JP2002273673A - Pick-and-place unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate a stroke change while maintaining high speed operation, high repeatability and durability in a PPU using a cam. SOLUTION: A structure where a turning movement of a lever 11 following a rotation of the cam 4 slides an X arm 31 has a stroke changing guide 20 with one journaled end. The guide 20 engages with a linear guide block 16 movable on a linear guide rail 15 mounted on the lever 11, and the linear guide block 16 moved by the turning movement of the lever 11 moves the X arm 31. A change in the inclination angle of the stroke changing guide 20 adjusts the stroke of the X arm 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus used in an automatic assembling machine for performing operations such as supplying a work from a feeder or the like to an assembling jig.

[0002]

2. Description of the Related Art An apparatus for picking up (picking) a work from a feeder, transporting the work, and supplying (placing) the work to an assembling jig, a so-called pick-and-place apparatus (hereinafter referred to as a PPU).
Is used in electronic equipment assembling apparatuses and the like. The PPU is used not only for supplying the work but also as a transfer / discharge unit for packing and taking out the product.

[0003] Such PPUs are used in various fields, but recently the users are changing quickly and are becoming more fragmented, so that PPU products are frequently improved and type changes occur. ing. However, PPU
Is usually a dedicated machine according to the work to be handled, so if the size of the work changes or the work arrangement changes, even if these changes are slight, the top plate This would be a major remodeling in which the entire chuck that was mounted was changed, or the stroke was changed by changing the cam of the PPU.

[0004] When it is expected that the PPU is difficult to deal with such as changing the size of the work to be handled, a SCARA-type robot or a single-axis robot may be used. However, since the robot is a complex operation, it is expensive for high-speed work. Must use a good scalar robot. Further, robots generally have drawbacks such as low repetition accuracy for performing simple tasks, slow cycle time, high cost of the robot itself, and large space for placement.

[0005]

The structure consisting of the cam and the lever and the slide member [0006] In PPU whose main structure, high speed operation, while maintaining the height and durability of repeatability, move easily stroke (g Ppupureto range)
To provide a configuration that can change

[0006]

The PPU includes a base plate, an X arm, a cam and a lever, and further includes a variable stroke guide. These are each attached to a base plate. The base plate is a thick and strong steel plate, which supports the fulcrum shaft and the rotation shaft of each member, provides a guide portion for the X-arm, or serves as a mounting portion for a motor or a position detecting device.

The X-arm is a slider for a linear guide, and has a top plate provided with a chuck for handling a work at a distal end thereof. An X-axis slider (horizontal movement), a Z-axis slider (vertical movement), or a Y-axis slider (forward / backward movement) in rectangular coordinates are typical examples. The cam is for rotating the lever, and any type of cam may be used according to the present invention.
In PPU, a plate cam having an outer periphery as a cam surface is often used. The plate cams are arranged according to the X axis, the Z axis, and the like, and are driven by a motor attached to the base plate. The rotational position of the cam is grasped by a position detecting device, and is used for the opening / closing operation timing of a chuck for handling a work.

The lever is for transmitting a change in the outer diameter due to the rotation of the cam to the X arm, and integrally includes a driving arm which is moved by the cam and a driven arm which transmits displacement to the X arm. And is supported by a base plate on a fulcrum shaft. The lever reciprocates for a predetermined angle about the fulcrum shaft as the cam rotates. A linear guide rail is fixed to the driven arm of the lever along the longitudinal direction of the arm, and a linear guide block is attached to the linear guide rail. That is, the linear guide block can move the driven arm of the lever in the longitudinal direction. And
The linear guide block is rotatably connected to the base of the slider in the X-arm. In practice, a return spring is disposed between the X arm and the linear guide, and the base of the slider is always in contact with the roller of the linear guide block by the biasing force (ie, a structure in which the return spring is disposed).
Rotatably connected).

The variable stroke guide is a linear rail-shaped or groove-shaped guide member whose base end is rotatably supported on a base plate, and a linear guide block attached to the lever is rotatably engaged and guided. Is done. The guide block guided by the linear guide rail provided on the lever is rotatably connected to the X arm and rotatably engaged with the variable stroke guide. In the variable stroke guide, the distal end is located inside the rotation trajectory of the driven arm of the lever with respect to the base end, and the guide axis, which is the guide direction, is inclined with respect to the linear movement direction of the X arm. The fulcrum axis of the variable stroke guide may be on the proximal side or the distal side, but the direction from the proximal side to the distal side is the same. The axis (guide axis) along the guide direction of the variable stroke guide intersects with the axis (lever axis) along the guide direction of the linear guide rail provided on the driven arm of the lever, and the linear guide block always has these axes. It will be located at the intersection.

When the cam rotates and the lever rotates, the linear guide block moves and moves the X arm. The moving range (stroke) differs depending on the angle of the variable stroke guide. That is, when the base end is used as a fulcrum shaft, when the lever rotates and the distal end of the driven arm is at the most forward position (forward end), the lever axis of the driven arm and the guide of the variable stroke guide are used. The closer the intersection with the axis is to the fulcrum axis of the lever, the more X from the base side to the tip side.
The arm stroke becomes smaller. Using this change, the stroke of the PPU can be adjusted in response to the change in the size of the work. In that case, the change of other structures and peripheral devices of the PPU is not essential, and only a simple adjustment is required. When the fulcrum shaft is on the distal side, the stroke of the X arm decreases from the distal side to the proximal side.

[0011]

1 to 6 show a PP according to the present invention.
2 schematically shows the structure of U1. In the figure, the left and right are X
The axial direction and the vertical direction are the Z-axis direction. Further, the PPU 1 has a structure in which only the stroke in the X-axis direction can be adjusted. The base plate 2 constitutes a part of the machine frame in the PPU 1 and is perpendicular to the substrate 3 and
The surfaces are set up in parallel (FIG. 2). Base plate 2
An X-axis plate cam 4 and a Z-axis plate cam 5 are pivotally supported at substantially the center portions of a and 2b. A drive motor 6 is mounted above the base plates 2a, 2b, and an output shaft 7, gears 8a, 8b, 9
, The X-axis plate cam 4 and the Z-axis plate cam 5 are driven.
The X-axis plate cam 4 and the Z-axis plate cam 5 are fixed to the same cam drive shaft 10, and both rotate on a plane parallel to the base plate 2.

Reference numeral 11 denotes an X-axis lever,
2 and a driven arm 13 (FIGS. 1 and 3), and the top of the crank is rotatably supported on the base plate 2 by a fulcrum shaft s1. The position of the fulcrum shaft s1 is approximately 45 ° to the upper right of the cam rotation shaft 10. A roller 14 is attached to the tip of the drive side arm 12 as a cam follower, and the roller 14 is in contact with the peripheral surface of the X-axis plate cam 4. The driven arm 13 includes an arm 13
A linear guide rail 15 (FIG. 3) is fixed to the side closer to the fulcrum shaft s1 from the distal end in the longitudinal direction, and a linear guide block 16 is slidably attached thereto. In FIG. 1, the X-axis lever 11 is at the retreat end (right end) of the reciprocating rotation, and the roller 14 is located at the position where the distance from the center of the cam drive shaft 10 is the smallest in the X-axis plate cam 4. The side arm 13 is substantially vertical.

Reference numeral 17 denotes a Z-axis lever (FIG. 1,
4), the rear end is rotatably attached to the same fulcrum shaft s1 as the X-axis lever 11, and the roller 18 is attached to the intermediate portion, and this portion is used as a cam follower contacting the peripheral surface of the Z-axis plate cam 5,
Further, a roller 19 is attached to the front end, and the Z-axis lever 1 is mounted.
7 as the driven side. In FIG. 1, the Z-axis lever 17
Is at the upper end of the vertical reciprocation. Since this embodiment is intended to show that the stroke in the X-axis direction can be adjusted, the Z-axis slide mechanism is simply shown in the drawing, and the movement in the Z-axis direction is fixed to the upper end position in the drawing. .

The base end of the variable stroke guide 20 is rotatably supported on the base plate 2 about a fulcrum shaft s2 (FIGS. 3 and 5). Therefore, the stroke variable guide 20 can change the angle of the guide axis a (a1-a1, a2-a2) by rotating the tip about the fulcrum axis s2. Although there are various mechanisms for the change, in this embodiment (FIGS. 5 and 6), the base plate 2 on the rear side is used.
a screw fixing block 21 and nut block 22 inside
, And the adjusting screw 23 is vertically passed through them, and the adjusting block 24 is attached to the lower end thereof, so that the adjusting screw 23 can be rotated. The adjustment block 24 is fitted in a vertically long guide slot 25 (FIG. 5) provided in the base plate 2a in a concave shape facing inward as a whole, and can be moved vertically. The adjustment block 24 holds an intermediate portion of the variable stroke guide 20 inside.

The gripping mode is the stroke variable guide 20.
Is pushed up from below by a preset spring 26, and the upper surface of the variable stroke guide 20 is abutted against the lower end of the adjusting screw 23 to be sandwiched. A plate washer 27 is applied to the outer surface of the guide slot 25, and a fixing screw 28 is inserted into the adjustment block 24 from above, and the stroke variable guide 20 is fixed to the base plate 2a. The upper end of the adjusting screw 23 is formed in a spanner hook 29 and is arranged so as to protrude from the upper side of the base plate 2a. That is, the inclination of the variable stroke guide 20 releases the restraint of the adjusting screw 23 by the screw fixing block 21, loosens the fixing screw 28, and uses the spanner hook 9 to move the adjusting screw 23 to the nut block 22. The rotation is performed by turning. By the rotation of the adjustment screw 23, the inclination of the stroke variable guide 20 together with the adjustment block 24 changes about the fulcrum axis S2. After setting the inclination, the screw fixing block 21 is tightened to restrain the rotation of the adjusting screw 23, and the fixing screw 28 is tightened to fix the inclination of the stroke variable guide 20. The angle range between the guide axes a1-a1 and a2-a2 shown in FIG. 3 is a range that can be adjusted.

The variable-stroke guide 20 is a groove-shaped guide, and a follower roller 30 (having its center at the axis point s) provided on the linear guide block 16 of the X-axis lever 11.
3) are engaged. When the driven arm 13 of the X-axis lever 11 is at the retracted end, the follower roller 30 is at the same position as the fulcrum shaft s2 of the variable stroke guide 20 (FIG. 3). That is, the variable stroke guide 2
The fulcrum shaft s2 of 0 is located on the lower right side of the driven arm 13 when the X-axis lever 11 is at the retracted end, and the guide axis a (a1-a1 or a2-a2) is the lever axis bb of the linear guide. And the horizontal direction intersects.

Reference numeral 31 denotes an X arm, which is guided by an X-axis guide 32 and can move in the left-right direction. X arm 31
At the rear end, a vertical end plate 33 is fixed,
A pressing roller 34 further provided on the linear guide block 16 is in contact with the linear guide block 16 (FIGS. 1 and 4). The pressing roller 34 is arranged coaxially with the follower roller 30. Therefore, the position of the pressing roller 34 always coincides with the position of the follower roller 30.

Between the X-axis guide 32 and the X arm 31, a coil spring 35 for constantly pressing the X arm 31 backward is attached. The X-axis guide 32 is fixed to the lower end of the Z-arm 36, and moves up and down as the Z-arm 36 moves up and down by rotation of the Z-axis plate cam 5. The vertical movement of the X arm 31 by the Z-axis plate cam 5 and the left and right movement by the X-axis plate cam 4 are controlled by these plate cams 4,
The rotation of 5, which is performed at a predetermined timing, causes the chuck of the top plate attached to the tip of the X arm 31 to perform a pick-and-place portal movement or L-shaped movement.

The operation of the X arm 31 in the X axis direction will be described. Now, as shown in FIG. 3, the rotational position of the X-axis plate cam 4 is at the retreat end position where the distance from the cam drive shaft 10 is the shortest, and the stroke variable guide 20 is positioned on the axis a1-a1 with the front end upward. Position (FIG. 3). The X arm 31 is pushed by the coil spring 35 and the end plate 33 is in contact with the pressing roller 34 of the linear guide block 16 provided on the driven arm 13 of the X-axis lever 11. Since it is the retreat end position, the pressing roller 34 provided on the linear guide block 16 and the stroke variable guide 2
The axial point s3 of the follower roller 30 engaged with the groove of No. 0 is
It corresponds to the fulcrum axis s2 of the stroke variable guide 20.

When the X-axis plate cam 4 is rotated by the drive motor 6, the X-axis lever 11 rotates clockwise about the fulcrum shaft s1 to move the driven arm 13 forward. Along with this, the follower roller 30 of the linear guide block 16 in the driven arm 13 moves along the guide axis a1-a1 and at the same time along the rail axis bb. In this case, it moves forward and upward as a whole. . By this operation, the pressing roller 34 provided on the linear guide block 16 moves forward and upward, and the end plate 3
3, the X-arm 31 is pushed forward while the coil spring 35 is compressed. Since the X arm 31 is guided by the X axis guide 32 on the Z axis side, it moves horizontally,
The linear guide block 16 has a variable stroke guide 20.
The guide axis a1-a1 is moved forward and upward. That is, the pressing roller 34 presses the X-axis slider 31 forward while rolling above the end plate 33.

When the X-axis plate cam 4 rotates about 120 °, the roller 14 of the drive arm 12 of the X-axis lever 11 reaches the position where the distance from the cam drive shaft 10 is the longest. Block 16
Reaches the forward end position (FIGS. 7 and 8). The X-axis arm 31 also reaches the forward end position. At this time, the amount of movement (the horizontal linear distance) from the retracted end is the horizontal distance L1 between the fulcrum axis s2 and the axis point s3 of the follower roller 30. According to this embodiment, the cam peripheral surface structure of the X-axis plate cam 4 has a long portion where the distance from the cam drive shaft 10 is equal,
The period during which the arm 31 remains at the forward end or the backward end is relatively long. In each of the periods, the rotation angle of the X-axis plate cam 4 is about 120 °.

Next, the operation when the angle of the variable stroke guide 20 is adjusted will be described. In FIG.
The adjusting screw 23 is turned by loosening the fixing screw 28 and the screw fixing block 21, and the adjusting block 24 is pushed down. Thereby, the front end of the variable stroke guide 20 is rotated downward about the fulcrum shaft s2 in FIG. 2 and fixed at the position of the axis a2. The variable stroke guide 20 is inclined forward and downward from the fulcrum shaft s2.

When the X-axis plate cam 4 rotates in this state, the X-axis lever 11 rotates about the fulcrum shaft s1 in the same manner as described above, and assumes the front end position shown in FIGS. However, at this time, the follower roller 30 of the linear guide block 16
Is moved to near the tip of the linear guide rail 15 in the X-axis lever 10, so that at the forward end position, the horizontal distance L2 between the fulcrum axis s2 and the axis point s3 of the follower roller 30 is the horizontal distance It is clearly larger than L1. That is, by changing the angle of the stroke variable guide 20 from the axis a1-a1 to the axis a2-a2, the stroke of the X-axis slider 31 could be increased by the difference between L2 and L1.

Here, assuming that the angles of the axes a1-a1 and a2-a2 are the maximum and minimum of the angles that the stroke variable guide 20 can take, the stroke of the X arm 31 is set between the angles of the axes a1-a1 and a2-a2. It can be adjusted arbitrarily. Thus, the stroke of the X arm 31 can be easily and manually adjusted.

The above description is based on the assumption that the retreat end is a fixed point and X
The stroke was adjusted by changing the forward end of the arm 31. However, by changing the position of the fulcrum shaft s2 that supports the variable stroke guide 20 to the base plates 2a and 2b, or by changing the shape of the X-axis lever 11, It is also possible to adopt a structure in which the forward end is a fixed point and the backward end is adjusted.
Similarly, the Z-axis slide mechanism can have a structure capable of adjusting the stroke. Further, by manually adjusting the angle of the variable stroke guide 20 using a servo motor or a stepping motor, the robot can be used to discharge the workpiece to a pallet where the supply position is changed each time, or to supply one part at multiple points. It can also be used for systems that are used. In the above description, terms having directions such as up and down, left and right, distal end, and proximal end are defined for convenience of explanation, and are actually relative terms that vary depending on the use state of the PPU 1.

[0026]

According to the present invention, in a PPU having a main structure including a cam, a lever, and an X arm, a stroke can be easily adjusted without changing parts, so that it is possible to easily cope with a change in a work size and a change in a work position. PPU that can be used. Since the structure for adjusting the stroke is simple, the durability is high, and the number of parts is small, the position repeatability is high and the cost can be reduced. Since the main structure is a structure including a cam, a lever, and an X-arm, a compact PPU with a short cycle time and reliable operation can be obtained.

[Brief description of the drawings]

FIG. 1 is a front view schematically showing a mechanism.

FIG. 2 is a side view of a partial cross-section showing a plate cam and its drive system.

FIG. 3 is a front view for explaining a variable stroke mechanism.

FIG. 4 is a partial cross-sectional side view for explaining a structure related to the linear guide block.

FIG. 5 is a front view showing an adjustment structure of a variable stroke guide.

FIG. 6 is a partial cross-sectional side view for explaining an adjustment structure of a variable stroke guide.

FIG. 7 is a front view showing a state where the X-axis slider is at a forward end position when the stroke is small.

FIG. 8 is a front view of the variable stroke mechanism when the stroke is set to be small (forward end position).

FIG. 9 is a front view showing a state where the X-axis slider is at a forward end position when the stroke is large.

FIG. 10 is a front view of the variable stroke mechanism when the stroke is set to be large (forward end position).

[Explanation of symbols]

 Reference Signs List 1 PPU 2a, 2b Base plate 3 Substrate 4 X-axis plate cam 5 Z-axis plate cam 6 Drive motor 7 Output shaft 8a, 8b Gear 9 Gear 10 Cam drive shaft 11 X-axis lever 12 Drive arm 13 Follower arm 14 Roller 15 Linear Guide rail 16 Linear guide block 17 Z-axis lever 18 Roller 19 Roller 20 Variable stroke guide 21 Screw fixing block 22 Nut block 23 Adjustment screw 24 Adjustment block 25 Guide slot 26 Preset spring 27 Plate washer 28 Fixing screw 29 Spanner hook Reference Signs List 30 Follower roller 31 X arm 32 X axis guide 33 End plate 34 Press roller 35 Coil spring 36 Z arm a1-a1, a2-a2 Guide axis s1 Support axis (X-axis lever) s2 Support axis (straw) Variable guide) s3 axis point (follower roller)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) F16H 25/16 F16H 25/16 A

Claims (3)

[Claims] 1. A cam, a linearly moving X arm, a rotary lever having a drive side arm for the cam and a driven side arm for the X arm, and a stroke variable guide,
A pick-and-place device having a mechanism for transmitting a displacement of the drive-side arm due to rotation of a cam to an X-arm at the other end of a driven side arm of a lever, wherein the variable stroke guide is configured such that the distal end is more driven side than the base end in the lever. The guide axis, which is the guide direction, is defined as X inside the rotation locus of the arm.
The arm is inclined with respect to the direction of linear movement of the arm, and a connection point between the other end of the driven arm and the X arm can be moved along the guide axis of the variable stroke guide simultaneously with the longitudinal direction of the driven arm. Pick and place device characterized by the following. 2. A pick-and-place device having a mechanism for moving a top plate at the tip of an X arm to the left and right by rotation of a cam, wherein the X arm is slidable in the left and right direction parallel to a surface of the base plate. A cam that is supported by a motor and rotates by a motor, a lever that rotates left and right parallel to the surface of the base plate around a fulcrum shaft that is supported by the base plate, and a lever that rotates in a plane parallel to the base plate around a fulcrum shaft at the base end A variable stroke guide that moves, the variable stroke guide is rotated around the fulcrum shaft and fixed, thereby enabling selection of an inclination angle of a guide axis indicating a guide direction, and moving the guide axis with the lever. And is disposed so as to intersect a lever axis along the longitudinal direction of the driven arm at A linear guide rail along the lever axis, and a linear guide block mounted on the linear guide block so that it can move up and down. In addition to being movably connected, the variable stroke guide and the linear guide block are rotatable,
And a pick-and-place device which is movably connected along the guide axis. 3. A Z-arm mechanism for moving the X-arm in the Z-axis direction, wherein a top plate provided at the tip of the X-arm is operated by a combination of movements in the X- and Z-directions. 3. The pick and place device according to 2.