JPS6243703Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a chuck that indexably holds a workpiece, which is a crankshaft, having a plurality of crank pin portions having different phases.

Generally, a workpiece called a crankshaft has a journal part and a crank pin part, and a plurality of crank pin parts are formed, and the phase thereof differs depending on the number of cylinders of an engine. For example, for 2 cylinders and 4 cylinders, the phase angle is 2 phases (the phase angle between adjacent pin parts is 180 degrees), for 3 cylinders and 6 cylinders it is 3 phases (the phase angle is 120 degrees), and for 4 cylinders it is 4 phases (the phase angle is 90 degrees).゜), 5-phase for 5 cylinders (same
72°).

A crankshaft with such various phases,
In order to be able to perform phase indexing of multiple phases in order to process them with the same machine tool depending on the type, for example, as shown in Japanese Utility Model Application Publication No. 51-15794, multiple notches are provided in multiple index plates. A configuration has been proposed in which such a configuration is provided. For example, a two-phase index plate has two notches (the phase angle of adjacent notches is 180
The three-phase indexing plate has three notches (120°). But in reality,
It is extremely difficult to index every pin phase due to space constraints. Also,
Each index plate is provided with notches at equal pitches, and the pitch of the phase index cannot be changed.

On the other hand, table index time is one of the machining idle times in machining the crank pin part of a crankshaft, and since the pin parts of the same phase are continuously machined, taking a 6-cylinder crankshaft as an example, the After machining the first pin, the table was moved to the position where the sixth pin, which was the farthest away, was to be machined. For this reason, table indexing takes time, resulting in a decrease in efficiency. In the above case, if the adjacent second pin is machined after the first pin is machined, the table index amount can be minimized and the time can be significantly shortened, but conventionally, only equipitch phase indexing is possible. However, it was not possible to process each pin by changing the phase indexing pitch, and it was not possible to achieve time reduction.

In view of the above-mentioned conventional drawbacks, the present invention aims to enable pin phase indexing for any number of cylinders in order to enable machining of many types of crankshafts, and also to enable phase indexing for unequal pitches. purpose.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

Fig. 1 is a longitudinal cross-sectional view showing the whole of an embodiment of the present invention, and Fig. 2 is an enlarged cross-sectional view of the main part of Fig. 1, in which reference numeral 1 denotes a main shaft face plate around its axis O. It can be rotated freely. This face plate 1 has a chuck body 2.
is attached so as to be slidable in the radial direction along the guide portion 1a. At the center of the face plate 1 is a first
A rotating shaft 3 is mounted so as to be rotatable relative to the face plate 1. This rotary shaft 3 is a shaft that transmits the rotational force for performing phase indexing as described later. During indexing, the rotary shaft 3 is a shaft that transmits rotational force for performing phase indexing as described later. The rotational force is transmitted to the rotating shaft 5 of No. 2.

Since the second rotating shaft 5 has a spline portion 5a, it can rotate and move in the axial direction at the same time. This axial movement is performed by moving the locking pins 6, one upper and lower locking pin 6, in the axial direction by a shift fork 7, which are fitted into an annular groove 5c of a flange portion 5b formed at one end. The movement of the shift fork 7 is similar to that of the cylinder 7 shown in the first diagram.
This is done by sending hydraulic pressure to A.

The second rotating shaft 5 is keyed to the hollow shaft 8,
Piston member 9, holding members 10, 11, ball bearing 1
It is attached to the chuck body 2 via 2 and 13 so as to be rotatable relative to the chuck body 2. The piston member 9 is attached to the chuck body 2 via a holding member 10 so as to be able to rotate integrally with the chuck body 2, and cylinders 14 and 1 are provided at the front and central outer peripheral portions of the member 9, respectively.
5 is formed, and a gear coupling spring 16 is formed at the rear part.
is provided. The gear coupler 16 consists of a front part 16a and a rear part 16b, and in the illustrated state, both parts are in mesh with each other, but by sending hydraulic pressure to the cylinder 15, both parts 16
The engagement between a and 16b can be released.

A knock pin 1 is provided on the front end surface of the second rotating shaft 5.
7 is fixed in a protruding manner. This knock pin 17
is provided to engage with the reference hole when the workpiece W is attached as shown by the two-dot chain line.The reason for engaging with the reference hole in this way is that the workpiece (crankshaft) W In order to make the axis of the crank pin part Wp completely coincide with the axis O of the face plate 1 mentioned above, and to ensure that the workpiece W rotates correctly around the axis of the crank pin part Wp to be machined. be.

When attaching the workpiece W, first attach the journal holder 18 (various types are prepared depending on the type of workpiece) corresponding to the workpiece W to the chuck body 2, and then attach the journal of the workpiece W onto the chuck body 2. Department
Wj is installed, and then the clamp arm 19 is clamped to the journal part Wj to work on the workpiece W.
Firmly clamp and hold. The clamp arm 19 is pivotally supported by the chuck body 2 at a portion not shown, and in order to clamp the arm 19 to the journal portion Wj, hydraulic pressure is sent to a clamping cylinder 20 provided on the chuck body 2. Let's do it.

As shown in FIG. 2, a device for moving the chuck body 2 in the radial direction is provided on the outer periphery of the spindle face plate 1. That is, the first rotating shaft 3 described above
A socket hole 21a is bored at one end of the third rotating shaft 21 installed in a direction perpendicular to the axis of the
A first bevel gear 22 is fixed to the other end, and a second bevel gear 23 is always meshed with the bevel gear 22. Further, the second bevel gear 23 is fixed to a worm at a portion not shown, and the worm meshes with the worm gear 24. This worm gear 24 is fixed to a feed screw member 25 rotatably mounted on the face plate 1, and a male screw 25a is formed at the end of the member 25, and the male screw 25a is fixed to the chuck body 2. Natsuto 2
It is always screwed into the female screw number 6.

Therefore, the third
When the rotating shaft 21 is rotated around its axis, the rotational force is transferred from the first bevel gear 22 to the second bevel gear 23 to
The signal is transmitted in the order of worm gear 24 → feed screw member 25. Here, the feed screw member 25 does not move in the radial direction of the face plate 1. Therefore, the screwed nut 26 moves relatively in the direction of the arrow in FIG. 2, that is, in the radial direction of the face plate 1. As a result, the chuck body 2 moves in the same radial direction.

The reason why the chuck body 2 is configured to be able to move in the radial direction is that the eccentricity of the workpiece W (the distance from the axis of the journal part Wj to the axis of the crank pin part Wp) In other words, e) in FIG. 2 differs depending on the type of workpiece, and it is necessary to properly hold the journal portion and rotate it around the axis of the crank pin portion depending on the type of workpiece.

As shown in FIG. 1, the main shaft face plate 1 is fixed to the end of the main shaft 31 so that it can rotate integrally with the main shaft 31. The main shaft 31 is pivotally supported by a headstock 32, and a main shaft gear 33 is located approximately at the center of the main shaft 31. is fixed. A driving gear 35 is meshed with this main shaft gear 33 via an intermediate gear 34, and a shaft body 36 to which the gear 35 is fixed is connected to the synchronous shaft 3 via a coupling cylinder 37 at the end.
It is connected to 8. The reason why this synchronous shaft 38 is provided is that although the left part of the workpiece W is not shown in FIG. 1, it is actually the left journal part.
Since Wj is clamped in the same manner as shown in FIG. 1 and rotated around the axis of the crank pin part Wp by a shaft similar to the shaft 36, in such a case, both shafts are synchronized and rotated integrally. The synchronous shaft 38 is provided because it is necessary.

A gear 39 and a clutch 40 are provided at the rear end of the first rotating shaft 3, and the gear 39 is connected to the intermediate gear 4.
Encoder 4 meshes with another gear 42 via 1
3 is attached to the shaft body 44. In addition, the clutch 40 is driven by a servo motor 4 that can rotate in forward and reverse directions.
5, and even when the clutch 40 is in the disconnected state, the gear coupling 16 is in the engaged state when the workpiece W is being processed, so that the rotational force of the chuck body 2 is transferred to the holding member 10 and the piston member. 9, hollow shaft 8, transmitted to the first rotating shaft 3 via the second rotating shaft 5, and the shaft body 44 and the encoder 4
3 (however, in this case, the phase angle display function of the encoder 43 as described later does not work).

Incidentally, reference numeral 46 in FIG. 1 is a cylinder for clamping the chuck body 2 in the direction of the face plate 1.

Further, the nut runner device 50 in the upper part in FIG. 1 engages the lower end of its nut runner shaft 51 with the socket hole 21a described above, rotates the shaft 51 with the motor 52, and integrally connects the nut 26 and the chuck body 2. This is a device for moving in the radial direction. A displacement measurement device 53 installed adjacent to the nut runner device 50 is a device for measuring whether the chuck body 2 has moved by a predetermined amount in the radial direction.

In such a configuration, when machining the crank pin portion Wp of the crankshaft W, which is a workpiece, the journal portions Wj at both ends are clamped and held as shown in the figure, and the first The chuck body 2 and the crankshaft are rotated around the axis of the rotating shaft 3 to machine the pin portion Wp, but after machining one crank pin portion Wp, other crank pin portions with different phases are machined. Since Wp must be processed, it is necessary to determine the phase.

Regarding the effect of such phase indexing, the main shaft 31 is stopped rotating at the time of indexing, and the stopping position is always a constant position (this is done by a fixed position stopping device not shown). Further, the clamp arm 19 is released from the hydraulic clamp by the clamp cylinder 20. On the other hand, hydraulic pressure is sent to the cylinder 15 shown in FIG. 2 to disengage the gear coupling 16, that is, the second rotating shaft 5 is not restrained by the chuck body 2, and the servo motor 45 shown in FIG. The rotation of the gears 39 and 4 is appropriately transmitted to the first rotating shaft 3 by the clutch 40, and at the same time
1 and 42 to the encoder 43. Then, based on the display of the encoder 43, it is determined whether the crankshaft W has rotated by a predetermined phase angle.

In this way, for example, when the workpiece crankshaft is for a 6-cylinder engine as shown in Figure 3,
The first pin and the sixth pin are formed at the same phase position,
The second and fifth pins are in the same phase position, and the third
Since the pin and the fourth pin are formed at the same phase position, first, after machining the first pin, the servo motor 45 is rotated in the forward direction to rotate the crankshaft W in the direction of the arrow a', and the 240° phase is set. A different position of the second pin is determined and the second pin is machined (whether or not it has been accurately rotated by 240 degrees is determined by the display of the encoder 43 as described above). Next, the motor 45 is rotated in the same direction to index and process a third pin having a 240° phase difference. Since the fourth pin is in the same phase position as the third pin, it can be processed without phase indexing. The fifth pin is processed by rotating the motor 45 in the normal direction and indexing a position 120 degrees from the fourth pin position. The same applies to the sixth pin. In other words, this type of machining is done by rotating the servo motor in the same direction and indexing at unequal pitches, so that a→b→c...
This process sequentially processes adjacent pins.

Further, even with the same six-cylinder crankshaft, the crank pin portion can be machined by rotating the servo motor in the forward and reverse directions and indexing at unequal pitches as shown in FIG. That is, after machining the first pin, the servo motor 45 is reversed, the crankshaft W is rotated 120 degrees as indicated by the arrow a', the position of the second pin is indexed and machined, and then the third and fourth pins are machined. The servo motor rotates forward and the 5th and 6th pins are machined in sequence. This method also processes adjacent pins in order like a→b→c...

Even if the workpiece is a crankshaft other than one for a six-cylinder engine, the phase can be determined and processed in the same manner as described above. In this case, an encoder is used to accurately determine the phase angle of 120°, 240°, etc., but it can also be used for other 4-cylinder or 5-cylinder crankshafts. , if the gear coupling 16 with 120 gear teeth shifts by one tooth, the crankshaft will move 3
It is configured to rotate. In other words, any phase angle that is a multiple of the minimum index angle of 3 degrees can be freely determined, and the phase of the crankshaft of a 2, 3, 4, 5, 6, or 8 cylinder engine can be determined. Then, by adjusting the hydraulic pressure of the cylinder 15, the front part 16a and the rear part 16b of the gear coupling are disengaged and disengaged, and then the crankshaft W is rotated by a predetermined phase angle to perform phase indexing. I do. And again, cylinder 1
Engage the gear coupler spring by adjusting the hydraulic pressure in step 5. That is, in phase indexing, only the rear part 16b of the gear coupling meshes with the front part 16a of the gear coupling, offset by a number of teeth corresponding to a phase angle that is a multiple of 3[deg.].

As described above, the present invention includes a chuck body equipped with a journal holder which is attached to the end face of the main shaft so as to be slidable in the radial direction and eccentrically holds the journal portion of the crankshaft to be machined, and a chuck body which is pivotally supported by the chuck body and has the journal clamping means for press-clamping the journal part against the journal holder and releasing the pressing clamp of the journal part when the phase of the crankshaft is determined; a hollow shaft that is rotatable relative to the main body; and a hollow shaft that is allowed to move only in the axial direction and is coaxially attached to the hollow shaft, is rotatable integrally with the hollow shaft, and is removable from the end of the crankshaft; A rotation transmitting means for transmitting rotation to the crankshaft when the clamping means is unclamped, and a rotation transmitting means disposed between the hollow shaft and the chuck body to engage and disengage the former hollow shaft and the chuck body and release the meshing at the time of phase indexing. A gear coupling, a cylinder device for engaging and disengaging the gear coupling, a first rotating shaft connected to the rotation transmitting means via a universal joint and supported around the main shaft, and a first rotating shaft connected to the first rotating shaft via a clutch. Since the configuration consists of a servo motor connected to the servo motor that can freely rotate in forward and backward directions, and an encoder rotationally connected to the first rotating shaft, the minimum pitch of the phase index is the pitch of the teeth of the gear coupler, resulting in extremely fine indexing. The extension pitch can be adjusted, making it possible to determine the phase of the crankshaft for any number of cylinders. Also,
Since an indexing drive unit using a servo motor and an encoder is provided, it is possible to perform indexing with unequal pitches and in both forward and reverse directions, and it is possible to adopt the pin machining order that minimizes the table index amount. Idle time can be shortened.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing the entire embodiment of the present invention, FIG. 2 is an enlarged cross-sectional view of the main part of FIG. 1, FIG. 3 is an explanatory view showing the position of the crank pin of the crankshaft, 4 and 5 are explanatory diagrams showing the processing order of each crank pin portion. 2...chuck body, 3...first rotating shaft, 4...
...Universal joint, 5...Second rotating shaft, 8...Hollow shaft,
9... Piston member, 14, 15... Cylinder,
16...Gear coupling spring, 18...Journal holder, 19...Clamp arm, 25...Feed screw member, 26...Nut, 31...Main shaft, 40
...Clutch, 43...Encoder, 45...Servo motor, W...Workpiece (crankshaft).

Claims (1)

[Scope of utility model registration request] a chuck body equipped with a journal holder that is slidably attached to the end face of the main shaft in the radial direction and eccentrically holds the journal part of the crankshaft to be machined;
a clamp means which is pivotally supported by the chuck body and presses and clamps the journal part against the journal holder and releases the press clamp of the journal part when the phase of the crankshaft is determined; a hollow shaft which is supported by the chuck body and is rotatable relative to the chuck body; and a crankshaft which is coaxially mounted to the hollow shaft and is allowed to move only in the axial direction and is rotatable integrally with the hollow shaft. rotation transmitting means that is removable from the end of the chuck and transmits rotation to the crankshaft when the clamp means is unclamped; A gear coupling that releases meshing during phase indexing, a cylinder device for engaging and disengaging the gear coupling, and a first rotation shaft that is connected to the rotation transmission means via a universal joint and supported around the main shaft; 1. A chuck for holding a crankshaft, comprising: a servo motor capable of forward and reverse rotation connected to the first rotation shaft via a clutch; and an encoder rotationally connected to the first rotation shaft.