JPS62280196A - Mast push-up device for climbing 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 (Field of Industrial Application) The present invention relates to a mast hoisting device using a wire rope in a ground hoisting type climbing crane.

(Prior art) Ground-lifting type climbing cranes that have a lifting device that raises and lowers a mast lifting frame via a wire rope wound by a climbing winch usually use a 1-speed climbing winch. . Therefore, climbing can be done both when the mast is raised, that is, when it is loaded, and when the mast has been raised and the lifting frame is lowered to attach the next unit mast, that is, when it is unloaded. The problem was that the winch could only be operated at the same speed, which increased the time required to raise the mast. Also,
If an attempt is made to shorten the climbing time in this state, a motor with a large capacity capable of raising and lowering the rope at high speed must be used as the motor for driving the climbing winch, which is uneconomical.

On the other hand, if you look at the output state of the climbing winch,
When the mast is fixed to the lifting frame (when loaded), the output is close to the rated output, but when the mast is not fixed to the lifting frame, the work is far less than the rated output, and the efficiency is low. It's bad.

For this reason, the inventor of the present invention has developed a system that detects the position of the mast fixing pin of the lifting frame by using a limit switch to determine whether or not it is in a loaded state, and allows high-speed operation if it is not in the loaded state. Although a control circuit for a climbing winch motor was constructed, there was a problem in that the operation was uncertain when the fixing pin was located halfway.

(Problems to be Solved by the Invention) In view of the above-mentioned problems, an object of the present invention is to enable the lifting frame to be raised and lowered at high speed in an unloaded state, thereby shortening the time required for climbing. An object of the present invention is to provide a mast raising device for a climbing crane having a structure capable of reducing the capacity of a driving motor of a climbing winch, and also capable of reliably detecting a loading state for speed switching. .

(Means for Solving the Problems) In order to achieve this object, the present invention provides a support mast installed on the ground with an elevating frame that is lifted and lowered by a climbing winch via a wire rope, and a climbing crane attached to the elevating frame. In a mast lifting device for a climbing crane that raises a mast with a fixed mast, the climbing winch is equipped with a pole-convertible electric motor capable of high-speed and low-speed switching operation as a driving device for the climbing winch, and the wire attached to the supporting mast is equipped with a One of the rope sheaves is attached via a spring that deflects as the rope tension increases, and a striker that is displaced according to the deflection of the spring and a limit switch that is operated by the striker are provided, and the contact of the limit switch is connected to the load. The present invention is characterized in that the control circuit is incorporated in the control circuit of the electric motor so that high-speed operation of the electric motor is prohibited when the rope tension increases.

(Example) First, the overall configuration of an example of the present invention is shown in Figures 4 to 10.
This will be explained using figures. As shown in FIG. 4, the mast 1 on which the crane body 10 is mounted has a plurality of crown squares) la to 1.
It is constructed by adding n using the mast raising device 11 on the ground. The mast raising device 11 is the fifth
As shown in FIG. 6, it has a support mast 2 and an elevating frame 4 having a guide collar 13 that rolls along a guide rail 12 provided on the support mast 2. As shown in FIGS. 5 and 7, the elevating device for the elevating frame 4 moves the wire rope 5, which is wound up and unrolled by the climbing winch 3, onto the upper frame 2A at the top of the support mast 2. It is constructed by hanging between the attached sheave block 14.16 and the sheave block 15.17 attached to the lifting frame 4. Figures 8 to 1
As shown in FIG. 0, the mast 1 can be fixed to the lifting frame 4 by inserting the bolt pin 6 attached to the lifting frame 4 into the bolt hole 18 provided in the unit mast 11.

To raise the mast 1, insert the bolt pin 6 into the bolt hole 18 of the lowest unit mast 11, fix the mast 1 to the lifting frame 4, and wind the wire rope 5 with the climbing winch 3 to raise and lower the mast l. Raise it together with frame 4. As shown in FIGS. 5 and 6, when the elevating frame 4 rises sufficiently to create a space under the mast 1 in which the additional unit mast 1j can be inserted, the unit mast 1j
is inserted and connected to the unit mast 11 fixed to the lifting frame 4. In this way, when the next unit mast 1j is connected and the crane main body 10 is supported by the mast l, the bolt pin 6 is pulled out and the mast 1 is connected.
Separate the lifting frame 4 from the lifting frame 4. Next, lower the lifting frame 4 with no load, and when it descends to the lowest point, insert the bolt pin 6 into the bolt hole 18 of the next unit mast again.
Repeat this action 1. Continue climbing.

Next, the main parts of the present invention will be explained with reference to the embodiments shown in FIGS. 1 to 3. 7 is a limit switch attached to the upper frame 2A of the support mast 2 according to the present invention; 23 is a force that opens and closes the switch contact by pressing against and separating from the operating rod 7a of the limit switch 7; is ring-shaped, and is slidably fitted to a rod 21 inserted into a hole 25 provided in the upper frame 2A so as to be vertically movable, and is a support for a spiral spring 22 attached to the rod 21 via a cylinder 26. is also used as a board. rod 2
A thread groove z7 is formed in the upper part of 1, and the thread vIt27
A nut 28 for adjusting the position of the striker 23 is screwed into. Reference numeral 20 denotes a bracket 2 fixed to the upper frame 2A.
The lower end of the rod 21 is rotatably connected to the tip of the link 20 by the pin 31, and a lobe attached to the support mast 2 is attached to the middle part of the link 20. In the fifth hanger, a hanger 19 of a sheave 24 (see FIG. 7), which is one of a plurality of sheaves for turning, is suspended by a pin 32.

By adjusting the spring force of the spring 22 and the position of the striker 23, the tension of the rope 5 increases when the lifting frame 4 is loaded, and as a result, the spring 22 deflects as shown in FIG. The striker 23 is configured to separate from the operating rod 7a of the limit switch 7 and its contact opens.

Fig. 3 shows a limiting circuit of the electric motor 9 for driving the climbing winch 3 incorporating the limit switch 7, and the electric motor 9 is a limit conversion motor whose speed can be switched between high and low speeds by changing the number of poles. Reference numeral 8 designates operating switches PB 1 and PH 1 for instructing the motor 9 to rotate in the winding direction and unwinding direction of the wire rope 5 (that is, in the ascending direction and descending direction of the elevating frame 4, respectively). and operation switch PB3゜PH4 for commanding high-speed rotation and low-speed rotation, respectively, and A:6-CFI, CRI, CX,, CL,
CF, CR, CFX, and CRX are lJ+z-, and the symbols consisting of lowercase letters of the alphabet and the symbols with a or b attached to them are the contacts of each relay.

In this circuit, when the mast l is fixed to the lifting frame 4 by inserting the #J bolt pin 6 into the bolt hole 18 and raising the mass l = 1, the tension of the lobe 5 is large, so the spring 22 is in a bent state as shown in Fig. 2, so the striker 23 is in a state away from the operating rod 7a of the limit switch 7, and since the contact point of the limit switch 7 is open, the relay CX rotates at high speed. Regardless of the command operation, the a contact C is not energized.
1d remains open, the relays CFX and CRX for high-speed ascent and high-speed descent are not energized, and motor 9
cannot perform high-speed rotation.

On the other hand, the relay C1 is a low-speed rotation command operation switch FB.
4, the relay Cx is energized and energized via the b contact cxb, so the a contact ala of the relay C1 is closed, and in this state, the operating switch FBI or P
When H1 is operated, relay CFI or CRI is energized and these a contacts cfla or aria are closed, and relay CF or CR is energized and contacts cf or cr are closed, so motor 9 moves lift frame 4 at low speed. Rotate in the direction or down direction. That is, in a loaded state in which the mast 1 is fixed to the lifting frame 4, the lifting frame 4 can only be moved up and down at a low speed.

On the other hand, when the load is empty, that is, when the bolt pin 6 is pulled out, the lifting frame 4 is moved by the force of the spring 22.
The link 20 and rod 21 hanging down are pushed up, and the striker 23 pushes up the operating rod 7a of the limit switch 7, so that the contact point of the limit switch 7 is closed. In this state, the operation when operating the operation switch FB4 for low speed rotation command and operating the operation switch FBI or PH1 for ascending or descending is as described above.

When operating switch FB3 for high-speed rotation command is operated, relay CX is energized and its a contact CIa is closed. If operating switch FBI or PH1 is operated in this state, relay CFI or CRI is energized and these a contacts are closed. c.
fla or crla closes, relay CFX or CRX
is energized and the contact cfx or cr! is closed, the motor 9 rotates at high speed in the direction of raising or lowering the lifting frame 4.

That is, when the mast 1 is not fixed to the lifting frame 4, that is, when there is no cargo, either high speed or low speed can be selected.

Therefore, during the lowering operation of the lifting frame 4 in an unloaded state, the climbing winch 3 can be operated at high speed to shorten the climbing time, and the capacity of the climbing winch drive motor 9 for this purpose can be reduced to the necessary minimum. You can choose to. When the crane is lowered by sequentially separating and pulling out the unit masts, the operation is just the opposite, and the time required for hoisting the empty load of the lifting frame 4 can be shortened.

In addition, in FIG. 3, for example, the low speed rotation command operation switch FB4 and the b of the relay C1 connected to the relay Cx.
If you eliminate the contact clb and short-circuit the parts where these were provided, you only need to press the operation switch PB3 when performing high-speed ascent and descent, and there is no need to press the speed selection operation switch for low-speed ascent and descent. It goes without saying that the specific configuration of the operating circuit, such as the ability to do so, can be changed in various ways without departing from the gist of the present invention.

(Effects of the Invention) According to the present invention, it is possible to perform high-speed lifting and lowering when the lifting frame is unloaded, so the climbing time and the time for lowering the unloaded load can be shortened. Since high-speed lifting and lowering is possible only when the climbing winch is in the correct position, there is no need to increase the capacity of the climbing winch drive motor, and the capacity can be kept to the minimum required.

Furthermore, in the present invention, since the loading state is directly detected by the spring, the loading state can be reliably detected, and switching between high speed and low speed due to loading and unloading can be performed reliably. .

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 shows an example of the mounting structure of a limit switch according to the present invention in an unloaded state, FIG. 2 shows the same in a loaded state, and FIG. 3 4 is a diagram showing an example of a control circuit for an electric motor for driving a climbing winch according to the present invention, FIG. 4 is an overall diagram showing an example of a ground-lifting climbing crane, and FIG. 5 is a diagram showing a mast lifting device of the crane shown in FIG. 4. A front view, FIG. 6 is a view taken along the line A-A in FIG. 5, FIG. 7 is a diagram showing an example of the wiring of the mast lifting device, and FIG. FIG. 9 is a plan view showing the connection structure of FIG. 8, and FIG.
It is a CC sectional view of the figure.

Claims (1)

[Claims] In a climbing crane mast raising device, a lifting frame that is lifted and lowered by a climbing winch via a wire rope is attached to a support mast installed on the ground, and the mast of the climbing crane is fixed to the lifting frame to raise the mast. A winch drive device is equipped with an electric motor of the pole number convertible type capable of high-speed and low-speed switching operation, and one of the wire rope sheaves attached to the support mast is attached via a spring that bends as the rope tension increases. A striker that is displaced according to the deflection of the spring and a limit switch operated by the striker are provided, and the contact point of the limit switch is connected to the electric motor so that high-speed operation of the electric motor is prohibited when the rope tension increases under load. A mast raising device for a climbing crane, characterized in that the device is incorporated into the control circuit of a climbing crane.