JPS6157136B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a steady rest device for steadying an unprocessed journal portion on a crankshaft.

In conventional crankshaft machining equipment that sequentially cuts a plurality of journal parts arranged at regular intervals on the crankshaft from one end of the crankshaft to the other end in accordance with the arrangement order, the machining tool The machined journal part adjacent to the journal part machined by the machine tool is rotatably supported by the steady rest device. Since the journal on the opposite side has not yet been processed and is in a so-called black-skinned state, it is difficult to rest the shaft of the unprocessed journal to prevent it from shifting. The machine is designed to be machined only by the steady rest action.

However, in machines where the crankshaft is machined with such one-sided support, the support rigidity of the crankshaft steady rest is insufficient, and especially in heavy cutting, the crankshaft is deflected and machining accuracy deteriorates. This caused the problem that highly efficient machining could not be performed.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a steady rest device that can grip an unprocessed journal part reliably without causing the axis of the unprocessed journal part to deviate.

Embodiments of the present invention will be described below based on the drawings.

In FIG. 1, numeral 10 indicates a bed, and a pair of left and right headstocks 11 and 12 are installed on this bed 10 with a predetermined interval between them.
A main shaft 13 (see FIG. 6) is rotatably supported on the same axis as the main shaft 12, and is driven to rotate synchronously by servo motors 15 and 16.
Chucks 17 and 18 for gripping both ends of the crankshaft W are provided at each tip of the main shaft 13, and these chucks 17 and 18 are connected to chuck operating cylinders 19 and 20 installed at the rear of the headstocks 11 and 12. It is designed to be opened and closed.

Also, on the bed 10, there is a pair of left and right indexing tables 2.
1 and 22 are supported slidably in a direction parallel to the spindle axis, and indexed and moved by servo motors 23 and 24. Tool units 25 and 26 are mounted on the indexing tables 21 and 22 so as to be slidable in a horizontal direction perpendicular to the spindle axis, and the feed of these tool units 25 and 26 is controlled by a servo motor (not shown). There is. tool unit 25,
Tool holders 27 and 28 are rotatably supported on the tool holder 26 around an axis parallel to the spindle axis, and a gear 29 is formed on the outer periphery of the tool holders 27 and 28.
An unillustrated rotary drive device is connected to (FIG. 2). The tool holders 27 and 28 are also fitted with annular cutting tools 30 (FIG. 2) having cutting edges formed on their inner peripheral surfaces, and the inner diameters of these processing tools 30 are set to be larger than the maximum runout of the crankshaft W. has been done.

In FIGS. 2 and 3, the indexing table 21
At the top, there is a first
A support stand 31 is installed. A sleeve member 32 is supported on the support base 31 so as to be rotatable around an axis parallel to the main shaft axis.
A shaft member 33 is fitted into the shaft member 33 so as to be relatively rotatable therein.
A pair of steady rest arms 34 and 35 are fixed to the tips of the sleeve member 32 and the shaft member 33, and are overlapped so as to be openable and closable.
Gripping rollers 36 and 37 are rotatably supported on the inner surfaces of 4 and 35, respectively. The pair of steady rest arms 34 and 35 are separated from the processing tool 30 by a certain distance in the direction of the spindle axis, and are mounted on the processing tool 3 on the crankshaft W.
The machined journal part adjacent to the journal part to be machined at 0 is rotatably supported via gripping rollers 36 and 37.

A screw shaft 39 rotatably driven by a rotary motor 38 is rotatably supported on the first support base 31, and a feed nut 40 is screwed onto the screw shaft 39.
A rack tube 41 having a fixedly attached rack is fitted so as to be able to move only in one direction. An axially long spur gear 42 rotatably supported by the support base 31 is engaged with an unillustrated rack formed on the rack cylinder 41. A pair of parallel operating shafts 43 and 44 are also slidably supported on the first support base 31, sandwiching the spur gear 42 therebetween. A pair of operating shafts 43, 44
A rack 45, 46 is formed on each inner surface of the gear 42, and these racks 45, 46 are engaged with both sides of the spur gear 42. Engaging portions 47 and 48 are also formed on the pair of operating shafts 43 and 44, and these engaging portions 47 and 4
8 are engaged with operating levers 49 and 50 connected to respective rear portions of the sleeve member 32 and shaft member 33.

Therefore, when the screw shaft 39 is rotationally driven by the rotary motor 38, the rack cylinder 41 is slid and the spur gear 42 is rotated, thereby causing the pair of operating shafts 43,
44 are slid in opposite directions, and the pair of steady rest arms 34 and 35 are opened or closed via the sleeve member 32 and shaft member 33.

Thus, the above-described configuration constitutes a first steady rest device 51 that rotatably supports a processed journal portion adjacent to a journal portion processed by the processing tool 30, and this first steady rest device 51
The pair of steady rest arms 34 and 35 can be opened to an angle that does not interfere with the crankshaft W.

2, 4, 5 and 6, a second support 53 is installed on the indexing table 21 in front of the tool unit 25. As shown in FIGS. An annular rotating body 54 is mounted on the support base 53 and supports the main shaft 13.
This rotating body 54 is rotatably supported concentrically with the
A gear 55 is formed on the outer periphery of. Support stand 53
One end of a synchronizing spline shaft 57 to which a gear 56 meshing with a gear 55 is attached is rotatably supported, and this spline shaft 57 is rotated in the axial direction by a spline sleeve 59 rotatably supported by a gear box 58 fixed to the headstock 11. They are fitted so that they can only be moved.
A gear 60 is formed on the spline sleeve 59, and this gear 60 is connected to a drive gear 62 mounted on the main shaft 13 via a required gear transmission mechanism 61 housed in a gearbox 58, thereby causing the rotation. The body 54 is configured to be rotated synchronously with the main shaft 13 at a ratio of 1:1.

As shown in FIGS. 4 and 5, a plurality of support shafts 65 are rotatably supported in parallel to each other at equally divided positions on the circumference of the rotating body 54, and a drive arm 66 is locked to these support shafts 65. There is. Each support shaft 65 is also rotatably fitted with a plurality of gripping arms 67 for gripping the journal portion of the crankshaft W, and these gripping arms 67 are linked to each of the drive arms 66 so as to be relatively rotatable by a minute angle. There is. A spring 68 is interposed between each of the gripping arm 67 and the drive arm 66, and the force of the spring 68 normally urges the gripping arm 67 inwardly (in the gripping direction) with respect to the drive arm 66. . The plurality of gripping arms 67 are separated from the processing tool 30 by a certain distance in the direction of the spindle axis, and are configured to grip an unprocessed journal portion adjacent to the journal portion to be processed by the processing tool 30 on the crankshaft W. ing.

A plurality of pivot shafts 69 are also rotatably supported on the rotary body 54 at equally divided positions on the circumference in parallel with the support shafts 65, and an engagement link 70 and an operating link 71 are respectively latched onto these pivot shafts 69. There is. The operating link 71 is engaged with wedge members 72 for backing up the gripping arm, which are slidably fitted on the rotating body 54 , and these wedge members 72 are moved forward by engaging the gripping arm 67 by the force of a spring 73 . biased in the direction.

A rotary ring 75 is disposed on the inner periphery of the rotary body 54, and a plurality of support rollers 7 on the circumference are pivotally supported by the rotary body 54.
6, and this rotation ring 7
A plurality of engagement holes 77 and engagement pins 78 are provided at equally divided positions on the circumference of 5, respectively. An operating link 79 that is engaged with the support shaft 65 is loosely engaged with the engagement hole 77, and an engagement link 70 that is engaged with the pivot shaft 69 is engaged with the engagement pin 78. There is. An actuating pin 81 is protruded from the front surface of the rotating ring 75, and a pair of actuating cylinders (not shown) installed on the support stand 53 facing each other with the actuating pin 81 sandwiched in between actuate the actuating pin 81 in a tangential direction of the rotating ring 75. When pushed by a certain amount, the rotary ring 75 is rotated by a predetermined angle clockwise and counterclockwise in FIG. 4.

Therefore, when the gripping arm 67 is to be released from the gripping state shown in FIGS. The engagement link 70 is rotated, and this engagement link 70
The wedge member 72 is retracted by the actuating link 71 coaxially with the gripping arm 67 against the force of the spring 73 to a position that allows the gripping arm 67 to rotate. Subsequently, the operating link 79 is rotated by the end face of the engagement hole 77, and the drive arm 66 and the gripping arm 67 are rotated in a direction away from the journal portion. However, when the pressing force on the operating pin 81 by the operating cylinder is released, the wedge member 72 rides on the outer peripheral surface of the gripping arm 67 in the released state due to the force of the spring 73 and stops.

When the journal portion is to be gripped by the grip arm 67, the rotation ring 75 is rotated counterclockwise by the other operating cylinder, and the grip arm 67 is rotated together with the drive arm 66 to grip the journal portion. In this state, the wedge member 72 engages with the rear part of the grip arm 67 due to the force of the spring 73 and the force of the grip arm 73, and is backed up. At this time, the gripping arm 67 and the driving arm 66
Since they can rotate relative to each other, even if the journal part is in an unprocessed black crust state, the plurality of gripping arms 67 on the circumference can be attached to the spring 68 on the outer periphery of the journal part.
They sequentially come into contact with each other due to the force exerted by them, and are backed up by the wedge member 72 at that position, so that the unprocessed journal part in a black scale state is firmly clamped without being displaced in the radial direction.

Thus, the above-described configuration constitutes a rotatable second steady rest device 83 that grips an unprocessed journal portion adjacent to a journal portion processed by the processing tool 30, and this second steady rest device 83
The plurality of gripping arms 67 can be opened to an angle that does not interfere with the crankshaft W.

Next, the operation of the apparatus of the present invention constructed as described above will be explained with reference to FIG.

In the original position shown in FIG.
Clamp with 9 and 20. Subsequently, the indexing table 21 is slid by a predetermined amount by the servo motor 23, and the processing tool 30 is positioned at a position corresponding to the first journal portion J1 of the crankshaft W. In this state, when the rotating ring 75 is rotated counterclockwise in FIG. 4 by one of the operating cylinders (not shown), the operating ring 7
9. The support shaft 65 and the drive arm 66 are rotated, and thereby the plurality of gripping arms 67 are rotated integrally via the spring 68. When the gripping arm 67 comes into contact with the outer periphery of the second journal part J2 in a black flake condition and stops, the drive arm 66 is further rotated while compressing the spring 68, thereby removing the black flake condition with an uneven machining amount. The second journal portion J2 is gripped by a plurality of gripping arms 67 with the force of a spring 68, respectively. Second journal section
Each gripping arm 67 that gripped J2 has a spring 73
It is backed up by the wedge member 72 urged by force and is prevented from retreating.

The first journal part to be processed in this way
The unprocessed second journal portion J2 adjacent to J1 is gripped by the plurality of gripping arms 67 of the second steady rest device 83. In this case, the first steady rest device 51
The pair of steady rest arms 34 and 35 are open as shown in FIG. 7A.

In this state, both main shafts 13 are driven to rotate synchronously by servo motors 15 and 16, and both chucks 1
A crankshaft W supported by 7 and 18 is driven to rotate around the journal portion. The rotation of the main shaft 13 is transmitted from the drive gear 62 to the rotating body 54 via the gear transmission mechanism 61, the spline sleeve 59, the synchronizing spline shaft 57, and the gears 56, 55, The steady rest device 83 is rotated integrally with the crankshaft W. At the same time, the tool holder 27 on which the machining tool 30 is mounted is rotated in the opposite direction to the crankshaft W by a rotation drive device (not shown), and the tool unit 25 is rotated at right angles to the axis of the crankshaft W by a servo motor (not shown). direction, and the processing tool 30 moves the first
Cut the outer peripheral surface of the journal part J1.

When the predetermined machining of the first journal portion J1 is completed, the tool unit 25 is retreated to its original position, the rotation of the tool holder 27 is stopped, and the rotation of the main shaft 13 is stopped at a certain angular position. Subsequently, when the first actuating cylinder is retreated and at the same time a second actuating cylinder (not shown) opposite thereto is actuated to rotate the rotary ring 75 clockwise in FIG. The engagement link 70 is rotated, and the wedge member 72 is moved back against the force of the spring 73 by the operating link 71 coaxial with the engagement link 70 and separated from the gripping arm 67 . Thereafter, the drive arm 66 and the gripping arm 67 are rotated via the operating link 79 that engages with the end surface of the engagement hole 77 of the rotation ring 75 to release the grip on the second journal portion J2. In this state, the indexing table 21 is slid by the distance between the pitches of the journal portion by the servo motor 23, and the processing tool 30 is positioned at a position corresponding to the second journal portion J2. As a result, the second steady rest device 83 corresponds to the third journal portion J3 which is in a blackened state adjacent to the second journal portion J2, and the first steady rest device 51 corresponds to the processed first journal portion J3. Department
Compatible with J1.

When the indexing table 21 is slid a certain amount, the rotation ring 76 is rotated counterclockwise by the first actuating cylinder in the same manner as described above, and the third journal portion J3 is rotated by the plurality of gripping arms 67. It is grasped and backed up by the wedge member 72. At the same time, the screw shaft 39 is rotationally driven by the rotary motor 38, and the rack cylinder 41, the spur gear 42 and the operating shaft 4 are rotated.
Sleeve material 32 and shaft member 3 via 3 and 44
3 are rotated in opposite directions. As a result, the pair of steady rest arms 34 and 35 are closed,
Gripping roller 3 holds the processed first journal part J1.
6, 37 so as to be rotatable on the axis of the main shaft.

After that, in the same manner as described above, the servo motor 1 is
5 and 16, the main shaft 13 is rotationally driven synchronously, and the rotating body 54 equipped with the second steady rest device 83 is synchronously rotated via the synchronization spline shaft 57, and the crankshaft W is rotationally driven. be done.
At the same time, the tool holder 27 on which the machining tool 30 is attached is driven to rotate, and the tool unit 25 is advanced, and the machining tool 30 moves the second journal part.
Cut the outer peripheral surface of J2. When processing the second journal part J2, the second journal part J2 is
The journal parts J1 and J3 on both sides adjacent to J2 are supported by the first and second steady rest devices 51 and 83.

Thereafter, the third, fourth, fifth, sixth, and seventh journal parts J3, J4, J5, J6, and J7 are sequentially cut in accordance with the arrangement order of the journal parts on the crankshaft W. And the 3rd to 6th journal section J3
~ When processing J6, the second journal part J2
In the same manner as in the machining process, the adjacent journal parts on both sides are supported by the first and second steady rest devices 51 and 83 (see FIG. 7B), and the final seventh journal part J7 is machined. In this case, the sixth journal portion J6 is supported by the first steady rest device 51, and the second steady rest device 83 is released, as shown in FIG. 1st
It is supported at two points by the steady rest device 51 and the chuck 18.

As described above, the present invention includes a rotary body that is rotatably supported around the spindle axis, which is rotated synchronously with the spindle, on an indexing table that is movable in the axial direction of the crankshaft. The structure is such that a plurality of gripping arms, each of which grips a journal part with a spring force, are rotatably provided, and these gripping arms are backed up by a back-up member to prevent them from retreating. As a result, it becomes possible to accurately and reliably grip the unprocessed journal part, which is in a black-skinned state, without shifting its axis, and it becomes possible to appropriately prevent vibration of the crankshaft during processing. .

Therefore, in addition to the steady rest device having the above configuration,
If a known steady rest device for rotationally supporting the processed journal part is provided, it is possible to support the processed journal part and the unprocessed journal part in two places adjacent to the journal part to be processed. Therefore, heavy cutting can be performed.

[Brief explanation of the drawing]

All drawings show embodiments of the present invention.
Figure 1 is a front view of the crankshaft machining device, Figure 2 is an enlarged sectional view of the main parts showing the operating state of Figure 1, and Figure 3 is a front view of the crankshaft machining device.
Figures 4 and 5 are - lines in Figure 2,
FIG. 6 is a cross-sectional view showing a synchronization device between the main shaft and steady rest device, and FIG. 7 is an explanatory view showing the machining state of the crankshaft. 10... Bed, 11, 12... Headstock, 13
...Main shaft, 17, 18...Chuck, 21, 22
... Indexing table, 25, 26 ... Tool unit, 2
7, 28... Tool holder, 30... Processing tool, 5
4... Rotating body, 57... Spline shaft for synchronization, 6
7... Gripping arm, 83... Steady rest device, W...
...Crankshaft, J...Journal section.

Claims (1)

[Claims] 1. In a steady rest device that supports a plurality of journal parts on a crankshaft that is supported by a main shaft and rotationally driven, an indexing table movable in the axial direction of the crankshaft, and an indexing table provided on the indexing table around the axis of the crankshaft. a rotating body that is rotatably supported on and rotates synchronously with the main shaft; a plurality of gripping arms that are rotatably supported on the circumference of the rotating body and grip the raw journal portion of the crankshaft; a rotational drive device that applies rotational force to the gripping arm via a spring that biases it toward the gripping side; and a back-up device that engages with the gripping arm while gripping the unprocessed journal portion to prevent the gripping arm from retreating. A steady rest device comprising a back-up member.