JPS5837530Y2 - Crankshaft processing equipment - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a device for machining an eccentric portion of a crankshaft, and particularly relates to a crankshaft machining device with improved machining accuracy.

Conventionally, as a crankshaft machining device, both ends of the crankshaft are gripped by a pair of left and right main shafts, and while the crankshaft is rotated, an annular machining tool into which the crankshaft is inserted is rotated, and at a right angle to the axis of the crankshaft. A known tool is known in which the outer circumferential surface of an eccentric portion of a crankshaft is machined using a cutting edge provided on the inner circumferential surface of the processing tool by moving the crankshaft in the direction of the crankshaft.

However, in the conventional crankshaft machining apparatus of this type, a tool unit supporting a machining tool is guided and supported on a tool holder so that the upper and lower parts of the tool can reciprocate in a direction perpendicular to the axis of the crankshaft.

For this reason, when heat from cutting the crankshaft is transferred to the tool unit, the tool unit is thermally displaced upward with respect to its lower guide portion, changing the cutting position of the machining tool relative to the crankshaft, and machining There was a drawback that accuracy decreased.

This idea is an attempt to eliminate the above-mentioned conventional drawbacks. By supporting the tool unit on the tool support stand at the horizontal line passing through the center of the machining tool, even when the tool unit is heated, the tool unit will not move up or down. It is an object of the present invention to provide a rank-axis machining device as described above in which the machining accuracy is not reduced.

An embodiment of this invention will be described below with reference to the drawings.

In FIGS. 1 and 2, 1 is a bed. A pair of left and right headstocks 2 are provided on the bed 1, and a spindle 3 supported by the headstocks 2 is synchronized by the drive of a pulse motor 4. Axis 5. Worm 6, worm wheel 7, interlocking shaft 8° fixed to worm wheel 7, worm 9 provided on interlocking shaft 8. Driving force is transmitted through a path of a worm wheel 10 provided on the main shaft 3, and the worm wheels are driven synchronously.

Chucks 12 that removably grip both ends of the crankshaft 11 are provided at opposing inner ends of the left and right main shafts 3, respectively.

Further, left and right tool support stands 13 are supported on the bed 1 so as to be able to reciprocate in the left-right direction.

These support stands 13 have a left-right symmetrical structure, and the feed motor 14
The support stand is reciprocated in the left-right direction by the drive of the support stand feed screw 15.

A gear box 18 is fixed to one side of the support base 13, and a tool unit 1, which will be described later, is attached to the gear box 18.
A pulse motor 17 is fixed so as to be located below the guide protrusion 29 of No.6.

The rotation of the pulse motor 17 is transmitted to the feed screw 21 via gears 31, 19, 20 in the gear box 18.

This feed dog 21 is screwed into the tool unit 16, and is configured to reciprocate the tool unit 16 in a direction perpendicular to the reciprocating direction of the support base 13.

The tool unit 16 has a tool holding cylinder 22 and a bearing 23.
An annular cutting tool 24 is removably fitted into the holding cylinder 22, and the processing tool 2
4 has a cutting edge 25 formed along its inner peripheral surface.

The tool unit 16 is provided with a drive motor 26,
A drive gear 27 provided on the outer periphery of the holding cylinder 22 is driven by a drive motor 26 via a drive force transmission mechanism (not shown).
The rotational force is transmitted to the machining tool 24 via the holding cylinder 22.
It is designed to be rotated.

A guide protrusion 2 is provided on the back side of the tool unit 16.
8 is formed protrudingly, and the guide protrusion 28 is located on a horizontal line passing through the center of the processing tool 24 and is guided and supported by a support portion 29 formed on the support base 13 so as to be able to reciprocate in a direction perpendicular to the axis of the processing tool 24. ing.

Note that 30 in FIG. 1 is a nut provided on the support base 13 and into which the feed screw 15 is screwed.

Next, the operation of the crankshaft machining device configured as above will be explained.

First, with the tool support 13 retracted so that the tool unit 16 is located outside the chuck 12 provided on the main shaft 3 in the left-right direction in FIG. is supported between the left and right main shafts 3.

The support stand 13 is advanced by the drive of the feed motor 14, and the eccentric portion 11a of the crankshaft 11 is moved toward the processing tool 2.
It is fitted into the processing tool 24 at a position corresponding to the cutting edge 25 of No. 4.

In this state, the left and right main shafts 3 are driven by the pulse motor 4.
, while the chuck 12 is rotated synchronously to rotate the crankshaft 11 around its axis, the processing tool 24 is rotated in the opposite direction to the crankshaft 11 via the holding cylinder 22 by driving of the drive motor 26, and the pulse motor 17 is rotated. The processing tool 24 is moved by driving the tool unit 16 in a direction perpendicular to the axis of the crankshaft 11 by sliding the guide protrusion 28 against the support part 29 of the support base 13. 25, the outer peripheral surface of the eccentric portion 11a of the crankshaft 11 is cut.

After finishing machining one eccentric portion 11 a, the pulse motors 4 and 17 and the drive motor 26 are stopped, and the feed motor 1
4 is driven to move the support stand 13, the cutting edge 25 of the processing tool 24 is brought into correspondence with the eccentric portion of the crankshaft 11 to be machined next, and the same cutting process as described above is performed.

By repeating the above operations, the eccentric portion 11a of the crankshaft 11
After all the machining is completed, the support stand 13 is moved back from the chuck 12 to the left and right outwards in FIG. 1, and the crankshaft 11 is removed from the chuck 12.

Note that the above explanation was given for one side of the tool support 13, but in this embodiment, the left and right tool support 13 can be used simultaneously to perform simultaneous machining on two eccentric portions 11a. Although this is possible and improves processing efficiency, it is also possible to provide only one support stand.

As explained above, the crankshaft machining device according to this invention uses guide protrusions formed on both sides of the tool unit to support the tool so that it can reciprocate in a direction perpendicular to the axis of the tool at a horizontal line passing through the center of the tool. Because it is configured to be guided and supported by the table, when heat during machining is transferred to the tool unit, the tool unit will only thermally displace up and down with respect to its guide support position, that is, the center of the machining tool, and the machining tool will not move against the crankshaft. There is no change in the cutting position, which has the advantage of preventing a decrease in machining accuracy.

In addition, since the device of the present invention has a configuration in which the feed motor that reciprocates the tool unit via the feed mechanism is placed below the guide protrusion, the tool support base that guides the guide protrusion of the tool unit is placed slightly at the front and rear of the bed. This has the advantage that by simply protruding in this direction, further overhang of the motor in the front-rear direction of the bed can be suppressed, and an imbalance in the center of gravity can be prevented.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway side view showing an embodiment of this invention, and FIG. 2 is a sectional view taken along line II--II in FIG. 1. 3...Main shaft, 11...Crankshaft, 1
1 a... Eccentric part, 13... Tool support stand, 16... Tool unit, 24...
Processing tool, 25... Cutting blade, 28... Guide protrusion, 29... Support part.

Claims (1)

[Scope of utility model registration request] A main shaft that removably grips the end of the crankshaft and rotates the crankshaft, a tool support that can reciprocate along the axial direction of the crankshaft, and a tool support that is supported by the support and is perpendicular to the axis of the crankshaft. A tool unit that is reciprocated in the direction of In a tool that processes a crankshaft with a cutting edge provided on the peripheral surface, the guide protrusion formed on both sides of the tool unit can be reciprocated in a direction perpendicular to the axis of the tool at a horizontal line passing through the center of the tool. A crankshaft machining device characterized in that a feed motor is disposed below the guide protrusion to guide and support the tool unit on a support base and to reciprocate the tool unit via a feed mechanism.