WO2002003044A1

WO2002003044A1 - Mass centering machine

Info

Publication number: WO2002003044A1
Application number: PCT/JP2001/005682
Authority: WO
Inventors: Tatsuya Ioka; Masami Matsuo
Original assignee: Nagahama Seisakusho Ltd.
Priority date: 2000-07-05
Filing date: 2001-07-02
Publication date: 2002-01-10
Also published as: JP3523573B2; JP2002018658A

Abstract

A mass centering machine, comprising a measuring station and a machining station separated from each other, the machining station further comprising a holding device capable of developing a high holding force so that a work is not rotated during the machining of the work and capable of being reduced in size and weight, wherein clamp claws (224) coming in point-contact with the work (W) or in line-contact axially with the work (W) are provided on the holding device of the machining station, whereby, even if the work (W) is forced to rotate, the clamp claws (224) bite into the work (W) to surely hold the work (W) with a small clamping force so that the work (W) is not rotated.

Description

Specification

Mass centering machine

Technical field

The present invention relates to a mass centering machine for forming a centering hole for centering as a processing reference in a rotating body such as a crankshaft for an automobile engine. Conventional technology

After the crankshaft for an automobile engine is integrally formed by forging or forging, it is first centered. In centering, a center hole is made at the position where the rotation axis of the crankshaft and the main axis of inertia coincide. The crankshaft with the center hole is then subjected to the necessary processing with the center hole as the processing standard.

Centering is performed by a device called a mass centering machine. An example of a mass centering machine is disclosed in Japanese Patent Application Laid-Open No. Sho. In the mass centering machine disclosed in this publication, when a work such as a crankshaft is held once, the unbalance is measured while the work is held, and a center hole is drilled based on the measurement result.

Another example of the mass centering machine is disclosed in Japanese Patent Application Laid-Open No. 2◦00-1211479. In this mass centering machine, a measurement station that measures the unbalance of a work and a processing station that drills a center hole for a workpiece are separated, and measurement and processing based on the measurement result are performed in parallel. This can be done for multiple workpieces.

The present invention relates to an improvement of a mass centering machine in which a measuring station and a processing station are separated as in the latter.

In a mass centering machine, a holding device for holding a work is indispensable in order to measure the unbalance of the work and make a hole in the center for a peak. When drilling a center hole in the work, make sure that the work piece is held firmly so that the work does not move or rotate due to the torque generated when drilling a hole in the center with a drill etc. No. For this reason, a holding device with a strong holding force is necessary. Therefore, there was a problem that it was difficult to reduce the size and weight of the holding device.

In particular, in a mass centering machine in which the measuring station and the processing station are separated, the holding device of the measuring station does not need to have a strong holding force, but the holding device of the processing station must have a strong holding force. Due to the difference in the holding force, there is a possibility that the holding position of the work may be slightly shifted.

On the other hand, in the measuring station, in order to increase the measurement accuracy of the unbalance, the holding device is designed to be lightweight, and the holding device holds the work with a relatively small holding force. By the way, the work processed by the mass centering machine is a state formed by forging or forging without any processing as described above, and the surface of the workpiece is a rough surface covered with a so-called black scale. It is. For this reason, when the work is held by the holding device of the measuring station, the holding force is weak, and there is almost no holding mark on the work surface. However, when the work is held by the holding device of the processing station, the holding force is reduced. Due to the fireflies, retention marks are left on the work surface. Strictly speaking, the holding state in the measurement station is slightly different from the holding state in the force p station, and it is difficult to improve the accuracy when drilling a hole in the center based on the measurement results. 7 Disclosure of the invention

The present invention has been made to solve the above problems.

An object of the present invention is to provide a mass centering machine capable of realizing a small and lightweight holding device in a processing station.

Another object of the present invention is to provide a mass centering machine capable of forming a holding mark on a work surface at a measuring station and accurately holding exactly the same position at a processing station.

The invention according to claim 1 includes a measuring station for measuring the unbalance of a workpiece rotating about an axis, and a processing station for at least drilling a hole in the workpiece based on the measurement result. A machining center provided with a holding device for holding a workpiece, wherein the processing station comprises: The mass centering machine is characterized in that the placement includes a clamp claw that makes point contact with the workpiece.

In the invention according to claim 2, the holding device is configured such that, when the work is viewed in the axial direction, a pair of seating surfaces for receiving the work from diagonally below left and right; 2. The mass-sensing ring machine according to claim 1, further comprising a pair of claws for holding the work by making point contact with the work surface obliquely from above and to the left when viewed in the direction.

The invention according to claim 3 is the mass centering machine according to claim 2, wherein the holding device has a drive source for driving a pair of clamp claws. The clamp claw has a shape that makes point contact with the surface of the work when viewed in the axial direction of the work, and has a shape that makes linear contact with the surface of the work when viewed in a direction perpendicular to the axial direction of the work. 2 is a mass centering machine described in 2.

The invention according to claim 5 is the mass sensor ring machine according to claim 4, wherein the clamp claw has a shape that is convexly curved downward when viewed in a direction orthogonal to the axial direction of the workpiece. .

The invention according to claim 6 is the mass centering machine according to claim 4, wherein the clamp claw has a shape protruding downward in a rectangular shape when viewed in a direction orthogonal to the axial direction of the workpiece. is there.

The invention according to claim 7 is the mass centering machine according to claim 1 or 2, wherein the clamp claw protrudes downward in an inverted triangular pyramid shape and has a sharp lower end.

According to an eighth aspect of the present invention, there is provided a measuring station for measuring unbalance of a work rotating about an axis, and a processing station for making at least a center hole in the work based on the measurement result. A mass centering machine having a pre-processing station for performing pre-processing on a workpiece before measuring unbalance at a measuring station, wherein the pre-processing station has a pair of a pre-processing station for holding the workpiece. A holding device is provided, and each holding device holds a workpiece. A pair of seating surfaces and a pair of clamps are included. The pair of seating surfaces can respectively receive the workpiece from obliquely below, and the pair of clamps are provided to face the pair of seating surfaces. This is to hold down the work from the opposite side to the received part so that the work received by the seating surface is pressed against the seating surface.Furthermore, the work received by the pair of seating surfaces makes contact with the seating surface. This mass-sensing ring machine is equipped with a work holder that presses the work from above to below so that the surface of the work to be seated is marked.

The invention according to claim 9 is the mass centering machine according to claim 8, characterized in that the pretreatment station is incorporated in the measurement station.

According to the configuration of the present invention, the holding device for the aesthetic treatment includes a crimping claw that makes a point contact or a line contact with the workpiece in the axial direction. The peak is subjected to axial thrust and rotational torque during machining to make a hole in the center. Clumph. The claws make point contact with the workpiece when the workpiece is viewed in the axial direction. Therefore, when the axial thrust and the rotational torque are applied to the work, the clamp claws that come into contact with each other work to bite into the workpiece surface, and the work tries to rotate against the axial thrust and the rotational torque. And hold the work firmly.

As described above, the clamp claw makes point contact or linear contact with the workpiece in the axial direction of the workpiece, so that the clamp claw applied to the clamp claw may be small. Accordingly, it is possible to reduce the size and weight of the hydraulic unit, air unit, and solenoid unit that provide clamps, and to reduce the size and weight of the entire holding device. According to the configuration of claim 8, in the pretreatment station, the workpiece is pressed against the seating surface by the work holder, and a seating mark is formed on the work surface. Therefore, when the workpiece is repeatedly held, the trace of seating is received, and the reproducibility of seating is improved. In addition, since the seating marks are formed on the surface of the work in the pre-processing station, the work can be held in the measuring station and the processing station in the same holding state. Therefore, the accuracy of mass centering is improved.

According to the configuration of claim 9, the processing performed by the pre-processing station can be performed in the measurement station, so that the configuration is simpler, and the reproducibility of seating can be improved. In addition, the accuracy of measurement repetition and the accuracy of mass centering are improved. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a block diagram showing a mass centering machine according to one embodiment of the present invention.

FIG. 2 is a partially cutaway front view showing a measuring station of the mass centering machine.

FIG. 3 is a cross-sectional view of the measuring station taken along line Ι-III in FIG.

FIG. 4 is a cross-sectional view showing the operation of a clamp member in the above-described self-measurement station for keeping the gripping angle of a crankshaft as a rotating body constant.

FIG. 5 is a sectional view showing an outer diameter measuring station of the mass centering machine.

FIG. 6 is a front view showing a processing station of the mass centering machine. FIG. 7 is a sectional view of the processing station.

FIG. 8 is a perspective view of the combined cutting tool attached to the processing spindle of the processing station.

FIG. 9 is a diagram for explaining a problem in the holding device of the heating station 2.

FIG. 1◦ is a diagram showing a configuration of a holding device according to an embodiment of the present invention in a heating station.

Figure 11 shows the seating surface and crimp of the holding device at the processing station. FIG. 3 is a diagram for explaining a configuration of a nail.

FIG. 12 is an illustrative view showing a modified example of the clamp claws of the holding device in the processing station.

FIG. 13 is a diagram showing a configuration of a measuring device according to an embodiment of the present invention in a measuring station. Embodiment of the Invention

Hereinafter, a mass centering machine according to an embodiment of the present invention will be specifically described.

First, the configuration and operation of the entire mass centering machine will be described. The mass centering machine in this example is for centering the crankshaft Cs as a rotating body, and as shown in FIG. 1, the deviation of the crankshaft Cs between the rotation axis and the main axis of inertia is determined. A measuring station 1 for measuring the condition and a center hole for centering as a machining reference formed at the center of inertia of the crankshaft Cs obtained from the measurement result by the measuring station 1 or at a predetermined position in the vicinity thereof. In this example, the outer diameter of both shaft end portions C s 1 and C s 2 of the portion to be processed of the crank shaft C s is disposed between the two stations 1 and 2. The outer diameter measuring station 3 to be measured and the crankshaft Cs are machined from the unprocessed crankshaft Cs supply section through each station 1 to 3 while maintaining their postures almost constant. Class A transport unit 6 that transports the ink shaft Cs to the take-out unit 5 and a control unit 7 that controls the operation of each of the above units are provided.

As shown in FIGS. 2 and 3, the measurement station 1 includes a base 11, a vibration frame 13 supported on the base 11 by a plurality of springs 12, and a vibration frame 13. 13 Hold both ends C s 1 and C s 2 of the crank shaft C s arranged on the top of the shaft 3, and rotate the crank shaft C s synchronously with the crank shaft C s fixed at a fixed holding angle. A pair of rotating body gripping disks 14 and 14, and a vibration detector 15 for measuring the vibration of the vibration frame 13 generated by the synchronous rotation of the pair of rotating body gripping disks 14 and 14. It has.

In these figures, reference numeral 16a denotes a motor for synchronously rotating the pair of rotating body holding disks 14 and 14, and the rotation of the motor 16a is performed by the belt 16b and the vibration frame. The rotating body gripping disks 14 and 14 are transmitted to the rotating body gripping disks 14 and 14 via the shaft 16 c and the belts 16 d and 16 d arranged in 13 and the two rotating body gripping disks 14 and 14 are It is rotated synchronously. Although the motor 16a is mounted on the base 11 in the figure, it may be mounted on the vibration frame 13. If the motor 16a is mounted on the vibrating frame 13, the belt 16b straddling the base 11 and the vibrating frame 13 can be omitted. Is further improved.

The rotating body gripping disks 14 and 14 respectively hold a pair of drive heads 17 and 17 slidable in a direction parallel to the rotation axis C s X of the shaft C s on the vibration frame 13. It is rotatably supported on 17. By rotating the screw 17a attached between the vibration frame 13 and the drive head 17 to adjust the distance between the two drive heads 17 and 17, a pair of rotation The spacing between the body gripping disks 14 and 14 can be adjusted according to the size (length) of the crankshaft Cs to be measured.

Also, as shown in FIG. 3 showing the shaft end C s1 side, the rotating body gripping disks 14 are at the stop position (the position in FIG. ), A pair of work receivers 14 a, 14 a supporting the shaft end C s 1 from below, and the shaft end C s with respect to these two work receivers 14 a, 14 a. 1 and are rotatable to open and close each other as shown by the solid line and dashed line in the figure.The shaft ends between the work receivers 14a and 14a in the closed state shown by the solid line A pair of clamp arms 14b and 14b for holding and fixing the portion Cs1 are provided. The two surfaces of the work receivers 14a and 14a that abut against the shaft end Cs1 are positioned at the time when the crankshaft Cs is fixed by gripping the shaft end Cs1. The reference plane is set as the reference plane. The same applies to the vehicle end C s 2 side.

The mechanism for rotating and opening the clamp arms 14b, 14b as described above is not shown, but may be incorporated in the rotating body gripping disk 14, for example, or the drive head 1 The clamp arms 14b and 14b may be pivotally opened and closed via a transmission mechanism such as a cam by assembling them in the inside 7 or on the vibration frame 13. The holding force by the clamp arms 14b and 14b may be a relatively small force, and the holding force may be generated by a spring.

In addition, above the crankshaft C s between the pair of rotating body gripping disks 14 and 14, it is possible to move up and down as shown by the black arrow in FIG. 2 and to show the white arrow in FIG. 4 (a). In order to define the gripping angle of the crankshaft Cs with respect to the rotating body gripping disks 14 and 14 by moving the crankshaft Cs3 from left and right in the direction shown by Specifically, as shown in FIG. 4 (b), the first crankpin Cs3 is defined so as to be located directly above the shaft end Cs1 (and the shaft end Cs2). , A pair of Lamp members 19 and 19 are arranged.

Further, a push rod mechanism 18 for positioning and fixing the crankshaft Cs in the direction of the axis is arranged in one of the drive heads 17. Referring to FIG. 2, the push rod mechanism 18 includes a cylindrical sleeve 18 a slidably disposed in the axial direction of the crankshaft C s with respect to the drive head 17. The rotating body gripping disk 1 is passed through the sleeve 18a and is rotatably held with respect to the sleeve 18a via flanges 18b and 18b provided before and after the sleeve 18a. A push rod 18 c arranged coaxially with 4 and, although not shown, the sleeve 18 a is moved in the axial direction of the crankshaft C s with respect to the horse head 17. Moving means.

By operating the above-described parts based on a control signal from the control means 7 as follows, the crankshaft Cs is gripped by the pair of rotating body gripping disks 14 and 14 at a fixed gripping angle. After being fixed, the pair of rotating body gripping disks 14 and 14 are rotated synchronously, and the state of displacement of the rotating shaft C s X and the inertia main shaft of the crankshaft C s is measured.

That is, first, with the clamp arms 14b, 14b of the two rotating body gripping disks 14, 14 open from each other as shown by the dashed line in FIG. 3, the transport shown in FIG. When the means 6 is operated, the unprocessed crankshaft C s is conveyed from the supply unit 4 by the conveying means 6 and the shaft ends C s 1 and C s 2 are moved to both rotating body holding disks. 14 and 14 are placed on the respective work receivers 14a ...

Next, a pair of cranks from above the crankshaft Cs. The member 19. 19 is lowered, and then the clamp members 19, 19 are moved synchronously left and right as shown by white arrows in FIG. 4 (a), and the first crank pin Cs 3 is moved. When sandwiched from the left and right, as shown by the black arrow in FIG. 4 (b), the crankshaft Cs is brought into contact with the abutting surfaces of the workpiece supports 14a. s KC s so that the first crank pin C s 3 is located directly above the shaft end C s 1 (and the shaft end C s 2) as shown in FIG. In addition, the grip angle is defined.

Next, while maintaining this state, the sleeve 18a of the push rod mechanism 18 is advanced in the direction of the crankshaft Cs, and the tip of the push rod 18c is moved to one side. When pressed against the end face of the shaft end C s 1, the end face of the opposite shaft end C s 2 comes into contact with the reference surface 14 c provided on the other rotating body gripping disk 14, and the crankshaft C s is positioned in the direction of its axis and fixed in the same direction. In this case, push rod 18 Is rotatably held with respect to the sleeve 18a as described above, and therefore does not hinder the rotation of the crankshaft Cs for measurement described later.

Almost simultaneously with the operation of the push rod mechanism 18, the pair of clamp arms 14 b and 14 b on the two rotating body gripping disks 14 and 14 are shown by solid lines in FIG. When the shaft ends C s 1 and C s 2 are gripped from two directions by two sets of workpiece receivers 14 a and clamp arms 14 b respectively, the crankshaft C s becomes a pair. The rotating body gripping disks 14 and 14 are fixed in a direction perpendicular to the axis thereof.

Then, next, after opening the clamp members 19, 19 and retreating upward, the motor 16a is driven, and the pair of rotating body gripping disks 14, 14 are synchronously rotated at a high speed. Using the vibration detector 15 to measure the vibration generated in the vibration frame 13, the measured data shows the displacement between the rotation axis C s X of the crankshaft C s and the main axis of inertia in the same manner as before. Is required.

Specifically, by comparing the vibration waveform measured using the vibration detector 15 with the rotation angle of the crankshaft Cs, the direction and distance of the displacement of the inertia main shaft with respect to the rotation axis CsX are determined. Is calculated.

This operation is also performed automatically by the control means 7, and the measurement result is stored in the control means 7.

Next, the crankshaft Cs for which the measurement has been completed is sent to the outer diameter measuring station 3 for measuring the outer diameters of both shaft end portions Cs1 and Cs2, which is the next step, by the conveying means 6. . At the same time, a new unprocessed crankshaft Cs is carried into the measuring station 1 from the supply unit 4 by the above-mentioned conveying means 6.

Then, in parallel with the outer diameter measurement of the previous crankshaft Cs by the outer diameter measuring stage 3, a new crankshaft Cs is measured by the measuring station 1 in the same manner as described above. As shown in FIG. 5, the outer diameter measuring station 3 includes a V block 31 on which the shaft end C s 1 of the crankshaft C s (the same applies to the shaft end C s 2) and a V block 3 1. The two reference planes 31a and 31a are arranged in parallel with each other, and as shown by the white arrow in the figure, in a direction orthogonal to the reference planes 31a and 31a. Two measuring plates 3 3, 3 3 that can be translated by the movement of the air cylinders 3, 3 2, and these two measuring plates 3 3, 3 3, and the reference surface 3 of the two surfaces of the V block 3 1 A pair of differential transformers 34.34 for measuring the distance from 1a and 31a is provided.

Further, a pair of clamp members 35, 35 are provided above the V block 31, similarly to the above-described measuring station 1. The clamp members 35, 35 are attached to the work blocks 14 a, 1 a in the previous measurement station 1 with respect to the two reference surfaces 31 a, 31 a of the V block 31. 4 The contact surface (reference surface) and crump of a. The members are arranged so as to coincide with the positional relationship between the members 19 and 19.

So this crump. When the first crankpin Cs3 of the crankshaft Cs is sandwiched in the same manner as described above by using the members 35, 35, the crankshaft Cs becomes the reference surfaces 31a, 31 With respect to a, the work receivers 14a and 14a are placed on the V-block 31 at exactly the same angles as the angles of the work receivers 14a and 14a with respect to the contact surface.

Then, in this mounted state, the air cylinders 32, 32 are operated, and as shown by the two-dot chain line in the figure, the two measurement plates 33, 33 are moved to the shaft end C sl of the crankshaft C s. When the distance between the two measurement plates 33, 33 and the reference planes 31a, 31a is measured using the differential transformers 34, 34, the shaft end The diameter of the portion C s1 (and the shaft end C s2) in two directions with the above-mentioned two reference surfaces 31 a and 31 a as measurement standards is obtained.

This operation is also automatically performed by the control means 7, and the measurement result is stored in the control means 7.

Next, the crankshaft C s for which the measurement has been completed is sent again by the conveying means 6 to the next step, the aesthetic treatment section 2. At the same time, the next crankshaft Cs is carried into the outer diameter measuring station 3 by the above-mentioned carrying means 6. At the same time, a new unprocessed crankshaft Cs is also carried into the measuring station 1 from the supply unit 4 by the conveying means 6.

In parallel with the machining of the previous crankshaft Cs by the machining station 2, the outer diameter measurement of the next crankshaft Cs by the outer diameter measuring station 3 and the new crankshaft Cs by the measuring station 1 Is measured. As shown in FIG. 6 and FIG. 7, the machining station 2 has a pair of shaft ends Cs1 and Cs2 for holding and fixing both shaft ends Cs1 and Cs2 of the crankshaft Cs on the base 21. Fixing means 22 and 22 are provided. The two fixing means 22 and 22 are respectively fixed on a pair of processing heads 20 and 20 arranged on the base 21.

As shown in FIG. 7 showing the shaft end C s1 side, each fixing means 22 includes a pair of work receivers 22 a and 22 a supporting the shaft end C s 1 from obliquely below. The two work receivers 22a and 22a are disposed diagonally above and below the shaft end Cs1 so as to be pivotally openable and closable. , 22a for gripping and fixing the shaft end Cs1. The two surfaces of the work receivers 2 2 a and 22 a that abut on the shaft end C s 1 are positioned at the time of gripping the shaft end C s 1 and fixing the crankshaft C s. The reference plane is set as a reference. The same applies to the shaft end C s2 side. Each work receiver 22a is a linear motion guide having a force mechanism, which is driven by a driving force transmitted from a servomotor 22b via a gearbox 22c and a shaft 22d. By 2 e, it is possible to move in the direction shown by the black arrow in FIG. 7, whereby both shaft ends C s 1 and C s 2 are placed on each work receiver 22 a. The gripping position of the crankshaft Cs thus set can be finely adjusted in a direction orthogonal to the axis thereof.

Also, above the workpiece holders 22a and 22a and the clamp arms 22b and 22b on the shaft end Cs1 side, the left and right sides are synchronized in the direction indicated by the white arrow in FIG. By rotating and opening and closing and holding the first crank pin Cs 3 from the left and right, the grip angle of the crankshaft Cs is set to the same angle as the rotating body gripping disk 1.14 of the measuring station 1, that is, 1) A pair of clamp members 22 f and 22 f for defining the angle at which the crank pin C s 3 is located immediately above the shaft end C s 1 (and the shaft end C s 2). In this case, as shown in FIG. 6, the force of the second crankpin Cs4 abuts against the pin weight Cs5 from the side thereof, and the counterweight Cs5 is applied to the shaft end. A push bar 22g for pressing in the direction of Cs2 is arranged. Of the above, the clamp arms 22b and 22b are opened and closed by the driving force from the hydraulic cylinders 22h and 22h, respectively, disposed behind them. In addition, the clamp members 22 f and 22 f are the right clamps in FIG. 7 by the operation of the hydraulic cylinder 22 i arranged above them. The member 22 f is pivotally opened and closed, and the left clamp member 22 f is pivotally opened and closed by a gear mechanism (not shown). Furthermore, the push bar 22g is actuated by a hydraulic cylinder 22j, also located above it.

Behind the fixing means 1, 1, a center hole is formed at the end face of each of the two shaft ends C s 1, C s 2, and other holes are formed at the two shaft ends C s 1, C s 2. Processing spindles 23a and 23a for processing are arranged. The machining spindles 23a, 23a are rotationally driven by motors 23b, 23b disposed at the rear. Also, the above machining spindles 2 3 a, 2 3 & and motor 2 3 13,

23 b is disposed on the machining head 20 so as to be able to move back and forth in a direction parallel to the rotation axis C s X of the crankshaft C s via the linear motion guides 23 c and 23 c. The order of the machining accuracy of the two shaft ends C s 1 and C s 2 in the above direction by the ball screws 23 e and 23 e driven by the servo motors 23 d and 23 d, respectively. It is moved back and forth with precision.

Machining spindle 2 on the shaft end C s1 side of both load spindles 2 3a and 2 3a

In this example, the combination cutting tool 8 shown in FIG. 8 is attached to 3a. Such a combination cutting tool 8 includes a drill 81 for machining a center hole, an outer diameter cutting tool 82 for turning the outer peripheral surface of the shaft end C s 1 to roughly cut the outer diameter of the shaft, and a shaft end. This is a combination with an end face cutting tool 83 for turning the end face of C s 1 to adjust the axis length.

On the other hand, although not shown, the machining spindle 23 a on the side of the shaft end C s2 is formed by turning the outer peripheral surface of the drill 81 for center hole processing and the shaft end C s 2 among the above. Combined cutting tool 8 combined with outer diameter cutting tool 8 2 for rough cutting of shaft outer diameter Be attached.

Then, the end faces of both shaft end portions C s1 and C s 2 are formed by a single hole and the outer diameter of the shaft is roughly cut by the two combined cutting tools 8, and one shaft end portion C s 1 Is cut to adjust the axial length.

In addition, by using the same combined cutting tool 8 shown in FIG. 8 for machining both shaft end portions C s KC s 2, the other shaft end portion C The end face of s2 may also be cut off.

In addition, for machining both shaft ends C s1 and C s2, only center hole machining may be performed. In this case, the combination of the spindles 23 a and 23 a is performed as described above. It is sufficient to mount a drill for processing a single hole in the center instead of a sharpening tool.

In the heating station provided with the above components, first, as described above, the crankshaft Cs in which the outer diameters of both shaft ends Cs1 and Cs2 are measured in the outer diameter measuring station 3 is described. Before being transported by the transporting means 6, based on the measurement and result by the measuring station 1 described above and the measurement result by the outer diameter measuring station 3, the gripping position of the crankshaft Cs is In order to make fine adjustments in the direction orthogonal to each other, the positions of the work receivers 22a are moved by a predetermined amount.

That is, based on the measurement result by the measuring station 1, the machining center of the drill 81 for the center one-hole machining of the combined cutting tool 8 coincides with or is close to the center of inertia of the crankshaft Cs. In order to finely adjust the gripping position of the crankshaft Cs in a direction perpendicular to the axis of the crankshaft Cs so that the imbalance correction in the subsequent process is within an easy range, The position is moved.

At this time, finish processing of each part such as both shaft end parts Cs1, Cs2, center journal part and crankpin part with reference to one center hole formed in the esthetic station 2. In order to prevent the so-called black scale residue from being generated on each of the above-mentioned finished surfaces of the crankshaft C s which is commercialized through the subsequent steps, the outer diameter is measured by the outer diameter measuring step 3 described above. In consideration of the result, the range in which the fine adjustment of the gripping position of the crankshaft Cs is performed may be limited.

That is, as described above, the crankshaft Cs is integrally formed by forging or forging, and the surface before processing is a rough surface with low dimensional accuracy. So usually, However, if the processing allowance is smaller than the planned thickness, depending on the degree of fine adjustment, even after finishing, So-called black scale may remain.

It is best to measure all dimensions of the crankshaft CS before machining in order to prevent force and dark skin residue, but this would complicate the outside diameter measuring station 3 and increase the time required for measurement. And the productivity of the crankshaft Cs may decrease.

Therefore, in this example, the thickness of the machining allowance of the outer peripheral surfaces of both shaft end portions Cs1 and Cs2 of the crankshaft Cs is set to be smaller than the thickness of the machining allowance of the other portions. When the outer diameter of the shaft ends C s1 and C s2 is measured representatively by the outer diameter measuring station 3 as shown in the above, and the measurement results show that the machining allowance is smaller than the planned thickness In this case, the range for fine adjustment is limited to the range obtained by subtracting the small amount.

According to this method, if the range of fine adjustment is limited so that no black scale remains on the outer peripheral surfaces of both shaft ends C s1 and C s2, the shaft ends C s1 and C s Black scale can be prevented from remaining in other portions where the thickness of the processing margin is set to be larger than s2.

In this embodiment, in the fine adjustment, the measurement results obtained in the measurement station are used, and a large number of crankshafts Cs obtained in the subsequent process are corrected in the final unbalance correction. By feeding back the balance distribution data and intentionally shifting the center hole forming position on the end faces of both shaft ends C s 1 and C s 2 by a predetermined amount from the center of inertia in a predetermined direction, The center of the unbalance distribution of the multiple crankshafts Cs may be moved to any position, particularly a position suitable for correcting the unbalance.

That is, as described above, in the centering of the crankshaft C s, the position that can be corrected, that is, the counterweight that can be drilled for correction is basically a crank pin (No. 1 Crank pin C s 1 and the last crank pin).

For this reason, for example, in the case of the first crankpin Cs3 shown in FIGS. 1 In order to have a position for drilling the counter weight C s 6 of the crank pin C s 3, the position where the center hole is formed on the end faces of both shaft end parts C s 1 and C s 2 from the center of inertia It is preferable to shift in the direction of the counterweight Cs6.

These series of operations are based on the measurement results previously stored in the control means 7, the present measurement results, and the data of the unbalance distribution fed back from the final unbalance correction machine. Automatically done by 7.

Next, as described above, after the movement of the positions of the respective work receivers 2 2a... To finely adjust the gripping position of the crankshaft Cs, the clamp arms 2 2b and 2 2b were opened. In this state, when the transporting means 6 (not shown) is operated, the crankshaft C s for which the diameter measurement has been completed at the outer diameter measuring station 3 is transported, and its shaft end C s 1, C s 2 is placed on each of the workpiece holders 2 2a... Of both fixed parts 22, 22.

Next, the clamp members 2 2 f and 2 2 f are rotated left and right synchronously as shown by the white arrow in FIG. 7, and the first crank pin C s 3 is sandwiched from the left and right. The shaft C s rotates along the outer peripheral surfaces of the two shaft ends C s 1 and C s 2 abutting on the abutting surfaces of the respective lock receivers 22 a. The same angle as the rotating body gripping disks 14 and 14 of the measuring station 1, that is, the angle at which the first crank pin Cs3 is located directly above the shaft end Cs1 (and the shaft end Cs2). Stipulated.

Next, while maintaining this state, the push bar 22 g is operated, and its tip is brought into contact with the side of the counterweight Cs 5 of the second crankpin Cs 4, and the opposite side The end face of the shaft end C s 2 comes into contact with the reference plane of the reference 22 k provided on the other fixing means 2, and the crankshaft C s is positioned in the direction of its axis, and in the same direction. Fixed.

At about the same time as the operation of the push bar 22 g, the pair of clamp arms 22 f and 22 f of each of the fixing means 22 and 22 are closed as shown by the solid line in FIG. When two sets of workpiece receivers 2 2a and two clamp arms 2 2f hold the shaft ends C s 1 and C s 2 from two directions, the crankshaft C s becomes a pair of fixing means 2. 2, 2 are fixed in the direction perpendicular to the axis. Then, while rotating the combined cutting tool 8 of the machining spindles 23a and 23a, When the processing spindles 23a and 23a are respectively advanced in the direction of the end faces of both shaft ends Cs1 and Cs2, first, the drill 81 of the combined cutting tool 8 is used. However, as described above, a centering hole for centering is formed at a predetermined position at or near the center of inertia, which serves as a machining reference. Then, both shaft ends C s and C are formed by an outer diameter cutting byte 82. The outer peripheral surface of s 2 is turned to rough-cut the outer diameter of the shaft, and the end faces of both shaft ends C s KC s 2 are turned by the end face cutting tool 83 to adjust the shaft length. .

Note that such processing may be performed using cutting tools mounted on different processing spindles under conditions suitable for each cutting tool. However, as described above, if each processing is performed at a time using one combined cutting tool 8, there is an advantage that the structure of the processing station 2 can be simplified. The processing in the processing station 2 is not limited to the above three types, and other processing may be performed on the processing station 2.

After the processing is completed, when the conveying means 6 is operated again, the processed crankshaft Cs is conveyed to the take-out part 5, where it is taken out and sent to the next step. At the same time, the next crankshaft Cs is carried into the heating station 2 by the above-mentioned conveying means 6, and the next crankshaft Cs is carried into the outside diameter measuring station 3 and a new unprocessed work is performed. Is carried into the measuring station 1 from the supply unit 4, and the respective operations are performed in parallel at the respective stations 1 to 3.

Next, with reference to FIG. 9, a problem in the holding device of the additional esthetic 2 (see FIG. 7) will be described.

The holding device of the heating station 2 includes a pair of workpiece receivers 22a and a pair of clamps. Member 22f is included. Both ends C s 1 and C s 2 (hereinafter referred to as “work W”) of the crankshaft are received from a diagonally lower position by a pair of work receivers 22 a when viewed in the axial direction, respectively. It is pressed and held from obliquely above by the clamp member 22f.

In order to prevent the workpiece W held by this holding device from rotating due to the torque applied during machining such as drilling a center hole, a very A strong clamping force was required. For this reason, the hydraulic unit that drives the clamp member 22 f required a large, heavy-weight, high-pressure type. In addition, there is a problem that the seating surface 222 of the work receiver 22a, which receives a very strong clamping force, is liable to be worn and easily damaged.

Therefore, as shown in FIG. 10, in this embodiment, the work receiver 22a and the seating surface 222 of the holding device adopt the same configuration (the same configuration as the conventional one) as shown in FIG. The claws 2 24 of the member 22 f that hold down the work W are formed as clamp claws 2 24 that make point contact with the surface of the work W when viewed in the axial direction of the work W.

More specifically, a pair of holding devices 2 are provided so as to hold both ends of the work W. Each holding device 2 includes a pair of work receivers 22a and a pair of clamp members 22f. A seating surface 222 on which the workpiece W is seated is formed in each workpiece receiver 22a. Each of the pair of seating surfaces 2 2 2 can receive the mark W from diagonally below. Each of the pair of clamp members 22 f is provided with a clamp claw 224. Each of the clamp claws 22 has a shape that makes point contact with the workpiece W when viewed in the axial direction of the workpiece W.

With this configuration, even if the clamping force of the clamp member 22 f is smaller than that of the related art, the work W can be held so that the torque W received during machining does not rotate the workpiece W. This makes it possible to reduce the size and weight of the hydraulic unit for driving the clamp member 22f. Of course, even if the clamp members 22 f move in horses, it is possible to reduce the size and weight of the units even if they are air units and solenoid units.

When the clamp claw 22 is shaped so as to make point contact with the workpiece W when viewed in the axial direction of the workpiece W as described above, the clamp can be crimped even with a small clamping force. Claws 2 2 4 bite into the surface of Park W. Then, the work W is prevented from rotating by the torque.

FIGS. 11A and 11B are diagrams for explaining the configuration of the seating surface 222 and the clamp pawls 222, where A is a diagram viewed in the axial direction of the workpiece W, and B is a diagram viewed in a direction perpendicular to the axis of the workpiece W. FIG. As shown in FIG. 11A, when viewed in the axial direction of the work W, the clamp claws 222 have a shape that makes point contact with the surface of the work W. On the other hand, the work W When viewed in the cross direction, the clamp claws 2 24 are in line contact with the workpiece W in the axial direction, as shown in FIG. 11B. If the clamp claw 2 2 4 is formed in such a shape, when the work W tries to rotate around the axis, it will be cramped. The claws 2 2 4 bite into the surface of the work W, and the rotation of the work W is reliably prevented.

FIGS. 12A, 12B, and 12C are all illustrative views showing modified examples of the clamp pawls 224. 12A, 12B and 12C show a state where the clamp claw 224 is viewed in a direction perpendicular to the axial direction of the workpiece W. Each of the clamp claws 224 shown in FIGS. 12A, B, and C has the same shape as the clamp claws 224 shown in FIG. 11A when viewed in the axial direction of the workpiece W.

The clamp claw 2 24 shown in FIG. 12A has an inverted triangular shape and has a sharp lower end. In other words, the clamp claw is a claw protruding downward in an inverted triangular pyramid shape.

FIG. 12B shows a clamp claw 222 having a shape convexly curved so as to swell downward. FIG. 12C shows the claws 224 in which the center portion in the width direction (axial direction of the workpiece W) projects downward in a rectangular shape.

Each of the clamp claws 2 2 4 makes line contact with the surface of the work in the axial direction of the work, so that the claws bite into the surface of the work W and rotate the work W in the same manner as the clamp claws 22 described in FIG. Is definitely blocked.

The shape of the clamp claw according to the present invention is not limited to the above-described embodiment. In short, any shape may be used as long as the clamp claw makes point contact with the work or linearly contacts the work in the axial direction.

Next, the holding device in the measuring station 1 will be described.

As described with reference to FIG. 3, the holding device in the measuring station 1 is also basically the same as the holding device in the machining station, and includes a workpiece holder 14a of 1f and a pair of clamp arms. 14b, and a pair of holding devices are provided to hold both ends of the work. .

More specifically, as shown in FIG. 13, each holding device includes a pair of peak receivers 1a and a pair of clamp arms 14b. A seating surface 11 for seating the work W is formed on the work receiver 14a. Each of the pair of seating surfaces 141 can receive the work W from obliquely below. Each of the pair of clamp arms 14 b is provided with a clam claw 12. Clamp ° Claw 14 2 is provided opposite to seating surface 14 1, and from the opposite side to the received portion so as to press work W received on seating surface 14 1 against seating surface 11 1 Hold down work W.

By the way, the clamp that generates the clamp claws 1 and 2 is the cramp in the station 2. Claw 2 2 3 crump 'power is small compared to force.

Therefore, in this embodiment, the work W is received by the seating surface 141, and the work W is received. In the state of being held down by the claws 14 2, furthermore, by the pressure holding 1550, the pressure W is pressed down from above and comes into contact with the seating surface 1 4 1. A trace of seating was made on the covered rough surface.

The work holder 150 that pressed the work W so as to make a trace of seating on the work W is then lifted upward. Therefore, the work holder 150 does not function when measuring the unbalance of the work.

In the above embodiment, an example in which the work holder 150 is incorporated in the holding device of the measuring station 1 has been described.

However, a pre-processing station for performing pre-processing on the workpiece before the work unbalance is measured at the measuring station 1 may be provided. The pretreatment station has a configuration similar to that described with reference to FIG. 13, but has a seating surface ( A holding device provided with 14 1) may be arranged, and the workpiece W may be held and strongly pressed by the workpiece presser (15) so that a large seating mark may be formed on the surface of the workpiece. The workpiece with a large seating mark is then sent to measuring station 1 and processing station 2 in sequence.

For example, the seating surface 14 1 of the holding device at the measuring station is convexly curved with respect to the surface of the workpiece W: a curved surface that is curved in the surface direction (for example, in the axial direction of the workpiece W (perpendicular to the paper surface in FIG. 13)). In the case of), if the seating surface (141) of the holding device in the pretreatment station is a flat surface, a large seating mark can be formed in the pretreatment station. Further, if the seating surface (141) of the holding device of the pretreatment station is a concave curved surface substantially along the surface of the work W, the larger A seating mark can be made on the surface of the work W.

The present invention is not limited to the embodiments described above, and various changes can be made within the scope of the claims.

For example, in the above embodiment, the clamp claws 14 2 in the measuring station 1 are illustrated as hardened flat claws, but the clamp claws 14 2 are not set as flat claws, and the clamp claws provided on the As in the case of 224, a clamp claw that makes point contact with the workpiece W or linearly contacts the workpiece W in the axial direction may be used. The crump of such shape. By using the claws, a clamp force required for measurement can be generated with a smaller clamping force.

This application claims the priority of the treaty based on Japanese Patent Application No. 2000-2004-0777 filed with the Japan Patent Office by July 5, 2000. The entire disclosure of the application shall be incorporated into this application.

Claims

The scope of the claims

1. It has a measuring station for measuring the unbalance of a workpiece rotating about an axis, and a processing station for drilling at least a hole for a stroke based on the measurement result. The processing station is a mass centering machine equipped with a holding device for holding the work,

A mass centering machine, wherein the holding device includes a clamp claw that makes point contact with a workpiece.

2. The holding device includes a pair of seating surfaces for receiving the work from obliquely below left and right when the work is viewed in the 轴 direction,

Claims: A pair of clamp claws that oppose a seating surface with a workpiece interposed therebetween, and that, when viewed in the axial direction of the workpiece, make point contact with the surface of the workpiece obliquely from above and to the left and right to hold down the workpiece. The mass centering machine described in 1.

3. The mass centering machine according to claim 2, wherein the holding device has a drive source for driving a pair of clamp claws.

4. The crump. The claw has a shape that makes point contact with the surface of the work when viewed in the axial direction of the work, and has a shape that makes linear contact with the surface of the work when viewed in a direction perpendicular to the axial direction of the work. The mass centering machine described in 2.

5. The massaging ring machine according to claim 4, wherein the clam claw has a downwardly convex shape when viewed in a direction orthogonal to the axial direction of the workpiece.

6. The crump. 5. The mass centering device according to claim 4, wherein the claw has a rectangular shape and protrudes downward when viewed in a direction perpendicular to the axial direction of the workpiece.

7. The mass centering machine according to claim 1, wherein the clam claw protrudes downward in an inverted triangular pyramid shape and has a pointed lower end.

8. With a mass-sensing ring machine that has a measuring station for measuring the unbalance of the work rotating around the axis and a work station for drilling at least a center hole on the work based on the measurement results. So,

Perform pre-processing on the workpiece before measuring the unbalance at the measurement station. Equipped with a pre-processing station for

The pretreatment station is provided with a pair of holding devices for holding the work, and each holding device includes a pair of seating surfaces and a pair of clamps for seating the work,

Each of the pair of seating surfaces can receive a workpiece from obliquely below, and a pair of clamps are provided opposite to the pair of seating surfaces to press the workpiece received by the pair of seating surfaces against the seating surface. As shown in the figure, the work is pressed from the opposite side of the received part.

Further, a mass is provided which presses the work from above to below so that the work surface received by the pair of seating surfaces is marked on the surface of the work that comes into contact with the seating surface. Centering machine.

9. The mass centering device according to claim 8, wherein the pre-processing station is incorporated in the measuring station.