JPS60102396A - Joint crane - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a structure in which a plurality of booms are connected to each other in series and bent by a boom cylinder at the front part of a revolving structure,
This invention relates to an articulated crane having a boom suspended by a gripping bin at its most extreme end.

An example of an articulated crane will be explained with reference to FIGS. 1 to 3, using a pipe manipulator that has already been developed by the inventors of the present invention. This pipe manipulator performs cargo handling work on pipes such as steel pipes, and has an upper rotating body 3 having a cab 5 rotatably mounted on a lower traveling body 1 via a rotating wheel 4. Boom two on the front)
A boom 6 is attached around the boom point 6a so as to be rotatable by the expansion and contraction of the boom cylinder 8, and another boom 7 is attached to the tip of the boom 6 so as to be rotatable by the boom cylinder 9 around the boom point 6b. A gripping device 10 is attached to the most distal end.

This gripping device 10 includes a frame 11 that is connected to the tip end of the boom 7 by a bin 16 and hangs down, and maintains a vertical posture regardless of the angle of the boom 7, and a swing wheel 12 that has a swing drive device 18 on the frame 11. An outer box 13 is rotatably attached via the outer box 13. The outer box 13
has a rectangular cylindrical shape, and inner boxes 14A and 14B each having a rectangular cylindrical shape are fit into the outer box 13 so as to be expandable and retractable. These boxes 13, 14A, 14B
Inside, telescopic cylinders 19A and 19B extend and contract the inch boxes 14A and 14B, respectively, and each tube is connected to the outer box 13 by a pin 19a, and each rod is connected to the inner box 14A and 1 by a pin 19b.
It is connected and attached to 4B. A pipe gripping hook 17 is attached to the tip of each of the inner boxes 14A, 14B for hanging onto the pipe 15 to be worked on. 42
is a shock absorber attached to the lower surface of the outer box 13.

Next, the function and operation of this vibe manipulator will be explained. During work, an outrigger jack 2 attached to the lower traveling body 1 is extended to stabilize it. The work is
By expanding and contracting the boom cylinders 8 and 9, the working radius from the center of the swing ring 4 to the tip of the boom 7 and the working lift height above the ground are changed to position the gripping device 10 on the vibrator 15, and the swing drive device 18, the direction of the gripping device 10 is made to match the direction of the pipe 15, and the telescopic cylinders 19A, 1
Either the gripping device 10 is stopped near the pipe 15 with 9B extended, or the cargo is placed on the pipe 15 via the buffer device 42, and the telescopic cylinders 19A and 19B are contracted to move the hook 17 onto the pipe 5. hook on both ends, actuate the boom cylinder 8.9 and pull up the gripping device 10,
The rotating body 3 is rotated to move it above the place where the pipe 15 is to be lowered, and the rotation drive device 18 is activated to adjust the direction of the pipe 15 and lower it, and the telescopic cylinder 19A is moved.

Extend 19B and remove pipe 15.

In this modern pipe manipulator, the gripping device 1
When attempting to grip the pipe 15 by using the gripping device 10, as described above, the operator
After stopping or arriving at the pipe 15, the pipe 15 is gripped.

In this gripping operation, since the boom 6.7 and the gripping device 1O are rigid bodies and are connected to each other with pins, the boom 6.7
If you press the gripping device 1O strongly against the pipe 15 by mistake, the pipe 15, the gripping device 1O, or the boom 6
．． 7 etc. may be damaged. In addition, the operator must be extremely careful to prevent damage, which not only causes fatigue for the operator but also reduces work efficiency. □In view of the above points, the present invention has a configuration that prevents damage to the gripping device, boom, or cargo handling object when the gripping device arrives at the cargo, allows work to be performed with high efficiency, and reduces operator fatigue. The purpose is to provide articulated cranes.

To achieve this object, the present invention provides an elongated hole in the frame of the gripping device that fits into the pin attached to the tip of the boom, and also has one end locked to the end of the pin. A striker whose other part is slidably held on the frame and a limit switch operated by the striker are provided, and an automatic stop means of the boom operation controller is activated by an activation signal of the limit switch when the gripping device arrives. It is characterized in that it is activated.

An embodiment of the present invention will be described below with reference to FIGS. 4 to 7, taking a pipe manipulator as an example. In FIGS. 4 and 5, 7 is a boom in the articulated crane shown in FIGS. 1 to 3, and 11 is a gripping device lO
frame, 16 is a pin for attaching the gripping device, 12 is a swing ring that rotatably supports the outer box 13, 1
8 is a swing drive device.

Therefore, in the present invention, the hole 30 of the frame 11 of the gripping device into which the pin 16 is fitted is made into an elongated hole, and
The arrival of the gripping device 10 is detected by the operation of the striker 22 and the limit switch 27. In this example,
The striker 22 has a tapered portion 22a in the middle, and the lower end of the striker 22 is connected to a lock plate attached to the end of the pin 16 by a port 21. 0
The other portion of the striker 22 is slidably held by a cylindrical portion 25a of a bracket 25 attached to the side surface of the frame 11 by bolts 26. Further, the limit switch 27 is attached to a bracket 28 which is attached to the side surface of the frame 11 with bolts 29. When the gripping device IO is supported by the boom 7, the limit switch 27 is attached to the contact roller 27a of the frame 11. is located at a narrower part r than the taper part 22a of the striker 22 and is in a non-contact state and inactive, and the gripping device io lands on the pipe 15 etc. and further lowers the boom 6 or the boom 7, When the tip of the boom 7 lowers relative to the frame 11, pin 1
6 is lowered along the elongated hole 30, the striker 22 is also pulled down, and the contact roller 27a is activated by contacting and being pushed by the thick portion of the striker 22 above the tapered portion 22a.

6 and 7 respectively show the boom cylinder 8.
9 is an operating electro-hydraulic circuit, 31° 36 is a controller for the boom cylinders 8 and 9, and 32.37 is an operating electro-hydraulic circuit.
are pipes 33° and 34' to boom cylinder 8.9, respectively.
and conduit 38゛.

These switching valves 32, 37 are connected to each controller 31, 36 by signal paths 33, 34 and 38, 39, respectively.

When the controller 31 (36) is operated in the A direction (C direction), the switching valve 32 (
An extension command signal is applied to the boom cylinder 8 (9), and by switching these valves, a pressure of 7 m is supplied to the boom cylinder 8 (9) via the pipe 33'(3B').
) expands, and when the controller 31 (36) is operated in the B direction (D direction), a contraction command signal is applied to the switching valve 32 (37) via the signal path 34 (39), which is the opposite of the above. By switching the valve, pressurized oil is supplied to the boom cylinder 8 (9) through the pipe 34'(39''), and the boom cylinder 8 (9) is extended.

In this embodiment, the limit switch 27 is connected to the signal path 34 for the contraction command signal of the boom cylinder 8, the signal path 38 for the extension command signal and the signal path 39 for the contraction command signal of the boom cylinder 9, respectively. An automatic stop means 35, 40, 41, such as a relay or the like, is provided which applies a force to the corresponding signal path when activated, and when the gripping device io arrives at the pipe 15 and the limit switch 27 is activated,
Boom cylinder 8 contraction command signal and boom cylinder 9
The extension command signal and the contraction command signal are sent to the controller 31.
．． Regardless of whether 38 is operated or not, the signal is not transmitted to switching valves 32 and 37.

Therefore, due to the arrival of the 5 gripping device 10, the boom cylinder 8
The contraction operation of the boom cylinder 9 and the expansion and contraction operation of the boom cylinder 9 are automatically stopped.

In this way, even if the operator moves the boom 6.7 downward after the gripping device 10 has landed on the pipe 15, the pin 16 will not press against the gripping device 10 or the pipe 15 due to the play in the elongated hole 30, and these Damage is prevented, and the striker 22 operates the limit switch 27 in conjunction with the pin 16, and this activation signal causes the automatic stop means 3 to operate.
5, 40.41, the lowering direction of boom 6, boom 7
Since the movement in both directions of raising and lowering is automatically stopped, the safety of pipe gripping work is ensured.

After the cargo arrives and automatically stops, if the telescopic cylinder 19 shown in FIG. 3 is retracted to reduce the distance between the hooks 17, the pipe 1
5 is held by a hook 17. then controller 3
1 in the A direction, the signal causes pressure oil to flow into the pipe 33' via the switching valve 32, and the boom cylinder 8 moves again in the extension direction, causing the boom 6 to rotate upward around the boom foot 6a. . When the pin 16 hits the upper end of the long hole 30 of the frame 11, the taper portion 22a of the striker 22 separates from the contact roller 27a of the limit switch 27, and the automatic stop described above is canceled.

Here, the reason why the automatic stop is performed only in the contraction direction for the boom cylinder 8 and in both the expansion and contraction directions for the boom cylinder 9 is as follows.

When the boom cylinder 8 is retracted, the boom 6 always rotates downward around the boom 2) 6a, but the boom 7 rotates downward around the boom 6a.
Since the boom 6 rotates around the boom point 6b at the tip of the boom 7, when the boom 6 is lowered from the state shown in FIG.
The tip of will now descend instead of ascending. For this reason, for safety reasons, the boom cylinder 9 of the boom 7 is automatically stopped in both directions of expansion and contraction upon arrival of the cargo.

Although the above explanation has been made regarding a pipe manipulator, the present invention is an articulated crane in which a plurality of booms are connected in series and bent by a boom cylinder. This applies to everything that is provided.

As described above, according to the present invention, in an articulated crane having a gripping device at the tip of the boom, damage to the load, the gripping device, the boom, etc. when the gripping device lands is prevented. In addition, since the boom can be operated quickly until the cargo arrives, work can be done with high efficiency, and the operator can work with peace of mind, reducing the operator's workload and fatigue. I can do it.

[Brief explanation of the drawing]

Fig. 1 is a side view showing a pipe manipulator already developed by the present inventors in a working posture, Fig. 2 is a plan view thereof, Fig. 3 is a view taken along arrow A-A in Fig. 1, and Fig. 4 The figure is a front view of a gripping device showing an embodiment of the present invention, FIG. 5 is a view taken along the line B-B in FIG. 4, and FIGS. 6 and 7 are examples of an electro-hydraulic circuit for boom operation according to the present invention. It is a diagram. 6.7...Boom, 8,9...Boom cylinder, 1
0... Gripping device, 11... Frame, 16... Pin, 22... Striker, 27... Limit switch, 30... Elongated hole, 31.36... Controller,
32, 37...Switching valve, 35,40.41...Automatic stop means patent applicant Hitachi Construction Machinery Co., Ltd. Agent Patent attorney Masami Akiki Agent Patent attorney Masaru Wakata

Claims (1)

[Claims] An articulated crane in which a plurality of booms connected in series and bent by a boom cylinder are attached to the front part of a revolving body, and a gripping device is suspended from a bin at the tip of the boom, and the gripping device is fitted into the bin. A striker having an elongated hole in a frame of a gripping device, one end of which is locked to the end of the bottle, and the other part slidably held by the frame, and a limit operated by the striker. An articulated crane comprising: a switch, and an automatic stop means of a boom operation controller is activated by an activation signal of the limit switch when the gripping device arrives.