JPS6143833Y2 - - Google Patents

Description

[Detailed Description of the Invention] Cranes and the like generally employ multi-stage booms, and it is preferable that these multi-stage booms operate one after another according to a certain order. For this purpose, devices that hydraulically control sequential operation are used, but they have the disadvantage that sequential operation cannot be maintained if abnormally high pressure is generated due to frictional resistance, etc., and the overall cost is high. .

The present invention provides a sequential actuation device that allows a multi-stage boom to be extended and retracted in a predetermined order, and more particularly, an engagement device with a simple structure constituting the sequential actuation device.

An embodiment of the present invention will be explained with reference to the drawings.
As shown in Figure 1, the multi-stage boom includes a base boom 1,
It consists of an intermediate boom 2 that slides within the base end boom 1 and extends and contracts with respect to the base end boom 1, and a tip boom 3 that slides within the intermediate boom 2 and extends and contracts with respect to the intermediate boom 2, The tip of a piston rod 5 of a hydraulic cylinder 4 is pivoted 5' to the inner base of the proximal boom 1, and the tip of a cylinder barrel 6 of the hydraulic cylinder 4 is pivoted 6' to the inner base of the intermediate boom 2. Furthermore, the base of the cylinder barrel 8 of the hydraulic cylinder 7 is pivoted at the inner base of the intermediate boom 2.
At the same time, the tip of the piston rod 9 of the hydraulic cylinder 7 is pivoted 9' to the inner tip of the tip boom 3. Therefore, the hydraulic cylinder 4
The expansion and contraction of the intermediate boom 2 accompanies the expansion and contraction of the base end boom 1 , and the expansion and contraction of the hydraulic cylinder 7 accompanies the expansion and contraction of the tip boom 3 with respect to the intermediate boom 2 .

By the way, a pair of locking devices 10 and 10' are provided on the upper wall of the base of the intermediate boom 2, respectively.

The locking devices 10 and 10' will be explained below. A pair of guides 1 are provided on the upper wall of the base of the second boom 2.
1, 11' are fixed, and shafts 12, 12' are inserted into these guides 11, 11' slightly beyond the upper and lower ends of said guides 11, 11'. On the shafts 12, 12' there are locking arms 14, 14' having locking parts 13, 13' on the lower part of the shaft and on the upper part thereof, respectively. Abutment arms 15, 15' are fixed to the opposite surface of the attachment side to the intermediate boom 2, respectively. On the other hand, stoppers 16, 16' are fixed to appropriate positions on the inner surface and outer surface of the intermediate boom 2, and are biased by springs 17, 17' stretched between the ends of the locking arms 14, 14' and the intermediate boom 2. The clockwise rotation of the locking arms 14, 14' and the abutment arms 15, 15' relative to the guides 11, 11' is restricted.

By the way, at the base of the outer surface of the top wall of the tip boom 3 and the tip of the inner surface of the top wall of the base boom 1, there are locking rollers 18, 18 that can be locked to the locking portions 13, 13' of the locking arms 14, 14'. ' are fixed to the inner surface of the upper wall of the proximal end boom 1 and at the base of the outer surface of the upper wall of the distal end boom 3 are abutment rollers 19, 19' that can come into contact with the aforesaid abutment arms 15, 15'. It is fixed. Therefore, when the multi-stage boom is in the contracted state as shown by the solid line in FIG.
7' against the abutment arm 15' and the locking arm 1
4' is rotated counterclockwise, and a locking roller 18 is engaged with the locking portion 13 of the locking arm 14.

By the way, the above-mentioned abutting roller 19 and locking roller 18' are integrally fixed to the inner tip of the upper wall of the base end boom, and the details thereof will be explained with reference to FIGS. 4 and 5. Holes 20, 20' are bored in the tip of the upper wall so that a pair of rollers can be inserted therein, and above the holes is a reinforcing plate 22 having holes 21, 21' that match the holes 20, 20'. Fixed by welding. A mounting plate 23 is fixed on the reinforcing plate 22, passing through the holes 20, 21 and 20', 21', and fixing the abutting roller 19 and the locking roller 18' together.

Although not shown in detail, a locking roller 18 and an abutment roller 19' provided at the base of the outer surface of the upper wall of the tip boom 3 are also fixed to the mounting plate in the same manner.

Next, to explain the operation of this embodiment, when the multi-stage boom is in the contracted state, when a hydraulic pump (not shown) is operated and pressure oil is supplied to the extension side oil chambers of the hydraulic cylinders 4 and 7, the base of the intermediate boom 2 is The proximal boom 1 and the intermediate boom 2 are unlocked by the provided locking device 10', while the intermediate boom 2 and the tip boom 3 are secured by the locking device 10. In other words, the locking arm 14 and the locking roller 18 are engaged with the locking portion 13 of the locking arm 14, and the extension of the tip boom 3 is prevented.
First, the hydraulic cylinder 4 is extended, and the intermediate boom 2 is extended with respect to the proximal boom 1.

When the intermediate boom 2 is fully extended, the abutment arm 15
comes into contact with the abutment roller 19 and rotates counterclockwise against the spring 17, and at the same time, the locking portion 13' of the locking arm 14' faces the locking roller 18'. (Position indicated by chain line in Figure 2).

As the abutting arm 15 rotates, the locking portion 13 of the locking arm 14 is simultaneously released from the locking roller 18, so that the tip boom 3 is released from being secured. Therefore, the hydraulic cylinder 7 is then extended, and the tip boom 3 is extended. When the tip boom 3 extends,
Since the locking roller 18 and the abutting roller 19' move, the abutting arm 15' and the locking arm 14' are rotated back clockwise by the biasing force of the spring 17', and as a result, the locking arm 14' is locking roller 1
By engaging 8', the intermediate boom 2 and the proximal boom 1 are secured.

In addition, when retracting and retracting the multi-stage boom from its maximum extension state, the base end boom 1 and the intermediate boom 2 are tied together, and the engagement between the intermediate boom 2 and the tip boom 3 is disengaged. Hydraulic cylinder 4,
By supplying oil to the contraction side oil chamber of 7, the hydraulic cylinder 7 is first contracted, and the tip boom 3 is contracted into the middle boom 2. When the distal boom 3 is fully retracted, the intermediate boom 2 is then retracted into the proximal boom 1.

In this embodiment, the multi-stage boom is configured as a three-stage boom, but it may also be configured as a multi-stage boom with four or more stages, and used for sequential telescopic operation between three consecutive booms or for sequential telescopic operation of all booms. Alternatively, the telescoping operation of each boom may be performed using a system other than a hydraulic cylinder.

As described above, in the present invention, the locking roller and the abutting roller respectively correspond to the locking arm of one locking device and the abutting arm of the other locking device provided on one side of the intermediate boom. Since they are fixed together, there is no need to separately attach them to each arm, and the attachment can be done extremely easily and reliably.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is an overall side view schematically showing a multistage boom, Fig. 2 is an enlarged plan view of the locking device, Fig. 3 is a side view thereof, and Fig. 4. 5 is an enlarged plan view showing the mounting state of the abutting roller and the locking roller, and FIG. 5 is a sectional view taken along the line A--A in FIG. 4. 1... Proximal boom, 2... Intermediate boom, 3...
Tip boom, 10, 10'...Locking device.

Claims (1)

[Scope of utility model registration request] In a multi-stage boom in which one or more intermediate booms and tip booms are telescopically inserted into a base boom in sequence, a lock is independently rotatably supported on one side of an end of the intermediate boom. A multi-stage device characterized in that a locking roller and a colliding roller are integrally fixed to the inner surface of the boom end of the preceding stage or the outer surface of the boom end of the next stage, corresponding to the arm and the colliding arm, via a mounting plate. Engagement device of sequential actuation device in boom.