JPS60118404A - Chuck for crankshaft - Google Patents

Abstract

PURPOSE:To cope with change of journal diameter, with no hand operated exchanging required, in addition to, as a matter of course, automatic exchanging in response to change of pin stroke. CONSTITUTION:In response to change of pin stroke of a crankshaft, the amount of eccentricity of a chuck body 3 with respect to a main shaft 1 is automatically changed by engaging with a driving coupling 11 of an automatic pin stroke changing device, rotatingly indexing a stopper 10, actuating a wedge member 9 for advance or retraction and moving a chuck supporting member 4 in the radial direction restricted within the stopper 10. Thus, no hand operation is required to exchange stages.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a crankshaft chuck for machining a crankshaft.

<Prior art> Conventionally, when machining crankshafts with different bin strokes, various techniques for automatically changing the amount of eccentricity of the chuck body with respect to the rotating main shaft in several stages are known, for example, from Utility Model Application No. 58-756.
Although this was developed in No. 63, etc., the diameters of the crankshaft journals supported by the journal holders provided in the chuck body had to be the same. Therefore, if the journal diameter is different, the setup must be changed manually by changing the journal holder.
As a result, it has been halved.

In conventional crankshaft chucks, there are technologies that automatically change the pin stroke as described above, but there are no systems that automatically change the setup when the journal diameter changes. The current situation is that this is not the case.

<Object of the Invention> The object of the invention is to provide a crankshaft chuck that can not only automatically change pin stroke changes but also respond to changes in journal diameter without requiring manual setup changes. l Provided.

<Structure of the Invention> The present invention provides a chuck main shaft that is movable and adjustable in the radial direction in order to adjust the amount of eccentricity according to the bin stroke of the crankshaft, and a journal portion of the crankshaft is held in the chuck body. For crankshafts with a configuration in which gripping claws are arranged eccentrically by a pin stroke with respect to the center of the main shaft and can be adjusted in forward and backward movement in the radial direction, and an indexing mechanism is provided to index the gripping claws with respect to the main shaft. It's Chuck.

<Example> Embodiment 7 of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, 1 is a main shaft, which is rotationally driven by a main shaft drive motor 2. In FIG. 3 is a chuck body provided on the main shaft 1 so as to be movable in the radial direction in order to adjust the amount of eccentricity according to the bin stroke of the crankshaft.

The mechanism for adjusting the radial movement of the chuck body 30 is as follows. As shown in FIG. 4, four radial guide surfaces 5 are provided on the end surface of the main shaft 1, and the chuck support member 4 connected to the chuck main body 3 by a gear coupling is connected to the guide member 6 provided thereon. The guide member 6 is slidably guided on the four guide surfaces 5 and is held down by a holding plate 7 fixed to the end face of the main shaft 1. The main shaft 1 is provided with a wedge member 9 that operates four chuck supporting members in a radial direction, and a cylinder 8 that moves the wedge member 9 forward and backward. A stopper 10 is provided to restrict the movement position of the radial direction in stages.

A coupling 11 is provided on this stopper 10, and the coupling 11 is moved forward and backward by a cylinder 13.
An automatic bin stroke switching device is provided which comprises a drive coupling 12 that engages and disengages from the bin and is rotationally indexed by a motor 14 in the engaged state.

The chuck body 3 has a journal portion J- of the crankshaft.
g The center point 02' of the chuck body 3 where the three gripping claws 16 held are eccentric by a pin stroke with respect to the spindle center 01
It is disposed so as to be movable in a radial direction centered at .

These three gripping claws 163- The movement mechanism in the radial direction is as follows.

The gripping claws 16 are guided and held by the chuck body 3 so as to be slidable in the radial direction about the center point 02 thereof. A one-tooth rack 17'lf is provided on the back surface of each gripping pawl 16 to slide in a direction perpendicular to the sliding direction of the gripping pawl 16, and meshes with a single tooth formed on the back surface of the gripping pawl 16. . An engagement pin 18 is protruded from the back surface of the one-tooth rack 17, and this engagement pin 18 is connected to a ring-shaped member 19 that is rotatably provided in the chuck body 3 concentrically with the center point 02. It engages with a radial engagement groove formed in the radial direction. A worm wheel 21 is provided on the ring-shaped member 19, and a worm n meshes with the worm wheel 21. This worm η is provided with a coupling part, which is moved forward and backward by a cylinder n to engage and disengage from this coupling part, and a main clamp nut runner consisting of a driving coupling 5 which is rotated by a motor in an engaged state is provided. ing.

Further, the chuck body 3 includes a turret-type rotational direction reference member that is supported by the center 15, supported by the work holder B, and abuts against the balance weight of the crankshaft held by the gripping claws 16 at the journal portion J-Y. 4, and a rotational direction reference suppressing member M that presses a balance weight against the rotational direction reference member 4.

The rotation direction reference member 4 is provided with a plurality of stepped reference surfaces, and has a coupling 31 as a means for indexing and rotating the rotation direction reference member 4, and a cylinder 32 is connected to the coupling 31.
An actuating device is provided which includes a drive coupling 31 that moves forward and backward to engage and disengage, and in the engaged state is indexed and rotated by a motor.

An indexing mechanism is provided for indexing the main shaft 1 (the gripping claws 16 provided on the chuck body 3) so as to correspond to the phases of the bins P of various crankshafts.The mechanism is as follows.The chuck The main body 3 is supported by the chuck support member 4 through a chuck main body support shaft 3a integrated with the chuck main body 3 so as to be movable in the axial direction, and in the retracted position of the chuck main body 3, the rotation direction is coupled by the engagement of the gear coupling. In the forward position, the gear coupling is disengaged and the chuck body 3 can be rotated.

This device for moving the chuck body 3 back and forth in the axial direction has a structure in which the chuck support member 4 is provided with a lift cylinder 36Y, and the piston within the lift cylinder 36 and the chuck body support shaft 3α are integrally constructed. Furthermore, gripping claw 1
The chuck body 30 indexing rotation device for indexing the 6-inch chuck is provided with a clutch 37 operated by a clutch engagement/disengagement cylinder at the rear end of the main shaft 1, and an indexing drive source 39 for rotating this clutch 377. A rotary joint 4C1 is provided between the clutch 37 and the chuck body support shaft 3α to absorb the radial movement of the chuck support member 4 and transmit the rotational Z to the chuck body 3. Reference numeral 41 denotes a center pressing cylinder that moves the center 15 forward and backward, and its piston rond and the center 15 are connected by a universal joint 42 at the rotary joint 400.

Next, the operation of the present invention will be explained. First, in order to change the eccentricity of the chuck body 3 with respect to the main shaft 1 due to a change in the pin stroke of the crankshaft, the drive coupling 12 of the automatic pin stroke switching device moves forward and engages the stopper 100 coupling 11. Rotation indexing 7 is performed, and the wedge member 9 moves forward and backward to move the chuck support member 47.
Automatic switching is achieved by moving in the radial direction regulated by the stopper 10.

Journal part JY of the crankshaft supported by the center 15
The holding claw 16 is operated by driving the drive coupling 5 of the main clamp nut runner forward and engaging the coupling of the worm n, and by rotating the worm 22 in forward and reverse directions, the ring-shaped member is moved through the worm wheel 21Y. 1
9 is rotated. This rotation of the ring-shaped member 190 causes the one-tooth rack 17' to move through the engagement pin 18Y that is engaged with the engagement groove. a- By sliding each gripping claw 1
It is designed to advance and retreat in the radial direction at the same time.

Therefore, when the diameter of the journal portion J changes, the gripping claw 1
It can be made to correspond arbitrarily by advancing and retreating in the radial direction of 6.

Furthermore, the gripping claws 16 must be made to correspond to the pin phase of the crankshaft (in order to index the main shaft 1, the three chuck bodies are moved forward by the lift cylinder 36, and the gear coupling is disengaged. This is achieved by operating the clutch engagement/disengagement cylinder 38F to engage the clutch 37'Y, and by operating the index drive source 39, the three chuck bodies are rotated to a required angle.

To position the crankshaft held by the chuck body 3 in the rotational direction, the rotational direction reference member 29 is indexed to correspond to various crankshafts. For this purpose, the drive coupling 31 of the actuating device moves forward and engages the coupling of the rotational direction reference member 4, and the rotational direction reference member 29 is rotated for indexing. One side of the balance weight of the crankshaft comes into contact with this rotational direction reference member 4, and the rotational direction reference suppressing member 34 presses and positions the rotational direction reference member 4 from the other side.

<Effects> As described above, according to the present invention, it is possible to automatically change the amount of eccentricity of the chuck body with respect to the main shaft as the bin stroke of the crankshaft changes, and also to adjust the eccentricity of the chuck body against changes in the journal diameter. The three gripping claws provided on the main body that can move forward and backward in the radial direction can automatically adjust to any desired position, and the gripping claws can also be rotated and indexed with respect to the main shaft to correspond to the pin phase. This process can be performed automatically, and has the advantage of fully automatic setup change when machining crankshafts with different bin strokes and journal diameters.

In addition, since the means for moving the gripping claws forward and backward is based on a one-tooth rank mechanism, the clamping force for the workpiece is obtained by a so-called wedge action, and the gripping action is strong enough to cope with heavy grinding and does not loosen. It has the effect of having

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the present invention, FIG. 2 is an enlarged sectional view of the main part,
Figure 3 is a partial partial view of Figure 2 viewed from arrow 1, Figure 4 is Figure 3 f.
FIG. 5, a cutaway view taken along line f-IV, is a sectional view showing the operating mechanism elements of the gripping claw. DESCRIPTION OF SYMBOLS 1-- Main shaft, 3... Chuck body, 4... Chuck support member, 9φ... Wedge member, 10-- Stopper, 161. - Gripping claw, 17--. 1-tooth rack, 18...engaging pin, 19...ring-shaped member, addition...engaging groove, n/fist/worm, sae...
Coupling, A...Gear coupling, I...Lift cylinder, 37...Clutch, 39.Fist/index drive source, B...Rotary joint.

Claims (1)

[Claims] The chuck body is mounted on the rotating main shaft so that it can be moved in the radial direction to adjust the amount of eccentricity according to the crankshaft pin stroke, and the three gripping claws that hold the journal part of the crankshaft on the chuck body are located at the center of the shaft. It is eccentric to the bin stroke and arranged so that it can be moved forward and backward in the radial direction.
A crankshaft chuck characterized by being provided with an indexing mechanism Z for indexing the gripping claws relative to the main shaft.