JPS6212538Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a chuck for holding a crankshaft when grinding a crankpin part, and in particular, even if the amount of eccentricity of the crankpin changes, the journal support chuck relative to the center of rotation of the main shaft is adjusted according to the amount of eccentricity of the crankpin. This invention relates to a crankshaft holding chuck that can automatically change the setting of the center eccentricity.

Conventionally, when holding the crankshaft on the main shaft when grinding the crankpin part, an eccentric chuck was attached to the tip of the main shaft, and this eccentric chuck was used to hold the journal part of the crankshaft in an eccentric state. is positioned on the spindle rotation center line. In addition, the chuck is
In order to be able to hold crankshafts with different crankpin eccentricities with the same chuck, the eccentricity of the journal support part that supports the journal part of the crankshaft with respect to the center of rotation of the main shaft can be changed.

However, since the conventional setting of the eccentricity described above is manually performed, unless the number of rods of the same type of crankshaft to be ground is gathered to a certain extent, it is difficult to change the setting due to the change of the eccentricity. This has to be done frequently, which increases machine idle time and reduces machining utilization. Furthermore, it was impossible to meet the demand for randomly loading and machining crankshafts of different types (different amounts of eccentricity) into a machining system.

This invention solves the above-mentioned conventional problems, and its purpose is to automate the position indexing (setting change) of the crankpin to the main shaft rotation center as the eccentricity of the crankpin changes, and to To provide a crankshaft holding chuck that can be automatically processed by the same machine.

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

1 to 3 show an example of a crankshaft holding chuck according to the present invention, in which 1 is a main shaft head, 2 is a main shaft supported by the main shaft head 1,
A face plate 3 is integrally fixed to the front end surface of the main shaft 2, and a plate-shaped slide body 4 is arranged in front of this face plate 3, and this slide body 4 is bolted to the face plate 3 as shown in FIG. The crank pin 6a of the crankshaft 6 is slidably supported in the eccentric direction by guide members 5, 5, and the outer periphery of the slide body 4 and guide members 5, 5 is formed by a cylinder integrally attached to the face plate 3. It is covered by a shaped fixing member 7.

A chuck body 8 is integrally fixed to the front surface of the slide body 4 with bolts 9, and a support 10 for supporting the journal portion 6b of the crankshaft 6 is provided at the front end of the chuck body 8. The central axis l ₁ of the journal engaging portion 10a of 10
is eccentric from the rotational center line _l2 of the main shaft 2, and the clamp arm 12 is pivoted by a shaft pin 11 as shown in FIG. The upper end of the clamp arm is opposed to the journal part 6b which is engaged in the engaging part 10a of the support bar 10 from above via the presser foot 13 attached to the clamp arm. The lower end of 12 is connected to the clamp cylinder 1 provided on the chuck body 8.
It is connected to the piston rod 14a of No. 4 by a pin 15, and the journal portion 6b on the support metal 10 is clamped and unclamped by the forward and backward movement of the piston 14b.

In FIG. 1, reference numeral 16 indicates the crankshaft 6.
An indexing plate constituting a phase indexing mechanism for indexing the phase of the crank pin 6a on the spindle rotation center line _L2 , and this indexing plate 16 is concentric with the journal center axis _L3 of the support metal 10. Hollow indexing shaft 1 placed in
The indexing shaft 17 is rotatably and axially slidably attached to the chuck main body 8 via bearing members 18 and 19. A pin support plate 20 is integrally fixed to the side end of the pin support plate 20, and a reference pin 21 that engages with the crankshaft 6 is protruded from the front end surface of the pin support plate 20. A shifter 23 is attached to the shifter 23 which is engaged through a pin 22 so as to be relatively rotatable, and a pair of arms 2 extending in opposite directions are attached to the shifter 23.
The tip of one arm 24 is rotatably connected to the chuck body 8 via a pivot pin 26, and the tip of the other arm 25 is provided on the chuck body 8. connected to the piston rod 27a of the shift cylinder 27;
By moving the piston 27b of the shift cylinder 27 back and forth, the entire pin support plate 20 including the indexing shaft 17 is shifted in the axial direction of the indexing shaft 17, thereby making it possible to engage and disengage the reference pin 21 from the crankshaft 6. It's becoming like that. Further, at the other end of the indexing shaft 17, a universal joint 2 for allowing eccentricity is provided via a spline shaft 28, such as a Schmidt coupling.
The other end of the universal joint 29 is connected to a drive shaft 31 that is inserted through the center of the main shaft 2 and connected to an indexing drive source 30. Furthermore, a stepped portion 16a is formed on the index plate 16, and a positioning pin 3 that engages with this stepped portion 16a is formed on the index plate 16.
2 is fitted into a case 33 attached to the chuck body 8 so as to be slidable in the radial direction of the index plate 16, and the positioning pin 32 is attached in a direction in which it is pressed against the index plate 16 by a spring 34. Forced.

In FIG. 1, reference numeral 35 denotes a threaded shaft that is supported through the fixed member 7 in the moving direction of the slide body 4, allowing only rotation, and the threaded shaft 35 is an eccentric shaft of the crank pin 6a with respect to the axis of the journal. This screw shaft 35 is used to index the position of the crank pin so that it coincides with the rotation center of the main shaft according to the amount of eccentricity when machining crankshafts of different sizes.
The protrusion inside the fixing member 7 is screwed into the screw hole 36 formed in the slide body 4, and the fixing member 7 of the screw shaft 35 is screwed into the screw hole 36 formed in the slide body 4.
A head 38a of a drive shaft 38 of a nut runner 37 that rotates the screw shaft 35 in forward and reverse directions is removably engaged with the engagement hole 35a exposed to the outside. Reference numeral 37 is supported by a non-rotating part of a processing device (not shown) so as to be movable forward and backward relative to the screw shaft 35, and is used as the nut runner 3 when indexing the position of the crank pin with respect to the center of rotation of the main shaft.
7 is advanced, its drive shaft 38 is engaged with the screw shaft 35, and the screw shaft 35 is rotated to automatically perform the above position indexing. Further, between the reference surface 4a on the screw shaft engagement side of the slide body 4 and the inner reference surface 7a of the fixing member 7 facing parallel thereto, there is a crank pin 6a relative to the axis of the journal portion 6b.
A stepped spacer 39 for changing the setting is screwed to change the eccentricity d of the journal support portion center (center axis l ₁ ) of the support 10 with respect to the spindle rotation center line l ₂ in multiple stages, for example, in two stages, according to the eccentricity of the spindle rotation center line l 2 . The spacer 3 is interposed so as to be shiftable in a direction perpendicular to the axis 35.
9 is connected to a piston rod 40a of a spacer switching cylinder 40 provided on the chuck body 8, and is adapted to be shifted by operating the piston 40b to the forward end and backward end.

Next, the operation of the chuck of the present invention constructed as described above will be explained.

When the crank pin 6a of the crankshaft 6 is held on the main shaft 2 in a state in which it can be ground, the piston 14b of the clamp cylinder 14 is first moved backward to rotate the clamp arm 12 in the direction of the arrow A in FIG. 2, and the crank pin 6a is held in the unclamped state shown by the two-dot chain line.
The pin support plate 20 is moved backward by the shifter 23.
3, and the reference pin 21 is retracted so as not to interfere with the loading of the crankshaft 6 onto the main shaft.

In this state, the unprocessed crankshaft 6 is loaded into a processing position of a processing device (not shown), and the journal portion 6a of the crankshaft 6 is placed on the journal engagement portion 10a of the support metal 10. Thereafter, the piston 27b of the shift cylinder 27 is advanced to the state shown in FIG.
1 and 2, the reference pin 21 is engaged with the clamp shaft 6, and the center of the left spindle head (not shown) is moved forward to position the crankshaft 6 in the axial direction. . After that, the indexing drive source 30 is started to rotate in the forward direction, and the rotation is transmitted to the indexing shaft 17 via the universal joint 29 and the spline 28, and the indexing shaft 17, indexing plate 16, and pin support plate 20 are rotated. At the same time as the crankshaft 6 is rotated in the direction of arrow C in FIG. 1, the crankshaft 6 is also rotated in the same direction while being placed on the support metal 10. Then, the positioning pin 32 is inserted into the stepped portion 1 of the index plate 16 as shown in FIG.
6a, the forward rotation of the indexing drive source 30 is stopped, and the indexing drive source 30 is rotated slightly in the reverse direction to rotate the indexing plate 16.
The side surface of the stepped portion 16a is pressed against the positioning pin 32, thereby positioning the crank pin 6a on the rotation center line of the main shaft. and crank pin 6a
When the phase indexing is completed, the clamp cylinder 14 is moved forward to move the clamp arm 12 to the second position.
It rotates to the state shown by the solid line in the figure and clamps the journal portion 6b. At this time, if the eccentricity of the crank pin 6a with respect to the axis of the journal part 6b is d ₁ , the piston 40 of the spacer switching cylinder 40
b is moved to the forward end so that the second step portion 39a of the spacer 39 is aligned with the reference surface 4 of the slide body 4 and the fixing member 7.
a, 7a, and the screw shaft 3
5 is rotated by a nut runner 37 to slide the slide body 4 in the direction of arrow D in FIG. 1 until it is pressed against the spacer 39. In this way, the entire chuck body 8 is also moved in the direction of arrow D by the amount defined by the second step 39a of the spacer 39,
The amount of eccentricity of the journal support center of the support metal 10 with respect to the main shaft rotation center line _l2 is made to match the amount of eccentricity of the crank pin 6a with respect to the axis of the journal 6b. That is, the axis of the crank pin 6a is aligned with the main shaft rotation center line.
This means that it has been indexed to a position that matches l ₂ . Further, in a state where the spacer 39 is sandwiched between the reference surfaces 4a and 7a, the slide body 4 is accurately positioned, so that it becomes easy to ensure the positional accuracy of the journal support 10.

If the main shaft 2 is rotated in this state, the crankshaft 6 held by the main shaft will be rotated around the crank pin 6a. Therefore, if a rotating grindstone is pressed against the crank pin 6a, the crankshaft 6 will be rotated around the crank pin 6a. Pin 6a will be ground.

Also, if the eccentricity d ₁ of the crank pin 6a with respect to the journal portion 6b becomes smaller than that shown in FIG. 1 due to a change in the crankshaft 6 to be machined, first rotate the screw shaft 35 in the direction of loosening it with the nut runner 37. After separating the slide body 4 from the spacer 39 and removing the pressing force of the slide body 4 against the spacer 39, the spacer switching cylinder 40
The piston 40b is moved backward to pull out the second step 39a of the spacer 39 outside the reference surfaces 4a, 7a, so that only the first step 39b is interposed between the reference surfaces 4a, 7a. In this state, the nut runner 37 rotates the screw shaft 35 in the direction in which it is screwed into the screw hole 36 of the slide body 4, so that the reference surface 4a of the slide body 4 is aligned with the spacer 39.
Move it in the direction of arrow D in FIG. 1 until it is pressed against. Along with this, the entire chuck body 8 is moved by the same amount in the same direction as the slide body 4, and as a result, the eccentricity d of the journal support center of the support metal 10 with respect to the spindle rotation center line _l2 becomes small, and the crank pin 6a is moved at the center. The axis will be automatically indexed to a position that coincides with the spindle rotation center.

In the above embodiment, a case has been described in which the position of the spacer 39 is changed and the eccentricity of the journal support metal center relative to the main shaft rotation center is changed in two stages, but the invention is not limited to this, and the crankshaft to be machined The same applies to devices that can be switched to three or more stages depending on the number of types. in this case,
The spacer 39 has a multi-stage structure of three or more stages.

As described above, according to the present invention, the crankshaft is held on the main shaft by clamping the journal part at a position eccentric from the center of rotation of the main shaft, and the phase indexing mechanism makes it possible to index the phase of the crank pin. When changing the eccentricity of the journal support with respect to the spindle rotation center in response to a change in the eccentricity of the crankpin with respect to the journal axis, the spacer switching operation and the screw that adjusts the position of the chuck body with respect to the spindle axis are necessary. Since the rotation of the shaft is automated using a nut runner, it is possible to change the spacer and automatically change the eccentricity of the journal support metal center with respect to the spindle rotation center in multiple stages without requiring human intervention. Can handle automatic machining of crankshafts with different amounts of pin eccentricity. In addition, since the setting change of eccentricity is automated, idle time associated with setup change can be almost eliminated, which improves the utilization rate of processing equipment. Even when loaded, each crankshaft can be easily machined.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a crankshaft holding chuck according to the present invention, and FIG.
FIG. 3 is a cross-sectional view taken along the line - in FIG. 2, and FIG. 4 is an explanatory diagram showing the relationship between the index plate and the positioning pin in the present invention. DESCRIPTION OF SYMBOLS 1...Main shaft head, 2...Main shaft, 4...Slide body, 5...Guide member, 6...Crankshaft, 6a
...Crank pin, 6b...Journal part, 7...
...fixing member, 8...chuck body, 10...support metal, 12...clamp arm, 14...clamp cylinder, 16...index plate, 17...index shaft, 2
0... Pin support plate, 21... Reference pin, 23...
Shifter, 27... Shifter cylinder, 28... Spline shaft, 29... Universal joint, 31... Drive shaft,
32...Positioning pin, 34...Spring, 3
5...Screw shaft, 36...Screw hole, 37...Nut runner, 39...Spacer, 40...Spacer switching cylinder.

Claims (1)

[Scope of utility model registration request] A slide body is attached to the front end surface of the spindle of the spindle head so as to be slidable in the eccentric direction of the crank pin, a chuck body is integrally fixed to the slide body, and a chuck body is provided eccentrically from the axis of the spindle and is attached to the crankshaft. a support metal for supporting the journal portion; a phase indexing mechanism provided on the chuck body in alignment with the axis of the support metal for automatically determining the phase of the pin portion of the crankshaft; An indexing drive source connected to the indexing shaft via a universal joint and provided on the head side of the main shaft, supported by a fixed member fixed to the main shaft with only rotation allowed, and sliding on the slide body. A screw shaft that is screwed together from a direction that matches the direction of the chuck and adjusts the position of the chuck body with respect to the main shaft axis, a nut runner that is disposed to be removable from the screw shaft and that rotates the screw shaft, and A stage that is shiftably interposed in a direction perpendicular to the screw shaft axis between the slide body and the fixed member on the side, and that changes the eccentricity of the journal support metal center with respect to the main shaft rotation center in multiple stages according to the eccentricity of the crank pin. A chuck for holding a crankshaft, comprising a spacer with an attached spacer and a spacer switching device provided on the chuck body to operate the stepped spacer.