JP4702587B2 - Grip device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a grip device for gripping an article, and more particularly to a grip device configured to be able to expand and contract an interval between grip members.
[0002]
[Prior art]
As the above-described gripping device, a pair of movable blocks that are arranged opposite to each other and to which a grip member is swingably attached, a guide that guides these movable blocks in a direction of expanding and contracting, and a penetrating through the grip member respectively. And a pair of oscillating rods extending along the guide and a driving means connected to the ends of the oscillating rods to open and close the grip member by oscillating the oscillating rods. (Japanese Examined Patent Publication No. 58-7434).
[0003]
[Problems to be solved by the invention]
In the conventional grip device described above, when the position of the movable block is changed in order to adjust the interval between the grip members, the opening / closing stroke of the grip member varies. That is, the opening / closing stroke of the grip member increases as the grip member approaches the tip from the end of the swing rod.
As a result, when the grip device is used in combination with a belt conveyor as a conveying means for conveying an article, there are the following drawbacks. That is, if the gap between the grip members is changed in order to match the size of the article to be changed, the opening / closing stroke of the grip member changes as described above. It is necessary to change the conveyance interval of the article so that it does not interfere with the article. In particular, the conveyance interval has to be increased as the article becomes smaller.
Under such circumstances, there has been a problem that the article supply interval per unit time cannot be increased by narrowing the article conveyance interval as much as possible, and the improvement of the processing capacity is hindered.
In addition, even when an article conveyed in a random state is recognized by a camera and gripped, there is a problem that a sufficient interval between the articles is required and processing capacity is reduced.
In view of the above-described circumstances, the present invention provides a grip device in which an opening / closing stroke is maintained constant even when the interval between grip members is increased or decreased.
[0004]
[Means for Solving the Problems]
That is, a plurality of grip members provided so as to be swingable, an opening / closing mechanism that swings and opens these grip members, and an interval adjustment mechanism that expands / contracts the interval between the grip members according to the article to be gripped are provided. In the grip device,
The distance adjusting mechanism includes a pair of first movable blocks and a pair of second movable blocks, each of which is attached to each of the grip members so as to be swingable. It comprises a guide for guiding, the pair of first movable blocks can be moved independently in the left-right direction, and the pair of second movable blocks can be moved independently in the front-rear direction ,
The opening / closing mechanism includes a driven portion provided in each grip member, a driving member having a driving portion that interlocks each driven portion, and a forward and backward movement of the driving member via the driving portion and the driven portion. Drive means for opening and closing each grip member, and the drive portion extends in the longitudinal direction of the guide, whereby the follower portion of each grip member moves the movable block along the guide. Maintain the linkage with the drive unit,
Furthermore, it has fixing means for positioning and fixing each movable block at an arbitrary position on the guide . The fixing means includes a pressure receiving portion provided in each movable block, and a pressure contact member having a pressure contact portion pressed against the pressure receiving portion. And the pressure contact portion extends in the longitudinal direction of the guide, so that the pressure receiving portion of each movable block can be pressed by the pressure contact portion when the movable block is moved along the guide. It is characterized by that.
[0005]
According to the grip device described above, since the drive portion of the drive member extends in the longitudinal direction of the guide, when the grip members are moved along the guide according to the article to be gripped, In addition, since the forward / backward movement of the drive member by the drive means is applied uniformly over the entire length of the drive unit, the opening / closing stroke of the grip member is kept constant regardless of the position of the grip member.
In addition, the pair of first movable blocks can be moved independently in the left-right direction, and the pair of second movable blocks can be moved independently in the front-rear direction . The article can be securely gripped from the front, rear, left and right.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below with reference to the illustrated embodiments. In FIGS. 1 and 2, reference numeral 1 denotes a grip device for gripping an article, and the grip device 1 swings each grip member 2 provided so as to be swingable. An opening / closing mechanism that opens and closes, and an interval adjustment mechanism that expands / contracts the interval between the grip members 2 according to the article to be held. The grip device 1 is attached to a head 99 of a robot (not shown). It is applied to a caser or the like that grips and transfers a cake pan C for makeup as an article that is moved by being moved and aligned and conveyed on a belt conveyor (not shown).
The grip device 1 includes a buffer mechanism 5 at the top thereof. The shock absorbing mechanism 5 includes a bottomed cylindrical inner member 6 having a cylindrical portion 6B that is connected to the head 99 of the robot and having an upper end surface 6A extending downward from the upper end surface 6A, and the inner member 6. A cylindrical outer member 7 with a bottom having a lower end surface 7A for slidably fitting the cylindrical portion 7B to the outer periphery of the cylindrical portion 6B and closing the lower side of the cylindrical portion 7B, and the inner member 6 and a coil spring 10 which is elastically mounted between the upper end surface 6A of the outer member 7 and the lower end surface 7A of the outer member 7. The coil spring 10 biases the inner member 6 and the outer member 7 away from each other. Thus, the locking surface 7C constricting the upper inner periphery of the cylindrical portion 7B and the engaging surface 6C constricting the upper outer periphery of the cylindrical portion 6B are maintained in a normal state.
Thereby, when the grip device 1 is lowered, even if the grip member 2 provided at the lower end of the grip device 1 comes into contact with the belt conveyor, the outer member 7 becomes the inner member by the compression of the coil spring 10. 6 and the head 99, the grip member 2 is prevented from being damaged or deformed.
Further, the outer member 7 is provided with an engaging pin 9 whose end is embedded in the cylindrical portion 7B and whose tip is inserted into a slit 6D provided in the cylindrical portion 6B of the inner member 6. The engaging pin 9 prevents the outer member 7 from rotating with respect to the inner member 6.
[0007]
A disk-shaped fixed frame 14 is attached to a lower end surface 7A of the outer member 7 of the buffer mechanism 5 by a plurality of rods 13 via an air cylinder 30 and a plurality of spacers 30A (rods 13, spacers 30A). Is only one). Flat plate-like support plates 15 that extend downward in the vertical direction by screws 12 are provided at four locations in the circumferentially equidistant position of the outer peripheral portion of the fixed frame 14, and only the left and right two locations are shown in FIG. 1. The two support plates 15 shown on the front side and the rear side are not shown.
A center rod 16 extending vertically downward is provided at the center position of the fixed frame 14, and a prismatic support block 17 is attached to the lower end thereof. The support block 17 is set so that each surface thereof faces the support plate 15 in parallel.
In addition, a pair of support plates 15 arranged to face each other in FIG. 1 are provided with a single continuous first guide rod 18A that extends through the support block 17 in the horizontal direction. A pair of support plates (not shown) arranged so as to face each other pass through the support block 17 at a position higher than the first guide rod 18A and are orthogonal to the first guide rod 18A. One continuous second guide rod 18B extending in the direction is provided.
A pair of first screw shafts 19 </ b> A extending through the pair of support plates 15 facing the left and right and extending in the horizontal direction with their tips pivotally supported by the support block 17. A pair of support plates (not shown) provided so as to be rotatable in a front-rear direction pass through the support plates (not shown) at a position higher than the first screw shaft 19A, and the tips of the support plates 17 are supported. A pair of second screw shafts 19B (only the shaft support portion is shown) that are respectively supported by the shafts and extend in the horizontal direction perpendicular to the first screw shaft 19A are rotatably supported. A large-diameter knob 19A ′ (only the first screw shaft 19A is shown) is connected to the ends of the shaft 19A and the second screw shaft 19B.
And between each said support plate 15 and the support block 17 located in the center, it penetrates by said 1st guide rod 18A, is supported by this, and is screwed together with said 1st screw shaft 19A. While a pair of first movable blocks 20A are disposed, the pair of second movable rods 20B are passed through and supported by the second guide rod 18B and screwed to the second screw shaft 19B. A movable block 20B (shown in FIG. 2) is disposed, and the first movable block 20A and the second movable block 20B are aligned at the same height position. The grip member 2 is swingably attached to the movable blocks 20A and 20B.
Thereby, for example, if the first screw shaft 19A is rotated forward and backward via the left and right knobs 19A ', the left and right first movable blocks 20A screwed to the first screw shaft 19A are connected to the first screw shaft 19A and the first screw shaft 19A. It can be moved in the direction of expansion / contraction along the guide rod 18A, and if the second screw shaft 19B is rotated forward / reversely via front / rear knobs (not shown), The second movable block 20B can be moved in the direction of expansion / contraction along the second screw shaft 19B and the second guide rod 18B.
The guide rods 18A and 18B and the screw shafts 19A and 19B constitute a guide for guiding the distance between the movable blocks 20A and 20B in the direction of expanding and contracting, and the guide and the movable blocks 20A and 20B constitute a distance adjusting mechanism. ing. In addition, as a structure of a guide, you may make it provide either one of guide rod 18A, 18B or screw shaft 19A, 19B.
[0008]
The movable blocks 20A and 20B and the grip members 2 provided on the front, rear, left and right respectively have substantially the same configuration, so the configuration of the right movable block 20A and the grip member 2 shown in FIG.
The grip member 2 that is swingably attached to the movable block 20A includes a substantially L-shaped swing member 25, a plate member 26 that comes into contact with an article to be gripped, and an attachment member 24 to which the plate member 26 is attached. It is composed of
On the upper side of the movable block 20A, a pair of plate-like support portions 20a are provided on both sides in parallel with the longitudinal direction of the guide rod 18A. A pin 27 spanned between the support portions 20a is generally L By penetrating through the corner of the rocking member 25 having a letter shape, the rocking member 25 is swingably supported with the penetrating position of the pin 27 as a fulcrum. The swing member 25 is arranged in an inverted L shape, and its short side is a driven part 25A and is extended toward the center side where the support block 17 is arranged, and a cam roller 28 can be rotated at the tip thereof. I have. On the other hand, on the long side, the guide rod 18A and the screw shaft 19A are allowed to oscillate so that the oscillating member 25 can oscillate, and the lower side extends downward. Standing up. The mounting member 24 is provided with a plate spring 35 whose upper end is brought into contact with the side surface of the movable block 20A on the inner side (center side where the support block 17 is disposed), and is overlapped with the plate member 35. 26 is attached facing downward. As a result, the leaf spring 35 biases the grip member 2 in the closing direction, and holds the article by the elastic force of the leaf spring 35 as will be described in detail later.
[0009]
A screw member 21 is provided at a predetermined position of the center rod 16 fixed to the fixed frame 14 so as to be freely rotatable with its vertical position regulated. The screw member 21 includes a disc-shaped dial portion 21A and a screw portion 21B that is provided on the lower end surface of the dial portion 21A and extends downward. The screw portion 21B includes a guide rod 18A, The center portion of the pressure contact member 22 extending in a cross shape along the longitudinal direction of 18B and the screw shafts 19A and 19B is screwed.
The pressure contact member 22 is formed in a U-shaped cross section having a cross-shaped upper surface portion 22c and side surface portions 22d suspended from both sides thereof, thereby forming a cross-shaped concave portion 22B. The width of the opposing side surface portion 22d is equal to the width of the pair of support portions 20a provided upright on the movable blocks 20A and 20B, the lower end surface of the side surface portion 22d is the pressure contact portion 22A, and the upper end surface of each support portion 20a is the pressure receiving portion. As 20b, the pressure contact member 22 is disposed above the movable blocks 20A and 20B, and the pressure contact member 22 is lowered so that the pressure contact portion 22A is in pressure contact with the pressure receiving portion 20b.
Accordingly, by rotating the screw member 21 forward and backward via the dial portion 21A, the pressure contact member 22 screwed into the screw portion 21B of the screw member 21 can be moved up and down, and the pressure contact member In a state where the pressure contact portion 22A of 22 is separated from the pressure receiving portion 20b of the movable blocks 20A and 20B, the movable blocks 20A and 20B can be expanded and contracted along the guide rods 18A and 18B and the screw shafts 19A and 19B. When the portion 22A is in pressure contact with the pressure receiving portion 20b of the movable blocks 20A and 20B, the movable blocks 20A and 20B can be restrained. That is, the pressure receiving member 20b of the movable blocks 20A and 20B and the pressure contact member 22 having the pressure contact portion 22A constitute fixing means for maintaining the first and second movable blocks 20A and 20B in an arbitrary expansion / contraction state. .
[0010]
An air cylinder 30 as a driving means connected to a fluid supply source (not shown) is attached to the lower end surface 7A of the outer member 7 constituting the buffer mechanism 5, and a piston rod 29 of the air cylinder 30 is Directed downward in the vertical direction. A disc-shaped lifting frame 32 is connected to the tip of the piston rod 29 by screws 31. A nut 16A for fixing the center rod 16 protrudes from the upper surface of the fixed frame 14, and the elevating frame 32 is controlled to be lowered by coming into contact therewith.
Four rods 33 (only two are shown in the figure) are mounted at four positions at equal circumferential positions of the elevating frame 32 so as to pass through the fixed frame 14 and extend vertically downward. The center rod 16 is loosely fitted and penetrated at the lower end thereof, and a cruciform drive member 34 accommodated in the recess 22B of the press contact member 22 is integrally connected, and the lower surface thereof serves as a drive portion 34A. .
In this embodiment, regardless of the positions of the first and second movable blocks 20A and 20B, the drive portion 34A is maintained in order to maintain the interlocking between the drive portion 34A and the driven portion 25a of the grip member 2 in contact with the drive portion 34A. Are extended in the longitudinal direction of the guide rods 18A and 18B and the screw shafts 19A and 19B, and are formed in parallel therewith.
As a result, the forward and backward movement of the drive member 34 is uniformly applied over the entire length of the drive unit 34A. Therefore, when the drive member 34 is moved back to the rising end position by the air cylinder 30, the drive unit 34A. In response to the elastic force of the leaf spring 35, the driven portions 25a are pushed upwards all at once around the pin 27. In this state, the grip members 2 are simultaneously closed in the same stroke and are in a closed state. Become. On the other hand, when the drive member 34 is advanced to the lower end position, the driven portion 25a that is interlocked with the drive portion 34A is pressed downwards around the pin 27 against the leaf spring 35, In this state, the grip members 2 are simultaneously released with the same stroke to be in an open state. In other words, the drive member 34 having the driven portion 25A and the drive portion 34A of the swing member 25 and the air cylinder 30 constitute an opening / closing mechanism that opens and closes the grip members 2 simultaneously with the same stroke.
[0011]
The operation of the grip device 1 related to the above configuration will be described.
When gripping the square cake pan C shown by the imaginary line in FIG. 3, first, the interval between the grip members 2 is adjusted by the interval adjusting mechanism. At the time of adjusting the interval, the screw member 21 is rotated to raise the pressure contact member 22 so that the pressure contact portion 22A can be released from the pressure contact portion 20b and the first and second movable blocks 20A and 20B can be expanded and contracted. To do. When this expansion and contraction is possible, the first and second screw shafts 19A and 19B are rotated via the left and right knobs 19A 'and the front and rear knobs so that four grips are respectively provided from the support block 17 to positions at equal intervals. The member 2 is moved. At this time, the grip member 2 sets the position so that each plate member 26 contacts the side surface of the cake plate C during the closing operation in order to grip the cake plate C by the elastic force of the leaf spring 35. When the position adjustment is completed for all four movable blocks 20A and 20B, the screw shaft 21 is rotated to lower the pressure contact member 22 so that the pressure contact portions 22A are simultaneously brought into pressure contact with the pressure receiving portion 20A. As a result, the positions of the first and second movable blocks 20A and 20B are fixed.
When such advance adjustment work is completed, the transfer work of the cake dish C by the operation of the robot is started.
When the square cake pan C is conveyed by the belt conveyor and reaches a predetermined gripping position, the grip device 1 is moved to the predetermined gripping position, and the air cylinder 30 is operated to lower the drive member 34. Advance to the end. As a result, the driven portion 25a interlocked with the drive portion 34A of the drive member 34 is pressed downward all at once around the pin 27 against the leaf spring 35, so that each grip member 2 has the same stroke all at once. Released.
When the cake pan C is positioned between the gripper members 2 in this state, the air cylinder 30 is operated to immediately retract the drive member 34 to the rising end. As a result, the driven portions 25a are pushed up together around the pin 27 by the elastic force of the leaf spring 35 in conjunction with the drive portion 34A of the drive member 34, so that the grip members 2 are closed simultaneously. Then, the cake dish C is gripped. The robot holding the cake dish C moves the cake dish C to a predetermined release position, and operates the air cylinder 30 at this release position to advance the drive member 34 to the lowermost end, thereby moving the grip member. Release 2 to release cake pan C. Then, the robot that has released the cake dish C shifts to the processing operation for the next cake dish C.
[0012]
Next, when the triangular cake pan C shown by a solid line in FIG. 3 is gripped, the interval between the grip members 2 is adjusted in advance as described above. In this case, since the article to be gripped is a triangle, the pair of grip members 2 facing each other is arranged at an equal distance from the center where the support member 17 is located, but the other pair of grip members 2 facing each other is from the center. Are arranged asymmetrically with different distances. Thus, the arrangement of the grip members 2 can be freely set according to the shape of the article to be gripped. When such advance adjustment work is completed, the transfer work of the cake pan C is started in the same manner as described above.
[0013]
As understood from the above description, according to the grip device 1, the drive portion 34A of the drive member 34 extends in the longitudinal direction of the guide (guide rods 18A, 18B or screw members 19A, 19B). Even when the grip members 2 are moved in accordance with the article to be gripped (cake pan C) and the interval is enlarged or reduced, the forward / backward movement of the drive member 34 by the drive means (air cylinder 30) extends over the entire length of the drive unit 34A. Therefore, the opening / closing stroke is kept constant regardless of the position of the grip member 2.
[0015]
In the above embodiment, the grip member 2 is biased by the leaf spring 35 in the closing direction. However, the grip member 2 is not limited to this and may be biased in the releasing direction or the driving member 34. A cam groove extending along the guide may be formed on the side surface of the plate, and the drive portion and the driven portion may be interlocked by engaging the cam roller of the grip member in the cam groove. The spring may be omitted.
[0016]
【The invention's effect】
According to the present invention as described above, Ki out to maintain the opening and closing stroke of the no gripping members related to the position of the gripping member in constant and respectively securely grip the square shape of the article or triangular article from all directions The effect that it can do is acquired.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a grip device 1 showing an embodiment of the present invention.
FIG. 2 is a perspective view of a driven portion 25A and a drive member 34 that constitute an opening / closing mechanism, and a pressure receiving portion 20b and a pressure contact member 22 that constitute a fixing means.
FIG. 3 is a view for explaining an interval between grip members 2 (26) according to the shape of a cake pan C.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Grip apparatus 2 ... Grip member 18A, 18B ... Guide rod 19A, 19B ... Screw shaft 20A, 20B ... Movable block 20b ... Pressure receiving part 22 ... Pressure contact member 22A ... Pressure contact part 23 ... Fixing means 25 ... Swing member 25A ... Follower Part 28: Cam roller 30 ... Air cylinder 34 ... Drive member 34A ... Drive part C ... Cake dish

Claims (1)

A grip device including a plurality of grip members provided so as to be swingable, an opening / closing mechanism that swings and opens the grip members, and a distance adjusting mechanism that expands / contracts the distance between the grip members according to an article to be gripped. In
The distance adjusting mechanism includes a pair of first movable blocks and a pair of second movable blocks, each of which is attached to each of the grip members so as to be swingable. It comprises a guide for guiding, the pair of first movable blocks can be moved independently in the left-right direction, and the pair of second movable blocks can be moved independently in the front-rear direction ,
The opening / closing mechanism includes a driven portion provided in each grip member, a driving member having a driving portion that interlocks each driven portion, and a forward and backward movement of the driving member via the driving portion and the driven portion. Drive means for opening and closing each grip member, and the drive portion extends in the longitudinal direction of the guide, whereby the follower portion of each grip member moves the movable block along the guide. Maintain the linkage with the drive unit,
Furthermore, it has fixing means for positioning and fixing each movable block at an arbitrary position on the guide . The fixing means includes a pressure receiving portion provided in each movable block, and a pressure contact member having a pressure contact portion pressed against the pressure receiving portion. And the pressure contact portion extends in the longitudinal direction of the guide, so that the pressure receiving portion of each movable block can be pressed by the pressure contact portion when the movable block is moved along the guide. A grip device characterized by that.

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