JP3312257B2 - Automatic tool changer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic tool changer.

[0002]

2. Description of the Related Art An automatic tool changer has already been disclosed in Japanese Patent Application No. 5-4265. This automatic tool changer has a table D at the time of separation as shown in FIGS.
And a first unit 1 attached to the arm A of the robot, as shown in FIG. 7, and a cylinder 3 provided in the first unit 1 as shown in FIG. Release port 30 or connection port 31
(The compression spring 33 is provided in the connection port 31 of the cylinder body 35.
Supply of air to the cylinder 3
The output shaft 32 of the first unit 1 is extended or shortened, whereby the locking tool 5 is moved to connect / disconnect the second unit 2 to / from the first unit 1.

As shown in FIGS. 6 and 9, the automatic tool changer is provided with a fall-off prevention mechanism 6, which is attached to the table D side and has a disconnection port. A mechanically switching valve 9 inserted in the pneumatic circuit to 30; a second valve 2 provided on the second unit 2 side;
A dog 29 for pushing a lever 90 to open the switching valve 9 when the unit 2 is properly mounted on the mounting table D is provided.

[0004] One of the special effects of the automatic tool changer is that even if the air pressure control system malfunctions due to operator's erroneous operation or lightning or other electrical noise, the output of the robot is inadvertently output during operation. While the two units do not fall off, while the first unit 1 is separated from the second unit 2 and left for a long time, air leaks from the separation port 30 of the cylinder 3 and the locking device 5 is released. Even if the first unit and the second unit are disconnected from each other by moving to the connection position, the tool can be eliminated by supplying air to the disconnection port 30 by remote control (operation of the solenoid valve SB). And a pneumatic device for opening and closing the air circuit between the disconnection port and the air source side can be securely and with great flexibility regardless of the size of the tool mounting plate.

However, in the above automatic tool changer, when the air circuit of the fall prevention mechanism 6 is actually constituted by a tube, as shown in FIG.
The length of the tube T (from the solenoid valve SB to the tube T4 in the switching valve 9 and from the switching valve 9 to the tube T5 in the disconnecting port 30 of the cylinder 3) from the to the cylinder disconnecting port in the first unit 1 becomes longer. As a result, the pressure loss of the air flowing through the tube T increases. This causes the following problems. [When the second unit 2 is separated from the first unit 1] As described above, in this apparatus, since the pressure loss of the air flowing through the tube T is large, it is necessary to increase the pressure in the separation port 30 by a large amount. It takes time (several seconds), and a situation occurs in which the locking tool 5 does not move quickly from the connection position to the disconnection position. When such a situation occurs, the separation between the first unit 1 and the second unit 2 is incomplete, and the robot control system determines that the robot control system is abnormal and stops the robot. [When connecting the first unit 1 and the second unit 2]
In this case, the air in the disconnecting port 30 and the tube T must be discharged to the atmosphere from the solenoid valve SB at the same time as supplying the air into the connection port 31, but the pressure loss of the air flowing through the tube T is large. It takes a lot of time (several seconds or more) to discharge the air from the above-mentioned location. Therefore, even if air having a predetermined pressure is supplied into the connection port 31, the locking member 5 is quickly turned off. A situation occurs in which the user does not move from the separated position to the connection position.
When such a situation occurs, the connection between the first unit 1 and the second unit 2 is incomplete, and the robot control system determines that there is an abnormality, and the robot stops.

[0006]

Therefore, according to the present invention, even if the air pressure control system malfunctions due to an erroneous operation by an operator or lightning or other electric noise, the second output is inadvertently output from the output unit of the robot during the operation. The unit does not fall off,
Even if air leaks from the separation port of the cylinder, the disconnection state between the first unit and the second unit can be eliminated by remote control, and the separation port and the air can be removed regardless of the size of the tool or the tool mounting plate. An automatic tool changer in which a pneumatic device for opening and closing a pneumatic circuit with a source is securely and with a large degree of freedom, and a robot does not stop unintentionally during disconnection operation and connection operation of the second unit 2 with respect to the first unit 1. The task is to provide.

[0007]

According to the first aspect of the present invention, there is provided an automatic tool changing apparatus, wherein the second unit on the tool side mounted on the mounting table at the time of separation and the first unit mounted on the output section of the robot. The locking unit 5 on the first unit 1 side is moved by the supply of air to the disconnection port 30 or the connection port 31 of the cylinder 3 provided in the first unit 1 so that the first unit 1 An automatic tool changer of the type for connecting and disconnecting the second unit 2,
A pressure-sensitive actuating valve 7 inserted into an air circuit to the disconnection port 30 and attached to an output portion of the robot near the first unit 1 and opened only when air pressure acts on the pressure-sensitive portion; A valve operating air circuit 8 connecting the pressure-sensitive part of the pressure-sensitive operating valve 7 to the air source side, and a mechanical switch mounted on the table D side and inserted into the valve operating air circuit 8 A switching valve 4 which is provided on the second unit 2 side and which is provided when the second unit 2 is properly mounted on the mounting table D;
Equipped with a dog 29 for pushing the input unit to switch between
When the dog 29 is pushing the input section of the switching valve 4, air pressure acts on the pressure sensing section, and when the dog 29 is not pushing the input section, air pressure does not act on the pressure sensing section.

The automatic tool changer according to the second aspect of the present invention comprises a second unit 2 on the tool side mounted on the mounting table D at the time of separation, and a first unit 1 mounted on an output section of the robot. By supplying air to the disconnection port 30 or the connection port 31 of the cylinder 3 provided in the first unit 1, the locking unit 5 on the first unit 1 side is moved, and the second unit is moved relative to the first unit 1. An automatic tool changer of the type for connecting and disconnecting the unit 2, wherein the disconnection port 3
Pressure-sensitive actuating valve 7 which is inserted in the air circuit to the pressure sensor 0 and is attached to the output of the robot in the vicinity of the first unit 1 and opens only when air pressure is not applied to the pressure-sensitive part 7
A valve operating air circuit 8 that connects the pressure-sensitive part of the pressure-sensitive operating valve 7 to the air source side; and a mechanically mounted air valve 8 attached to the table D side and inserted into the valve operating air circuit 8. A switching valve (4) for switching, and a dog (29) provided on the second unit (2) side and for pushing an input portion to switch the switching valve (4) when the second unit (2) is properly mounted on the mounting table (D). When the input unit 29 of the switching valve 4 is pushed, air pressure does not act on the pressure sensing unit, and when the dog 29 does not push the input unit, air pressure acts on the pressure sensing unit.

[0009]

The present invention operates as follows. During the operation in which the second unit 2 is not mounted on the mounting table D, the switching valve 4 (mechanically switched) is in the closed state (the valve opening state in the second aspect of the invention). The pressure-sensitive operating valve 7 inserted into the air circuit to the port 30 is in a closed state,
As a result, even if the pneumatic control system malfunctions due to an erroneous operation by an operator or lightning or other electric noise, the second unit is not accidentally dropped from the output unit of the robot during the operation.

When the second unit 2 is separated from the first unit 1 and placed on the mounting table D, the separation port 3
Since the switching valve 4 inserted into the air circuit to the valve 0 is in an open state (closed state in the second aspect of the invention), even if air leakage from the separation port 30 of the cylinder 3 occurs. Since the moving operation of the locking member 5 is possible, the first unit and the second unit
The connection failure state with the unit can be eliminated by remote control.

In this automatic tool changer, the switching valve 4 is provided on the table D side where the piping and wiring are not arranged in a complicated manner such as around the first and second units 1 and 2. A pneumatic device for opening and closing the air circuit between the separation port 30 and the air source side can be securely and with a large degree of freedom. Further, since the switching valve 4 on the mounting table D is opened and closed by the dog 29 mounted on the second unit 2 side, a tool or a tool mounting plate mounted on the second unit 2 covers the mounting table D. Even in the case of such a size, the pressure-sensitive operation valve 7 can be reliably opened and closed via the switching valve 4 by changing the mounting position of the switching valve 4 on the mounting table D.

Further, the air circuit to the disconnection port 30 is constructed by connecting a tube directly to the first unit 1 side from the pressure-sensitive operating valve 7 attached to the output part of the robot near the first unit 1. Therefore, the length is very short (equal to the length of the air circuit to the connection port) as compared with that described in the section of the prior art, and the pressure loss of the air flowing in the air circuit is reduced. Therefore, disconnection and connection operation of the second unit 2 with respect to the first unit 1 can be performed quickly, and the robot does not stop carelessly.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. As shown in FIG. 1, the automatic tool changing device of this embodiment includes a tool-side second unit 2 mounted on a mounting table D at the time of separation, and a first unit 1 mounted on an arm A of a robot. As shown in FIG. 2, the supply of air to the disconnection port 30 or the connection port 31 of the cylinder 3 provided in the first unit 1 moves the locking tool 5 on the first unit 1 side, The second unit 2 is connected to and disconnected from the first unit 1. Further, the apparatus is provided with a falling-off prevention mechanism 6 for preventing the second unit 2 from inadvertently dropping from the first unit 1 during operation. The falling-off prevention mechanism 6 is provided as shown in FIG. A pressure-sensitive actuating valve 7 which is inserted into an air circuit to the disconnection port 30 and is attached to the arm A of the robot near the first unit 1 and opens only when air pressure acts on the pressure-sensitive portion; A valve operating air circuit 8 for connecting the pressure-sensitive part of the pressure-sensitive operating valve 7 to the air source side, and a mechanical disconnection mounted on the table D side and inserted into the valve operating air circuit 8. It has a switching valve 4 to be replaced, and a dog 29 provided on the second unit 2 side and for pushing the input portion to open the switching valve 4 when the second unit 2 is properly mounted on the mounting table D. There is a configuration.

As shown in FIG. 2, the locking member 5 is constituted by a fan-shaped cam pivotally supported by the first unit 1 and has a pair of openings 10 formed in the first unit 1. Can come and go. Cylinder 3
Has a compression spring 33 on the connection port 31 side, and a shaft 36 is provided at the rear end of the cylinder body 35, as shown in FIG. Then, the end of the output shaft 32 and the shaft 36 are attached to the locking member 5 which is a fan-shaped cam via pins, respectively. It is made to appear from.

As shown in FIG. 2, pins 20 are provided in the second unit 2 corresponding to the openings 10, respectively, and as shown by the solid line in FIG.
When it is in a state of being protruded from the second unit 2, the pin 20 is engaged with the pin 20, and the second unit 2 is held in an appropriate state with respect to the first unit 1. Thus, when the fan-shaped cam 50 is in a retracted state, the engagement with the pin 20 is released, and the second unit 2 can be separated from the first unit 1.

The pressure-sensitive actuating valve 7 is of a known structure that is switched to open when air pressure acts on the pressure-sensitive portion, and the switching valve 4 is formed of the lever 40 as described above. It has a structure that is opened and closed by switching by pushing and opening. In this embodiment, a switching operation (manual operation is also possible) in the air circuit between the air source and the cylinder 3 by an electric signal from a robot controller as shown in FIGS. The pressure-sensitive operating valve 7 is provided in a passage between the solenoid valve SB and the disconnect port 30 of the cylinder 3. In this embodiment, a well-known quick exhaust valve 99 is provided in the valve operating air circuit 8 as shown in the figure, so that the air in the separation port 30 can be quickly discharged.

The air circuit T between the disconnect port 30 of the cylinder 3 and the solenoid valve SB (the air circuit T1 connecting the pressure-sensitive operation valve 7 and the disconnect port 30 shown in FIGS. 1 and 3). The air circuit T2) connecting the solenoid valve SB and the pressure-sensitive operating valve 7, the valve operating air circuit 8, and the air circuit T 'to the connection port 31 of the cylinder 3 are all constituted by flexible tubes.

Since the automatic tool changer of this embodiment is constructed as described above, it functions as follows. (1) The second unit 2 is separated from the first unit 1
As shown in FIG. 4, when the lever 40 is pushed by the dog 29 on the second unit 2 side, the switching valve 4 is opened, and the pressure-sensitive operation valve 7 is sensed via the quick exhaust valve 99 and the like. The air pressure acts on the pressure portion, and the pressure-sensitive operation valve 7 is in an open state.

Therefore, by operating the solenoid valve SB, the cylinder 3, which is a component of the drop-out prevention mechanism 6, can be freely moved in the separating direction. As a result, air leakage from the separating port 30 of the cylinder 3 is prevented. Even if this occurs, the state in which the first unit 1 and the second unit 2 cannot be connected can be easily eliminated by operating the solenoid valve SB. (2) During operation of the robot In this case, as shown in FIG. 5, the pushing force of the dog 29 to the lever 40 is released, the switching valve 4 is closed, and the pressure-sensitive portion of the pressure-sensitive operating valve 7 No air pressure is applied, and the pressure-sensitive operating valve 7 is in a closed state.

Therefore, even if the air pressure control system malfunctions due to an erroneous operation of the operator or lightning or other electric noise and the solenoid valve SB is operated to form an air circuit, the first circuit attached to the arm A of the robot is formed. Unit 1
It does not happen that the second unit 2 is accidentally dropped from the second unit. (3) separation of the first unit 1 and the second unit 2 and
The connection operation switching valve 4 is in the same state as in the above (1), and the fall prevention mechanism 6 can be freely operated by operating the solenoid valve SB.
The output shaft of the cylinder 3, which is a component of the above, can be separated and moved in the connection direction (see FIG. 4). Therefore, disconnection and connection between the first unit 1 and the second unit 2 can be easily performed by operating the solenoid valve SB.

As described in the above (1) to (3), in the automatic tool changer of this embodiment, the second unit 2 does not drop off from the arm A of the robot during the operation.
An unconnected state between the first unit 1 and the second unit 2 can be eliminated by remote control, and a pneumatic device that opens and closes an air circuit between the separation port 30 and the air source regardless of the size of a tool or a tool mounting plate. This satisfies the condition that it can be mounted securely and with a large degree of freedom. Then, as shown in FIG. 3, an air circuit T (an air circuit T1 connecting the pressure-sensitive operation valve 7 and the separation port 30) to the separation port 30 of the cylinder 3, and an air circuit T connecting the solenoid valve SB and the pressure-sensitive operation valve 7 Circuit T
Since 2) is short, the movement of the locking member 5 at the time of the disconnection operation and the connection operation between the first unit 1 and the second unit 2 becomes agile, and the appropriate connection and disconnection operation can be performed. Therefore, the robot does not stop unexpectedly.

Although only one second unit 2 is used in the above embodiment, a plurality of second units 2 are usually used. In such a case, when the switching valves 4 are connected in series, if at least one of the second units 2 is not on the table D (that is, the second unit 2 is connected to the first unit 1 side). If so, the switching valve 4 on the mounting table D operates to close the air circuit, so that the fall prevention functions effectively.

Further, instead of the structure of the above embodiment, the pressure-sensitive operating valve 7 is closed only when air pressure acts on the pressure-sensitive part, and the second unit 2 is properly mounted on the mounting table D. The same operation and effect can be obtained by adopting a configuration including the switching valve 4 which is closed by the dog 29 when the valve 29 is closed.

[0024]

Since the present invention has the above-described configuration, it has the following effects. From the contents described in the column of action,
Even if the air pressure control system malfunctions due to an operator's erroneous operation or lightning or other electrical noise, the second unit does not accidentally fall out of the output unit of the robot during work, and air leaks from the disconnect port of the cylinder. Even if the error occurs, the connection failure between the first unit and the second unit can be eliminated by remote control, regardless of the size of the tool or the tool mounting plate.
A pneumatic device that opens and closes the air circuit between the disconnection port and the air source is securely mounted with a large degree of freedom, and the robot does not stop unexpectedly during the disconnection operation and the connection operation of the second unit 2 with respect to the first unit 1. An automatic tool changer could be provided.

[Brief description of the drawings]

FIG. 1 is a diagram showing an automatic tool changer according to an embodiment of the present invention.

FIG. 2 is a sectional view of the automatic tool changer.

FIG. 3 is an explanatory diagram in a case where a pneumatic circuit of a falling-off prevention mechanism in the automatic tool changer is constituted by a tube.

FIG. 4 is a diagram showing a state of a fall prevention mechanism of the automatic tool changer when the second unit is separated from the first unit.

FIG. 5 is a diagram showing a state of the dropout prevention mechanism during operation of the robot.

FIG. 6 shows a prior art automatic tool changer.

FIG. 7 is an explanatory view of a case in which an air circuit of a fall-off prevention mechanism in an automatic tool changer according to the prior art is configured by a tube.

FIG. 8 is a cross-sectional view of a prior art automatic tool changer.

FIG. 9 is a diagram showing a falling-off prevention mechanism of a prior art automatic tool changer.

[Explanation of symbols]

 A Arm D Mounting table 1 First unit 2 Second unit 3 Cylinder 4 Switching valve 5 Locking device 6 Drop-off prevention mechanism 7 Pressure-sensitive operating valve 8 Valve operating air circuit 30 Disconnect port 31 Connection port 40 Lever

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-117584 (JP, A) JP-A-3-117585 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B25J 15/04

Claims (2)

(57) [Claims] The first unit includes a second unit on the tool side mounted on a mounting table at the time of separation and a first unit mounted on an output unit of a robot. Disconnect port 30 or connection port 3
1. An automatic tool changer of the type in which the locking unit 5 on the first unit 1 side is moved by the supply of air to the first unit 1 to connect / disconnect the second unit 2 to / from the first unit 1. A pressure-sensitive actuating valve 7 which is inserted into an air circuit to the port 30 and is attached to an output portion of the robot near the first unit 1 and opens only when air pressure acts on the pressure-sensitive portion.
A valve operating air circuit 8 that connects the pressure-sensitive part of the pressure-sensitive operating valve 7 to the air source side; and a mechanically mounted air valve 8 attached to the table D side and inserted into the valve operating air circuit 8. A switching valve (4) for switching, and a dog (29) provided on the second unit (2) side and for pushing an input portion to switch the switching valve (4) when the second unit (2) is properly mounted on the mounting table (D). The air pressure acts on the pressure-sensitive part when 29 is pushing the input part of the switching valve 4, and the air pressure does not act on the pressure-sensitive part when the dog 29 is not pushing the input part. Automatic tool changer. 2. A cylinder 3 provided in the first unit 1 and comprising a second unit 2 on the tool side mounted on the mounting table D at the time of separation and a first unit 1 attached to an output section of the robot. Disconnect port 30 or connection port 3
1. An automatic tool changer of the type in which the locking unit 5 on the first unit 1 side is moved by the supply of air to the first unit 1 to connect / disconnect the second unit 2 to / from the first unit 1. A pressure-sensitive actuating valve 7 which is inserted into an air circuit to the port 30 and is attached to an output portion of the robot near the first unit 1 and opens only when air pressure is not applied to the pressure-sensitive portion. A valve operating air circuit 8 that connects the pressure-sensitive part of the pressure-sensitive operating valve 7 to the air source side; and a mechanically mounted air valve 8 attached to the table D side and inserted into the valve operating air circuit 8. A switching valve (4) for switching, and a dog (29) provided on the second unit (2) side and for pushing an input portion to switch the switching valve (4) when the second unit (2) is properly mounted on the mounting table (D). 29 is pressure-sensitive when pushing the input part of the switching valve 4 Automatic tool changer characterized in that the air pressure does not act, when the dog 29 is not pushed the input portion air into the pressure sensitive portion is are to be applied to.