JP2005279861A - Workpiece seating detecting mechanism of workpiece positioning device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a workpiece seating detecting mechanism capable of sufficiently securing hardness of a workpiece seating part in addition to an accurate seating detection of a workpiece, to not only simplify structure of the workpiece seating part and structure of the detection mechanism for detecting the seating of workpiece but also facilitate the maintenance. <P>SOLUTION: A sensor operating member 16 for operating a sensor for detecting the seating of the workpiece 13 is mounted on a clamping device 1 to be reciprocatively movable in an axis direction of a positioning pin 14 on the workpiece seating part 9. In the sensor operating member 16, a plurality of projecting elements 16c pressed and moved together with the sensor operating member 16 in contact with the workpiece 13 are projectingly provided around the positioning pin 14. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a workpiece seating detection mechanism for detecting that a workpiece is seated on a workpiece seating portion in a workpiece positioning device for positioning a workpiece such as a plate material to be held at a fixed position when processing such as welding. About.

  As such a workpiece seating detection mechanism, for example, there is one described in Patent Document 1 (Japanese Patent Laid-Open No. 2001-162469) and one described in Patent Document 2 (Japanese Patent Laid-Open No. 2002-225759). In the former, a workpiece seating surface is formed around a part of the tip surface of the clamp device body that is a workpiece positioning device, that is, around the root of the positioning pin with which a positioning hole provided in the workpiece is fitted. A detector is provided in the formed concave notch, and the detector directly detects that the receiving surface of the workpiece is in contact with (sitting on) the workpiece seating surface. In the latter, a single detection pin is provided on the workpiece seating surface so that it can protrude and retract, and a shaft connected to the detection pin is slidably mounted on the clamp device body, and the detection pin is pushed by the workpiece to move through the shaft. The proximity switch is activated.

However, according to these, there are the following problems.
(1) Although the workpiece is guided by the positioning pins and is seated on the workpiece seating surface, the workpiece may be seated in a state where the workpiece receiving surface is inclined with respect to the workpiece seating surface. In such a case, in the former prior art, the workpiece does not contact the detector embedded in the workpiece seating surface, and the seating cannot be detected. In the latter prior art, the detection pin is not pushed by the workpiece, or the amount of pushing is insufficient, so that the seating cannot be detected accurately.

(2) In particular, in the case of the latter prior art, as shown in FIG. 14, the workpiece seating surface 51 on which the workpiece 50 is seated is formed in an annular shape around the root portion of the positioning pin 52. Since the detection pin 53 protrudes so as to be able to appear and retract, the workpiece 50 is not perpendicular to the workpiece seating surface 51 by the detection pin 53, and is tilted as shown in FIG. The workpiece 50 is in a floating state without being in close contact with the entire surface of the workpiece seating surface 51. In such a case, the detection timing of a proximity switch (not shown) operated by the detection pin 53 is delayed or a detection failure occurs.

(3) Since the workpiece seating surface on which the workpiece receiving surface repeatedly comes into contact needs to be hardened to prevent wear and the like, it is usually subjected to steel quenching treatment. If a detection portion is provided on the surface so that the workpiece directly contacts the surface, or the detection pin is made to protrude and retract, it becomes difficult to secure a predetermined hardness as the workpiece seating surface.

(4) In the case of the former prior art, the workpiece seating portion of the clamp device body is a dedicated structure for seating detection, that is, a concave notch is formed on the workpiece seating surface which has a narrow area in the first place. The sensor must be installed inside the unit, and the sensor must maintain a predetermined durability even in a narrow area where the workpiece repeatedly comes into direct contact. Severe conditions are also imposed.

(5) In the case of the latter prior art, the detection pin is mounted on the workpiece seating surface so that it can be moved in and out, and the shaft connected to the detection pin must be mounted slidably on the clamp device body. The cost increases and maintenance is troublesome.
JP 2001-162469 A JP 2002-225759 A

  The object of the present invention is to solve such problems and to accurately detect the seating of the workpiece, and to ensure sufficient hardness of the workpiece seating portion, and to further improve the structure of the workpiece seating portion and the workpiece seating. The present invention provides a workpiece seating detection mechanism that not only simplifies the structure of the detection mechanism for detection but also facilitates maintenance of these.

  The workpiece seating detection mechanism according to the present invention is mounted on a workpiece positioning device so that a sensor actuating member for actuating a sensor for detecting the seating of a workpiece can reciprocate in the axial direction of the positioning pin on the workpiece seating portion. The sensor actuating member is characterized in that a plurality of protrusions that are pushed together with the sensor actuating member in contact with the workpiece are projected around the positioning pins.

In the preferred form, the workpiece positioning device has clamping means for clamping the workpiece positioned by the positioning pin on the workpiece seating portion.
A return spring for returning the latter to the original position is interposed between the workpiece seat and the sensor operating member.
The sensor operating member is provided with a pin through hole that allows the positioning pin to pass therethrough.

  Between the sensor actuating member and the workpiece positioning device main body, there is provided guide means for guiding the sensor actuating member to move straight while preventing the sensor actuating member from tilting and rotating. The guide means includes a plurality of guide pieces projecting from the sensor actuating member along the outer peripheral surface of the clamp device main body, and a guide provided on the outer peripheral surface of the workpiece positioning device main body for slidably guiding the guide pieces. Can be configured with grooves.

  The sensor actuating member preferably has a shape that can cover at least the upper surface of the workpiece seating portion around the positioning pin, and serves as a cover that covers the upper surface of the workpiece seating portion and the outer peripheral surface of the workpiece seating portion. Better.

The sensor is attached to the outer surface of the workpiece positioning device that is not covered with the sensor actuating member.
In addition, although the sensor can be directly operated by the sensor operating member, it is preferable to provide a sensor sensitive element that follows the sensor operating member and acts on the sensor between the sensor operating member and the sensor. The sensor sensor may be separated from the sensor actuating member, but may be integrated.

  The sensor is preferably a non-contact type such as a proximity switch or an optical sensor.

  According to the present invention, the plurality of protrusions protruding from the sensor operating member around the positioning pin are pushed together with the sensor operating member by the work, and the sensor is operated by the sensor operating member. Therefore, even if the workpiece is tilted or distorted, the seating can be accurately detected. In addition, since the workpiece is received by a plurality of protrusions of the sensor operating member, the hardness of the workpiece seating portion can be sufficiently secured, and the structure of the workpiece seating portion and the structure of the detection mechanism for detecting the workpiece seating can be simplified. The maintenance of these becomes easy.

  According to the invention which concerns on Claim 2, since the workpiece | work positioned with the positioning pin is clamped on a workpiece | work seating part, a workpiece | work can be positioned reliably. Further, by having the clamping means, the apparatus can be made compact, and further space saving can be realized by providing the clamping means inside the pin.

  According to the invention which concerns on Claim 3, cushioning property can be given to a sensor action member with a return spring.

  According to the fourth aspect of the present invention, since the sensor operating member is provided with the pin through-hole through which the positioning pin passes, the sensor operating member can be moved straight along the positioning pin, and the seating detection accuracy is improved. Can be planned.

  According to the fifth aspect of the present invention, since the sensor actuating member and the clamp device main body are provided with guide means for guiding the rectilinear advance while preventing the tilt and rotation of the sensor actuating member, the sensor actuating member is provided. Is pushed straight by the workpiece, it will go straight no matter what the contact state with the workpiece, so if the contact state with the workpiece is bad as in the past, the sensor detection timing will be delayed or the detection will be poor There is nothing wrong.

  According to the invention of claim 6, since the plurality of guide pieces projecting from the sensor operating member slide along the guide grooves provided on the outer peripheral surface of the clamp device body, the inclination of the sensor operating member can be reduced. Smooth straight running while preventing rotation.

  According to the invention which concerns on Claim 7, since the upper surface of a workpiece | work seating part can be covered with a sensor operation member around a positioning pin, the upper surface can be protected and adhesion of welding waste etc. can be prevented.

  According to the invention of claim 8, since the sensor actuating member also serves as a cover that covers the upper surface of the workpiece seating portion and the outer peripheral surface of the workpiece seating portion, the workpiece seating portion can be protected more effectively, and the sensor It is possible to prevent the actuating member from being tilted and perform the straight traveling more reliably.

  According to the ninth aspect of the invention, since the sensor is attached to the outer surface of the clamp device that is not covered with the sensor operating member, the sensor can be easily replaced and maintained.

  According to the tenth aspect of the present invention, since the sensor is sensitive to the sensor sensitive element driven by the sensor actuating member and performs seating detection, the sensor can be installed away from the workpiece seating surface, and the installation position is flexible. Can be given.

  According to the eleventh aspect of the present invention, since the sensor sensitive element is provided integrally with the sensor actuating member, the number of parts can be reduced and the maintenance is also improved.

  According to the invention which concerns on Claim 12 and 13, since the detection by a sensor can be performed non-contactingly, durability is good.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

The first embodiment uses a proximity switch as a sensor for detecting the seating of a workpiece.
As shown in FIGS. 1 to 6, a clamping device A, which is an example of a workpiece positioning device, is directly connected to a base end (lower end) of a main body 1, that is, a main body 1 and a cylinder cover 3 of the pneumatic cylinder 2. And a pair of clamp arms 4 (only one shown) and a piston rod 5 of the pneumatic cylinder 2 are connected by a pin 6 inside the main body 1 as shown in FIG. A bent guide groove 7 is provided in the clamp arm 4, and a guide pin 8 provided in the main body 1 is slidably fitted in the guide groove 7.

  The workpiece seating portion 9 of the main body 1 is provided with a workpiece washer 11 that is a short cylindrical body with a hook on the tip cover 10 of the main body 1, and the tip surface of the workpiece washer 11 is used as a workpiece seating surface 12.

  A positioning pin 14 for positioning the workpiece 13 is fixed to the tip cover 10, penetrates the workpiece washer 11 and protrudes from the workpiece seating surface 12, and a tip flange 4 a of the clamp arm 4 is formed on the positioning pin 14. It swings within the slit 14a.

  Then, as shown in FIG. 7, while the pneumatic cylinder 2 is fixed at a fixed position, the workpiece 13 which is a thin plate is lowered, and the positioning pin 14 is inserted into the positioning hole 15 provided therein to perform positioning. The distal end flange 4a of the clamp arm 4 is inserted into and removed from the positioning hole 15 of the work 13, and the pair of clamp arms 4 are swung by the advancement and retraction of the piston rod 5, and the distal end flange 4a The workpiece 13 can be clamped and released from the workpiece seating surface 12, which is the fixed tip surface.

  The workpiece seating detection mechanism B according to the present invention is incorporated in such a clamp device A in the form of being externally attached around the workpiece seating portion 9 as follows.

  That is, a sensor operating member 16 that also serves as a cover that covers a part of the tip cover 10 and the periphery of the workpiece seating portion 9 is fitted to the outside of the tip cover 10 of the main body 1 so as to be movable up and down. A plurality of return springs (coil springs) 17 for returning and raising the sensor operation member 16 are interposed between the ring-shaped ceiling portion 16a and the upper surface of the tip cover 10.

  In the center of the ceiling portion 16 a of the sensor operating member 16, a circular opening portion 16 b that allows the work washer 11 to penetrate with the positioning pins 14 is formed. At a plurality of locations (for example, three locations) on the periphery of the opening portion 16b, protrusions 16c rising along the outer peripheral surface of the positioning pin 14 at a slight interval are integrally provided. These protrusions 16 c protrude from a slit provided in the work washer 11 to above the work seating surface 12. In this example, there are three protrusions 16c. However, at least two protrusions 16c may be used.

  Further, guide pieces 16e are integrally formed at a plurality of locations (for example, three locations) on the lower peripheral edge of the peripheral wall portion 16d of the sensor actuating member 16, and these guide pieces 16e are formed on the outer peripheral surface of the main body 1. A guide pin 18a that is slidably fitted into the vertically long guide groove 18 is provided. The sensor actuating member 16 uses the guide pin 18a and the guide groove 18 as guide means and is guided in the vertical movement while being prevented from tilting and rotating, and is restricted from rising by a predetermined amount by the guide pin 18a. Therefore, the guide pin 18 a also serves as an upper limit stopper for the sensor operating member 16. The guide piece 16e has a length that always covers the sensor actuating member 16 so that welding waste or the like does not enter the guide groove 18, that is, a length that can cover the guide groove 18 even when the sensor actuating member 16 rises to the upper limit. It has become.

  Furthermore, a pin-shaped sensor sensor 19 is vertically suspended on the lower surface of the ceiling portion 16 a of the sensor actuating member 16, and the sensor actuating member 16 is returned around the sensor sensor 19 together with the sensor sensor 19. A return spring (coil spring) 17a to be raised is installed. The sensor sensor 19 extends through the hole of the collar part of the work washer 11 and the hole of the tip cover 10 to the lower side thereof, and a magnetic body (for example, a permanent magnet) 20 attached to the lower end of the sensor sensor 19. However, the proximity switch 21 which is a sensor attached to the outer peripheral surface of the main body 1 can be operated. The attachment position of the proximity switch 21 is a height that is not covered by the sensor operating member 16.

  As shown in FIG. 7A, the workpiece seating detection mechanism B configured as described above is in a standby state where the workpiece 13 is not in contact with the sensor operating member 16, and the sensor operating member 16 is raised to the upper limit position. The child 16c protrudes above the workpiece seating surface 9, and the magnetic body 20 at the lower end of the sensor sensor 19 remains at a height at which the proximity switch 21 is not operated.

  The workpiece 13 is lowered toward the positioning pin 14, the positioning hole 15 of the workpiece 13 is fitted into the positioning pin 14, and the lower surface around the positioning hole 15 of the workpiece 13 is the protrusion of the sensor actuating member 16. When abutting against 16c, the sensor actuating member 16 is pushed downward together with the protrusion 16c by the work 13 against the return springs 17 and 17a.

  As shown in FIG. 7B, when the lower surface around the positioning hole 15 of the workpiece 13 is seated on the workpiece seating surface 12, the magnetic body 20 at the lower end of the sensor sensor 19 that has been lowered together with the sensor actuating member 16 is moved to the proximity switch. 21 is operated and the proximity switch 21 is turned on, so that the seating of the work 13 is electrically detected.

  By this detection, the compressed air supply path to the pneumatic cylinder 2 is switched, the piston rod 5 is lowered as shown in FIG. 7C, and the workpiece 13 is moved to the workpiece seating surface by the tip flange 4a of the clamp arm 4. 12 is fixed.

Example 2 shown in FIG. 8 uses an optical sensor as a sensor for detecting the seating of a workpiece.
That is, instead of the proximity switch 21 in the first embodiment, an optical sensor 22 composed of a light emitting portion 22a and a light receiving portion 22b is attached to the outer peripheral surface of the main body 1, and from one place of the peripheral wall portion 16d of the sensor operating member 16. A thin plate sensor sensor 23 is integrally suspended. Then, the sensor actuating member 16 is pushed downward by the work 13, and the tip of the sensor sensor 23 intervenes between the light emitting part 22a and the light receiving part 22b of the sensor 22, and thereby the light from the light emitting part 22a. By blocking the light, it is detected that the workpiece 13 is seated on the workpiece seating surface 12, and the others are the same as in the first embodiment.

  In Embodiment 3 shown in FIGS. 9 to 13, the sensor operating member 16 is shaped like a + annular plate and covers only the upper surface of the workpiece seating portion 9 around the positioning pin 14. Is substantially the same as in the first embodiment.

  In the above embodiments, the case where a proximity switch is used as a sensor and the case where an optical sensor is used have been described. However, it goes without saying that other types of sensors may be used. One or more clamp arms may be provided. Furthermore, although the clamp device is taken as an example of the workpiece positioning device, it is not limited to the clamp device.

It is a front view of Example 1 of the present invention. It is also a plan view. It is a bottom view. It is a right view. It is a left side view. It is a rear view. It is sectional drawing which shows operation | movement of Example 1, (A) is a standby state, (B) is a seating state, (C) is a clamped state. FIG. 6 is a cross-sectional view illustrating an operation of the second embodiment, where (A) is a standby state, (B) is a sitting state, and (C) is a clamped state. 6 is a side view of Example 3. FIG. FIG. 6 is a side view on the opposite side of Example 3. 6 is a plan view of Example 3. FIG. 6 is a front view of Example 3. FIG. It is sectional drawing in the II line | wire of FIG. It is principal part sectional drawing of a prior art example.

Explanation of symbols

A Clamping device 1 which is a workpiece positioning device Body 2 Pneumatic cylinder 3 Cylinder cover 4 Clamp arm 4a Tip flange 5 Piston rod 6 Pin 7 Guide groove 8 Guide pin 9 Workpiece seating portion 10 Tip cover 11 Work washer 12 Workpiece seating surface 13 Workpiece 14 positioning pin 14a slit 15 positioning hole 16 sensor operating member 16a ceiling 16b opening 16c protrusion 16d peripheral wall 16e guide piece 17 / 17a return spring 18 guide groove 18a guide pin 19 sensor sensor 20 magnetic body 21 proximity switch 22 light Sensor 22a Light emitting part 22b Light receiving part 23 Sensor sensitive element

Claims (13)

  In a workpiece positioning device that positions a positioning hole provided in a workpiece with a positioning pin of the workpiece positioning device and positions the workpiece on a workpiece seating portion of the workpiece positioning device, a sensor operating member that operates a sensor that detects the seating of the workpiece, Mounted on the workpiece positioning device so as to be reciprocally movable in the axial direction of the positioning pin on the workpiece seating portion, and a plurality of the sensor operating members are pressed together with the sensor operating member in contact with the workpiece. The workpiece seating detection mechanism of the workpiece positioning device, characterized in that the projections of the workpiece are projected around the positioning pins.   The workpiece seating detection mechanism according to claim 1, wherein the workpiece positioning device includes a clamping unit that clamps the workpiece positioned by the positioning pin on the workpiece seating portion.   The workpiece seating detection mechanism according to claim 1, wherein a return spring for returning the latter to the original position is interposed between the workpiece seating portion and the sensor operating member.   The workpiece seating detection mechanism according to claim 1, wherein the sensor operating member is provided with a pin through-hole through which the positioning pin passes.   The workpiece according to any one of claims 1 to 4, wherein a guide means is provided between the sensor actuating member and the workpiece positioning device main body to guide the sensor actuating member in a straight line while preventing inclination and rotation of the sensor actuating member. Seating detection mechanism.   A guide means is provided on the outer peripheral surface of the work positioning device main body for slidably guiding the plurality of guide pieces projecting from the sensor operating member along the outer peripheral surface of the work positioning device main body. The workpiece seating detection mechanism according to claim 5, wherein the workpiece seating detection mechanism is a guide groove.   The workpiece seating detection mechanism according to any one of claims 1 to 6, wherein the sensor actuating member has a shape capable of covering at least an upper surface of the workpiece seating portion around the positioning pin.   8. The workpiece seating detection mechanism according to claim 7, wherein the sensor actuating member also serves as a cover that covers the upper surface of the workpiece seating portion and the outer peripheral surface of the workpiece seating portion.   9. The workpiece seating detection mechanism according to claim 7, wherein the sensor is attached to an outer surface of the workpiece positioning device that is not covered with the sensor operating member.   The workpiece seating detection according to any one of claims 1 to 9, wherein a sensor sensor is provided between the sensor actuating member and the sensor to act on the sensor following the sensor actuating member. mechanism.   The workpiece seating detection mechanism according to claim 10, wherein the sensor sensitive element is provided integrally with the sensor operating member.   The workpiece seating detection mechanism according to claim 1, wherein the sensor is a proximity switch.   The workpiece seating detection mechanism according to claim 1, wherein the sensor is an optical sensor.

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