JPH10277825A - Internal machining center - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a floor space of equipment by mounting a spindle pinching a cutter for both flat seat and spherical seat machining uses, on a pair of slide units to be oppositely set up. SOLUTION: When a cutter is pinchedly held under pressure, a numerical control system commands and checks so as to make a cutter pinching part of a driving spindle S3 at the side of a work installing jig come to a machining standby position, while it releases the engagedness of an engaged pin regulating any slide motion of a sliding shaft of a cutter holder so as to make it not to freely shift in the axial direction of cutter rotation, emitting a rotative command to the driving side spindle S3. Next, if a NC driving slide unit 1 performs its retractable movements on the basis of a machining command of the numerical control system, a hydraulic driving slide unit 2 performs an integral motion with the NC driving slide unit 1 in a state that this slide unit 1 is pressed by a constant force.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inner surface cutting machine suitable for machining a flat seat and a spherical seat of a differential gear case.

[0002]

2. Description of the Related Art Conventionally, when a series of machining of a flat seat and a spherical seat of a differential gear case is performed, the flat seat machining and the spherical seat machining are performed by separate machines, and the workpiece is conveyed between these machines according to a production amount. It is often seen that a processing equipment having a transfer machine configuration is incorporated by incorporating a device or a posture changing device of a work.

[0003] In the case of a conventional internal cutting machine having a transfer machine configuration, in which the orientation of the work is changed using an index jig, the machining accuracy of the work is determined by the indexing accuracy of the index jig and the jig. Is greatly affected by the concentricity between the center of rotation and the center of attachment of the workpiece. For this reason, the method of inserting the cutter holder into the processing standby position in the work by moving the index jig that has positioned the work further up and down creates a factor that further reduces the machine accuracy. In this method, a cutter holder is inserted into a workpiece at a processing standby position. Therefore, a mechanism for inserting and removing the cutter holder into and from the work and a guide mechanism for allowing the cutter holder to move following the movement of the spindle are required at the upper part of the jig.

[0004] When the production volume is small, a single machine that specializes in only one process such as flat seat machining and spherical seat machining is adopted, and two single machines constitute a machining facility, and the work is stored in the machine. There is also adopted a method of inputting and dispensing into a warehouse by hand to reduce equipment costs. In this method, since a slide unit that moves oppositely on the rotation axis of the cutter is required for each processing step, there is a problem in terms of space occupied by equipment and production efficiency.

[0005]

The inner surface cutting machine of the transfer machine construction requires a large space occupied by the equipment, increases the equipment cost, and is not suitable for a work with a relatively small production volume.

An object of the present invention is to provide a low-cost and space-saving inner surface cutting machine capable of simplifying a machine configuration and easy to maintain and adjust, and capable of performing inner surface cutting with stable machining accuracy.

[0007]

Means for Solving the Problems A pair of slide units are disposed opposite to each other in the direction of the rotation axis of the cutter with the cutter interposed therebetween, and spindles provided at respective positions on the rotation axis of the plurality of cutters between the cutters are provided. The cutters placed on the slide unit arranged on the same side and arranged to be able to hold the cutters waiting at the respective processing standby positions are arranged so as to be able to be clamped, and by moving the slide unit oppositely, a plurality of cutters are simultaneously clamped and held by the respective spindles. The inner cutter can be formed by a desired cutter which is held by the clamping pressure by a spindle rotation command and a cutter rotation axis direction movement command.

When a plurality of drive spindles and driven spindles are mounted on a pair of slide units, a variation occurs between the centers of the drive spindle and the driven spindle. It is not possible to hold all the cutters simultaneously by simply controlling the movement. For this reason, the driven side spindle of the other paired spindle is set shorter in advance with respect to the pair of reference spindles, and a greater resilient force than the cutting thrust is applied to the driven side spindle end, so that a pair of short spindles between the two centers is provided. Is configured so that a resilient force equal to or greater than the cutting thrust acts on the sandwiched cutter.

[0009] In addition, by incorporating a posture conversion device for converting the posture of the work during the work transfer operation without using an index jig, the indexing accuracy of the index and the center of the jig turning center and the center of the work mounting can be adjusted. It is possible to realize an internal cutting machine with a configuration that is easy to maintain and that can easily maintain stable processing accuracy without being affected by the core degree.

[0010]

When a work is placed on a posture changing device which stands by at a work input port, the posture changing device changes the work putting posture by 90 ° and conveys the work to a position on the rotation axis of the spherical seat machining cutter. Next, the posture changing device raises the work to the height of the spindle suspended and held by the cutter holder at the processing standby position and the spindle which stands by at the rear on the rotation axis of the cutter. This raises the work to the cutter position suspended by the cutter holder at the machining height position,
The work is positioned on the jig by a locating pin of the jig for processing a spherical seat, and is fixed to the jig by a clamper. Next, when the NC driving slide unit, in which the moving position in the rotation axis direction of the cutter is controlled by the NC device of the slide unit on which the driving spindle is mounted, moves forward in the direction sandwiching the cutter, the driven spindle opposed to this is moved. The slide unit to be mounted also moves forward in the direction of pressing the NC drive slide unit by the hydraulic device, and the spindle can be inserted into a hole provided in the work to hold the cutter that stands by.

When the opposing slide unit moves to a position where the cutter held by the reference spindle is pressed and held by a predetermined force, the NC control device issues a command and confirms that the reference position of the spindle on the workpiece mounting side is the processing standby position. Then, a rotation command is issued to the drive-side spindle, and the inner surface of the work is cut in a state where the cutter is held with a constant force by the advance / retreat movement based on the processing command of the NC control device.

When the spherical seat machining is completed, the slide unit on which the spindle is mounted is retracted, the locating pin is removed from the work, the jig is unclamped, and the work is mounted on the raised posture changing device. When the posture converting device descends, the posture of the work is changed again by 90 °, and the work is conveyed to a work input port which is a position on the rotation axis of the cutter for processing a flat seat.

At this position, the posture changing device raises the work to the height of the spindle suspended and held on the cutter holder at the plane seat machining standby position and the spindle standing behind on the rotation axis of the cutter, and performs the same procedure as the spherical seat machining. After the flat seat processing is completed, the completed work is placed on the posture changing device, descends, and waits at the work input port.

The work which has completed the spherical seat and flat seat processing and waits at the work input port is paid out to the work payout port by the pusher of the payout device, and one cycle of the processing is completed.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a plan view of an inner surface cutting machine according to the present invention, and FIG. 3 is a side view thereof. FIG. 2 is an enlarged partial cross-sectional view of the spindle, showing a state in which a plurality of cutters are clamped and held between a driving spindle and a driven spindle at a processing standby position where the rotation axes of the cutters are parallel. FIG. 4 is a partial sectional view showing a mechanism for positioning and clamping a work on a jig and a slide mechanism for suspending and holding a cutter holder. FIG. 5 is a plan view showing one embodiment of a single machine for performing a flat seat machining by a conventional method.

Reference numeral 1 denotes an NC control slide unit for mounting the drive spindles S1 and S3, and reference numeral 2 denotes a hydraulically driven slide unit for mounting the driven spindles S2 and S4. The work W input into the work input port 3 is conveyed to the position 4 where the posture is changed by 90 ° by the posture changing actuator B and spherical machining is performed. Next, the lift actuator A of the posture changing device is raised, and the work is positioned and fixed by the locate pin 5 and the clamper C on the jig. As a result, the planned processing position in the work is positioned on the cutter holder H that suspends the spherical seat processing cutter 7 so as to be slidable in the rotation axis direction.

Next, when the NC-driven slide unit 1 and the hydraulic-driven slide unit 2 move forward to the central work side, the drive spindle and the driven spindle are inserted into holes formed in the work and stand by for spherical seating. The cutter 7 is held by the clamping pressure. In this case, the adjusting bolt 11 is adjusted so that the spindle S4 for spherical seat machining is 0.3 shorter than the calculated dimension in the cutter clamped state based on the dimensions of the spindles S1 and S2 for machining the flat seat in the state where the cutter is clamped.
Adjust the spindle length with. That is, in the state of the slide unit in which the flat seat cutter 6 is held between the flat seat processing spindles S1 and S2, the spherical seat processing spindles S3 and S2 are used.
At S4, if the user tries to clamp the spherical seat cutter 7 by 0.3,
And the elastic force of the elastic body 12 is used by the
Is transmitted to the adjustment bolt 11 through the shaft S3 so that the spherical seat processing cutter 7 is held by the spindles S3 and S4. At this time, the clearance δ1 between the front end of the spindle housing and the front end of the spindle shaft is configured to be larger than 0.3 so that the elastic force of the elastic body 12 is not dispersed to the spindle housing side. This elastic body 1
The resilience of 2 is set to 1.5 times the cutting thrust as a guide.

When the cutter 7 is clamped and held, the NC controller issues a command and confirms that the cutter clamping portion of the drive spindle S3 on the work mounting jig is at the machining standby position, and the cutter holder H is rotated by the cutter rotating shaft. The locking pin 13 that regulates the sliding of the slide shaft 9 of the cutter holder H is released so as not to move freely in the direction, and a rotation command is issued to the driving spindle S3. Next, when the NC-driven slide unit 1 moves forward and backward based on a processing command from the NC control device, the NC-driven slide unit 2 is pressed in a state where the NC-driven slide unit 2 is pressed with a constant force. Moves together with 1. That is, the cutter held by the pair of spindles while holding the pressure can cut the inner surface of the workpiece based on the rotation drive command of the spindle and the machining command of the NC control device.

When the machining is completed, the NC controller moves the NC-driven slide unit to the machining standby position and locks the sliding shaft 9 with the locking pin 13 for regulating the sliding of the cutter holder.

When the locating pin 5 on the jig is pulled out and the clamper C is released, the work is placed on the posture changing device which stands up by the actuator A, and the posture changing device descends and the posture is changed by 90 ° by the actuator B. To transport the work to the work input port at position 3.

Thereafter, the flat seat processing is performed in the same procedure as the above-mentioned spherical seat processing, and when the work having completed the flat seat processing comes to the work input port at position 3, the work discharging pusher device P removes the work from the work discharge port. Transfer to D and process 1
Complete the cycle.

The same effect can be obtained by adopting a method of absorbing a dimensional difference by using a fluid pressure instead of the elastic body 12.

[0023]

As described above in detail, according to the present invention, a spindle for holding a cutter for machining a flat seat and a cutter for machining a spherical seat is mounted on a pair of slide units which are arranged to face each other.
By moving the slide unit in opposition, a plurality of cutters can be simultaneously pressed and held by the respective spindles, so that the space occupied by the equipment can be reduced and a maintenance-adjustable machine configuration can be achieved. In addition, stable machining accuracy can be obtained by separating the attitude conversion device and the jig device, and by incorporating a work dispensing device for the purpose of labor saving, low cost equipment cost, high productivity and low production maintenance cost can be suppressed. It became an inner surface cutting machine that can do it.

[Brief description of the drawings]

FIG. 1 is a plan view of an inner surface cutting machine showing one embodiment of the present invention.

FIG. 2 is an enlarged partial cross-sectional view of a spindle in which a plurality of cutters are held by a driving spindle and a driven spindle at a processing standby position where the rotation axes of the cutters are parallel to each other;

FIG. 3 is a side view of the internal cutting machine showing one embodiment of the present invention.

FIG. 4 is a partial cross-sectional view showing a mechanism for positioning and clamping a work on a jig and a mechanism for suspending and holding a cutter holder according to an embodiment of the present invention.

FIG. 5 is a plan view showing one embodiment of a conventional single machine for performing flat seat machining.

[Explanation of symbols]

 Reference Signs List 1 NC drive unit 2 Hydraulic drive unit 3 Work input port 4 Spherical seat processing position 5 Locating pin 6 Flat seat processing cutter 7 Spherical seat processing cutter 8 Pad 9, 10 Sliding shaft 11 Adjust screw 12 Elastic body 13 Lock pin A Actuator B Swivel actuator C Clamper D Work payout port H Cutter holder P Pusher device S1-S4 Spindle W Work

Claims (2)

[Claims] 1. A cutter rotatably held by a cutter holder is held between a tip of a pair of spindles opposed to each other so as to be able to advance and retreat in a rotation axis direction of the cutter, and the cutter is rotationally driven. In the inner surface cutting machine that cuts the inner surface of the work by controlling the movement of the spindle in the rotation axis direction of the cutter,
A pair of slide units are arranged so as to be able to move in opposition in the direction of the cutter's rotation axis with the cutter held by the cutter holder at a position where the rotation axes of the plurality of cutters are parallel and waiting at the processing standby position. A drive side spindle and a driven side spindle are provided at each position sandwiching the cutter on the line, and each spindle is mounted on a slide unit arranged on the same side, and the slide unit is moved in the direction of the cutter rotation axis. The drive-side spindle and the driven-side spindle hold the cutters that stand by at their respective processing standby positions to hold the cutter, and perform the desired inner surface cutting by the rotational force of the drive-side spindle and the movement of the cutter in the rotation axis direction. Inner surface cutting machine. 2. A resilient force greater than a cutting thrust is applied to a driven spindle end of another pair of spindles based on an interval between the pair of spindles and the cutter holding portion to a cutter holding portion between the two centers. 2. The internal cutting machine according to claim 1, wherein a plurality of cutters are simultaneously held between a pair of spindles by a force equal to or greater than a cutting thrust as a configuration for compensating for the variation in the size by the amount of deflection of the elastic body.