JP2006272523A - Workpiece carrier device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a workpiece carrier device which has its entire structure simplified and downsized, is reduced in cost by using a low-thrust motor, can smoothly and positively carry a workpiece, and ensures the safety of carrying operation by immediately stopping the carrying operation when a carrying load of a predetermined value or more is applied to the device. <P>SOLUTION: The workpiece carrier device is constructed by connecting a pair of right and left first arms 6 and a pair of right and left second arms 7 to each other as a turning pair to set up a pantograph-like link mechanism 8, and operating the pantograph-like link mechanism 8 so as to contract/extend in a carrying direction by setting a base 5 arranged at a midpoint of a carrying passage as a reference point. Thus the workpiece W mounted and borne on a slide guide 2 is carried along a constant passage in a manner sliding on the slide guide 2. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a work transfer device used when, for example, a work such as a workpiece is transferred between processing stations such as various machine tools scattered in a factory.

  As this type of work transfer device, a multi-axis multi-joint robot is used, which is configured to hold the work with a robot hand attached to the tip of the arm and carry it in the air to the next processing station or the like, or A workpiece support table that is slidably supported on the slide base in the workpiece transfer direction is driven and moved along the slide base via a chain conveyor such as an endless chain to convey the workpiece linearly. (For example, refer to Patent Document 1) is generally known.

However, in the case of a transfer device using a multi-axis multi-joint robot, the workpiece is gripped and transferred in the air, so a large robot must be used to enable transfer of a heavy workpiece. Therefore, the whole conveying apparatus becomes large and heavy. In addition, in order to operate the robot arm and robot hand smoothly and precisely, it is necessary to use an expensive drive source such as a servo motor and a control device, and it is inevitable that the initial cost and running cost of the entire transfer device will increase. In addition, the robot control method is complicated program control, its operation setting is difficult, and a skilled person is required.

On the other hand, in the case of a transport device mainly composed of a chain conveyor, it is necessary to perform maintenance periodically in a short cycle in order to cope with the chain growth over time, and the maintenance cost increases. Further, since the chain rubs against the guide during the workpiece transfer operation, there is a problem in that a large noise is generated and the working environment and the surrounding environment are deteriorated.

In order to solve the problems of the conventional general workpiece transfer device, the present applicant places a workpiece on a slide guide provided along the transfer path, and sets a locking member for locking the workpiece from above in parallel. A bracket that can be pivotally connected to one end side of the posture maintaining means by the linkage mechanism, and a bracket that can be moved up and down along an elevating guide standing on an intermediate portion of the transport path is connected to the other end side of the posture maintaining means. The workpiece is transported in a state of sliding on the slide guide by moving the locking member so as to draw a trajectory substantially parallel to the transport path by a combined motion of the up-and-down motion of the head and the swing motion of the posture maintaining means. A workpiece transfer apparatus configured as described above has already been proposed (see, for example, Patent Document 2, hereinafter referred to as a previously proposed technique).

Japanese Patent Laid-Open No. 2004-001990 JP 2003-201008 A

  However, in the case of the technology proposed by the present applicant, the workpiece can be conveyed while being slid on the slide guide, and the noise can be reduced as compared with a conveying device mainly composed of a chain conveyor. It requires posture maintaining means, bracket lifting means and drive means for synchronizing and swinging both means, and the structure of the apparatus is very complicated and easy to enlarge. As in the case of the type, since an expensive drive source such as a servo motor and a control device must be used, an increase in the cost of the entire transport device is inevitable. In addition, complicated program control must be adopted as a control method, and there remains a problem that operation setting is difficult and only an expert can handle it.

  The present invention has been made in view of the above circumstances, and its purpose is to facilitate smooth and reliable conveyance of a workpiece while simplifying the overall structure, reducing the size, and reducing the cost by using a low thrust motor. In addition, it is an object of the present invention to provide a work transfer device that can immediately stop the transfer when a transfer load of a certain level or more is applied to ensure safety.

  The work conveying apparatus according to the present invention devised to achieve the above object is for conveying a work from an upstream side to a downstream side of a certain conveying path along a slide guide that slidably supports the work. And a pair of left and right first arms and a pair of left and right second arms that turn and connect to a pair of pantograph-type link mechanisms. Mounted on the slide guide on a mounting base that is rotatably supported around a longitudinal support shaft on a base standing upright at the bottom of the base and pivotally connected between the free ends of a pair of left and right second arms. A work conveyance claw that can be locked to the work supported or can be attracted to the lower surface of the work is provided, and the first arm of the pantograph type link mechanism is driven to rotate in the forward and reverse directions around the longitudinal support shaft. At the same time, arm driving means for rotating the second arm around the supporting shaft for connection with the first arm in a direction opposite to the first arm is provided, and the first arm and the second arm are mutually connected via the arm driving means. The pantograph-type link mechanism is driven to rotate in the reverse direction and is contracted and extended in the transport direction with the base as a base point, so that the workpiece is transported while sliding on the slide guide. It is characterized by.

  According to the workpiece conveyance device according to the present invention having the above-described characteristic configuration, the pantograph-type link mechanism that can be installed in a low volume in a horizontal plane and the first and second arms of the link mechanism rotate in directions opposite to each other. Since it is composed only of arm driving means to be driven, and does not require any bulky lifting means as found in the already proposed technology, the structure of the entire apparatus can be simplified and miniaturized. In addition, since the workpiece weight is transferred to the slide guide for sliding transport, it is possible to use a low-thrust motor as the arm drive means, and the cost of the entire apparatus can be reduced. The workpiece can be transported smoothly and reliably while sliding on the slide guide as the pantograph-type link mechanism contracts and extends in the transport direction. Kill.

Also, as a control method, simple control means such as inverter control can be adopted, and operation setting and maintenance can be simplified. In addition, since it is possible to use a low-thrust motor, a work load more than a certain level has been applied due to a collision or contact with a workpiece that has been accidentally placed in the transport path or an operator who has accidentally entered the transport path. At this time, there is an effect that the conveyance can be stopped immediately to ensure the safety of the conveyance.

  In the workpiece transfer apparatus according to the present invention, the slide guide may be a long plate-like or bar-like one along the transfer path, and particularly, juxtaposed along the transfer direction as described in claim 2. It is desirable to comprise a plurality of free rotating roller groups. In this case, the slip resistance against the workpiece is reduced, so that a lower thrust motor can be used, further cost reduction can be achieved, and the safety can be further improved by ensuring the emergency stop when the transport load is applied. it can.

  Further, as the arm driving means in the work transfer device according to the present invention, as described in claim 3, the first arm in the pantograph type link mechanism is driven to rotate in the forward and reverse directions around the longitudinal support shaft. 5. The motor and a second motor that rotates the second arm around the connecting support shaft in a direction opposite to the first arm are used in a synchronous operation state, or as in claim 4. A first motor for driving the first arm in the pantograph type link mechanism to rotate in the forward and reverse directions around the longitudinal support shaft, and a winding power transmission mechanism for transmitting the rotational driving force of the first motor to the second arm. However, in the case of the latter one-motor, the first arm and the second arm can be reliably driven synchronously with no timing deviation. It can be performed with favorable and stable predetermined workpiece conveying due to shrinkage and expansion behavior of the formula linkage.

Furthermore, in the workpiece transfer apparatus according to the present invention, as in claim 5, a direction changing device that rotationally drives the base around a vertical axis is installed at an intermediate portion of the workpiece transfer path. When the mounting base on the second arm side of the pantograph-type link mechanism is moved to the direction change position on the base of the apparatus, the mounting base and the work conveying claw are moved in sliding contact with the cam follower attached to the lower part of the mounting base. By providing the inclined cam to be raised, the direction of the workpiece can be changed in the middle of conveyance, and the direction change can be implemented very easily structurally compared to the already proposed technology.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic plan view showing a first embodiment of a workpiece transfer device according to the present invention, FIG. 2 is a side view of FIG. 1, and the workpiece transfer device 1 shown in these drawings is, for example, a machine tool or the like A work guide such as a workpiece is transported between two first and second processing stations S1 and S2 in which a slide guide 2 is slidably received and supported. Are provided in parallel to each other on both the left and right sides. As clearly shown in FIGS. 3 and 4, these slide guides 2 have a plurality of rollers 4 arranged side by side along a workpiece conveying direction A in a long rail 3 having a substantially U-shaped cross section. Each part is supported so as to be freely rotatable with a part exposed above the rail 3. Although not shown, the slide guide 2 may be a long plate-shaped or bar-shaped guide constructed along the left and right sides of the conveyance path between the processing stations S1 and S2.

  5 is a base erected from the floor surface FL to a position lower than the position of the slide guide 2 at an intermediate portion of the transfer path, that is, an intermediate position M between the first and second processing stations S1 and S2. On the base 5, the base ends of the pair of left and right first arms 6 in the pantograph type link mechanism 8, in which a pair of left and right first arms 6 and a pair of left and right second arms 7 are coupled to each other, are vertically supported. The shaft 9 is rotatably supported around the axis. Further, a plate-like mounting base 10 for mounting a work conveying claw, which will be described later, is pivotally connected between the free end portions of the pair of left and right second arms 7 in the pantograph type link mechanism 8. 10, a vacuum cup-shaped work conveyance claw 11 that can be attracted to the lower surface of the work W placed and supported on the slide guide 2 is attached.

In addition, as the work conveyance nail | claw 11, the thing of the vacuum cup shape which can adsorb | suck to the lower surface of the workpiece | work W is preferable, but when the workpiece | work W is an engine case and has a hole for fixation with respect to a chassis, the It may be a pin-shaped latching claw that engages with the hole.

  Arm driving means for rotationally driving the first arm 6 in the pantograph type link mechanism 8 in the forward and reverse directions as indicated by arrows ab (see FIG. 5B) around the axis of the longitudinal support shaft 9. The first motor 12 having an output shaft (not shown) directly connected to the longitudinal support shaft 9 is fixedly held on the base 5, and the second arm 7 in the pantograph link mechanism 8 is replaced with the first arm 6. As shown by an arrow cd (see FIG. 5B) around the axis of the pivot connection support shaft 13, as arm drive means for rotationally driving in the direction opposite to the first arm 6, A second motor 14 in which an output shaft (not shown) is directly connected to the pivot connection support shaft 13 is fixedly held on the lower surface of the first arm 6. The first motor 12 and the second motor 14 are configured to operate synchronously via a power supply circuit (not shown).

The second arm 7 in the pantograph-type link mechanism 8 is driven to rotate in the forward and reverse directions as indicated by arrows cd around the axis of the pivot connection support shaft 13 with the first arm 6. As a means, the second motor 14 is not used, and the rotational driving force of the first motor 12 is connected to the pivot support in a reverse rotation state via a winding power transmission mechanism (not shown) such as a chain or a belt. You may comprise so that it may transmit to the spindle 13. FIG.

In the workpiece transfer apparatus 1 configured as described above, as shown in FIG. 5A, the first arm 6 and the second arm 7 in the pantograph link mechanism 8 are set in the transfer direction with the base 5 as a base point. The workpiece conveying claw 11 is transferred to the first processing station S1 by maximally extending to the downstream side (left side in the drawing). In this state, the workpiece W is placed on the slide guide 2 and the workpiece conveyance claw 11 is attracted to the lower surface of the workpiece W.

Next, as shown in FIG. 5B, the first motor 12 and the second motor 14 are driven synchronously so that the first arm 6 in the pantograph type link mechanism 8 is moved around the axis of the longitudinal support shaft 9 by an arrow. Simultaneously with the rotational drive in the direction b, the second arm 7 is rotationally driven in the direction of the arrow c around the pivotal connection support shaft 13, whereby the pantograph-type link mechanism 8 starts to contract and transports the workpiece. The nail | claw 11 is horizontally moved linearly. Along with the movement of the workpiece conveying claw 11, the workpiece W is conveyed toward the upstream side (right side in the drawing) in the conveying direction while sliding on the slide guide 2, and the pantograph link mechanism 8 is maximally contracted. At this stage, as shown in FIG. 5C, the intermediate position M between the first and second processing stations S1 and S2 is reached.

When the intermediate position M is reached, as shown in FIG. 5D, the first arm 6 in the pantograph type link mechanism 8 is continued through the first motor 12 and the second motor 14 to continue the longitudinal support. A pantograph type link mechanism is driven by rotating in the direction of arrow b around the axis of the shaft 9 and simultaneously rotating in the direction of arrow c around the axis of the pivot connecting support shaft 13 at the same time as the second arm 7. 8 starts the extension operation, and the workpiece conveyance claw 11 is linearly moved to the upstream side in the conveyance direction linearly. Along with the movement of the workpiece conveying claw 11, the workpiece W is conveyed toward the upstream side in the conveying direction while sliding on the slide guide 2, and when the pantograph type link mechanism 8 is extended to the maximum extent, FIG. As shown in (E), the workpiece W is carried into the second processing station S2.

Thereafter, by switching the rotation directions of the first motor 12 and the second motor 14, the first arm 6 is driven to rotate in the direction of arrow a and the second arm 7 is driven to rotate in the direction of arrow d, thereby causing the pantograph link mechanism 8 to rotate. After the pantograph link mechanism 8 contracts to the maximum and reaches the intermediate position M, the first arm 6 continues in the direction of arrow a and the second arm 7 continues in the direction of arrow d. And the pantograph link mechanism 8 is extended to move the workpiece conveyance claw 11 linearly from the upstream side in the conveyance direction A to the downstream side, as shown in FIG. Transfer and return to one processing station S1.

By repeating the above operation, the workpieces W that have been subjected to predetermined machining at the first machining station S1 are successively transferred to the second machining station S2, and the next machining is performed at the second machining station S2. It will be.

It is also possible to transport the workpiece W from the second processing station S2 to the first processing station S1 by operating the pantograph type link mechanism 8 in the reverse manner to the above-described operation.

As described above, the workpiece transfer device 1 rotationally drives the pantograph-type link mechanism 8 that can be installed low in a horizontal plane and the first and second arms 6 and 7 of the link mechanism 8 in opposite directions. Since it is composed only of the arm drive means (first and second motors 12 and 14), the occurrence of noise is reduced as in the case of using a chain conveyor, the work environment and the surrounding environment can be improved, and the maintenance frequency Therefore, it is possible to reduce the maintenance cost by reducing it to a very low level, and to simplify and miniaturize the overall structure of the apparatus.

  Further, since the weight of the work W is entrusted to the slide guide 2, even when a heavy work W is to be transported, the low thrust motors 12 and 14 can be used. Cost reduction can be realized. By using the low-thrust motors 12 and 14, a work load of a certain level or more is applied due to collision or contact with another object in which the work W is mistakenly placed in the transport path or an operator accidentally entering the transport path. In this case, it becomes possible to overcome the low thrust of the motors 12 and 14 and immediately stop the work W, thereby ensuring the safety of the conveyance.

  In particular, when the slide guide 2 is composed of a plurality of groups of free rotating rollers 4 arranged in parallel along the conveying direction, the slip resistance of the work W is reduced, so that a lower thrust motor can be used. It can be used, and further cost reduction can be achieved, and an emergency stop at the time of the transport load action can be ensured to further enhance safety.

  FIG. 6 is an enlarged plan view of a main part showing a second embodiment of the workpiece transfer apparatus according to the present invention, and FIG. 7 is a longitudinal side view taken along line XX of FIG. In the workpiece transfer apparatus 1 of the second embodiment, the workpiece transfer path extending between the first and second processing stations S1 and S2 is bent at 90 ° at the intermediate portion thereof. At an intermediate position M between the stations S1 and S2, a direction changing device 15 for reciprocatingly driving the base 5 over a rotation angle range of 90 ° around the longitudinal axis is installed.

  The direction changing device 15 includes a rotary table 16 that can be switched between forward and reverse rotation via a low thrust motor (not shown). The base 5 is fixed on the rotary table 16, and the above-described base 5 is mounted on the base 5. The pantograph-type link mechanism 8 is configured such that the base end portions of the pair of left and right first arms 6 are rotatably supported around the axis of the longitudinal support shaft 9. The base 5 is provided with a plate-like inclined cam 17, and the second arm 7 is mounted on the rotary table 16 below the mounting base 10 of the second arm 7 in the pantograph type link mechanism 8. A cam follower (roller) 18 that slides on the inclined cam 17 and raises the mounting base 10 and the work conveying claw 11 is supported.

  Moreover, the workpiece conveyance claw 11 in this 2nd Example is comprised in the form which pinches | interposes and hold | maintains the workpiece | work W from the front and back both sides of the conveyance direction. Since the other structure is the same as that of the first embodiment, the same reference numerals are assigned to the same members, and detailed descriptions thereof are omitted.

  In the workpiece conveyance device 1 of the second embodiment configured as described above, the workpiece in which the workpiece conveyance claw 11 is machined at the first machining station S1 in accordance with the expansion operation of the pantograph type link mechanism 8 and the subsequent contraction operation. The process action of latching and holding W and sliding the workpiece W to the intermediate position M is the same as in the first embodiment. When the workpiece W reaches the intermediate position M, the rotary table 16 rotates 90 ° in the direction of the arrow R, and accordingly, the base 5, the pantograph type link mechanism 8 and the workpiece W are turned 90 °. The work conveying claw 11 is carried into the second processing station S2 again with the extension operation of the pantograph link mechanism 8 and the subsequent contraction operation.

At the time of the direction change, the second arm 7 in the pantograph type link mechanism 8 moves from the position before the direction change device 15 as shown in FIG. 7A to the direction change position on the rotary table 16. When this occurs, the cam follower (roller) 18 slides on the inclined cam 17 fixed to the base 5 so that the mounting base 10, the work conveying claw 11 and the work W are raised as shown in FIG. The As a result, the lower surface of the workpiece W is lifted from the slide guide 2, and the predetermined direction change is smoothly performed without any trouble.

Further, in the second embodiment with this direction changing action, since the work conveyance claw 11 is configured so as to hold and hold the work W from both the front and rear sides in the conveyance direction, It is possible to perform the predetermined direction change more stably without causing the work W to unexpectedly leave or swing from the work conveyance claw 11 during the direction change.

In each of the above-described embodiments, the case where the pantograph-type link mechanism 8 in the single workpiece transfer device 1 is used for workpiece transfer over a relatively short distance by the expansion / contraction operation has been described. For example, as shown in FIG. By arranging a plurality of workpiece conveying devices 1 in parallel and sequentially taking over and conveying the workpiece W along the slide guide 2 by the expansion / contraction operation of the pantograph type link mechanism 8 in the plurality of workpiece conveying devices 1, It can also be applied to a long distance work transfer.

It is a schematic plan view which shows the 1st Example of the workpiece conveyance apparatus which concerns on this invention. It is a side view of FIG. It is a principal part enlarged plan view of a slide guide. It is a vertical front view in the YY line of FIG. (A)-(E) are schematic plan views explaining a workpiece conveyance process. It is an enlarged plan view of the principal part which shows the 2nd Example of the workpiece conveyance apparatus which concerns on this invention. It is a vertical side view in the XX line of FIG. It is a schematic side view which shows the other application example of the workpiece conveyance apparatus which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Work conveyance apparatus 2 Slide guide 4 Free rotation roller 5 Base 6 1st arm 7 2nd arm 8 Pantograph type link mechanism 9 Vertical support shaft 10 Mounting stand 11 Work conveyance claw 12 1st motor (link drive means)
13 Linking shaft 14 Second motor (link driving means)
15 Direction change device 17 Inclined cam 18 Cam follower W Workpiece

Claims (6)

A workpiece transfer device for transferring a workpiece from an upstream side to a downstream side of a fixed transfer path along a slide guide that slidably supports the workpiece,
The base end of the pair of left and right first arms in a pantograph-type link mechanism in which a pair of left and right first arms and a pair of left and right second arms are connected to a pair is mounted on a base erected at the lower part of the transport path And is supported by a work piece mounted and supported on the slide guide on a mounting base that is pivotally connected between the free ends of the pair of left and right second arms. A work conveying claw that can be attracted to the work bottom or is provided on the lower surface of the work, and the first arm in the pantograph-type link mechanism is driven to rotate in the forward and reverse directions around the longitudinal support shaft, and at the same time, the second arm is connected to the first arm. The pan tag is provided with arm driving means for rotating in the direction opposite to the first arm around the connecting support shaft, and the first arm and the second arm are driven to rotate in directions opposite to each other via the arm driving means. The full-type link mechanism, by the shrinkage and expansion behavior in the conveying direction of the base as the base point, a work conveying apparatus characterized by being configured to carry a workpiece in a state of sliding the slide guide above.   The work conveying apparatus according to claim 1, wherein the slide guide includes a plurality of free rotating roller groups juxtaposed along the conveying direction.   The link driving means is a first motor for driving the first arm in the pantograph-type link mechanism to rotate in the forward and reverse directions around the longitudinal support shaft, and the second arm is the first arm around the connection support shaft. The work conveying apparatus according to claim 1, comprising a second motor that rotates in the reverse direction.   The link driving means rotates a first arm of the pantograph-type link mechanism in a forward / reverse direction around the longitudinal support shaft, and a winding for transmitting the rotational driving force of the first motor to the second arm. The work conveying apparatus according to claim 1, comprising a hanging type power transmission mechanism.   A direction changing device that rotationally drives the base around a vertical axis is installed at an intermediate portion of the workpiece transfer path. The direction changing device has a base on the second arm side of the pantograph type link mechanism. 5. An inclined cam is provided for sliding the cam follower attached to the lower part of the mounting base to raise the mounting base and the work conveying claw when the mounting base moves into the direction change position. Crab transport device. The workpiece transfer device according to claim 5, wherein the workpiece transfer claw is configured to hold and hold the workpiece by sandwiching the workpiece from both front and rear sides in the transfer direction.

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