JP5311023B2 - Heart compensation function addition device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily add a core compensating function to a chuck 10 which does not have the core compensating function. <P>SOLUTION: A device 20 for adding the core compensating function is concentrically detachably fixed to a front surface of a main chuck 10 fixed to a spindle of a lathe. Each grasping pawl 30 of the device 20 is integrated with a piston 31 in a cylinder 26, and each cylinder is communicated through a closed circuit 27 of pressurized fluid. Pistons 28 of drive cylinders 25 provided for the closed circuits are pressed by forward/backward movement of the grasping pawls 6 of the main chuck. When a draw bar 1 is retreated, the grasping pawls 6 push the pistons 28, pressurized fluid a in the cylinders 25 is fed to cylinders for the forward/backward movement through communication holes 27, and the grasping pawls 30 move forward to an axis o of a body 21 to grasp the workpiece W. At this time, the cylinder of each grasping pawl is communicated through the closed circuit 27 of the pressurized fluid, so that each grasping pawl grasps the workpiece by uniform force. Namely the core compensating function is exhibited. When the device for adding the core compensating function is removed, the main chuck carries out ordinary chucking action. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  This invention is detachably fixed to the front surface of the main chuck fixed to the main spindle of the lathe, and the gripping claws are gripped with an equal force following the inner periphery or outer periphery of the workpiece with reference to both centers and boss holes. The present invention relates to a device for adding a heart compensation function for providing a heart-compensating chuck, which adds a heart compensation function to the main chuck when the main chuck does not have the heart compensation function.

There are two types of chucks, which are fixed to the main spindle of this type of lathe, to grasp the workpiece. There are a centripetal type with the gripping part as a concentric reference and the above-mentioned center compensation type, and the former is a general grasping type. However, the heart compensation type is also in demand.
For this reason, a center-compensated chuck is prepared, and when necessary, a centripetal chuck is replaced with a center-compensated chuck, or a lathe with a center-compensated chuck is installed separately from a lathe with a centripetal chuck. I have prepared.
Some chucks have a centripetal function and a center compensation function (see Patent Document 1, Claims, and FIG. 1).

JP 2006-102858 A

The chuck having the centripetal function and the cardiac compensation function is effective as it is, but the structure is complicated and the cost is high.
Under today's demand for cost reduction, it is desired that a chuck without a heart compensation function can be easily added.

  In view of the above situation, an object of the present invention is to easily add a heart compensation function to a chuck having no heart compensation function.

In order to achieve the above object, according to the present invention, a device having a heart compensation function can be detachably attached to a chuck having no heart compensation function.
In this way, when the heart compensation function is not necessary, if the device of the heart compensation function is removed, the work can always be grasped by the function of the chuck attached to the spindle. On the other hand, if a heart compensation function is necessary, it is possible to work by grasping the workpiece with the heart compensation function by attaching a device having the heart compensation function to an existing chuck.

  As a configuration of the present invention, it is a device for adding a center compensation function that is detachably fixed to the front surface of a main chuck fixed to a main shaft of a lathe, and the main chuck has a pusher that can advance and retreat on the front surface thereof. The heart compensation function adding device has a plurality of gripping claws for grasping a workpiece by moving back and forth from the outer peripheral surface to the outer side or from the inner peripheral surface to the inner side on the outer peripheral surface or inner peripheral surface of the annular main body. Each gripping claw is integrated with a piston in each cylinder in the heart compensation function adding device, and each cylinder is communicated with a pressure fluid closed circuit. A drive cylinder that pressurizes and depressurizes by advancing and retreating is interposed, and a piston in the drive cylinder can be pressed by advancing and retreating the pressing element of the main chuck.

When the heart compensation function adding device having this configuration is fixed to the front surface of the main chuck, the driving cylinder is operated by the advancement / retraction of the pressing member of the main chuck to pressurize and depressurize the pressure fluid closed circuit. The pressure fluid pressure in the cylinder of each gripping claw is also pressurized and depressurized, and the piston in that cylinder moves forward and backward, and with that advancement, the gripping claw integrated with the piston also moves forward and backward, so that both centers and boss holes etc. Hold or release the workpiece.
At this time, the operating cylinders of the gripping claws are communicated with each other by a pressure fluid closed circuit, and each gripping claw presses the work with an equal force, and exhibits a heart compensation function to grasp the work. Also, when grasping the workpiece by the inward movement of the gripping claw, the outer diameter is grasped, and when grasping the workpiece by the outward movement, the inner diameter is grasped. In the former case, the gripping claw is placed on the inner peripheral surface of the annular body. In the latter case, the gripping claw is provided on the outer peripheral surface of the annular main body (having the gripping claw on the outer peripheral surface of the annular main body).

  Various means can be used to attach the heart compensation function adding device having this configuration to the main chuck, for example, bolting, magnet chucking, or the like. At this time, as long as this heart compensation function adding device can be operated by the presser of the main chuck, this heart compensation function adding device can be fixed to the main chuck in the same center or fixed eccentrically, When the gripping claws 30 are operated by the gripping claws 6 as in the embodiment described later, for example, when the gripping claws 30 are operated at the same center, the operation can be performed smoothly. .

  If the pressing member of the main chuck is an existing gripping claw, the main chuck can perform normal chucking with the gripping claw. As an example of a configuration employing the existing gripping claw, the main chuck is a swinging retractable chuck, and the swinging retractable chuck is an actuator that moves back and forth with a draw bar that moves back and forth on the central axis in the chuck body. In addition to providing a flange, a plurality of jaw actuators connected to the actuator flange are provided at the front of the chuck body, and each jaw actuator swings in the radial direction of the main chuck as the actuator flange moves forward and backward together with the draw bar. The workpiece can be grasped by a gripping claw provided on the jaw actuator, and the gripping claw can be the presser.

The number of gripping claws of the heart compensation function adding device can be determined as long as there are two or more gripping claws, and the number of gripping claws can be determined appropriately. For example, it corresponds to the number of gripping claws of a conventional chuck. If the total sum of the vector amounts of the acting force of the gripping claws on the workpiece below is zero and the balance is satisfied, the number is arbitrary.
In other words, the center compensation function, when grasping a workpiece set with both centers and boss holes as a reference with each gripping claw, the total vector amount of the acting force of each gripping claw on the workpiece becomes zero. It is balanced and fixed without moving the workpiece. For this reason, each gripping claw is arranged around the annular body so that the sum of the vector amounts of the acting force on the workpiece becomes zero and balances.
Therefore, the gripping claws of the heart compensation function adding device may be arranged in the same manner as the gripping claws of the conventional heart compensation type (competitive) chuck, and the gripping shape of the workpiece (the gripping point of each gripping claw on the workpiece is tied) Various envelopes), for example, a circular shape, an elliptical shape, a polygonal shape such as a square, a partially cutout shape, and the like.

For example, when the workpiece has a circular cross section and the same polygon, the gripping claw has a circular shape (holding shape). If the workpiece W is a cylindrical body, for example, as shown in FIG. When the workpiece W is grasped by the gripping claws, the vector of the acting force (a, b, c) of each gripping claw on the workpiece W is assumed to be the same magnitude toward the reference point o by the center boss hole or the like. The sum is zero (vector (a + b + c) = 0), and the above condition can be satisfied.
When there are four or more gripping claws that are multiples of 2, the two centering points are located at the same circumferential equal position, and the same circumferential distance from the equal position is equal to the left and right equidistant distances. One gripping claw can be provided to satisfy the above condition. For example, as shown in FIG. 5, a total of six pieces are provided at one equidistant (a, b, c, d, e, f) on the same circumference from the three equally divided positions s around the workpiece W of the cylinder. (Vector (a + b + c + d + e + f) = 0). At this time, the circumference of the equally divided position s and the envelope circumference of the gripping point of the gripping claw can be different circles of the same center, and each gripping claw can be an axis of the annular body (center hole center). o) Able to move forward and backward in the radial direction.

On the other hand, when the grasping shape of the workpiece is irregular with respect to the center line (the reference line) (not the X axis and Y axis in the central axis), for example, a crankshaft, a cam, or an aluminum precision cast product There are several holes in the case, and when processing based on the two places, the spacer is interposed between the workpiece and the gripping claw so that the center line of the grasping shape becomes a circle centered on the reference line o. For example, as shown in FIG. 6, the position and size of the gripping force of the gripping claw (the acting force is directed toward the center o of the boss hole) on the deformed workpiece W are changed, and the sum of the vector amounts is changed. Or zero (vector (a + b + c + d + e) = 0). At this time, the case where the boss hole reference o and the center line of the main chuck coincide with each other can be considered. The illustrated boss hole reference o is eccentric to the right from the center of the main chuck, and a work block is prevented from moving by providing a guide block or the like on the left upper and lower side surfaces. Note that the magnitude of the acting force is changed by adjusting the pressure receiving area of the piston, for example, when the gripping claw is operated by the advancement / retraction of the piston.
In addition, if the grasping shape is an ellipse and the envelope of the gripping point is not circular, but is symmetric with respect to both the XY axes, the gripping claws that advance and retreat in the XY axis direction (X-axis direction or Y-axis) 2 in the axial direction or 4 in both axial directions), or multiple gripping claws that are multiples of 2 of 4 or more, and two as a set, the center line of which is the X-axis direction (4 gripping claws) or The arrangement is such that it is in the Y-axis direction (4 pieces) or in both axial directions (8 pieces). At this time, each gripping claw is advanced and retracted toward the center of the ellipse (the reference line o).
In this way, any number of gripping claws can be provided at any position depending on the gripping shape of the workpiece, but it is calculated appropriately so that the sum of the vector amounts of the acting force of the gripping nails on the workpiece becomes zero. And decide.

  Although the number of drive cylinders provided in the pressure fluid closed circuit may be one, it is preferable to match the number of the pressing elements. For example, assume three. In the case of a plurality, the plurality of drive cylinders can be provided at the same circumferential equal position around the axis of the center compensation function adding device (annular body). At this time, the annular main body and the main shaft can be the same axis, and the pressing element can be a gripping claw of the main chuck.

The pressure fluid may be hydraulic fluid used in this type of lathe, but when used for a long period of time, the pressure fluid may be removed due to wear / cutting of the O-ring or loosening of the fastening screw provided in the device for adding the core compensation function. If it leaks, the pressure fluid in the closed circuit will decrease, and the initial grasping minimum diameter will increase or malfunction will occur. At this time, if the outflow speed of the pressure fluid is high, the problem occurs instantaneously. Therefore, if the pressure fluid leaks, use a high-viscosity fluid that has a low outflow speed and is unlikely to cause such a problem immediately. It is better to make it difficult to leak. For example, it does not cause rust and corrosion of high-viscosity hydraulic oil, low-viscosity grease, or a mixture of normal hydraulic oil and grease compared to normal hydraulic oil used for lathes, and deteriorates the O-ring. Although it is preferable to use a material that is difficult and easily available, slime or the like may be used.
When the viscosity of the pressure fluid is too high, it is difficult to fill the closed circuit or the like, and an air pool is generated in the filling fluid, and the operating force may not be smoothly transmitted to the gripping claws. For this reason, the viscosity is appropriately set by experiments or the like so that the fear does not occur. For example, the viscosity is about the viscosity of cream soup.

  In addition, if the pressure fluid leaks, it is preferable that the leak can be found quickly. Normal hydraulic fluid is a light yellowish transparent color, and the hydraulic fluid adheres around the chuck. It is difficult to distinguish from leaks. For this reason, in order to facilitate the detection of the leakage, it is preferable that the pressure fluid is colored so that it can be clearly distinguished from the hydraulic oil. For coloring, for example, powder or liquid such as vermilion, blue ink, black ink (carbon), etc. is mixed into the pressure fluid to make it a dark color that is easy to find, or a commercially available colored hydraulic oil or colored grease is used. To do.

  Since the present invention is configured as described above, the center compensation function can be easily added to a chuck that does not have a center compensation function. Can have a function.

Cut front view of one embodiment of the present invention Cut right side view of the same embodiment The perspective view which removed the cardiac compensation function addition apparatus of the embodiment Illustration of one action of workpiece gripping force Other action explanatory drawing of work gripping force Still another action explanatory diagram of work gripping force

  FIG. 1 to FIG. 3 show an embodiment, and this embodiment is a swing-in type chuck. As shown in FIG. 1, the central axis (axial center) o of the chuck main body which is the main chuck 10 of the present invention. The drawbar 1 positioned above can be moved back and forth in the axial direction, and a support drawbar 3 is connected to the concentric shaft via a fixing bolt 2 in front of the drawbar 1, and the drawbar 1 and the support drawbar 3 are It is designed to move forward and backward.

  An actuator flange 4 is integrally provided on the support draw bar 3, and a jaw actuator 5 is connected to the circumference of the actuator flange 4 at three equal intervals (at intervals of 120 degrees). The connection between the jaw actuator 5 and the actuator flange 4 is configured by a spherical portion 5a, a spherical bearing portion 5b and the like (refer to Patent Document 1 for details) as in the prior art. 5 swings (in the radial direction) toward the center (axial center) o of the chuck body.

  A grip claw 6 is attached to each jaw actuator 5 with a bolt, and the draw bar 1 is retracted (pulled leftward in FIG. 1) to advance the grip claw 6 toward the central axis o, thereby moving the workpiece W. To figure out. That is, the work is grasped by the centripetal function. The gripping claw 6 employs an appropriate shape depending on the gripping shape of the workpiece.

  The present invention is characterized in that the heart compensation function adding device 20 can be detachably attached to the chuck 10 having the above-described configuration. The heart compensation function adding device 20 penetrates the annular body 21 through the bolt 22. Then, it is fastened (attached) to the chuck 10 concentrically by being screwed into the front surface of the main body of the chuck 10 via the cylindrical sleeve 23. The bolts 22 are provided at the same circumferentially equal position of the main body 21, but the number is arbitrary as long as it is two or more.

  The core compensation function adding device main body 21 is provided on the inner and outer surfaces in a divide-by-three manner between the drive cylinder 25 and the drive cylinder 25 that opens only on the outer surface at the same circumferential three-divided position around the axis o. Opening and retracting gripping claw advance and retreat (actuation) cylinders 26 are formed, and the cylinders 25 and 26 are filled with a pressure fluid a colored in a color different from that of the lathe hydraulic oil, and are respectively connected to the communication holes 27. It becomes a closed circuit that is in communication, and a uniform fluid pressure is applied. The filling and replenishment of the pressure fluid a is not shown, but a supply port with a closing plug is provided on the outer peripheral portion of the apparatus main body 21 and the supply port is brought up (positioned) to the air. Do it while escaping.

The drive cylinder 25 is fitted with a piston 28 through an O-ring 28 a so that the piston 28 can move forward and backward. When the piston 28 is pushed (moves toward the center o), the pressure fluid a in the cylinder 25 passes through the communication hole 27. To the advance / retreat cylinder 26. At this time, the size (pressure receiving surface) of each piston 25 is the same.
The opening / retraction cylinder 26 is liquid-tightly sealed with a stopper 29 on its outer surface side, and a piston 31 integral with a gripping claw (joo) 30 is fitted through an O-ring 31a so as to freely advance and retract. The gripping claws 30 protrude from the inner peripheral surface of the main body 21, and when the pressure fluid a is fed into the cylinder 26 from the drive cylinder 25, the gripping claws 30 advance toward the axis o of the main body 21. At this time, similarly, the size (pressure receiving surface) of each piston 31 is the same.

  The heart compensation function adding device 20 is configured as described above. As shown in FIGS. 1 and 2, the front surface of the chuck main body of the main chuck 10 when the gripping claws 6 of the main chuck 10 are in the released state (the outermost position). After the fixing center 8 is attached to the main chuck 10 with the bolt 22 and fastened with the bolt 22, the outer surface of the piston 28 of the drive cylinder 25 of the heart compensation function adding device 20 is located inside the gripping claw 6 of the main chuck 10. Abut or close. The fixed center 8 may be left attached to the main chuck body as long as it does not interfere with the workpiece grasping by the centripetal function of the main chuck 20 described above.

In this state, as shown in FIG. 1 and FIG. 2, the cylindrical work W based on both centers is positioned on the central axis of the fixed center 8 (the central axis o of the main chuck 10), and the front end portion is omitted from illustration. After the center hole is pressed and fixed with the tailstock, when the draw bar 1 is retracted, the gripping claw 6 advances toward the central axis o and pushes the piston 28. When the piston 28 is pushed, the pressure fluid a in the cylinder 25 is sent to the advance / retreat cylinder 26 through the communication hole 27 and the gripping claws 30 advance toward the axis of the main body 21 to grip the workpiece W. .
At this time, since the cylinder 26 of each gripping claw 30 is communicated with the closed circuit 27, each gripping claw 30 grips the workpiece W with a center compensation function using an equal force.

  If the workpiece W is processed with the center compensation function and is processed, and the processing is completed, the drawbar 1 is advanced, the gripping claws 6 are retracted, and the pressing force to the piston 28 is released. By this release, the workpiece W can be removed from the gripping claw 30 of the heart compensation function adding device 20. At this time, if a compression coil spring is loaded in the portion s (see FIG. 1) in the advance / retreat cylinder 26, the gripping pawl 30 can be moved back into the cylinder 26 by the spring as the pressing force is released. This makes it easy to remove the workpiece W.

  In this embodiment, the workpiece W is a cylindrical center-shaped shaft having a cylindrical shape, the grasping shape is a circle centering on both center central axes o, and the axis of the annular main body 21 and the main chuck 10 (main shaft) is Since the gripping claws 30 are arranged so that the sum of the vector amounts of the acting force on the workpiece W is zero with respect to the axis o, the workpiece W is not subjected to surface processing. Even if the center hole is slightly decentered with respect to the center of the grasping shape (circular shape) by the gripping claws 30 as in the case of the above, the eccentricity is small, and the amount of advancement and retraction of each gripping claws 30 is automatically adjusted, so There is no misalignment caused by elastically deforming the workpiece W by the holding force or by slightly bending the fixing center 8.

  In the above embodiment, the gripping claw 30 is protruded from the inner peripheral surface of the main body 21 of the heart compensation function adding device 20, but the positions of the plug 29 and the gripping claw 30 are reversed. If the gripping claws 30 protrude from the outer peripheral surface of the main body 21, the inner diameter grasping type can be obtained. In this case, the main chuck 10 may be the outer diameter grasping type of the above-described embodiment as long as there is no problem in grasping the inner diameter by the gripping claws 30. It can be set as the aspect protruded to the inner peripheral surface of 21.

  Further, the main chuck 10 is not limited to the swinging type by the jaw actuator 5 of the embodiment, and if the gripping claw such as a wedge-shaped power chuck can be moved back and forth toward the center, the center compensation function adding device 20 is used. For example, the present invention can be applied to a scroll chuck as long as it can be attached. In the case of the swing type or wedge-shaped power chuck of the embodiment, in particular, in the case of the wedge-type power chuck, the rigidity of the chuck is high, so that the operation of the center compensation function adding device 20 can be reliably ensured.

The advancement / retraction of the gripping claws 30 of the heart compensation function adding device 20 by the main chuck 10 is not limited to the gripping claws 6 of the main chuck 10, but may be any one that can push the piston 28. For example, a dedicated presser may be provided on the main chuck 10. Further, the pressing element may be a manual one.
As the pressing element, it is possible to adopt a pressing element that advances and retreats from the inside of the chuck body to the outside as in the above-described inner diameter grasping type. In this case, similarly, the drive cylinder 25 of the heart compensation function adding device 20 is preferably configured such that the piston 28 protrudes from the inner peripheral surface of the main body 21.

  Thus, it should be considered that the embodiments disclosed herein are illustrative and non-restrictive in every respect, and the scope of the present invention is not limited to the above meaning, but is defined by the claims. And all modifications within the meaning and scope equivalent to the terms of the claims are intended to be included.

1 Drawbar 4 Actuator Flange 5 Jaw Actuator 6 Grip Claw (Presser)
8 Fixed Center 10 Main Chuck 20 Center Compensation Function Adding Device 21 Center Compensation Function Adding Device Main Body 22 Center Compensation Function Adding Device Mounting Bolt 25 Drive Cylinder 26 Grasping Claw Advance Cylinder 27 Cylinder Communication Hole (Pressure Fluid Closed Circuit)
28 Piston 30 of drive cylinder Gripping claw 31 of the center compensation function addition device Piston W of the cylinder for gripping claw advancement Double center reference work a Pressure fluid o Center axis of main shaft (axial center of annular main body)

Claims (5)

A center compensation function adding device (20) detachably fixed to the front surface of a main chuck (10) fixed to a main spindle of a lathe,
The main chuck (10) has a pusher that can be advanced and retracted on the front surface thereof, and the center compensation function adding device (20) is arranged on the outer peripheral surface or inner peripheral surface of the annular body (21) from the outer peripheral surface to the outer side. Or a plurality of gripping claws (30) for grasping the workpiece (W) by moving back and forth from the inner peripheral surface toward the inner side,
Each gripping claw (30) is integrated with a piston (31) in each cylinder (26) in the heart compensation function adding device (20), and each cylinder (26) communicates with a pressure fluid closed circuit. The pressure fluid closed circuit is provided with a drive cylinder (25) that pressurizes and depressurizes as the piston (28) advances and retreats, and the piston (28) in the drive cylinder (25) is connected to the main chuck ( 10) A device for adding a heart compensation function, wherein the device can be pressed by advancing and retreating the pressing element.   The plurality of gripping claws (30) can be moved forward and backward in the radial direction from the axial center (o) of the annular body (21) at the same circumferentially equal position on the outer circumferential surface or inner circumferential surface of the annular body (21). The heart compensation function adding device according to claim 1, which is provided.   When there are four or more multiples of 2 above gripping claws (30), the center point of the two claws (30) is set to the same circumferential equal position, and the left and right equal distances on the same circumference from the equal position. A gripping claw (30) is provided on each of the plurality of gripping claws (30), and each gripping claw (30) is provided so as to be movable forward and backward in a radial direction from the axis (o) of the annular body (21). 2. A device for adding a cardiac compensation function according to 1.   The heart pressure compensation function adding device according to any one of claims 1 to 3, wherein the pressure fluid (a) is colored.   5. The addition of a heart compensation function according to claim 1, wherein the pressure fluid (a) is a high-viscosity hydraulic oil, a low-viscosity grease, or a mixture of hydraulic oil and grease. apparatus.

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