JPH0581178U - Grab bucket - Google Patents

Abstract

(57) [Abstract] [Purpose] A bucket that opens and closes the shell by attaching and detaching the movable sheave block and the lower frame of the grabbucket for cargo handling, and also opens and closes the solenoid valve to attach and detach the movable sheave block and the lower frame. In addition to the hydraulic cylinder device, it is not necessary to install the detachable locking parts for the movable sheave block and the lower frame, the guide shaft of the movable sheave block, and the consumable parts such as the hydraulic shock absorber in the type type, and the structure is greatly improved. The purpose of the present invention is to simplify and provide at low cost, and to smoothly lower the piston of the hydraulic cylinder device. [Structure] A hydraulic cylinder 12 is fixed to a lower frame 3, a piston rod 13 is fixed to a movable sheave block 2, and a check valve 19 is formed on a piston 16. The cylinder head side chamber 17 and the oil tank 22 are connected. A solenoid valve 29 is provided in the middle of a conduit connecting the piston rod side chamber 18 and the cylinder head side chamber 17.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a grab bucket which is suspended by a crane or the like and is used for loading and unloading loose items.

[0002]

[Prior Art]

 The inventor of the present application once devised the single glove bucket described in Utility Model No. 61-1180. In this conventional example, a movable sheave block, which is separate from the lower frame, is connected to a lower frame connected to a shell and raised to close the shell, and the lower frame is detached from the movable sheave block and lowered. A grab bucket that opens the shell by making the pair of left and right pawls pivotally attached to the lower frame, and the pair of left and right pawl locking pieces pivotally attached to the movable sheave block. The hydraulic cylinder device is connected to the claw of the claw, and the claw and claw locking piece are attached and detached by expansion and contraction of the hydraulic cylinder device, whereby the movable sheave block and the lower frame are attached and detached to open and close the shell. In addition, a solenoid valve is inserted in the middle of the hydraulic circuit of the hydraulic cylinder device, and the solenoid valve is expanded and contracted by opening and closing the solenoid valve. It is obtained by allowing the remote operation by by Ri radio signal to be used the valve.

[0003]

[Problems to be solved by the device]

 In the case of the conventional example, firstly, the pawl and the pawl locking piece are required, and the structure is complicated. Even if the pawl and the pawl locking piece are frictionally slid while the full load is applied when the pawl is opened. However, since it disengages, the claw locking part is easily worn and cannot be used for many years. Second, in order to move the movable sheave block up and down accurately, a pair of guide shafts are required to pass through the movable sheave block in the front-rear direction or the left-right direction. Third, a hydraulic shock absorber is required to connect the shell and the upper frame with the sheave in order to gently open the shell. As described above, the conventional example has a large number of parts, has a complicated structure, and is difficult to provide at low cost. In addition, maintenance costs are high due to wear of parts.

[0004]

[Means for Solving the Problems]

 This invention solves the above-mentioned inconvenience, that is, the lower frame connected to the shell is integrated with a movable sheave block separate from the lower frame to raise the movable sheave block, thereby closing the shell and closing the lower frame. In the grab bucket that opens the shell by detaching from the movable sheave block and lowering it, fix the hydraulic cylinder to the lower frame, fix the piston rod to the movable sheave block, and attach the check valve to the piston. A cylinder head side chamber and an oil tank are connected through a first conduit, a solenoid valve and a piston rod side chamber are connected through a second conduit, and the solenoid valve and the cylinder head are connected through a third conduit. It is characterized in that it is connected to a side chamber and that the oil tank and the solenoid valve are attached to the lower frame. That.

[0005]

【Example】

 The embodiment is a single rope grab bucket. As shown in FIGS. 1 to 4, the upper frame 1, the movable sheave block 2 and the lower frame 3 are separately formed, and the shells 4 and 4 are axially attached to the lower frame 3. And then line up. As shown in the above figures and FIGS. 5 and 7, the sheaves 5 and 6 are attached to the upper frame 1, and the sheaves 7 and 8 are attached to the movable sheave block 2, and one end of the rope 9 is attached to the movable sheave block as is apparent from FIG. The rope 9 is fixed to 2, and the rope 9 is hung around the support hanger 10 via the sheaves 5 and 7, and the other end of the rope 9 is fixed to the movable sheave block 2 via the sheaves 8 and 6.

As shown in FIGS. 1 to 4, the upper ends of the rods 11 and 11 are axially attached to the upper frame 1, and the lower ends of the rods 11 and 11 are axially attached to the left and right of the shells 4 and 4, respectively. Due to the weight of 4 and 4, the shells 4 and 4 are formed so as to be opened as shown in FIGS.

As shown in FIGS. 3 to 5, the hydraulic cylinder 12 is fixed to the lower frame 3, and the upper end of the piston rod 13 is fixed to the top of the chevron portion 14 of the movable sheave block 2. When the movable sheave block 2 is raised, the chevron portion 14 enters into the upper frame 1 as shown by the broken line in FIG. 4, and reference numeral 15 in FIG. 5 is a storage boss integrated with the hydraulic cylinder 12. A packing 40 and a bush 41 for preventing oil leakage are attached to the storage boss 15. As shown in FIGS. 5 and 6, the piston 16 is provided with a check valve 19 through which oil passes only from the cylinder head side chamber 17 to the piston rod side chamber 18.

As shown in FIGS. 1 to 5, an oil tank 22 is attached to the left side plate 20 of the lower frame 3 and an equipment box 23 is attached to the right side plate 21. As shown in FIG. 5, one end of each of the first conduit 25 and the third conduit 26 is connected to the cylinder head side chamber 17 via the common oil passage 24, and the other end of the first conduit 25 is connected to the oil tank 22.

One end of the second conduit 27 is connected to the piston rod side chamber 18, and a flow control valve such as a throttle valve is interposed in the middle of the second conduit 27 as a valve 38 for adjusting the opening speed of the shells 4, 4. , The other end of the second conduit 27 is connected to a solenoid valve 29 that is opened and closed by the wireless signal receiver 28, and the other end of the third conduit 26 is connected to the solenoid valve 29. The electromagnetic valve 29 is opened via the wireless signal receiver 28 when the opening switch 33 of the wireless signal transmitter 32 is turned on, and is opened via the wireless signal receiver 28 when the closing switch 34 is turned on. Once closed, once the wireless signal receiver 28 receives the open or close signal, the solenoid valve 29 continues to open or close even if the open or close signal is cut off thereafter. Then, the valve 38, the solenoid valve 29, the radio signal receiver 28 and the battery 30 thereof are incorporated into the equipment box 23. In the figure, reference numeral 31 is an antenna of the radio signal receiver 28, and in this embodiment, a switch 35 is pressed at the same time when the movable sheave block 2 comes into contact with the lower frame 3 to close the solenoid valve 29. Install on 23.

Next, the operation of the embodiment will be described. First, the valve 38 is throttled and adjusted so that the shells 4 and 4 have a desired opening speed. Now, as shown in FIGS. 1 and 2, when the shells 4 and 4 are closed and the entire grab bucket is suspended in the air by the hook 37 of a crane or the like, the switch 33 for opening the wireless signal transmitter 32 is opened. When the button is pressed, an open signal is transmitted, received by the wireless signal receiver 28, and controlled to open the solenoid valve 29. Here, once the solenoid valve 29 of this embodiment receives the open signal by the wireless signal receiver 28, the solenoid valve 29 continues to open even if the open signal is cut off thereafter. After pressing the button 33 to open the solenoid valve 29, the button of the opening switch 33 is immediately released to cut off the opening signal.

When the solenoid valve 29 is opened, the oil in the hydraulic circuit is in a state where it can circulate, and the shells 4 and 4 open due to their own weights as shown in FIG. 3 around the shaft attachment position of the lower ends of the rods 11 and 11. Along with this, the lower frame 3 and the hydraulic cylinder 12 connected to the shells 4 and 4 also descend. At this time, as the hydraulic cylinder 12 descends, the oil in the piston rod side chamber 18 of FIG. 5 is pushed by the piston 16 and flows to the valve 38 and the solenoid valve 29 via the second conduit 27, and further from the third conduit 26 to the common oil passage. The oil that has entered the cylinder head side chamber 17 via 24 and is also sucked into the hydraulic cylinder 12 through the first conduit 25 and the common oil passage 24 up to the broken line position in the oil tank 22 in FIG. Reduced to. The amount of oil reduced in the oil tank 22 is the volume of the piston rod 13 that has come out of the hydraulic cylinder 12.

After opening the shells 4 and 4 in the air in this way, the crane is lowered to land on the object with the shells 4 and 4 open. After the landing, when the rope 9 is lowered together with the support hanger 10, the upper frame 1 is in a stationary state via the shells 4 and 4 and the rods 11 and 11 that have landed, so that as shown by the chain line in FIG. The movable sheave block 2 moves down apart from the upper frame 1 and eventually comes into contact with the lower frame 3. When the movable sheave block 2 is lowered, the piston rod 13 and the piston 16 are also lowered. Explaining this with reference to FIG. 5, the piston 16 at the chain line position descends to the solid line position. At this time, however, since the check valve 19 is formed in the piston 16, the piston 16 at the chain line position is closer to the piston 16. The oil in the hydraulic cylinder 12 located below passes through the check valve 19 and becomes the upper side of the piston 16, and when the piston 16 is in the position shown by the solid line, the piston rod 13 is equivalent to the volume inserted in the hydraulic cylinder 12. Oil flows into the oil tank 22 via the first conduit 25, and the oil in the oil tank 22 increases from the chain line position to the broken line position. Since the oil passes through the check valve 19 as described above, the piston 16 descends smoothly.

When the movable sheave block 2 descends and contacts the lower frame 3 in this way, the button 36 of the switch 35 projecting to the position shown by the chain line in FIG. 5 is pressed to close the solenoid valve 29. Here, by closing the solenoid valve 29 and the check valve 19, the flow of oil from the solenoid valve 29 through the second conduit 27 into the piston rod side chamber 18 is stopped, the piston 16 cannot rise, and the movable sheave block. 2 and the lower frame 3 are integrated. The solenoid valve 29 may be closed by inserting the closing switch 34 when the movable sheave block 2 and the lower frame 3 come into contact with each other without attaching the switch 35 to this embodiment. Further, when the shells 4 and 4 are completely opened in the air, the closing switch 34 may be turned on to close the solenoid valve 29.

When the open shells 4 and 4 are landed, and the movable sheave block 2 and the lower frame 3 are integrated, if the support hanger 10 is pulled up by the crane, it can be moved via the rope 9. The sheave block 2 rises together with the lower frame 3, so that the shells 4 and 4 are grasped and closed, and the state shown in FIG. 1 is obtained. Further, if the support hanger 10 is pulled up, the entire grab bucket is hung in the air.

Therefore, when the opening switch 33 of the radio signal transmitter 32 is turned on and the solenoid valve 29 is opened, the shells 4 and 4 are opened and the lower frame 3 is lowered to drop an object such as a loose object as described above. Let The button 36 is restored to the protruding state by the lowering of the lower frame 3. At this time, if the shells 4 and 4 cannot be fully opened due to space limitations, etc., the closing switch 34 is turned on when the shells 4 and 4 are partially opened as shown by the chain line in FIG. The valve 29 may be closed, and the valve can be stopped at a desired opening angle.

FIG. 8 shows an essential part of another embodiment of the present invention. The solenoid valve 29 is opened only while the wireless signal receiver 28 is receiving the open signal, and the open signal is output. It closes when it does not receive the signal, and does not have the switch 35 described in the previous embodiment. Further, the switch 39 of the wireless signal transmitter 32 transmits an open signal by pressing a button and releases the signal by releasing it. To cut off. Except for the above points, this other example has the same structure as the previous example.

In the case of this other example, as shown in FIG. 1, when the shells 4 and 4 are closed in the air, that is, when the solenoid valve 29 is closed, the button of the switch 39 is pressed to send an open signal. Then, the solenoid valve 29 is opened, and the button of the switch 39 is kept pressed. Here, the shells 4 and 4 are opened and the lower frame 3 is lowered. When the shells 4 and 4 are completely opened, the switch button 39 is released to stop the transmission and the solenoid valve 29 is closed. Next, the open shells 4 and 4 are landed, and then the movable sheave block 2 is lowered. When the solenoid valve 29 is closed, the oil in the piston rod side chamber 18 cannot pass through the check valve 19 due to the check valve 19 of the piston 16, and the piston 16 cannot move up and down, but when the piston 16 moves down. The oil in the cylinder head side chamber 17 can pass through the check valve 19. Therefore, even when the solenoid valve 29 is closed, the piston 16 in the position shown by the chain line in FIG. 8 smoothly descends together with the piston rod 13, and the oil equivalent to the volume of the piston rod 13 is sent to the oil tank 22. The solenoid valve 29 may not be closed when the shells 4 and 4 are completely opened in the air, and the button of the switch 39 may be released after the contact between the movable sheave block 2 and the lower frame 3 to close the solenoid valve 29.

After the contact between the movable sheave block 2 and the lower frame 3, the solenoid 16 is closed and the check valve 19 prevents the piston 16 from moving up. As in the previous embodiment, the movable sheave block 2 and the lower frame 3 are separated from each other. After that, the shells 4 and 4 are gripped and closed, lifted up into the air, and opened in the air as in the previous embodiment. When opening in the air, the button of the switch 39 is kept pressed to open the solenoid valve 29. When it is desired to stop the switch at a desired opening angle, the button of the switch 39 is released to close the solenoid valve 29.

According to the above embodiment, the opening and closing signals may be instantaneous, the electricity consumption of the radio signal transmitter and the receiver may be small, and the radio disturbance may occur during the opening and closing of the shell. Even if such a problem occurs, it does not hinder the opening and closing of the solenoid valve, and there is no risk that the opening and closing action of the shell will stop. Further, when the switch 35 is provided, the movable sheave block and the lower frame can be automatically integrated, which simplifies the labor.

According to another embodiment, the switch for closing the solenoid valve and its wiring due to the contact between the movable sheave block and the lower frame are not required, and the cost can be reduced accordingly. The opening and closing of the solenoid valve described above may be performed remotely by wire.

[0021]

[Effect of the device]

 According to the invention of claim 1, the movable sheave block and the lower frame can be separated and integrated by only opening and closing the solenoid valve, and a claw and a claw engaging piece are not required, and the structure is simple. Moreover, there is no inconvenience due to wear of the locking part, and it can withstand long-term use. Also, since the lower frame and the movable sheave block are connected by the cylinder and piston rod, the movable sheave block can be accurately moved up and down without a guide shaft, and since it also has a cushioning function, there is no need for a hydraulic shock absorber as a separate component. Since the number of parts is small, the structure can be greatly simplified, it can be provided at low cost, and since the check valve is formed on the piston itself, the piston can be smoothly lowered.

According to the second aspect of the invention, in addition to the above effect, the shell can be opened at a desired speed.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention and is a front view of a shell in a closed state.

FIG. 2 is a side view of the above.

FIG. 3 is a front view showing a state in which a shell is opened in the above.

FIG. 4 is a side view showing a state where a part of the above members are removed.

FIG. 5 is an enlarged side view with a partial cutaway of a main part of the above.

FIG. 6 is a sectional view taken along line AA.

FIG. 7 is a perspective view showing a state where the sheave and the rope are wound around each other.

FIG. 8 is a partially cutaway side view of an essential part showing another embodiment of the present invention.

[Explanation of symbols]

 2 Movable sheave block 3 Lower frame 4 Shell 12 Hydraulic cylinder 13 Piston rod 16 Piston 17 Cylinder head side chamber 18 Piston rod side chamber 19 Check valve 22 Oil tank 25 First conduit 26 Third conduit 27 Second conduit 29 Solenoid valve 38 Valve

Claims (2)

[Scope of utility model registration request] 1. A shell is closed by integrally raising a movable sheave block separate from the lower frame to a lower frame connected to the shell, and the lower frame is separated from the movable sheave block and lowered. In the grab bucket that opens the shell by
A hydraulic cylinder is fixed to the lower frame, a piston rod is fixed to the movable sheave block, a check valve is formed on the piston, and a cylinder head side chamber and an oil tank are connected via a first conduit. The solenoid valve and the piston rod side chamber are connected via two conduits, the solenoid valve and the cylinder head side chamber are connected via a third conduit, and the oil tank and the solenoid valve are attached to the lower frame. Grab bucket characterized by. 2. The glove bucket according to claim 1, wherein a valve for adjusting the opening speed of the shell is interposed in the middle of the second conduit connecting the solenoid valve and the piston rod side chamber.