JPH0546872Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention can be used, for example, in automatic assembly equipment.
A centering device that can automatically perform centering with respect to a fitting hole when fitting a member into a fitting hole, especially a centering device that is inserted between a machine body such as a robot and a terminal device such as a hand. This invention relates to a centering device.

[Prior Art] Generally, in an automatic assembly device, in order to insert a member into a predetermined fitting hole, the member and the fitting hole must be aligned with each other, in other words,
It is necessary to perform alignment so that the central axes are located on the same straight line.

Therefore, for example, JP-A-61-216399, JP-A-Sho.
No. 59-88284 has proposed a device that is attached to a robot hand and aligns parts.

In order to align the members and the fitting holes with each other in this manner, conventionally, an alignment device inserted between the assembly robot and the robot hand has been employed. This centering device allows a member to be reliably fitted into a fitting hole formed in a member to be attached, even if the center axes of the members are slightly deviated from each other.

Here, in the conventional alignment device, when the robot hand suddenly moves in a horizontal plane while the alignment is being performed, due to the softness of the compliance device itself and the inertia of the robot hand,
The robot hand will be deflected in the lateral direction, and in the worst case, the robot hand will come off the robot arm.

[Problem to be solved by the invention] For this reason, when the robot arm is driven, that is, when the robot hand is moved, a locking mechanism is adopted to eliminate the softness of the centering device and integrate it. There is.

However, in the conventional lock mechanism,
There was no way to efficiently execute the lock operation, and improvements were desired.

This invention was made in view of the above-mentioned circumstances, and the purpose of this invention is to create a space between the mounting body of the machine body and the terminal device mounting body to which the terminal device is attached, which is held movably relative to this mounting body. It is an object of the present invention to provide an alignment device that can ensure sufficient compliance in the process and can sufficiently follow even when the main body of a machine such as a robot is moved at high speed.

[Means for solving the problem] In order to solve the above-mentioned problem and achieve the purpose,
The alignment device according to this invention is an alignment device that is inserted between a machine body such as a robot and a terminal device such as a hand, and restores mutual positional deviation between the machine body and the terminal device. , a mounting body of the machine body, and a first body extending from the mounting body.
a shaft member, a terminal device mounting body to which the terminal device is attached and held movably relative to the mounting body;
A second shaft member extends toward the shaft member, and surrounds the first shaft member and the second shaft member around mutually opposing end surfaces of the first shaft member and the second shaft member. Compliance is obtained from a plurality of support members disposed in A locking means that constitutes a unit and restricts the relative movement between the mounting body and the terminal device mounting body is disposed on a concentric circle in which the compliance unit is disposed.

[Operation] In the alignment device configured as described above, the locking means is positioned on a circle substantially concentric with the concentric circle in which the compliance unit is disposed. As a result, locking operations can be performed efficiently.

[Embodiment] Below, the configuration of an embodiment of the centering device according to the present invention will be described in detail with reference to FIGS. 1 to 6B of the accompanying drawings.

FIG. 1 shows a state in which a hand portion 14 is attached to the tip of a robot arm 10, which constitutes a part of an assembly robot as an automatic assembly device, via a centering device 12 of this embodiment. ing. The robot arm 10 is driven to move freely in the left-right direction (x-axis direction), the direction perpendicular to the page (y-axis direction), and the vertical direction (z-axis direction) in the figure by a drive mechanism (not shown). It is something that

On the other hand, the hand part 14 has an upper surface opened by a circular opening having a first diameter, and a cylindrical hollow part having a second diameter set larger than the first diameter. It includes a main body 16 and a holder 20 fixed to the lower surface of the hand main body 16 via a bolt 18. This holder 2
0, there is a round bar-shaped pin 2 extending along the vertical direction, opening at the lower surface, and serving as a fitting member.
An insertion hole 24 into which 2 is inserted is formed.

Here, a suction pipe 26 connected to a suction pump (not shown) is connected to the upper part of this insertion hole 24 so as to communicate therewith. By driving this suction pump, the inside of the insertion hole 24 is maintained in a negative pressure state, and the pin 22 is suctioned and held within the insertion hole 24 by this negative pressure.

Also, a fitting hole 28 into which this pin 22 is fitted
is formed on the substrate 30 as a member to be fitted. This substrate 30 is mounted horizontally on a base (not shown), and in this state, the fitting hole 28 is set to extend in the vertical direction. Note that a pin 22 is provided on the upper edge of this fitting hole 28.
In order to facilitate fitting, a tapered surface 32 is formed with a predetermined inclination with respect to the horizontal surface.

Here, the centering device 12 of the above-mentioned embodiment
The robot arm 10 includes a pair of compliance mechanisms 34 and 36 arranged at symmetrical positions with respect to the central axis of the robot arm 10. The compliance device 12 also includes a disk-shaped mounting body 40 fixed to the lower end of the robot arm 10 via a bolt 38, and a support body 44 fixed to the lower surface of the mounting body 40 via a bolt 42. It is equipped with

This support body 44 has the above-mentioned first
A cylindrical portion 44 having a third diameter smaller than the diameter of
a, and a second diameter which is integrally formed at the lower end of the columnar part 44a, and which is larger than the first diameter described above.
The flange portion 44b has a fourth diameter smaller than the diameter of the flange portion 44b. With this configuration, the hand main body 16 to which the holder 20 is fixed is suspended from the support main body 44 fixed to the lower end of the robot arm 10.

Here, the upper surface of this flange portion 44b is
through the ball bearing 46 of the hand body 1.
The lower surface of the flange portion 44b contacts the upper surface of the hollow portion of the hand body 16 so as to be rotatable and movable within the horizontal plane, and the lower surface of the flange portion 44b contacts the lower surface of the hollow portion of the hand body 16 via the second ball bearing 48. It contacts freely rotatably and movably within a horizontal plane. In this way, the holder 20 is held in a state where it can freely move and rotate in the horizontal plane with respect to the robot arm 10.

Here, in the pair of compliance mechanisms 34 and 36 described above, in a normal state, when no external force is acting on the holder 20, the central axis of the robot arm 10 and the central axis of the holder 20 are mutually aligned. , while elastically maintaining the aligned state along the vertical direction, and allowing the retainer 20 to be softly deflected within a predetermined range in response to an external force in the horizontal plane when this external force is applied to the holder 20. It is set up so that it can be done.

In addition, below, the compliance mechanisms 34, 36
As shown in FIG. 2, both compliance mechanisms 34 and 36 are located at opposing positions on the same circumference centered on the central axis of the robot arm 10, in other words. ,
They are located on the same diameter and have the same configuration. Therefore, only the configuration of the compliance mechanism 34 on the left side of the figure will be described in detail, and the description of the configuration of the compliance mechanism 36 on the right side of the figure will be omitted by adding the same alphabetical subscripts.

That is, the compliance mechanism 34 includes a first shaft member 34a attached to the lower surface of the attachment body 40 so as to protrude downward, and a holder 20.
A second shaft member 34b is attached to protrude toward the upper surface of the hand body 16 in alignment with the first shaft member 34a in the vertical direction when no external force is applied to the second shaft member 34b. It is equipped with

These first and second shaft members 34a, 34b
are formed to have outer circumferential surfaces having the same radius, and the lower end of the first shaft member 34a is
The second shaft member 34b is set to face and be slightly spaced apart from the upper end of the second shaft member 34b.

Further, this compliance mechanism 34
A plurality of support pins 34c are provided as support members disposed so as to simultaneously surround the opposing ends of the second shaft members 34a and 34b. Specifically, in this embodiment, these support pins 34c are formed from a cylindrical body having the same radius as the first and second shaft members 34a and 34b, and the number of support pins 34c is six. is set to . These six support pins 34c are arranged so as to simultaneously surround the opposing ends of the first and second shaft members 34a and 34b without any gaps.

Here, each support pin 34c has an annular cut groove 34d formed at its upper end and lower end, respectively. These support pins 34c are connected to both shaft members 3
4a, 34b, and surround these support pins 34c all at once,
Each cut groove 34d has a ring-shaped biasing member 34e that biases the support pins so as to elastically press against the circumferential surfaces of the opposing ends of the first and second shaft members 34a and 34b. are stored respectively.

Note that in this embodiment, this biasing member 3
4e is formed from a finely wound ring-shaped coil spring.

Moreover, as shown in FIG. 3, this alignment device 1
2 includes a pair of locking mechanisms 50 and 52 to prevent the hand body 16 from shifting laterally with respect to the mounting body 40 due to inertia when the robot arm 10 moves laterally at high speed. It is provided.

The structure of the lock mechanisms 50 and 52, which characterizes this invention, will be explained below. Here, as shown in FIG. 2, both the lock mechanisms 50 and 52 are located on the same circumference around the central axis of the robot arm 10 as the pair of compliance mechanisms 34 and 36. , are located opposite to each other on a diameter perpendicular to the predetermined diameter on which both compliance mechanisms 34 and 36 are located, and both have the same configuration. For this reason, only the configuration of the lock mechanism 50 in the upper part of the figure will be explained in detail, and the structure of the lock mechanism 52 in the lower part of the figure will be explained in detail.
The explanation of the structure of is omitted by adding the same alphabetical subscript.

This lock mechanism 50 includes a cylinder 50a built into the mounting body 40. A piston member 50b is housed in the cylinder chamber 50a so as to be able to protrude downward. Here, the piston member 50b is urged upward by a coil spring 50c, and a stopper member 50d integrally formed with the upper end of the piston member 50b is projected upward by the urging force of the coil spring 50c. At the position where the piston member 5 comes into contact with the upper surface of the cylinder chamber 50a and stops, the piston member 5
The retraction position of 0b is defined.

Further, on the upper surface of the hand body 16, a lock hole 5 is provided at a position opposite to the tip of each piston member 50b, into which the tip of the corresponding piston member 50b is fitted.
0e is formed. Here, a connecting pipe 50f connected to a pressurizing pump mechanism 56 via a solenoid valve 54 is connected to a portion of each cylinder chamber 50a described above above the upper end of the piston member 50b.

When the electromagnetic valve 54 opens, compressed air (pressurized air) is introduced into the cylinder chamber 50a from the pressurizing pump mechanism 56 via the connecting pipe 50f, so that each piston member 50b is moved into the corresponding piston member 50b. Against the biasing force of the coil spring 50c,
It is pushed downward from the retracted position and biased to the locked position. In this lock position, the lower end of each piston member 50b fits into the corresponding lock hole 50e. In this way, when the locking mechanism 50 is activated, the hand main body 16 and the mounting main body 40 are locked to each other in the lateral direction, and are moved laterally as a unit.

The alignment operation in the compliance device 12 configured as described above will be described below.

With the pin 22 suctioned and held in the holder 20,
The robot arm 10 connects this pin 22 to the substrate 30.
Its movement is controlled by a control mechanism (not shown) so that it fits into the fitting hole 28 formed in the . That is, in this control mechanism, the x-
Position information on the y-plane and robot arm 1
0 three-dimensional position, that is, the pin 22 to be inserted
The positional information of the robot arm 10 is inputted, and the movement of the robot arm 10 is controlled by the control operation of the control mechanism based on this positional information.

Here, by controlling the movement of the robot arm 10, when the robot arm 10 is moving along the horizontal direction, that is, within the x-y plane, the solenoid valve 54 is opened.
From the pressurizing pump mechanism 56, both locking mechanisms 50, 5
Compressed air will be supplied to 2. In this manner, each piston member 50b, 52b is pushed downward from the retracted position against the biasing force of the corresponding coil spring 50e, 52e, and biased to the locked position as shown in FIG.

In this way, both the lock mechanisms 50, 52 are activated and are in the operating state, and each piston member 50b, 52 is activated.
2b is brought to the lock position and fitted into the corresponding lock holes 50e, 52e, the hand main body 16 and the mounting main body 40 are locked to each other in the lateral direction, and cannot be moved laterally as a unit. Become.

On the other hand, by controlling the movement of the robot arm 10, it can move along the vertical direction, i.e., x-z or y-
In the state of movement within the z plane, the solenoid valve 54
is closed, and compressed air is no longer supplied from the pressurizing pump mechanism 56 to both locking mechanisms 50 and 52. In this way, each piston member 50b, 5
2b is the corresponding coil spring 50e, 52
It is pushed upward from the lock position to the retracted position by the biasing force e, and is biased to the retracted position as shown in FIG.

Both locking mechanisms 50, 52 are thus inactivated, each piston member 50b, 52b is brought to the retracted position, and the corresponding locking hole 50 is brought into the retracted position.
e, 52e are pulled out, the hand main body 16 and the attachment main body 40 are brought into a state in which they can move freely relative to each other in the lateral direction.

Also, here we confirm that these location information are accurate and
When the robot arm 10 is moved and driven according to the control contents of the control mechanism, and when the fitting hole 28 is positioned according to the set value, a hole is placed directly above the fitting hole 28 according to the movement control operation described above. Based on this, the pin 22 is moved and then lowered in the vertical direction, so that the pin 22 fits well into the fitting hole 28.

However, the positioning of the fitting hole 28 may not be accurate, and may deviate slightly from the set value in the There may be cases where the position is slightly deviated from the specified position.

If such a shift occurs, the pin 22, which has been vertically lowered due to the lowering of the robot arm 10, will move as shown in FIGS. 1 and 5.
The lower edge thereof comes into contact with the tapered surface 32 of the fitting hole 28. Then, as the robot arm 10 further descends, the lower end edge of the pin 22 receives a component force F directed in the horizontal direction along the tapered surface 32.

Here, as described above, the robot arm 10
When the lock mechanism moves in the vertical direction, both lock mechanisms 50 and 52 are in a non-operating state. Therefore, the hand main body 16 and the attachment main body 40 can be laterally displaced relative to each other. As a result, the pin 22 receives the above-mentioned horizontal component force F, and this component force F is applied to the hand bodies 16 and 3 of the compliance mechanisms 34 and 36 via the holder 20 and the hand body 16.
6b.

Therefore, when this component force F is not acting, as shown in FIG. 6A, the pair of upper and lower biasing members 34e and 36e elastically move the first and second shaft members 34a, 34b, From the state in which the biasing members 36a and 36b are vertically aligned with each other, as shown in FIG. 6B, the biasing members 34e and 3
Support pins 34c and 36c resist the urging force of 6e.
By tilting diagonally, the second members 34b, 3
6b will move so as to be shifted in the horizontal direction.

In addition, when moving in the horizontal direction, as shown in FIG. 6B, the hand main body 16 to which the hand main body 16 is attached does not tilt its posture, but allows the pin 22 to extend vertically. It will be moved with support. Therefore, the subsequent insertion operation can be performed very easily.

In this way, the misalignment between the pin 22 and the fitting hole 28 can be avoided in the first and second shaft members 34a, 34b, 36 in each compliance mechanism 34, 36.
The deviation of the pins 22 and 36b is elastically absorbed, and the pin 22 and the fitting hole 28 are brought into alignment with each other along the vertical direction, and the robot arm 10
As the pin 22 is lowered, the pin 22 is properly fitted into the fitting hole 28.

After the operation of fitting the pin 22 into the fitting hole 28 is completed, the drive of the suction pump (not shown) is stopped and the robot arm 10 is driven upward.
The holding state of the pin 22 in the holder 20 is released, and the hand portion 14 lifts up independently with the pin 22 released. Then, when the pin 22 is completely separated from the holder 20, the above-mentioned component force F no longer acts on the holder 20. As a result, in both the compliance mechanisms 34 and 36, the second shaft member 3
4b, 36b is eliminated, and the hand main bodies 16, 36b are moved to the sixth position by the urging force of the pair of upper and lower urging members 34e, 36e.
The biased state shown in Figure B is successfully returned to the aligned state shown in Figure 6A.

In this way, this compliance device 1
In other words, the elastic biasing/returning operation in the compliance mechanisms 34 and 36 ends.

As described in detail above, in this embodiment, the pair of locking mechanisms 50 and 52 are arranged so as to face each other on a diameter perpendicular to the predetermined diameter at which the compliances 34 and 36 are provided,
Further, the compliance mechanisms 34 and 36 are arranged so as to be located on a substantially concentric circle with the concentric circle in which the compliance mechanisms 34 and 36 are provided. In this way, in this embodiment, the locking operation is performed efficiently and reliably.

It goes without saying that this invention is not limited to the configuration of the one embodiment described above, and various modifications are possible without departing from the gist of this invention.

For example, in one embodiment described above, pin 2
2 has been described as being held in a vacuum-suctioned state in the insertion hole 24 formed in the holder 22, but
The mechanism is not limited to this, and may be a magnetic attraction using a magnet or a mechanical locking mechanism using a mechanical finger.

Furthermore, in the embodiment described above, the hand portion 1
Although it has been described that the hand body 16 of No. 4 and the support body 44 of the robot arm 10 are rotatably supported by the first and second ball bearings 46, 48, the present invention is not limited to such a configuration. Alternatively, the structure may be such that it is supported by an air bearing.

Further, in the above-described embodiment, a pair of locking mechanisms 50 and 52 are provided as the locking means, but the present invention is not limited to such a configuration, and the locking means may be provided with a single locking mechanism. It may be configured to include only a lock mechanism. In this case, it is preferable that the lock hole and the piston member inserted into the lock hole are complementary to each other and have rectangular shapes.

[Effects of the invention] As detailed above, according to the invention, there is sufficient distance between the mounting body of the machine body and the terminal device mounting body to which the terminal device is attached, which is held movably relative to the mounting body. It is possible to provide an alignment device that can ensure compliance and can sufficiently follow even when a machine body such as a robot is moved at high speed.

[Brief explanation of the drawing]

Fig. 1 is a front view, partially cut away, showing the configuration of an embodiment of the centering device according to this invention;
The figure is a plan cross-sectional view taken along the - line in Fig. 1, and Fig. 3 shows the centering device taken along the - line in Fig. 2.
FIG. 4 is a longitudinal sectional view showing the locking mechanism in a non-operating state, FIG. 4 is a longitudinal sectional view showing the centering device shown in FIG. FIG. 6A is a front view partially showing a state in which the first and second shaft members are aligned with each other, and FIG. 6B is a plan view showing a state in which the first and second shaft members are aligned with each other. It is a front view partially showing a state in which the first and second shaft members are shifted from each other. In the figure, 10... Robot arm, 12... Center alignment device, 14... Hand section, 16... Hand body, 18... Bolt, 20... Holder, 22...
Pin, 24...Insertion hole, 26...Suction tube, 28...
...Fitting hole, 30... Board, 32... Tapered surface, 3
4, 36... Compliance mechanism, 34a, 3
6a...first shaft member, 34b, 36b...second
shaft member, 34c, 36c... support pin, 34
d, 36d...cut groove, 34e, 36e...biasing member, 38...bolt, 40...mounting body, 42
... Bolt, 44 ... Support body, 44a ... Cylindrical part, 44b ... Flange part, 46 ... First ball bearing, 48 ... Second ball bearing, 50, 52 ... Lock mechanism, 50a, 50a
...Cylinder chamber, 50b, 52b...Viston member, 50c, 52c...Coil spring, 50
d, 52d... Stopper member, 50e, 52e...
...Lock hole, 50f, 52f...Connecting pipe, 54...
... Solenoid valve, 56 ... Pressure pump mechanism.

Claims (1)

[Claims for Utility Model Registration] An alignment device that is inserted between a machine body such as a robot and a terminal device such as a hand to restore mutual positional deviation between the machine body and the terminal device, a mounting body of the machine body; a first shaft member extending from the mounting body; a terminal device mounting body to which the terminal device is attached and held movably relative to the mounting body; and the terminal device. a second shaft member extending from the main body toward the first shaft member; and a second shaft member extending between the first shaft member and the second shaft member around mutually opposing end surfaces of the first shaft member and the second shaft member. a plurality of support members arranged to surround the member; and a biasing member that elastically surrounds the support members and biases the first shaft member and the second shaft member so that their axes coincide with each other. A core is characterized in that a compliance unit is constituted by a biasing member, and a locking means for regulating the relative movement between the mounting body and the terminal device mounting body is disposed on a concentric circle on which the compliance unit is disposed. Aligning device.