JPH0739044B2 - Clamp mechanism for non-lift revolving structure - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clamp mechanism suitable for a swinging body, for example, a member for placing a heavy object such as a turret tool rest of a machine tool and performing swivel indexing.

Conventional technology When the lathe becomes large, the turret tool post is also large and heavy tools are used to withstand heavy cutting, the turret becomes heavy, and the indexing speed cannot be increased. Also, in order to increase the speed, it is necessary to make the moving member as light as possible. Therefore, instead of lifting and unclamping the turret, the coupling attached to the back side of the turret and the coupling attached to the tool post body side are arranged concentrically, and the couplings that engage with both couplings are engaged. The non-lift type is adopted so that the turret will not be lifted after taking it off.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention Many of the couplings used are generally of the type referred to as a curvic gear. This coupling is also manufactured with high precision by improving the precision of machine tools, but it is still caused by uneven thickness of the coupling body, manufacturing error such as tooth thickness, tooth profile, parallelism of tooth surface, and distortion during meshing. It is difficult to mesh the three couplings uniformly and accurately. For this reason, there is a problem in that the clamping becomes uncertain and the accuracy of turret indexing and the processing accuracy are affected.

The present invention has been made in view of the above problems of the prior art, and it is an object of the present invention to provide a clamp mechanism capable of evenly engaging the meshing surface (hereinafter referred to as clutch surface) of the coupling.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a third coupling that can be simultaneously engaged and disengaged with a first coupling provided on the revolving structure side and a second coupling provided on the main body side. And a plurality of fan-shaped first adjusters provided on the back side of the first coupling in which a sensor member for detecting the clamp pressure and a displacement member for changing the thickness by external energy are combined. Then, the same number or almost the same number of second adjusters as the first adjuster are arranged on the back side of the second coupling, and the clamp of each part is obtained from the outputs of the sensor members of the first and second adjusters. A controller for displacing the displacement portion so as to detect the difference in force and compensating for the difference in clamping force at each portion based on this value is provided to uniformly adjust the meshing surface pressure of the coupling. .

When the turret is indexed, the third coupling is moved by the cylinder device and meshes with the first and second couplings. This meshing force is detected by the sensor member of each adjuster, and the control device is based on its output. A voltage for compensating the difference between the clamping forces is applied to the displacement member to change the thickness of the displacement member to make the clamping force uniform.

EXAMPLE An example will be described with reference to FIGS. 1 to 4. A swivel shaft 2 is rotatably supported by a bearing at the center of the tool rest body 1. A turret 3 for mounting a large number of tools is fixed to the upper end of the rotary shaft 2, and a gear 4 is fixed to the lower end. The gear 5 rotated by an indexing drive source (not shown)
The turret 3 is swiveled and indexed.

The tool rest main body 1 has an annular cylinder 6 centered around the turning shaft 2.
Is formed, and the donut-shaped piston 7 is fitted therein. At the center of the piston 7, a hollow piston rod 8 which is rotatable and axially movable relative to the swivel shaft 2 and which is itself prevented from rotating is integrally mounted.
A coupling 9 having a gear-shaped long clutch surface 9a radially cut is fixedly provided on the upper end of the piston rod 8, and is housed under the turret 3. The coupling 9 is provided with a turret side coupling 10 and a tool post main body side coupling 11 which are integrally meshed with each other. The coupling 10 on the turret side is radially machined on the upper surface of a disc fixed to the outer peripheral sleeve of the turret 3 so that the gear-shaped clutch surface 10a meshes with the outer peripheral side of the clutch surface 9a at approximately 1/2. Has been done. Similarly, the coupling 11 on the tool post main body side has a gear-shaped clutch surface 11a radially formed on the upper surface thereof in such a length that meshes with about 1/2 of the inner peripheral side of the clutch surface 9a. Coupling 9,
Needless to say, the gear-like clutch surfaces 9a, 10a, 11a of 10, 11 are formed with the same pitch and the same shape so as to be in close contact with each other.

Between the coupling 10 and the turret body 1 is the turret body 1
There are n fan-shaped (12-segment) adjusters 12 that are fixed on the center of the tool and are concentrically arranged. These adjusters 12 are proportional to the voltage when the tool rest body 1 side applies a DC voltage. A piezoelectric displacement element 12a extending in a vertical direction and a piezoelectric element 12b serving as a sensor that outputs a DC voltage in proportion to the pressure are formed in a pair on the upper surface coupling side thereof. The piezoelectric displacement element 12a and the piezoelectric element 12b may be upside down. And coupling 10
Since it is rotated together with the turret, a small gap is provided between it and the adjuster 12, and in order to eliminate this gap during clamping, a large number of piezoelectric displacement elements may be combined so as to obtain the necessary displacement. is there.

The same n or almost n similar adjusters 13 are also interposed between the coupling 11 and the tool rest body 1. Piezoelectric elements 12b and 13b used as sensors are those that output a voltage Sk = C ₁ · Esk when pressure · · Sk DC output voltage · · Esk constant · · C ₁ .

As the piezoelectric displacement elements 12a and 13a, those in which the displacement of Ak = C ₂ · V _A k is generated when the displacement is: · Ak DC applied voltage ·· V _A k constant ·· C ₂ are used.

Reference numeral 21 denotes the first control device which inputs the output of the piezoelectric element serving as a sensor and performs necessary calculations. 22 is the second control device and is the first
A voltage for displacing the piezoelectric displacement element is output based on the output of the control device. The first control device and the second control device can be formed uniformly.

In FIG. 5 showing the flowchart, it is assumed that the turret 3 of the tool rest is pivotally indexed and a command for a clamping operation for positioning is issued. Cylinder 6 of the turret body 1 in step S1
Unclamp side chamber 6b is connected to the discharge side
When pressure oil is sent to 6a, the piston 7 is lowered together with the piston rod 8. As the piston rod 8 descends, the coupling 9 is moved in the meshing direction so that the clutch surface 9a of the coupling 9 is fixed to the turret 3 and the clutch surface 10a of the coupling 10 and the clutch 11 of the coupling 11 fixed to the tool rest body 1. The meshing turret 3 is simultaneously clamped on the surface 11a.

The clamping pressure is transmitted to each adjuster 12, 13 of the segment. Each clutch surface has a pitch error, a shape error,
Parallel error Adjuster 12,13 for all segments due to mounting distortion, etc.
The uniform pressure does not act on it, and there is strength. Therefore, in step S2, first, the output voltage Esk at the piezoelectric element 12b of the sensor of each adjuster 12 is measured and input to the control device 21. In step S3, the controller 21 calculates the average output voltage _{^{Esk = ▲ Σ n k = 1}} ▼ Esk / n from the output voltage of each segment 12. In step S4, the controller 21 causes the output hydraulic pressure of each segment 12 to be excessive or insufficient ΔEs
Calculate k = Esk - Esk . Control device 2 in step S5
If 1 determines whether the variation in excess or deficiency of the output voltage is less than or equal to the set value ε%, and if NO, at step S6 the controller 22
Calculates the voltage ΔV _A k = ΔEsk × applied to the piezoelectric displacement elements 12a of each coordinator 12 corresponding to the basis of the calculated value DerutaEsk of excess or shortage from the control unit _{21 (C 1 / C 2)} . In step S7, the controller 22 causes each adjuster to
The applied voltage to the 12 piezoelectric displacement elements 12a is changed to a calculated value.
The pressure received by the piezoelectric element 12b of the sensor is changed by the expansion and contraction of the thickness of the piezoelectric displacement element due to the change of the applied voltage. After that, the procedure returns to step S2 and is confirmed in the same step. If YES in step S5, it is determined in step S8 whether the adjuster 13 has completed adjustment, and if NO, the process proceeds to step S2 and adjustment of the adjuster 13 is performed in the same manner. If YES, the processing starts after the clamp force adjustment is completed, and when the next turret indexing command is output, the clamp side chamber 6a of the cylinder 6 becomes the oil drain side and pressure oil is sent to the unclamp side chamber 6b, and the piston 7, The piston rod 8 rises and the clutch surface 9a of the coupling 9 comes off from the clutch surfaces 10a and 11a of the couplings 10 and 11, and the turret 3
Becomes an unclamp. The gear is rotated by a motor (not shown), and the turret is rotated and indexed by a predetermined angle by the gear 4 and the rotating shaft 8. Then, the above-mentioned clamping force adjusting operation is started by a clamping command.

Effects Since the present invention is configured as described above, it has the following effects.

The meshing force of the clutch surface at each part of the coupling of the turret and the coupling of the tool rest main body becomes uniform, and reliable clamping is possible, and the error caused by the nonuniformity of the meshing force can be completely eliminated.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional explanatory view of a part of the relevant part of the turret tool post, FIG. 2 is a layout view of the adjuster segmented, FIG. 3 is an explanatory cross-sectional view of the adjuster, and FIG. The control diagram and FIG. 5 are diagrams showing the adjustment procedure of the adjuster. 1 …… Turret body 2 …… Swivel axis 6 …… Cylinder, 7 …… Piston 8 …… Piston rod 9,10,11 …… Coupling 9a, 10a, 11a …… Clutch surface 12,13 …… Adjustment Element 12a, 13a ...... Piezoelectric displacement element 12b, 13b ...... Piezoelectric element of sensor

Claims (1)

[Claims] 1. A first coupling (10) provided on the revolving structure (3) side and a second coupling (11) provided on the main body (1) side.
In a clamp structure of a revolving structure, which comprises a third coupling (9) which can be engaged and disengaged with and at the same time, a sensor member (12) for detecting a clamp pressure on the back side of the first coupling (10).
A plurality of fan-shaped first adjusters (12) combining b) and a displacement member (12a) whose thickness is changed by external energy are provided, and the first coupling is also provided on the back side of the second coupling (11). The same number or almost the same number of second adjusters (13) as the adjusters (12) are arranged, and the first and second adjusters (12, 13) are arranged.
A controller for displacing the displacement member (12a, 13a) so as to detect the difference in the clamping force of each part from the output of the sensor member (12b, 13b) and compensate the difference in the clamping force of each part based on this value. (21, 22) are provided to uniformly adjust the meshing surface pressure of the coupling.