JP2513872B2 - Tooth surface shape correction device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a tooth surface shape correcting device for correcting the tooth surface shape of a gear to a desired shape.

(Prior Art) Conventionally, in order to finish the tooth surface shape of a gear into a desired shape,
First, the tooth of the gear as a work is cut into a rough shape by a gear cutting machine, and then the tooth surface of this gear is measured under a predetermined coordinate system, and the obtained measurement data and design data are compared. In order to obtain a correction amount that substantially matches the two data, it is common to adjust the relative positional relationship between the tooth surface shape correction device and the gear, for example, by manual adjustment, and polish the tooth surface in this state. there were.

(Problems to be solved by the invention) However, when the above-mentioned method of manual adjustment is adopted, an operator performs manual adjustment based on experience and the like, so that polishing-measurement is performed many times until desired processing accuracy is obtained. -It is necessary to repeat the adjustment process, which consumes a great deal of work time. Even if adjustments are made to achieve the desired machining accuracy, if the rod changes, the processing tendency of the gears on the gear cutting machine (eg, crowning amount, crowning center) also changes, so manual adjustments must be performed each time. I have to. Further, even if the adjustment is performed to obtain the desired machining accuracy, the relative positional relationship between the work and the whetstone will differ due to the wear of the whetstone at the beginning of polishing and after polishing a large number of works. If the wear of the grindstone is not corrected, the desired processing accuracy cannot be secured.

The present invention adjusts the relative positional relationship between the grinding wheel and the gear by setting the linear movement amount and the rotation amount of the crowning cam based on the comparison between the measurement data of the tooth flank of the gear and the design data. The purpose is to solve.

(Means for Solving the Problem) For this purpose, the tooth surface shape correcting device of the present invention is, as the concept is shown in FIG. 1, a swing table that regulates a grindstone and a relative positional relationship between the grindstone and a gear. A crowning cam connected to the swing table, a linear moving means for linearly moving the reclining cam, a rotating means for rotating the crowning cam, a linear movement amount of the linear moving means, and the rotation. It is characterized in that the rotation amount of the gear is set based on the comparison between the measurement data of the gear and the design data, and the tooth surface shape of the gear is corrected.

(Operation) According to the present invention, the setting means sets the linear movement amount of the linear movement means and the rotation amount of the rotation means based on the comparison between the measurement data of the gear as the work and the design data. The crowning cam is linearly moved by the amount of linear movement, and the rotating means rotates the crowning cam by this amount of rotation, and this crowning cam is connected to the swing table, and this swing table has a relative positional relationship between the grindstone and the gear. Therefore, when the swing table swings during the tooth surface shape correction processing, the gear wheel moves along the locus of the above linear movement and rotation with respect to the grindstone, and thus along the curve corresponding to the tooth surface shape. By applying a rotational force in the same rotational direction between the grindstone and the gear as it moves, the contact area between the two is abraded and the desired tooth surface shape is obtained. You.

In this way, the amount of movement of the crowning cam is appropriately set according to the actual tooth surface shape, and the tooth surface shape correction device is automatically adjusted so that the desired tooth surface shape satisfying the predetermined processing accuracy can always be obtained. It is possible to eliminate troublesome manual adjustment and readjustment every time the rod is changed. Further, by correcting the amount of wear of the grindstone in the setting of the amount of movement of the crowning cam, it is possible to ensure the desired processing accuracy even when the tooth surfaces of many gears are corrected.

(Example) Hereinafter, the Example of this invention is described in detail based on drawing.

FIG. 2 is a diagram showing the overall configuration of the first embodiment of the tooth surface shape correcting device of the present invention. The tooth surface shape correction device 10 has a mechanical portion 10.
The mechanical unit 10a includes a swing table 11, a slide table 12, a crowning cam mechanism 13, and a control unit 10b.
The work measuring device 30 is provided.

A work clamp device and a work rotating device, not shown here, are fixed to the upper surface of the swing table 11, and the swing table 11 performs grinding of a gear as a work clamped by the work clamp device and the gear. The relative positional relationship with the grindstone is regulated (the work used in this example is an output gear of an automatic transmission having a gear formed in an intermediate portion). Swing table
A pivot center pin 11a is embedded in the lower surface of 11, and the pivot center pin 11a is engaged with the slide table 12. Slide table 12 has pivot center pin 11
A swing table 11 is rotatably supported about a, and a servo motor 15 supported by a base (not shown) drives the base to move linearly in the longitudinal direction of the base (X-axis direction in the drawing) to position a workpiece. The swing table 11 is reciprocated in the X-axis direction during the correction processing while being positioned at the measurement position. A pulse generator (hereinafter referred to as PG) 16 for obtaining position data of the slide table 12 is coaxially coupled to the servo motor 15, and a servo amplifier 17 is provided to give a speed command to the servo motor 15 during positioning and correction processing. Is provided.

A connecting member 11b is fixed to the side of the swing table 11, and the connecting member 11b connects the swing table 11 and the crowning cam mechanism 13 to each other. Crowning cam mechanism
13 is crowning cam 18, worm 19, servo motor 2
0,21, PG22,23 and servo amplifier 24,25
A groove 18a passing through the crowning cam center is formed in the crowning cam 18, and the tip end of the connecting member 11b is slidably supported in the groove 18a (a roller (not shown) is attached to the tip end). Exist). Also crowning cam
A wheel 18b is formed on the outer peripheral portion of the wheel 18, and the wheel 18b meshes with the worm 19. A worm driving servomotor (manual rotation) 20 is coupled to the axis of the worm 19, and the worm is driven by the servomotor 20.
Wheel 18b rotates via 19 and crowning cam 18
The groove 18b forms a predetermined angle with respect to the moving direction of the slide table, that is, the X axis. The servo motor 20 is coaxially coupled with PG22 for obtaining the rotation angle data of the crowning cam 18 (crowning cam angle data).
A servo amplifier 24 is provided to give a speed command when setting the crowning cam angle. Further, in order to position the crowning center by linearly moving the base 26 on which the crowning cam 18, the worm 19, etc. are mounted, the servo motor (linear moving means) 21 supported by a base (not shown) and its A PG 23 is provided to obtain crowning center data, and a ball screw 2 that is coupled to the drive shaft of the servomotor 21 via a coupling 21a.
1b is screwed into a connecting member 27 connected to a base 26, and further, a servo amplifier 25 is provided to give a speed command to the servomotor 23 at the time of positioning the crowning center.
In this tooth flank shape correcting device, when the slide table 12 is in the original position, the pivot center of the swing table 11 and the work center coincide with each other, and the connecting member 11 of the swing table 11
b is located at the crowning cam center, and by driving the servomotors 20 and 21 from this state, the desired crowning amount and crowning center can be set.

Further, a work measuring device 30 is provided in order to measure the tooth surface shape of the work whose tooth surface is to be corrected. The work measuring device 30 includes a swing table 11 and a slide table 12 on the base.
Servo motor 31, PG3 installed so as not to interfere with
2. It comprises a servo amplifier 33, a linear gauge 34, and a tracing stylus 35. Ball screw 31 of servo motor 31
A bracket 31b for mounting the linear gauge 34 is screwed into a, and the bracket 31b moves in the X-axis direction when the servomotor 31 is driven by the speed command from the servo amplifier 33 when positioning the measurement position. While the contact point 35 is in contact with the tooth surface of the work 36 and moves over the entire range of the tooth width,
PG32 detects the position data in the tooth width direction and linear gauge 34
Detects position data in the tooth thickness direction. In this example, the work measuring device is installed in the tooth surface shape correcting device, but it can be installed outside the device, and its configuration is not limited to that of this example.

On the other hand, the control unit 10b of the tooth surface shape correction device 10 uses the PG substrate 40
˜42, positioning boards 43 to 45, multi-bus 46, central processing board 47 and storage device 48.
Detection data of PG22, 23 is input to the PG substrate 41, and detection data of the PG32 and the linear gauge 34 are input to the PG substrate 42, respectively. The multi-bus 46 is the above board 40 to 45,4
7 transmits and receives signals to and from the storage device 48, and the tooth surface shape measurement data (position data in the tooth width direction and the tooth thickness direction) of the work from the PG substrate 42 is stored via the multi-bus 46. Once stored in device 48. The central processing board 47 controls the crowning cam mechanism 13 and the work measuring device 30, and sends a speed command to the servo amplifier 33 via the positioning substrate 45 at the time of positioning the measurement position, and at the same time stores the work from the storage device 48. The toothed surface shape measurement data and the design data (reference value) are read to obtain the deviation of the workpiece from the crowning amount and the reference value of the crowning center, and the positioning board 41 is provided so that the tooth surface shape correction processing that eliminates the deviation can be performed. Servo amplifier through 24,2
Send a speed command to 5. Further, the central processing board 47 is from PG16 to P
The position data (processing position or measurement position) of the slide table 12 is determined by reading the position data of the slide table 12 input to the G board 40, and when the positioning state is changed, the servo amplifier 17 is operated via the positioning board 43. Speed command to. The control unit 10b may be incorporated in the tooth surface shape correcting device or may be separately installed.

Next, the structure of the mechanical portion 10a will be described in more detail with reference to the plan view of FIG. 3 (a) and the front view of FIG. 3 (b) (some devices are not shown in the drawing). Mechanical part 10a
In addition to the above-mentioned devices, the whetstone drive motor 51 that drives the whetstone 50, the whetstone turning motor 52 that turns the whetstone 50 around the Y axis to adjust the whetstone angle, and the whetstone 50 that is Y Grindstone moving mechanism 53 that linearly moves and positions in the axial direction, and hydraulic device
54, a cooling device 55, and a control device 56 for each of these devices, and a work clamp device 57 and a work rotation device 58 are provided on the swing table 11.

In the work clamp device 57, when the built-in cylinder 57a is operated, the tail center 57b moves on the X axis and the work 36
Clamps the work 36 together with the work rotating device 58 that penetrates the right end of the work 36 and supports the left end of the work 36. Transmitted to the work by the frictional force of the part). In this clamped state, the work rotating device 58 cooperates with a proximity switch (not shown) at the measurement position to index and rotate the teeth of the work at the measurement position, and at the machining position, rotationally drives the work (this rotation direction). Is the same as the rotation direction of the grindstone driving motor 51, for example). An electromagnetic clutch (not shown) used as a brake is connected to the work rotating device to obtain a desired servo control accuracy.

The swing table 11 is, as shown in FIG.
The pivot center pin 11a is engaged in the notch of the slide table 12, and the slide table 12
As it reciprocates, it rotates about this pivot center pin 11a. A member that contacts the lower surface of the slide table 12
A slide mechanism 60 that reciprocates the slide table 12 in the X-axis direction as the ball screw (not shown) of the servo motor 15 is driven is housed in the 59.
Has a function of positioning the slide table 12 at the measurement position or the processing position as described above.

Next, the operation of this tooth surface shape correcting device will be described in detail. At the time of measurement, first, the central processing board 47 is moved to the measurement position shown in FIG. 3B (where the work center and the swing table tenter / slide table center coincide in the X-axis direction at this position). From the positioning board 43 and the servo amplifier 17 to issue a speed command to the servo motor 15, drive the servo motor 15 until the slide table 12 reaches the measurement position, and after the positioning is stopped, do not swing the swing table 11 with a pin or the like not shown. The work is clamped by moving the work clamping device 57 to the right from the state shown in FIG. 3 (b) and inserting the left end of the work 36 into the work rotating device 58, and then operating the cylinder 57a. The tail center 57b by X
This is done by causing the workpiece 36 to pinch by penetrating the right end portion of the work 36 by making it go left on the axis, and at this time, the crowning cam mechanism 13 returns to the original position, and the tip end portion of the connecting member 11b of the swing table 11 is moved. Make sure that the swing table 11 is in parallel with the slide table 12 while matching the crowning cam center). Next, the entire work measuring device 30 is moved in the Y-axis direction to approach the work, and the contact point 35 is brought into contact with the tooth surface of the work. In this state, the central processing board 47 moves the positioning board 45 and the servo amplifier 33.
After that, the speed command is given to the servo motor 31, and the measurement is sequentially performed at each point of the tooth cross section of the work. This measurement is performed until the data for the tooth width of the tooth surface is obtained, and the obtained data, that is, the tooth width direction position data and the tooth thickness direction position data are
It is stored in the storage device 48 through the PG board 42 from the linear gauge 34 and the linear gauge 34. The work measuring device 30 used in this example is assumed to have a mechanism for tilting the entire measurement system so that the gear formed on the work can measure straight teeth or even helical teeth, and the work used in this example is Since it is a helical gear, the obtained measurement data is subjected to coordinate conversion and used for the following tooth surface shape correction.

On the other hand, at the time of processing, first, the slide table 12 is returned from the measurement position to the processing position shown in FIG. 3B and positioned, and then the following automatic crowning process is performed.
That is, first, the measured data and design data (reference value) of the work is read from the storage device 48, the two data are compared by the central processing board 47, and the crowning cam angle and the desired tooth surface shape are obtained based on the result. In order to set the crowning center (this set value is obtained by looking up the table data or calculating from the relational expression obtained in advance), the above-mentioned crowning cam angle is applied to the servo motor 20 via the positioning board 41 and the servo amplifier 24. And the positioning board 41,
A speed command for obtaining the crowning center is issued to the servo motor 21 via the servo amplifier 25.

After the above setting is completed, on the grindstone side, in order to move the grindstone 50 separated from the work in the Y-axis direction to contact the work, the grindstone moving mechanism 53 is operated to bring the work and the grindstone into a predetermined meshing state. However, since the work used in this example is a helical gear, the grindstone turning motor is operated before the movement so that the grindstone angle is adjusted to match the tilt angle of the helix. In this meshed state, the work rotating device 58 is driven to rotate the work 36 at a high speed (for example, 250 rpm), and the grindstone driving motor 51 is driven to drive a ring-shaped sprocket (not shown) with a silent chain to move the grindstone 50 to the work. By rotating the workpiece 36 in the same rotation direction, the portion of the workpiece 36 that contacts the grindstone 50 is ground.

Here, the relationship between the tooth surface shape obtained by polishing using the crowning cam mechanism and the set amount of the crowning cam mechanism can be generally expressed as follows. For example, as shown in FIG. 4 (a), when the work center and the slide table center C ₁ (which is also the pivot center of the swing table 11) are aligned with each other and the crowning cam is rotated by θ °, the slide table is rotated. 12 half of the total stroke h, i.e. h / 2 right while row for coupling the distal end portion of member 11b is moved from the crowning cam center C ₂ to C _3, while the crowning cam slide table 12 is h / 2 leftward The center is moved from C ₂ to C ₄ (the original position of the crowning cam center is shown on the Y axis in this figure for convenience of description). The swing amount L of the swing table 11 in the Y-axis direction during this period is shown in FIG. 4 (b) showing a cross section on the pitch circle in the meshing state of the helical gears and FIG. ), Where the pressure angle is α and the crowning amount is x, it can be expressed as L = x / sin α (1). Here, the crowning amount x is a general expression, where m is a distance from the swing table center to the tip of the connecting member 11b (m is a constant determined by device specifications), as shown in FIG. 4 (a). Therefore, if this equation is solved for θ, a desired crowning cam angle corresponding to the crowning amount can be obtained. The crowning amount x becomes x = 0.07025 mm when the stroke amount h = 30 mm, the pressure angle α = 20 °, and the crowning cam rotation angle θ = 30 °, for example.

By the way, the actual tooth flank shape of the workpiece is such that the crowning center (the position where the crowning shape has the maximum value) deviates from the tooth width center or the crowning amount x is larger than the desired crowning shape shown in FIG. 4 (c). Since it is different from the design data, when setting the crowning cam angle and crowning center as described above, it is necessary to set the movement amount of the crowning cam so as to eliminate the deviation between the above two data, so that the predetermined machining accuracy is achieved. A desired desired tooth surface shape can be obtained. (For example, if the crowning center is displaced from the tooth width center to the left by a, the slide table center is moved to the right by a to leave the uncut portion. Try to cut more on the more side).

If the workpiece after the tooth surface correction is measured by the workpiece measuring device 30, and the crowning cam angle is reset for each predetermined number of machining (for example, several hundreds) based on the obtained measurement data and design data, It is possible to correct the wear of the grindstone due to the work processing, and it is possible to automatically secure a desired processing accuracy even when the tooth surfaces of a large number of works are sequentially corrected.

(Effects of the Invention) As described above, the tooth surface shape correcting device of the present invention is configured to set the linear movement amount and the rotation amount of the crowning cam based on the comparison between the measurement data of the tooth surface of the gear and the design data. Since the relative positional relationship with the gear is adjusted, the amount of movement of the crowning cam is set appropriately according to the actual tooth surface shape so that the desired tooth surface shape that satisfies the specified machining accuracy can always be obtained. The surface shape correction device can be automatically adjusted, and troublesome manual adjustment and readjustment for each rod change can be eliminated. Further, by correcting the amount of wear of the grindstone in the setting of the amount of movement of the crowning cam, it is possible to ensure the desired processing accuracy even when the tooth surfaces of many gears are corrected.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a tooth surface shape correcting device of the present invention, FIG. 2 is a diagram showing the overall configuration of a first embodiment of the present invention, and FIGS. 3 (a) and 3 (b) are the same mechanism respectively. FIGS. 4A and 4B are plan views and front views showing the configuration of the parts, and FIGS. 4A, 4B, and 4C are views for explaining the tooth surface shape correction of the same example. 10 ... Tooth surface shape correcting device, 10a ... Mechanism part 10b ... Control part, 11 ... Swing table 12 ... Slide table, 13 ... Crowning cam mechanism 30 ... Work measuring device, 36 ... Work 50 ... Grindstone

Claims (1)

(57) [Claims] 1. A grindstone, a swing table which regulates a relative positional relationship between the grindstone and a gear, a crowning cam connected to the swing table, and a linear moving means for linearly moving the reclining cam, The rotating means for rotating the crowning cam, and the setting means for setting the amount of linear movement of the linear moving means and the amount of rotation of the rotating means based on a comparison between measurement data of the gear and design data. A tooth surface shape correcting device, characterized in that the tooth surface shape of a gear is corrected.