JPH0644587Y2 - Gripping device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a gripping device, and more specifically, grips a work, for example, the cylinder block by expanding the diameter in a hole formed in the cylinder block. The holding means is attached to a bracket that is movable back and forth so as to be movable in a direction orthogonal to the axial direction of the hole, and even if a displacement occurs between the holding means and the cylinder block, the holding means itself is attached to the bracket. The present invention relates to a gripping device that can be individually displaced to reliably grip the cylinder block.

[Background of the Invention] In general, a line production system for automatically performing various operations has been widely adopted in a factory. For example, a work such as a cylinder block that constitutes an engine is cast and formed by a die casting machine or the like, and then is conveyed to a processing station to be stretched.
Next, the work is conveyed to the heat treatment station via the conveying means and positioned and placed on a predetermined pallet. After that, the pallet is carried into a heat treatment furnace to heat-treat the work, further cooled, and then the work on the pallet is sent to the next work position. In this way, various processing operations for the work to be cast and molded such as the cylinder block are automatically performed.

By the way, in the above-mentioned heat treatment station, a gripping device is provided for automatically moving the work from the transfer means onto the pallet or from the pallet to another transfer means. At that time, the gripping device holds the cylinder block by engaging a holding portion with a predetermined portion of the work, for example, if the work is a cylinder block, a cylinder bore portion. Therefore, if the cylinder bore portion is displaced with respect to the holding means, the holding means may not be able to hold the cylinder block. Therefore, it has been pointed out that a special positioning device is required to accurately position the work with respect to the transporting means and the pallet, resulting in a high equipment cost.

Moreover, in a work such as a cylinder block which is cast-molded, the dimensional accuracy often varies from work to work, and even if each work is accurately positioned, a predetermined portion of this work can be reliably held against the gripping means. It is not always possible to position it at. As a result, a defect that the gripping defect of the work is easily caused becomes apparent.

[Object of the Invention] The present invention has been made in order to overcome the above-mentioned inconvenience, and provides a holding means for holding the work by inserting it into a hole formed in the work and expanding the diameter of the work. After that, the holding means is attached to a bracket that is movable back and forth so as to be movable in a direction substantially orthogonal to the axial direction of the hole, and the bracket is displaced with respect to the work to insert the holding means into the hole of the work. When this is expanded and the inner wall surface of the hole is pressed, the holding means moves and becomes coaxial with the axis of the hole even if the holding means and the hole cause positional deviation. As a result, it is not necessary to position the work with high precision with respect to the transfer means, pallets, etc., and the equipment cost can be kept low, and the work can be securely gripped to perform automatic and efficient work processes. To do It is an object of the present invention to provide a gripping device that is made possible.

[Means for Achieving the Object] In order to achieve the above object, the present invention holds a work by holding a work by expanding a diameter in a hole formed in a work and pressing an inner wall surface of the hole. First attached to the body
And the second holding means, and the respective arcuate surfaces are brought into sliding contact with each other so that the first and second holding means
The first and second support plates that positionally support the holding means, the bracket that can advance and retreat with respect to the work, and the first and second holding means with the respective axial directions always maintained in the same direction. Guide means for movably supporting in a direction substantially orthogonal to the axial direction of the hole portion, the guide means being elastic interposed between the first and second support plates and the bracket. And a rotating body that is rotatably provided on the bracket and that movably mounts the plate body in various directions within a plane substantially orthogonal to the axial direction.

[Embodiment] Next, the gripping device according to the present invention will be described in detail below with reference to preferred embodiments, with reference to the accompanying drawings.

In FIG. 1, reference numeral 10 indicates an arm of a robot, and this arm 10 can be displaced along a predetermined locus under the action of a robot main body (not shown). A rotary drive source 12 is fixed to the tip of the arm 10.
The gripping device 14 according to the present embodiment is rotatably attached to the arm 10 via.

That is, the gripping device 14 has a plate body 16 having an L-shaped cross section.
A rotary drive shaft (not shown) extending from the rotary drive source 12 is attached to one end of the plate body 16 and
A support member extending in the vertical direction on the other end side of 16
18 is retained. The support member 18 is formed with a pair of parallel guide rails 20a, 20b oriented in the vertical direction, and an opening 22 is formed at the lower side of the guide rails 20a, 20b, and the opening 22 is formed. The rotary drive source 24 is fixed to the lower part of the support member 18 that is close to the base and bulges in the horizontal direction. One end of a ball screw 26 is axially attached to a rotary drive shaft (not shown) of the rotary drive source 24 via a coupling 25, and the other end of the ball screw 26 is an upper portion of a support member 18 that bulges in the horizontal direction. It is rotatably supported by.

Then, an elevating table 28 is arranged on the supporting member 18. In this case, the lift base 28 is provided so as to be lifted up and down on the support member 18 so as to be sandwiched between the guide rails 20a and 20b, and a nut for fitting the ball screw 26 on the upper side of the lift base 28. The member 30 is attached. On the other hand, the lower side of the lift table 28 extends downward through the opening 22 of the support member 18, and the bracket portion 32 is formed on this lower side so as to project in the direction opposite to the lower direction of the support member 18. , Holding means on this bracket part 32
34 is installed.

That is, as shown in FIG. 2 and FIGS. 4A and 4B, the bracket portion 32 is provided with holes 36a, 36b spaced apart by a predetermined distance.
Are provided, and the guide members 38a to 38f are fixed so as to surround the hole portions 36a and 36b. The guide member 38a
Spheres 40a to 40f are rotatably provided on the spheres 38a to 38f, respectively, and the plate body 42 is movably mounted on the spheres 40a to 40f. Holders 44a and 44b are provided on the lower surface of the plate 42.
Are fixed at a predetermined distance, and in this case, the holder 44
a is a first cylindrical portion 46 that substantially fits in the hole portion 36a of the bracket portion 32, and a second cylinder having a diameter larger than that of the first cylindrical portion 46 and smaller than the diameter of the hole portion of the cylinder block described later. Part 48
Consists of. As shown in FIGS. 4A and 4B, a hole portion 50 having a diameter larger than that of the hole portion of the first cylindrical portion 46 is defined in the second cylindrical portion 48, and this hole portion 50 is formed in the second cylindrical portion 48. Of the four openings 52a to 5a formed on the outer peripheral surface of the sheet at predetermined angular intervals.
It is opened to the outside through 2d (see Fig. 2). Also, the second
Grooves 54a and 54b are formed on the outer peripheral surface of the cylindrical portion 48 in the circumferential direction.

Next, the cam pieces 56a to 56d are arranged in the hole 50 through the openings 52a to 52d of the second cylindrical portion 48. The cam pieces 56a to 5
The outer peripheral surfaces 58a to 58d of 6d are formed so as to correspond to the inner peripheral surface of the bore portion of the cylinder block, which will be described later.
To 58d, the groove portion 6 communicating with the groove portions 54a and 54b of the second cylindrical portion 48.
0a to 60d and 62a to 62d are engraved. Further, arcuate inclined surfaces 64a to 64d are formed on the inner surface side of the cam pieces 56a to 56d so as to define a tapered hole that gradually expands toward the direction away from the first cylindrical portion 46. The cam piece 56
The groove portions 60a to 60d of a to 56d, the groove portion 54a of the holder 44a, and the groove portions 62a to 62d of the cam pieces 56a to 56d and the holder 44.
Ring-shaped coil springs 65a, 6 in the groove 54b of a, respectively.
5b are fitted together (see Fig. 2). by this,
The cam pieces 56a to 56d are constantly pressed in the radial inward direction of the holder 44a.

Therefore, the conical cam 66 slides on the inclined surfaces 64a to 64d of the respective cam pieces 56a to 56d. That is, on the upper surface side of the plate body 42, the cylinder 6 is coaxial with the first cylindrical portion 46 forming the holder 44a.
The rod 70, to which 8 is fixed and extends vertically downward from the cylinder 68, is fitted in the first cylindrical portion 46. A conical cam 66 having the same tapered surface as the inclined surfaces 64a to 64d of the cam pieces 56a to 56d is integrally formed at the tip of the rod 70, and the tip of the conical cam 66 is gradually formed. A conical portion that reduces the diameter is provided.

The holder 44b has the same structure as the holder 44a described above, and the same constituent elements are designated by the same reference numerals and detailed description thereof will be omitted.

Next, the holders 44a and 44b are positioned and supported via the support plates 74a and 74b. The support plates 74a and 74b have respective holders.
Holes 76 for fitting the first cylindrical portions 46, 46 of 44a, 44b
A and 76b are bored, and circular arc surfaces 77a and 77b having the same radius formed at the ends of the respective support plates 74a and 74b are in sliding contact with each other. In this case, as shown in FIG.
locking members 78a fixed to both sides of a and the bracket portion 32,
Coil springs 80a and 80b are interposed between the coil springs 78b and 78b, and support plates are provided through the elastic force of the coil springs 80a and 80b.
74a is pressed to the support plate 74b side. On the other hand, the supporting members 74c and 78d provided on the bracket portion 32 are similarly provided on the support plate 74b.
And the coil spring 80 between both sides of the support plate 74b.
c and 80d are interposed, and the support plate 74b is pressed toward the support plate 74a side by the elastic force of the coil springs 80c and 80d.

The gripping device according to the present embodiment is basically configured as described above, and its operation and effect will be described next.

As shown in FIG. 1, a pallet 100 is disposed below the gripping device 14, and the pallet 100 is provided with positioning members 102a and 102b, which are paired and are shaped like a sword. Then, a plurality of workpieces, for example, cylinder blocks 104 are superposed in multiple stages via respective positioning members 102a and 102b. In this case, the cylinder block 104 has four holes 106 that define a cylinder bore.
a to 106d are formed, and the positioning members 102a and 102b are formed.
Fits into the outermost hole portions 106a and 106d to position each cylinder block 104, and the other hole portions 106a and 106d are positioned.
The holders 44a and 44b constituting the gripping device 14 are provided at b and 106c.
Through.

In this manner, the positioning members 102a and 102b are erected on the pallet 100, and the cylinder blocks 104 are mounted on the pallet 100 when the pallet 100 is moved by fitting and holding the cylinder blocks 104 on the respective positioning members 102a and 102b. It is possible to avoid inconveniences such as falling from the ground.

Next, the work of sending out the cylinder block 104 placed on the pallet 100 to a transport system (not shown) will be described in detail below.

First, the arm 10 is displaced in a predetermined direction under the driving action of a robot (not shown), and each holder 44 of the gripping device 14 is driven through the plate body 16 under the driving action of the rotary driving source 12.
The a and 44b are positioned with respect to the cylinder block 104 mounted on the pallet 100. Further, when the ball screw 26 is rotated in a predetermined direction via the coupling 25 under the driving action of the rotary drive source 24, the lifting table 28 is guided by the guide rails 20a and 20b via the nut member 30 engaging with the ball screw 26. Descend down. Therefore, the holders 44a and 44b mounted on the bracket portion 32 enter the holes 106b and 106c of the cylinder block 104 located at the uppermost position of the pallet 100.

At this time, if the conical cam 66 is displaced vertically downward in advance under the driving action of the cylinder 68, the cam pieces 56a to 56d slidingly contacting the conical cam 66 will have a radius via the elastic force of the coil springs 65a and 65b. It is displaced inward and its outer peripheral surfaces 58a to 58d are located substantially on the same plane as the outer peripheral surface of the second cylindrical portion 48. Therefore, the holders 44a and 44b are loosely fitted into the respective holes 106b and 106c (see FIG. 4a).

Therefore, the drive of the rotary drive source 24 is stopped and the cylinder
When the rod 70 is displaced vertically upward by driving the 68, the conical cam 66 integrally formed at the end of the rod 70 rises and the inclined surface of the conical cam 66 tilts the cam piece 56a within the 56d. surface
64a to 64d are pressed in the radial direction. Therefore, the cam piece 56
a to 56d are displaced outward in the radial direction against the elastic force of the coil springs 65a and 65b, and the outer peripheral surfaces of the respective cam pieces 56a to 56d.
58a to 58d come into pressure contact with the inner wall surface defining the hole portion 106b of the cylinder block 104 (see FIG. 4b). On the other hand, also in the holder 44b, similarly, the respective cam pieces 56a to 56a.
The diameter of 56d is expanded, and the outer peripheral surfaces 58a to 58d of the cam pieces 56a to 56d are pressed against the inner wall surface of the hole 106c of the cylinder block 104.

Next, when the rotation driving source 24 is driven to rotate the ball screw 26 in the opposite direction to the above, the lifting table 28 is displaced vertically upward through the nut member 30 with which the ball screw 26 is fitted. Therefore, the uppermost cylinder block 104 held by the respective holders 44a, 44b rises and the positioning members 102a, 102
When the arm 10 is separated from b, the arm 10 is displaced under the driving action of the rotary drive source 12 and a robot (not shown), and the cylinder block 104 held by the gripping device 14 is sent to a transport system (not shown).

At that time, when the cylinder 68 is driven to lower the rod 70, the conical cam 66 is displaced downward, and the cam pieces 56a to 56d are reduced in diameter by the elastic force of the coil springs 65a and 65b, so that the holder 44a. , 44b releases the holding action of the cylinder block 104. Therefore, when the rotary drive source 24 is driven to raise the bracket portion 32, the holders 44a and 44b are detached from the cylinder block 104, and then, as described above, they are respectively placed on the pallet 100. The transfer work of the cylinder block 104 may be performed.

In this case, according to the present embodiment, the cylinder block 104
Even if the cylinder block is not accurately positioned with respect to the pallet 100 or with respect to the transport means before being transferred to the pallet 100, the cylinder block is held through the gripping device 14.
104 can be held securely.

That is, as shown in FIG. 4A, for example, the hole 106b of the cylinder block 104 is displaced, and as described above, the gripping device 14 is lowered to move the holder 44a into the hole 106b. When inserted, the holder 44a and the hole 106b may not be coaxially located. In this state, when the cylinder 68 is driven to raise the conical cam 66 via the rod 70, the respective cam pieces 56a to 56d are concentrically expanded and displaced about the conical cam 66 to move inside the hole 106b. It just hits the wall.

However, in the gripping device 14, the holders 44a and 44b are fixed to the plate body 42, and the plate body 42 is mounted on the spheres 40a to 40f rotatably disposed on the bracket portion 32, and the holders are held. Coil springs 80a to 80d are engaged with support plates 74a and 74b holding 44a and 44b. Therefore, the holders 44a and 44b can be freely displaced in the horizontal direction with respect to the bracket portion 32. Therefore, as shown in FIG.
When the holder 44a is eccentrically and loosely fitted in the hole 106b of the cylinder block 104, the cam piece 56 is driven by the drive of the cylinder 68.
When a to 56d are displaced outward in the radial direction, first, the cam piece 56
The a contacts the inner wall surface defining the hole 106b. Further, when the cylinder 68 is driven to raise the conical cam 66, the cam piece 56a presses the inner wall surface via the outer peripheral surface 58a thereof, which causes the holder 44a to move in the arrow direction in FIG. 4a. Pressing force acts. Therefore, the support plate 74a that supports the holder 44a is pressed in the direction of the arrow, and the support plate 74b that is in sliding contact with the support plate 74a is integrated with the support plate 74a against the elastic force of the coil springs 80c and 80d. Move in the direction of the arrow.

As a result, when the holder 44a moves in the arrow direction and the conical cam 66 reaches the uppermost position under the action of the cylinder 68, the cam piece 56
The outer peripheral surfaces 58a to 58d of a to 56d are evenly pressed against the inner wall surface of the hole 106b to firmly press and hold the inner wall surface (see FIG. 4b).

Moreover, the plate body 42 that holds the holders 44a and 44b is mounted on the spheres 40a to 40f that are rotatably supported by the bracket portion 32. Therefore, an external force is applied to the holders 44a and 44b,
That is, when a pressing force is applied by the inner wall surfaces of the holes 106b and 106c, the plate body 42 can move extremely smoothly in various directions within the same plane. For this reason, the effect that the holders 44a and 44b can be easily and accurately coaxially moved with respect to the respective hole portions 106b and 106c and the cylinder block 104 can be reliably gripped becomes apparent.

[Advantages of the Invention] As described above, according to the present invention, the holding means for swelling the inside of the hole formed in the work and pressing the inner wall surface of the hole to hold the work is provided. The holding means is mounted on a bracket via an elastic body so as to be displaceable in a direction substantially orthogonal to the axis of the hole, and the bracket is configured to be movable back and forth with respect to the work. Therefore, even if the work is not positioned with high precision, when the holding means is inserted into the hole of the work and the diameter is expanded, the holding means itself moves and firmly presses the inner wall surface of the hole. Can hold. As a result, there is no need to provide a dedicated positioning device for positioning the work with high precision on the gripping device, and the effect that the equipment cost can be reduced at once is obtained. Further, the gripping device has a simple structure, and the gripping device itself can be economically obtained. Moreover, in particular, even in the case where the dimensional accuracy varies for each cast product such as the work obtained by casting, etc., the work is reliably gripped via the gripping device,
The substantial advantage that an efficient line process can be achieved also becomes apparent.

Although the present invention has been described with reference to the preferred embodiment, the present invention is not limited to this embodiment.
For example, a single support plate may be used in place of the two support plates into which the respective holders are fitted, and the holders may be held by pressing or pulling the support plates with a plurality of coil springs. It goes without saying that various improvements and design changes can be made without departing from the spirit of the invention.

[Brief description of drawings]

 FIG. 1 is a schematic perspective view of a gripping device according to the present invention, FIG. 2 is an enlarged perspective view with part of the gripping device omitted, and FIG. 3 is a bottom view of the gripping device with part omitted. [Fig. 6] is an operation explanatory view of the gripping device. 10 ... Arm, 14 ... Gripping device 24 ... Rotational drive source, 34 ... Holding means 44a, 44b ... Holder, 56a-56d ... Cam piece 66 ... Conical cam

Front page continuation (72) Takashi Nakajima 2-10-45 Sakaemachi, Asaka-shi, Saitama Prefecture (72) Kazuo Kuboshima 3-1-8 Misono-cho, Kodaira-shi, Tokyo (56) References: Practical reference 61-181617 (JP, U) Actually opened 60-109892 (JP, U) Actually opened 61-117693 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. A first and a second holding means for expanding a diameter of a hole formed in a work to press the inner wall surface of the hole to hold the work, and integrally attached to a plate. And the respective arcuate surfaces are brought into sliding contact with each other so that the first and second
The first and second support plates that positionally support the holding means, the bracket that can advance and retreat with respect to the work, and the first and second holding means with the respective axial directions always maintained in the same direction. Guide means for movably supporting in a direction substantially orthogonal to the axial direction of the hole portion, the guide means being elastic interposed between the first and second support plates and the bracket. A gripping device comprising: a body; and a rotating body that is rotatably provided on the bracket and that mounts the plate body in various directions in a plane substantially orthogonal to the axial direction.