KR100392415B1 - Chuck with position detecting function - Google Patents

Abstract

A drive unit 4 having a plurality of opening and closing jaw members 3 and 3 for holding a workpiece in the casing 2, a drive rod 9 for linear reciprocating motion, and a straight line of the drive rod 9 A converter mechanism 7 for converting the reciprocating motion into opening and closing operations of the jaw members 3 and 3, a scale 33 shifting in synchronization with the driving rod 9, and a reader for reading the scale on the scale 33 And a linear guide mechanism (6) for guiding the linear reciprocating motion of the scale (33), the position detecting portion (5) capable of detecting the operating position of the jaw members (3, 3) with respect to the entire stroke. Assemble

Description

CHUCK WITH POSITION DETECTING FUNCTION}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chuck that grips a workpiece between a plurality of opening and closing jaw members and conveys the workpiece to a desired place, and more particularly, to a chuck having a position detection function capable of detecting an operating position of the jaw member.

It is well known in the art that an air cylinder using air pressure, a linear motor using electromagnetic force, or the like is incorporated as a driving source, and a plurality of jaw members are opened and held to hold a workpiece by the action of these air cylinders or linear motors.

Some chucks of this kind are provided with a position detecting device using magnetism to detect the open / close position of the jaw member. The position detecting device is constituted by a permanent magnet attached to the drive rod of the air cylinder or linear motor, or attached to the jaw member, and a magnetic sensor attached to the casing side. It is to detect the open / close position of.

However, since the conventional position detecting device detects permanent magnets attached to the drive rod or the jaw member, the position at the end of the opening / closing stroke of the jaw member, that is, the position at which the jaw member grasps the work or the opening Only the position could be detected, and the operation position of the jaw member could not be detected for the entire stroke.

The main technical problem of the present invention is to provide a chuck having a position detection function capable of detecting the operating position of the jaw member with respect to the entire stroke.

Another technical problem of the present invention is to provide a chuck of a rational design structure in which the driving unit for opening and closing the jaw member and the position detecting section for detecting the operation position of the jaw member together with other mechanisms are efficiently assembled in the casing so as not to be enlarged. Is in.

Another technical problem of the present invention is to provide a stable opening and closing operation by preventing the opening and closing operation of the jaw member from being smoothly performed by organically combining the driving unit and the position detecting unit in the casing in the chuck. .

1 is a longitudinal sectional front view showing a first embodiment of a chuck according to the present invention.

FIG. 2 is a longitudinal plan view of the chuck of FIG. 1. FIG.

3 is a side cross-sectional view of the main part of the chuck of FIG.

4 is a longitudinal sectional front view of the second embodiment of the chuck according to the present invention;

(Explanation of the sign)

1A... Chuck 2... Casing

3, 3... . Driving part

5... Position detecting unit 6. Linear guide mechanism

7... Converter port 9.. Driving rod

In order to solve the above problems, according to the present invention, a plurality of jaw members for gripping the workpiece is provided to be opened and closed in the direction crossing the axis line of the casing in the axial end of the casing; A driving part having a driving rod for linear reciprocating motion in a direction parallel to the axis of the casing, the driving part being provided at a portion on the axial base end side of the casing on one of the left and right half sides of the casing; A scale for linearly reciprocating in a direction parallel to the axis of the casing in synchronism with the drive rod, and a reader fixed at a predetermined position on the casing to read the scale engraved on the scale, A position detecting unit installed at a position adjacent to the driving unit and capable of detecting an operating position of the jaw member with respect to the entire stroke; A linear guide mechanism installed between the driving unit and the position detecting unit to guide linear reciprocating movement of the scale; And a converter mechanism installed between the jaw member and the drive unit to convert the linear reciprocating motion of the drive rod into the opening / closing motion of the jaw member.

In the chuck having the above-described configuration, the jaw member is opened and closed by the movement of the drive rod of the drive unit, and the workpiece is gripped or released. At this time, the scale on the scale moving in synchronization with the drive rod is continuously read by the reader, whereby the operating position of the jaw member is detected for the entire opening and closing stroke.

Here, the drive unit, the position detecting unit and the linear guide mechanism are efficiently assembled so as to be accommodated within the width of the casing, that is, the installation area of the jaw member, at a position adjacent to the casing. The chuck does not increase in size. In addition, by providing the linear guide mechanism between the drive unit and the position detection unit, not only can the scale be stably shifted in synchronization with the drive rod, but also the movement of the drive rod can be reliably transmitted to the jaw member through the transducer mechanism. The jaw member can be opened and closed stably.

According to a specific embodiment of the present invention, the converter mechanism includes two levers for opening and closing the jaw member by swinging, and a relay plate for connecting these levers to the drive rod, wherein the relay plate has a central image of the chuck. The relay shaft is located in the pivot shaft, and the base end of each lever is pivoted on the relay shaft so as to be rotatable with a common support shaft. The relay plate includes a scale supporting member for supporting the driving rod and the scale. The relay shafts are connected to be shifted together through the relay plates at different positions with the relay shafts interposed therebetween.

According to another specific embodiment of the present invention, the linear guide mechanism includes a guide rail and a slider slidable along the guide rail, the guide rail is fixed to the outer wall of the drive unit in parallel with the drive rod, and the slider is on the scale side. Is attached to.

When connecting the drive rod to the relay plate, it is preferable to have a degree of freedom in the inclined direction between them by floating collar by inserting a collar (collar) in order to prevent distortion.

According to one embodiment of the present invention, the drive section includes a linear motor operated by an electromagnetic force, and the linear motor is configured to advance the drive rod forward and backward.

The linear motor includes a cylindrical magnetic frame made of a magnetic body, a non-magnetic bobbin accommodated in the magnetic frame, a plurality of magnetic coils wound on the bobbin, and slidably inserted in the bobbin in an axial direction. And a piston assembly connected to the piston assembly, wherein the piston assembly is formed by attaching a plurality of permanent magnets having a round annular shape to an outer circumference of the drive rod by sandwiching yokes therebetween.

According to another embodiment of the present invention, the drive section includes a fluid pressure cylinder mechanism that operates by fluid pressure, and is configured to advance the drive rod forward and backward by the fluid pressure cylinder mechanism.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred exemplary embodiment of a chuck with position detection function according to the present invention will be described in detail below with reference to the drawings.

1 to 3 show a first embodiment of the present invention, wherein the chuck 1A of the first embodiment uses a linear motor using electromagnetic force as a driving source for opening and closing the jaw members 3 and 3. In more detail, the chuck 1A includes a casing 2 formed in a foot shape as a whole, and a plurality of jaw members 3 for holding a workpiece, which are provided to be opened and closed at an axial end of the casing 2. 3) and a drive section 4 provided on one of the left and right halves of the base end side of the casing 2 and having a drive rod 9 for linear reciprocating motion in the axial direction of the casing 2; And a position detecting unit 5 provided at a position adjacent to the driving unit 4 so as to detect the operating position of the jaw members 3 and 3 with respect to the entire stroke, and the driving unit 4 and the position detecting unit ( 5) between the linear guide mechanism 6 provided between the jaw members 3 and 3 and the drive unit 4, and the linear reciprocating motion of the drive rod 9 is opened and closed. It has a converter mechanism (7) to convert to.

The casing 2 is composed of a first member 2a having a rectangular plate shape, and a second circumferential second member 2b attached to the first member 2a, and the first member 2a. The two jaw members (3, 3) are supported to open and close in a direction orthogonal to the axis of the casing (2), and the drive section (4), the position detection section (5) and the linear guide on the second member (2b) The mechanism 6 is installed side by side.

The drive part 4 has a cylinder part 10 formed as a part of the casing 2, and the linear motor 8 is accommodated in this cylinder part 10. As shown in FIG. The linear motor 8 includes a cylindrical magnetic frame 12 made of a magnetic material, a bobbin 13 made of a nonmagnetic material accommodated in the magnetic frame 12, and a plurality of magnetic coils 14 wound on the bobbin 13. And a piston assembly 15 slidably inserted in the bobbin 13 in the axial direction. The piston assembly 15 attaches a plurality of round annular permanent magnets 15a with a yoke 15b interposed therebetween on an outer circumference of the drive rod 9 that slidably penetrates the center portion of the cylinder portion 10. It is formed by. These permanent magnets 15a are provided with the north pole and the south pole on both sides in the axial direction, and are arranged in such a state that these magnets are alternately reversed. In other words, the N poles and the S poles of adjacent magnets 15a and 15a are arranged to face each other, and are fixed to a predetermined position on the drive rod 9 by the pressing plate 15c.

In the drawing, reference numeral 16 denotes a piston cover attached to one end of the tube part 10, and 17 denotes a cap attached to an outer side thereof, and an end of the driving rod 9 is slidably supported by the piston cover 16. have.

Therefore, in the drive unit 4, when the direct current or the reverse DC current is applied to the magnetic coil 14 through the lead wire 14a, the piston assembly 15 is moved forward or backward in accordance with the direction of the current, the drive rod (9) also move back and forth.

The tip of the drive rod 9 is connected to a substantially L-shaped relay plate 20 in plan view of a part of the transducer tool 7, and the main component of the transducer tool 7 is connected to the relay plate 20. Two levers 21 and 21 which are members are connected. These levers 21 and 21 are arranged symmetrically in the space portion between the first member 2a and the second member 2b of the casing 2, and the middle portion of each lever 21 is the shaft 22. It is pivotably pivoted in the casing 2 by the. In addition, the proximal end of each lever 21 is pivotably pivoted to a support shaft 23 common to the relay shaft 20a extending from the relay plate 20 to be located at the center of the chuck. The tip of 21 is fitted in the hole 24 of the second member 2b and is connected to the two jaw members 3 and 3 individually.

The jaw members 3 and 3 are formed of a first portion 3a having a recess 26 at an upper surface center thereof, and a second portion 3b protruding in a T or L shape from the first portion 3a. As shown in FIG. 3, the first portion 3a is slidably fitted into the guide groove 27 formed on the front surface of the second member 2b, thereby following the guide groove 27. It is supported to open and close linearly. In addition, a plurality of spherical or rolled armatures 28 are fitted in the sliding grooves formed on the outer surface of the first portion 3a and the inner surface of the guide groove 27 facing each other. By 28, the opening and closing of the nail members 3 and 3 are performed smoothly. As a result, the guide groove 27 and the first portion 3a of the jaw members 3 and 3 constitute a linear guide mechanism for linearly guiding opening and closing of the two jaw members 3 and 3.

In addition, the relay plate 20 is connected to the drive rod 9 by a bolt 30 at a position different from the relay shaft 20a, and together by the expansion and contraction of the drive rod 9. It is designed to move forward or backward. Then, the levers 21 and 21 swing around the shaft 22 by the forward and backward movement of the relay plate 20, and the pair of jaw members 3 and 3 open and close to hold the workpiece therebetween. Or to be liberated. In practice, attachments fitted to the workpiece are attached using the attachment holes 3c provided in the jaw members 3 and 3, and the workpiece is gripped by the attachment.

In addition, when connecting the drive rod 9 to the relay plate 20, in order to prevent the distortion caused by the inclination, by inserting the collar 31 between them in a floating manner, a slight degree of freedom in the inclination direction It is desirable to have a.

The position detecting unit 5 is a plate-shaped glass scale 33 engraved with a plurality of linear scales at a constant pitch on the surface, and an encoder reader for reading the number of scales on the scale 33 and outputting a read signal ( 34). The scale 33 is attached to the scale supporting member 38, and the scale supporting member 38 is substantially opposite to the relay plate 20 with the relay shaft 20a interposed with the drive rod 9. It is fixed by the bolt 39 in the other position of, and one reader 34 is fixed in the fixed position on the casing 2. As shown in FIG.

In the position detecting unit 5, a waveform forming machine 35 for shaping and converting the signal waveform output from the reader 34 into a digital signal and outputting it toward a controller (not shown) is provided on the outer wall of the driving unit 4. The fixed attachment member 36 is attached so as not to be pushed out of the casing 2 in a position adjacent to the reader 34.

Then, the scale number on the scale 33, which is linearly reciprocated in synchronism with the drive rod 9, is read by the reader 34, and the signal waveform is shaped by the waveform molding machine 35 and sent to the controller. By arithmetic processing by the controller, the operating position of the drive rod 9, that is, the operating positions of the jaw members 3 and 3, is detected.

In addition, since the detection principle of such an encoder-type detection device is already known, further detailed description thereof will be omitted.

The linear guide mechanism 6 provided between the position detection unit 5 and the drive unit 4 is composed of a guide rail 6a and a slider 6b slidable along the guide rail 6a. The guide rail 6a is attached to the outer wall of the drive unit 4 in parallel with the drive rod 9, and the slider 6b is attached to the scale support member 38. Thus, by providing the linear guide mechanism 6 between the position detection part 5 and the drive part 4, even if the drive rod 9 is connected to the relay plate 20 in the position different from the relay axis 20a in the shaft center 20a. The drive rod 9 allows the scale 33 and the pair of levers 21 and 21 to be smoothly and reliably operated through the relay plate 20 without any distortion.

In this way, the drive part 4, the position detection part 5, and the linear guide mechanism 6 are accommodated in the installation areas of the jaw members 3 and 3 at mutually adjacent positions in the casing 2, and are pushed to the side. It is assembled not to come out.

In the chuck having the above-described configuration, the jaw members 3 and 3 are opened and closed by the movement of the drive rod 9 of the drive section 4, and the workpieces are gripped or released by the jaw members 3 and 3. At this time, the scale number on the scale 33 moving in synchronism with the drive rod 9 is read by the reader 34, and the signal waveform output from the reader 34 is molded by the waveform molding machine 35 to form a digital signal. The operation position of the jaw members 3 and 3 is detected with respect to the entire open / close stroke by being sent to the controller and processed.

In addition, the drive section 4, the position detection section 5 and the linear guide mechanism 6 is located in the vicinity of the casing 2, the width of the casing 2, that is, the installation area of the jaw members (3, 3), Since it is assembled efficiently so that it can be accommodated in inside, even if the said position detection part 5, the linear guide mechanism 6, etc. are newly added, a chuck does not enlarge by this. Further, by providing the linear guide mechanism 6 between the drive unit 4 and the position detection unit 5, the scale 33 can be stably shifted in a state synchronized with the drive rod 9, and in particular, Even if the drive rod 9 and the relay shaft 20a are not on the same axis line, the scale 33 and the levers 21 and 21 are reliably and stably passed through the relay plate 20 by the drive rod 9. It can be operated.

Fig. 4 shows a second embodiment of the present invention, in which the chuck 1B of the second embodiment uses an air cylinder mechanism 50 that uses air pressure as a driving source for opening and closing the jaw members 3 and 3. This is different from the first embodiment. The air cylinder mechanism 50 includes a cylindrical cylinder member 51 having two ports 52a and 52b on the side, a piston 53 slidably accommodated in the cylinder member 51, and the piston ( And a head cover 54 which closes the open end of the cylinder member 51 and the air cylinder mechanism 50 is connected to the cylinder portion 10 of the drive unit 4. Housed in).

In the second embodiment, the piston is alternately supplied and discharged from the two ports 52a and 52b to the first pressure chamber 55a and the second pressure chamber 55b on both sides of the piston 53. By sliding 53, the drive rod 9 is linearly reciprocated.

By using the air cylinder mechanism 50 as a drive source for opening and closing the jaw members 3 and 3 as in the second embodiment, a larger gripping force than in the case of using the linear motor 8 as in the first embodiment is achieved. You can get it.

In addition, since the structure and operation | movement except having mentioned above about 2nd Embodiment are substantially the same as 1st Embodiment, the same code | symbol as 1st Embodiment is attached | subjected to the same principal component, and description is abbreviate | omitted.

As described above, according to the present invention, it is possible to detect the operation position of the jaw member for the entire stroke, and at the same time, the chuck has a reasonable structure in which the drive unit, the position detection unit, and the linear guide mechanism are efficiently assembled in the casing so that the chuck is not enlarged. You can get it.

Claims (9)

A plurality of jaw members provided on the axial distal end portion of the casing so as to be opened and closed in a direction crossing the axis line of the casing to hold the workpiece; A driving part having a driving rod for linear reciprocating motion in a direction parallel to the axis of the casing, the driving part being provided at a portion on the axial base end side of the casing on one of the left and right half sides of the casing; A scale for linearly reciprocating in a direction parallel to the axis of the casing in synchronism with the drive rod, and a reader fixed at a predetermined position on the casing to read the scale engraved on the scale, A position detecting unit installed at a position adjacent to the driving unit and capable of detecting an operating position of the jaw member with respect to the entire stroke; A linear guide mechanism installed between the driving unit and the position detecting unit to guide linear reciprocating movement of the scale; And Chuck having a position detection function is provided between the jaw member and the drive unit having a converter mechanism for converting the linear reciprocating motion of the drive rod into the opening and closing operation of the jaw member. The apparatus of claim 1, wherein the converter mechanism includes two levers for opening and closing the jaw member by swinging, and a relay plate for connecting the levers to the drive rod, wherein the relay plate is positioned on the center of the chuck. A relay shaft is provided, and the relay shaft is pivoted so that the proximal end of each lever can be rotated by a common support shaft, and the relay plate includes a scale supporting member for supporting the drive rod and the scale. Chuck having a position detection function, characterized in that connected to the transition through the relay plate at different positions in between. The linear guide mechanism includes a guide rail and a slider slidable along the guide rail, the guide rail is fixed to the outer wall of the driving unit in parallel with the driving rod, and the slider is attached to the scale side. Chuck with a position detection function, characterized in that. The linear guide mechanism includes a guide rail and a slider slidable along the guide rail, the guide rail is fixed to the outer wall of the driving unit in parallel with the driving rod, and the slider is attached to the scale side. Chuck with a position detection function, characterized in that. The chuck having a position detection function according to claim 2, wherein the drive rod and the relay plate are connected to each other in a floating manner so as to have a degree of freedom in the inclination direction therebetween. 5. The chuck having a position detection function according to claim 4, wherein the drive rod and the relay plate are connected to each other in a floating manner so as to have a degree of freedom in the inclination direction therebetween. The chuck having a position detection function according to claim 1, wherein the driving unit includes a linear motor operated by electromagnetic force, and is configured to advance the driving rod forward and backward with the linear motor. 8. A cylindrical magnetic frame according to claim 7, wherein the linear motor is made of a magnetic body, a non-magnetic bobbin accommodated in the magnetic frame, a plurality of magnetic coils wound around the bobbin, and axially slidable in the bobbin. And a piston assembly connected to the driving rod, wherein the piston assembly is formed by attaching a plurality of permanent magnets having a round annular shape to an outer circumference of the driving rod by sandwiching a yoke therebetween. Chuck with position detection function. 2. The position detection function according to claim 1, wherein the drive portion includes a fluid pressure cylinder mechanism that is operated by fluid pressure, and is configured to advance the drive rod back and forth with the fluid pressure cylinder mechanism. chuck.