JPS6234629Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a liquid supply device for liquids, particularly sealants (sealing materials), and more specifically, it is attached to the wrist, arm, etc. of a robot for sealing the body of a vehicle, etc. It concerns a liquid supply device.

Conventionally, a device is known in which a seal gun provided on the arm of a robot for sealing work and a nozzle provided at the tip of the wrist are connected by a tube made of a flexible material such as nylon.

However, with this type of device, even if the valve of the seal gun is closed to stop the pressurized supply of sealer material after each step of the prescribed sealing operation, elastic deformation of the flexible tube, etc. Therefore, the volume of the sealant supply path between the seal gun and the nozzle, in other words, the volume of the tube changes, causing the sealant to leak from the nozzle tip. In addition, even if the seal gun and nozzle are connected with a rigid pipe made of metal,
Air bubbles mixed in the sealant material kept under pressure during pressure feeding become larger when the valve is closed downstream of the valve, making it difficult to avoid leakage of sealant material from the nozzle tip when the valve is closed. . In conventional devices, this poor "cutting" makes it difficult to avoid the sealer material from adhering to areas where it should not originally be attached or from being unevenly adhered to the sealing portion.

This invention was made in view of the above points,
The object thereof is to provide a liquid supply device in which there is no risk of liquid leaking from a nozzle when the supply of liquid is stopped.

Next, a sealant supply device as a preferred example of the liquid supply device according to the present invention will be explained based on the drawings.

In the figure, 1 indicates that the sealer material delivery nozzle 2 is at the wrist portion 3.
This is the main body of a sealing robot installed in
The robot body 1 includes a base 4, a disk 5 that is rotatable in a direction A in a horizontal plane with respect to the base 4, and a column 6 that is rotatable in a direction B in a vertical plane with respect to the disk 5. A rigid arm portion 7 is rotatable in the direction C in a vertical plane with respect to the column 6, and a rigid arm portion 7 is rotatable in the direction D with respect to the arm portion 7 about an axis 7a in the extension direction of the arm portion 7. It consists of a flexible arm part 8 that can freely swing in the E direction within a plane, and a wrist part 3 provided at the tip 8a of the arm part 8. Rotation of the support column 6 relative to the support column 6 is performed by an actuator 10, rotation of the arm portion 7 relative to the support support 6 is performed by an actuator 11, and rotation of the arm portion 8 relative to the arm portion 7 and swinging of the tip 8a of the arm portion 8 are performed by actuators 12 and 13. The movable part 4 changes depending on the operation of each actuator 9 to 13.
The relative positions between 8 and 8 are determined by position detectors 14, 15,
Detected at 16, 17, and 18. When teaching is performed using this robot body 1, the nozzle 2, which is movable with respect to the tip 8a of the arm portion 8, is kept at a practically constant position with respect to the tip 8a, as described later.
Moving the nozzle 2 along with the tip 8a of the arm portion 8 along the sealing line 19 to perform a similar sealing operation,
A storage device (not shown) sequentially stores the output values of the detectors 14 to 18 at desired times during this coagulation sealing work.
Store in.

Next, when performing playback with this robot body 1, the detectors 14 to 18 at the desired time point are
actuator 9 so that the output matches the data sequentially stored in the storage device during teaching.
-13 to operate.

In the wrist portion 3 of the robot body 1, a base frame 21 of a seal portion detector 20 is fixed to the tip 8a of the arm portion 8. Reference numeral 22 denotes a movable frame connected to the base frame 21 so as to be rotatable in the direction F around an axis 23. A bevel gear 25 connected to the output shaft of 24, and this gear 25
The gear 26 is in mesh with the shaft 23 and is connected to the shaft 23. 27 is a light source configured to project a slit image onto the sealing portion Y, and 28 is a light source emitted from the light source 27 along the optical axis 29 and projecting a slit image onto the sealing portion Y.
This image detection device, such as a television camera, is configured to detect a slit image formed along an optical axis 30 that is shifted by a given angle G with respect to the optical axis 29.

The light source 27 and the image detection device 28 are each mounted on the movable frame 22.
It is fixed to , and can be rotationally displaced in the F direction with respect to the base frame 21 together with the movable frame 22 .

31 is a nozzle holder fixed to the lower part 22a of the movable frame 22, and the holder 31 supports the base 2a of the nozzle 2 via an elastic member so as to be movable in the H direction. Therefore, the nozzle 2 is movable relative to the frame 21 of the wrist 3.

This nozzle 2 includes a base 2a that is supported by a holder 31 at one end and extends substantially parallel to the optical axis 30 in the J direction, and an intermediate portion that is bent and extends laterally from the extended end of the base 2a. a shaft portion 2C bent from the extended end of the intermediate portion 2b and extending in the J direction parallel to the optical axis 30; and a tip portion 2e having an opening 2d for use. The tip 2e of the nozzle 2 is located within a plane that includes the optical axes 29 and 30, and is offset from the optical axis 30 by an amount K. Further, the tip opening 2d is located at the same distance as the intersection L of the optical axes 29 and 30 when viewed from the camera 28 in the J direction.
in front of.

In the above, the seal portion detector 20
1. Consists of a movable frame 22, a motor 24, a light source 27, and an image detection device 28. During teaching work, the movable frame 22 is placed at an initial position, for example, an optical axis 30, at a center line 30c between possible rotation limits 30a and 30b. It is set so that it is in the direction along. On the other hand, when the tip 8a of the arm 8 is set at the teaching position during playback work, whether or not the nozzle 19 is at a predetermined position (angle) with respect to the sealing part Y is determined by the light source 27 formed on the sealing part Y. It is determined whether the slit image has a given shape and position on the screen of the image detection device 28. If there is a deviation from the given shape and position, the slit image is judged by the motor 24 until the deviation disappears. The movable frame 22, the light source 27, and the image detection device 28 move in a predetermined direction from the base frame 21.
rotated against. At this time, the nozzle 2 is also rotated in the F direction with respect to the base frame 21 of the wrist 3 together with the movable frame 22. 32 is a seal gun as a valve device, and 33 is a suction device as a volume expansion device. In order to keep the moment of inertia of the wrist part 3, arms 7, 8, and column 6 that are movable around the base 4 as small as possible, and to maintain high playback accuracy and durability of the robot main body 1,
The seal gun 32 and the suction device 33 are fixed to the tip 6a of the support column 6.
A flexible tube 34 is connected to the base 2a of the nozzle 2, which is movable relative to the nozzle 2. The tube 35 connecting the seal gun 32 and the suction device 33 may be made of a flexible member or a rigid member. Incidentally, the seal gun 32 and the suction device 33 may be attached to the arm portion 7 or the disk 5.

The seal gun 32 has an inlet 37 through which sealant is introduced from a pressure source 32a serving as a hydraulic pressure source through a pipe 36, and an outlet connected to a pipe 35 to supply the sealer to a suction device 33. 38, a passage 39 that communicates the inlet 37 and the outlet 38, and a passage 39 that is provided in the passage 39 and connects the inlet 37 to the outlet 3.
a valve 42 having a valve seat 40 and a valve body 41 to allow or deny the supply of sealant to the valve body 8; a valve stem 43 extending in the M direction from the valve body 41 of the valve 42; The piston 45 is slidable in the M and N directions within the cage chamber 44, and the piston 45 is biased in the N direction via the connecting member 45a, and the valve body 41 is moved against the valve seat 40.
Compressed air is introduced into a chamber 47 defined by the spring 46 and the piston 45 to displace the piston 45 together with the valve body 41 in the M direction against the spring 46, thereby opening the passage 39. It consists of a compressed air inlet 48. In the seal gun 32, compressed air is introduced into the chamber 47 from a compressed air supply source (not shown) through the pipes 49, 50 and the inlet 48, thereby allowing the sealant material to be pumped through the outlet 38. , by opening the pipe 49 to the atmosphere (valve close signal), the valve 42 is closed and the outlet port 38 is closed.
This prevents sealant from being pumped through.

The suction device 33 has two main body forming frame members 51 and 52 screwed together. Frame member 52
includes a through hole 55 communicating with the tube 35 and the flexible tube 34 at ends 53 and 54, respectively, and an opening 56 communicating with the through hole 55 and extending laterally with respect to the hole 55. Another through hole 57 is formed. The frame member 51 has a recess 60 into which the large diameter portion 59 of the stepped piston 58 is fitted so as to be slidable in the P and Q directions, and the pipe 49 is inserted into a chamber 61 defined by the large diameter portion 59. An opening 63 to which a pipe 62 for supplying and discharging compressed air is connected, and another chamber 64
A hole 65 communicating the air with the atmosphere is provided. The small diameter portion 66 of the stepped piston 58 as a movable partition is fitted into the hole 57 so as to be slidable in the P and Q directions, and the piston 58 is biased in the Q direction by a spring 67 as a drive mechanism. has been done. 67
a is a seal ring.

In the sealant supply device 68 configured as described above, when the pipe 49 is open to the atmosphere, the valve 42 of the seal gun 32 is closed, and the suction device 33 is closed.
The piston 58 is displaced in the Q direction by a spring 67, and is connected to the hole 57 and the piston small diameter portion 66.
The volume of the variable volume space 69 formed by this is relatively large.

When supply of compressed air to the pipe 49 is started, the valve 42 of the seal gun 32 is opened, and the sealant material is supplied to the outlet 3.
8, tube 35, hole 55, tube 34 and nozzle 2
It is sent out from the tip opening 2d via the. At this time,
At the same time, compressed air is introduced into the chamber 61 through the pipe 62 and the piston 58 is moved in the P direction against the spring 67, so the volume of the space 69 becomes smaller and the expanded space 69 is filled. The sealant material that was previously used is also sent out from the tip 2d of the nozzle 2.
Therefore, compared to the case where the variable volume space 69 is not provided, delivery of the sealer material from the nozzle 2 is started promptly without any time delay, and reliable automatic control of the sealing work is possible. While the supply of compressed air to the pipe 49 continues, the piston 58 is held in the extreme position in the P direction by the compressed air in the chamber 61, so that the sealant flowing through the valve 42 flows through the nozzle 2. continues to be sent out from the tip opening 2d.

It should be noted that when the sealer material is fed out, since the sealer material is pressurized, the flexible tube 34 is slightly swollen and the tube 3 is in the state shown at 34a in FIG.
4 is deformed against its own elastic force.

On the other hand, when the supply of compressed air to the pipe 49 is stopped and the pipe 49 is opened to the atmosphere (a valve closing signal is given), the valve 42 is closed and the piston 58 of the suction device 33 is moved to the spring 67. Therefore, it is displaced in the Q direction. At this time, at the same time, the flexible tube 34 returns from the swollen state 34a to the original state 34.
b by its own elastic force, and the volume inside the flexible tube 34 decreases, but the reduced volume of sealer material is sucked into the space 69, which expands due to the movement of the piston 58 in the Q direction. Furthermore, there is no risk of the sealant material leaking from the tip opening 2d of the nozzle 2. Furthermore, even if air bubbles are mixed in the sealer material, the decrease in the sealer material storage capacity due to the expansion of the air bubbles when the valve is opened is covered by the increase in the volume of the space 69, and the sealer material is removed from the nozzle 2. There is no risk of leakage.

In the above description, a diaphragm or the like may be used instead of the piston 58 in order to form the variable volume space 69. A sealing robot 70 is formed by applying this sealer supply device 68 to the robot body 1.
Now, by fixing the sealer material supplying device 68 to the support tip 6a and attaching the nozzle 2 to the movable frame 22 which is movable with respect to the support support tip 6a and located at the tip of the wrist 3, the base 4 is fixed. Wrist part 3
Not only is the moment of inertia of the movable parts of the robot kept as small as possible, but the position of the nozzle 2 required for sealing work can be adjusted by connecting the sealer material supply device 68 and the nozzle 2 with the flexible tube 34. In addition, the variable volume space 69 prevents the sealant from leaking when the valve is closed.

In the above, a specific example in which the sealer material supply device 68 is applied to the robot body 1 has been described, but the sealer material supply device 68 is applied to the manually operated nozzle 2 through a tube such as the flexible tube 34. may also be connected.

As mentioned above, the liquid supply device of the present invention includes a pipe line that communicates with a liquid pressure source at one end and a nozzle at the other end, and a pipe line that is provided in the middle of the pipe line to disconnect communication between the nozzle and the liquid pressure source. The valve device includes a valve device, and a volume expansion device that is provided in the middle of the pipeline between the valve device and the nozzle and expands the internal volume of the pipeline, and the volume expansion device has a passage that communicates with the pipeline. a main body, a movable bulkhead provided in the passageway for expanding the internal volume of the passageway, and a movable bulkhead attached to the movable bulkhead for retracting the movable bulkhead in response to a valve closing signal of the valve device to expand the volume of the passageway. Since the nozzle includes a drive mechanism, there is no risk of liquid leaking from the nozzle tip when the liquid supply is stopped.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a sealing robot to which the liquid supply device of the present invention is applied, Fig. 2 is an explanatory diagram of the wrist tip of Fig. 1, and Fig. 3 is an explanatory cross-sectional diagram of the seal gun of Fig. 1. FIG. 4 is an explanatory cross-sectional view of the suction device of FIG. 1. 2...Nozzle, 32...Seal gun, 33...
Suction device, 34...Tube, 42...Valve, 58
...Stepped piston, 69...Volume variable space.

Claims (1)

[Scope of utility model registration request] a pipe line with one end communicating with a hydraulic pressure source and the other end serving as a nozzle; a valve device provided in the middle of the pipe line to disconnect communication between the nozzle and the liquid pressure source; and the valve device and the nozzle. and a volume expansion device installed in the middle of the pipeline to expand the internal volume of the pipeline,
The volume expansion device includes a main body having a passage communicating with the pipe, a movable partition provided in the passage to expand the internal volume of the passage, and a movable partition attached to the movable partition and linked to a valve closing signal of the valve device. and a drive mechanism for retracting the movable partition wall and expanding the volume of the passage.