutter A is stored in the above memory areas C _RSC (I, J) and C _LSC .
A list of development state values F _{CS (IT) indicating whether the state (I, J) is already stored (hereinafter referred to as development state) is created, and initially each development state value F CS (} IT) is Initializes to "0" value and ends.

In addition, in the tooth grinding preparation work flow shown in FIG. 8, the target tooth surface shape of the shaving cutter A is read out or calculated in advance and determined. In other words, step
At step S _B1 , a work number (for example, a number indicating completion of tooth grinding, in progress, waiting state for tooth grinding, etc.) is created, and at step S _B2 , the shaving cutter tool number and the part number of the work gear W are input.

After that, in step S _B3 , input the current tooth surface condition (for example, the current value of tooth thickness) E _MCA of shaving cutter A, and in step S _B4 , enter the tooth thickness Emct closest to the list of tooth thickness Em (IT). Determine the tooth thickness number IT _C.

In addition, in step S _B5 , in advance, the lattice points ξ _RW
(I), ξ _LW (I), η _RW (J), η _LW (J), and the standard tooth surface C _RTW (I, J), C _LTW (I,
At the same time, in step S _B6 , the lattice points ξ _RC (k), ξ _LC (k) (K=1, M
+2), η _RC (L), η _LC (L) (L=1, N+2).

Then, from step S _B7 onwards, tooth surface shape data corresponding to the current tooth thickness of the shaving cutter A is read out from its storage areas C _RSC (I, J) and C _LSC (I, J). First, in step _{S B7} , the value of the development state value F _CS at the tooth thickness number IT _C that is closest to the current tooth thickness is determined. If the initial settings have already been made, enter the tooth thickness number IT _C in step S _B12 .
is stored in the memory area ITA, and in step S _B13 , the cutter target tooth surface shape for that tooth thickness number ITA is called from the memory areas C _RSC (I, J), C _LSC (I, J), and this cutter target tooth surface shape is The shaving cutter A is ground based on the shape.

If the development state value F _CS = 0 (if it has not been initialized), in order to initialize each tooth thickness sequentially, first set the developed state value F _CS = 1 in the tooth thickness list in step S _B8 . Determine whether there is a tooth thickness of , and if F _CS = 0 for all tooth thickness numbers,
Tooth thickness number closest to the current tooth thickness at step S _B3 IT _C
After storing in the memory area ITA, in step S _B10 , the target tooth flank shape data (predicted value) of the shaving cutter A at that tooth thickness is stored, the generation generatrix intersection angle Φ, and the actual length of the line of action at that tooth thickness. Calculate using W _C and W _T. Then, when the cutter target tooth flank shape is calculated using the predetermined tooth thickness number as described above and then modified as appropriate (described later), its development state value F _CS =1
Therefore, when creating target tooth flank shape data for other different tooth thicknesses, it is better to use the cutter target tooth flank shape data for the tooth thickness number in the above F _CS = 1 state. Since the accuracy is generally better than when using calculated values (predicted values), in step S _B11 , the tooth thickness Em of F _CS = 1 that is closest to the selected tooth thickness Emct in the tooth thickness list is selected.
After determining (ITA), in step S _B13 , the cutter target tooth flank shape data at the tooth thickness number ITA of that tooth thickness is stored in its storage area C _RSC (I, J), C _LSC
(I, J) and grind the shaving cutter A based on this cutter target tooth surface shape.

After that, use the above shaving cutter A.
Since the target tooth flank shape data is defined on the tooth flank of the work gear W, in order to capture this target tooth flank shape data on the working surface of the shaving cutter A, in step S _B14 , the shaving cutter A is Lattice points ξ _RC (k), ξ _LC (k), η _RC (L), η _LC (
L)
are mapped onto the left and right working surfaces of the work gear W, and by interpolation, the target tooth surfaces (target tooth surfaces) C _RTV (K, L), on the working surface of the shaving cutter A are mapped.
C _LTV (K, L) (K=1, M+2, L=1, N+
2) Determine.

Then, in step S _B15 , input tooth surface (target tooth surface data at each grid point) to the cutter grinding control computer 5 ξ _RC (k), ξ _LC (k), η _RC (L), η _L
C
(L), C _RIV (K, L), C _LIV (K, L) (C _RIV
(K, L)=C _RTV (K, L), C _LIV (K, L)=C _LTV
(K,L)) and step
In step S _B16 , input data for calculating the setting amount such as the axial stroke of the grinding wheel 1a of the cutter grinding machine 1 is created, and in step S _B17 , this data is transferred to the cutter grinding control computer, and the process ends. do.

Next, to explain the trial grinding flow shown in Fig. 9, in step S _C1 , the cutter grinder 1 is set to be ready for grinding, and in step S _C2 , the shaving cutter A is test-ground with this cutter grinder 1. .

After that, this shaving cutter A after grinding
is transferred to the three-dimensional measuring device 3, and in step S _C3 , the tooth surface shape of the shaving cutter A is measured in the cutting edge groove _A1 ...
The measured values are transferred to the system control computer 7 in step S _C4 , and then, in step S _C5 , each of the above measured values is calculated taking into account deviations from the set measurement points (grid points). Then, the measured values after correction are corrected to the values at each grid point, and the measured values after correction are converted into axis-perpendicular values t _RSC (K, L), t _LSC (K, L) (K=
2, M+1, L=2, N+1).

Then, in step S _C6 , each measured value t _RSC (K, L),
t Compare _LSC (K, L) with the target tooth surfaces C _RTV (K, L) and C _LTV (K, L) on the working surface of shaving cutter A set in step S _B14 in Fig. 8 above. Then, the tooth grinding error E _RSC (K, L), E _LSC (K,
L) (K=2, M+1, L=2, N+1), then determine whether this tooth grinding error is within the standard (within the allowable range), and if it is not within the standard, Step S _C8 sets the differential stroke Fx of cutter grinding machine 1 and the helix guide Fβ _MX.
After _calculating the setting amount _change values such _as
(K, L) (K=1, M+2, L=1, N+2) by changing the input values of shaving cutter A.
In order to re-grind, return to step S _B16 in FIG. 8 above. If the tooth grinding error is within the standard, the process proceeds to step S _C10 , in which all teeth of the shaving cutter A are ground, and then step S _C10 is performed.
When performing trial shaving of the work gear W using the shaving cutter A after completion of this grinding in S _C11 , the process proceeds to the trial shaving flow shown in FIG. 10.

Next, to explain the trial shaving flow shown in FIG. 10, in step S _D1 , the shaving cutter A after grinding is transferred to the gear grinding machine 2,
The work gear W is subjected to trial shaving using the gear grinding machine 2.

After that, in step S _D2 , the tooth surface shape of the work gear W is adjusted to the _lattice points ξ _RW (I), ξ _LW (I), η _RW (J), η _LW (J) set in step S B5 in Fig. 8 above. The measured values are transferred to the system control computer 7 in step S _D3 , and the measured values are converted into axis-perpendicular values t _RSW (I, J), t _LSW (I, J) in step S _D4 . Convert to

Then, in step S _D5 , each measured value t _RSW (I, J),
t Workpiece standard tooth surface corresponding to each _LSW (I, J)
Calculate the shape errors E _RSW (I, J) and E _LSW (I, J) by comparing C _RTW (I, J) and C _LTW (I, J),
In step S _D6 , the gear cutting machine 2 corrects the tooth surface shape error of the work gear W when the setting amount error of the cutter grinding machine 1 is corrected. Then, in step S _D7 , it is determined whether the tooth surface shape of the work gear W is within the standard based on this tooth surface shape error, and if it is not within the standard, a further step is performed.
S _D8 determines whether it is a trial based on the development status value F _CS = 1, and if F _CS = 1, it is determined that the setting of the cutter target tooth flank shape data (initial value) itself is incorrect. While an error is displayed, if F _CS = 0, the selected cutter target tooth flank shape data is corrected and the shaving cutter A is ground again, and the tooth flank shape error of the work gear W is corrected in step S _D9 . and the storage area depending on the grinding allowance per time.
After correcting the cutter target tooth surface shape data of C _RSC (I, J) and C _LSC (I, J), the shaving cutter A
Return to step S _B14 in Figure 8 to re-grind.
In addition, if the workpiece tooth surface is within the specifications in step S _D7 , it is determined in step S _D10 whether or not it is a trial based on the development status value F _CS =1 in the same way as above, and if Fcs = 0, , In Step S _D11 , the cutter target tooth flank shape data is corrected by the tooth flank shape error of the work gear W and the grinding allowance per grinding process in the same manner as in Step S _D9 above, and the cutter target tooth flank shape data after this correction is corrected in Step S. Tooth thickness number corresponding to _D12
ITA storage area C _RSC (I, J), C _LSC (I, J)
At the same time, the development state value F _CS in the tooth thickness number ITA is changed to the value "1", and the process ends.

Therefore, in the above embodiment, when cutting a large number of work gears W..., the gear cutting machine 2
The shaving cutter A is transferred to the shaving cutter A, and the meshing rotation of the shaving cutter A and the work gear W as shown in _FIG . .

Each time the tooth surface of the shaving cutter A wears out due to the cutting of the work gear W, the tooth surface is re-ground, and the shaving cutter A is used multiple times from when it was new to when it was discarded. It is repeatedly reused (approximately 30 times).

In that case, the tooth thickness of the shaving cutter A becomes thinner each time it is re-ground, and accordingly, the target tooth flank shape of the shaving cutter A that can cut the work gear W into the standard tooth flank shape also changes. However, the storage area for each pre-divided tooth thickness Em (IT) (IT=1, 2...)
C _RSC (I, J) and C _LSC (I, J) each have preset and stored cutter target tooth flank shape data that can cut the work gear W into a standard tooth flank shape. As a result, prior to re-grinding the shaving cutter A, the tooth surface condition (tooth thickness) of the shaving cutter A is measured, and the tooth thickness number closest to this actual measurement value is
ITC cutter target tooth surface shape data (tooth grinding data)
When the tooth surface of the shaving cutter A is ground with the cutter grinding machine 1 based on the cutter target tooth surface shape data called above, the tooth surface of the shaving cutter A will have the above-mentioned cutter target tooth surface shape. Since it is being ground, when this shaving cutter A is moved to the gear cutting machine 2 and the work gear W is automatically cut,
This work gear W is well cut into the standard tooth surface shape.

In addition, the cutter target tooth flank shape data (initial value) that is set and stored in advance for each tooth thickness is subject to the tooth flank shape error between the actual measurement value of the tooth flank shape of the work gear W during test cutting and its standard tooth flank shape, and Since it is corrected by the grinding allowance per turn, the initial value is highly accurate, and the tooth surface shape of the work gear W can be cut well.

Therefore, when re-grinding the shaving cutter A, the tooth surface shape can be automatically ground easily and quickly without human touch or high level of skill, and the standard teeth of the work gear W can be easily and quickly ground. High accuracy of tooth grinding of the shaving cutter A for obtaining the surface shape can be ensured regardless of the tooth surface condition (tooth thickness).

(Effects of the Invention) As explained above, according to the present invention, when re-grinding the tooth surface of a shaving cutter each time it wears out and reusing it multiple times, the work gear is cut into a standard tooth surface shape in advance. The tooth grinding data of the shaving cutter to be obtained is set for each tooth surface condition such as tooth thickness, the tooth surface condition of the shaving cutter is measured before re-grinding, and the data is recalled according to the tooth surface condition. Since the shaving cutter is automatically re-ground based on the grinding data, even if the tooth thickness changes each time the shaving cutter is re-ground, the work gear can always be cut accurately regardless of the tooth thickness. It can be re-ground to the desired tooth surface shape.
Regrinding work can be done easily and in a short time, and
High accuracy of tooth grinding of the shaving cutter can be ensured.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; Fig. 1 is an overall system diagram, Fig. 2 is an explanatory diagram showing how the shaving cutter is ground, and Fig. 3 is an illustration of the meshing of the shaving cutter with the work gear. An explanatory diagram of the state, FIG. 4 is an enlarged view of the main part showing the cutting edge groove of the shaving cutter, and FIG. 5 is an explanatory diagram of lattice points on the tooth surface. Figures 6 to 10 show the re-grinding flow of the shaving cutter, with Figure 6 showing the overall flow and Figure 7
The figure shows the tooth grinding information creation flow, Figure 8 shows the tooth grinding preparation work flow, Figure 9 shows the trial grinding flow, and Figure 10
The figure is a diagram showing a trial shaving flow. 1...Katsuta grinder, 2...Gear grinder, 3...
...Coordinate measuring instrument, 7...System control computer, A...Shaving cutter, W...Work gear.

Claims (1)

[Claims] 1. A method for grinding teeth of a shaving cutter, in which re-grinding of the tooth surface of the shaving cutter for cutting a work gear is repeated multiple times each time the tooth surface of the shaving cutter is worn out due to cutting of the work gear. Therefore, multiple tooth grinding data according to the tooth surface condition are set and stored in advance within the usable range of the shaving cutter, and the tooth surface condition of the shaving cutter is measured before grinding. A shaving cutter tooth grinding method characterized by calling tooth grinding data close to a value, and then grinding a tooth surface of a shaving cutter based on the called tooth grinding data.