JPH10279284A - Jib type crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent safety standard from moving to a dangerous side even if a main mode is selected while an auxiliary jib overhangs. SOLUTION: This crane has a main jib which hoists a first load, an auxiliary jib which is provided in such a manner that it can overhang from a tip of the main jib and can be stored freely, is overhung, and hoists a second load, a selection means 4 which selects either of a main mode Mm which works in the main jib and an auxiliary mode Ms which works in the auxiliary jib, a first detection means 5 which detects the first load, and a moment limiter 3 which receives first load information W1 at the time of the main mode Mm and stops work when the first load exceeds reference allowable load. In this case, it has a second detection means 6b which detects the overhang of the auxiliary jib and a moment limiter which reduces the reference allowable load of the main mode Mm by a predetermined amount when it receives the overhang information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a jib crane.

[0002]

2. Description of the Related Art There are various types of cranes, such as a gate type and a column type. Among them, for example, there is a so-called jib type crane of a mobile type and a column type. This jib crane has a main jib 1 and an auxiliary jib 2 as shown in FIG. The main jib 1 expands and contracts to suspend the first load W1, and the auxiliary jib 2 is provided so as to be able to protrude from the tip of the main jib 1 and to be retractable, and is extended to suspend the second load W2. Therefore, this crane has a main mode Mm for working using the main jib 1 and a sub-mode Ms for working using the auxiliary jib 2. Therefore, this crane is equipped with the main and sub mode Mm, M
There is provided a selection means such as a switch which is designated and input by an operator in order to select s. In the main mode Mm, for each length of the main jib 1, for example, as shown in FIG. Further, in the sub mode Ms, for each length of the main jib 1 and each length of the auxiliary jib 2, for example, as shown in FIG. 14, a curved allowable load Ws is set with respect to the undulation angle θ of the main jib 1. You. And
Each allowable load Wm, Ws is regarded as a safety standard for crane work, and work on a dangerous side exceeding the safety standard is prohibited. For this reason, the jib-type crane is set in advance in the main / sub mode Mm, Ms
, And the actual loads in each mode are detected by the first detecting means for detecting the first and second loads W1 and W2, and the actual loads correspond to the respective allowable loads Wm and Ws. When the load exceeds Wm and Ws, a moment limiter such as a microcomputer that stops the work on the dangerous side is provided.

[0003]

However, according to the above prior art, there are the following problems. For example, suppose that despite the extension of the auxiliary jib 2, the operator forgets to select it and selects the main mode Mm and inputs it to the moment limiter via the selection means. At this time, the allowable limit Wm of the existing main mode Mm is set by the moment limiter. However, since the allowable load Wm is a state in which the auxiliary jib 2 is stored, the safety standard of the moment limiter moves to the dangerous side. This is because, when the auxiliary jib 2 is extended, the allowable load in the main mode Mm becomes smaller than Wm by a predetermined amount w in consideration of the weight of the auxiliary jib 2 and the like.

[0004] In view of the above-mentioned problems of the prior art, an object of the present invention is to provide a jib crane in which the safety standard does not move to the dangerous side even if the main mode is selected while the auxiliary jib is extended. .

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, a jib crane of the present invention firstly comprises a main jib for suspending a first load, and a jib which can be freely extended from the tip thereof. Selection means for selecting any of a supplementary jib which is provided so as to be retractable and is extended and suspends the second load, a main mode for working using the main jib, and a sub mode for working using the supplementary jib And a first detecting means for detecting a first load; and receiving selection information from the selecting means and in a main mode, the first
A jib crane having a moment limiter for stopping the operation when the first load exceeds the reference allowable load in response to the first load information from the detecting means; And a moment limiter for updating the reference allowable load in the main mode by a predetermined amount when receiving the overhang information from the detecting means.

According to the first aspect, when the moment limiter receives the overhang information, the moment limiter sets the allowable load of the main mode in a state where the auxiliary jib is overhanging. Therefore,
Even if the main mode is selected while the auxiliary jib is extended, the safety standard of the moment limiter does not move to the dangerous side. That is, safe work can be performed.

Second, a main jib for suspending the first load, an auxiliary jib which is provided on the main jib so as to be able to protrude from the tip thereof and to be stowable, and which is protruded to suspend the second load, and a main jib are used. Selecting means for selecting one of a main mode for performing the work performed and a sub-mode for performing the work using the auxiliary jib, first detecting means for detecting the first load, and receiving selection information from the selecting means. When this is the main mode, it is detected that the auxiliary jib has been stored in the jib crane having the moment limiter for stopping the work when the first load exceeds the reference allowable load upon receiving the first load information from the first detecting means. And a moment limiter for updating the main mode reference allowable load by a predetermined amount when the storage information is not received from the third detection unit.

The phrase "when the storage information is not received" in the second invention is a paraphrase of the phrase "when the overhang information is received" in the first invention. Therefore, the second invention has the same effect as the first invention.

Third, there is provided a jib crane having a main jib for suspending a first load, and a supplementary jib which is provided on the main jib so as to be protrudable and retractable from the tip thereof and protruded to suspend a second load. Second detecting means for detecting that the supplementary jib has been extended, third detecting means for detecting that the supplementary jib has been stored, and receiving or simultaneously receiving each information from the second and third detecting means. And determining means for outputting, to the outside, meaning information indicating that "the second and third detecting means are abnormal" when there is no such information.

It is impossible to receive each information from the second and third detecting means at the same time. Therefore, if this occurs, the second and third detecting means are obviously abnormal. on the other hand,
Not receiving the information at the same time indicates that the information is being extended or stored. Therefore, in this case, it is dangerous to easily connect to the existing operation. The determination means makes this determination first. Then, the determination means may input the above-mentioned meaning information to, for example, a moment limiter, and cause the moment limiter to stop the work. However,
The determination means may be the moment limiter itself.
As described above, according to the second aspect, even when the second and third detection means are abnormal (that is, when the moment limiter cannot correctly set the reference allowable load), it is possible to prevent the dangerous operation from occurring. Further, when a moment limiter is not provided, it is possible to inform the operator of the abnormality of the machine by inputting to the display means or the alarm means so that the operator does not know and work on the dangerous side.

Fourth, a main jib that suspends the first load, a supplementary jib that is provided on the main jib so as to be protrudable and retractable from the tip thereof, and that is extended and suspends the second load, and a main jib that uses the main jib. In a jib crane having a mode and a selecting means for selecting one of the sub-modes using the auxiliary jib, a second detecting means for detecting that the auxiliary jib is overhanging, and receiving selection information from the selecting means. When this is the main mode, and this is the overhang after receiving the overhang information from the second detecting means,
Determining means for outputting to the outside meaning information indicating that the operation is incorrect.

According to the fourth aspect of the invention, it is possible to input the meaning information to, for example, a moment limiter and stop the work by the moment limiter. However, the determination means may be the moment limiter itself. In this way, even if the main mode is selected while the auxiliary jib 2 is extended, or vice versa, it is possible to prevent the danger-side work from occurring. Further, when a moment limiter is not provided, it is possible to inform the operator of an erroneous operation by inputting to the display means or the alarm means so that the operator does not know and work on the dangerous side.

Fifth, a main jib for suspending the first load, a supplementary jib which is provided on the main jib so as to be able to protrude from the tip thereof and to be retractable, and which is protruded to suspend the second load, and a main jib are used. In a jib crane having selection means for selecting one of a main mode and a sub mode using an auxiliary jib, a third detection means for detecting that an auxiliary jib is stored, and receiving selection information from the selection means. This is the main mode and the third
When the storage information is not received from the detection means, there is provided a determination means for outputting meaning information indicating that "the operation is incorrect" to the outside.

The phrase "when the storage information is not received" in the fifth invention is a paraphrase of the phrase "when the extension information is received and this is an overhang" in the fourth invention. Therefore, the fifth invention has the same effect as the fourth invention.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. For example, in a mobile crane, as shown in FIG. 1, an upper revolving structure B is mounted on a lower traveling structure A so as to be freely rotatable, and a main jib 1 which is extendable and retractable is fixedly mounted on the upper revolving structure B. On the side wall 1a of the main jib 1, an auxiliary jib 2 indicated by a solid line in FIG. Then, the movable crane works by suspending the first load W1 on the main jib 1 while turning the upper swing body B to raise and lower and expand and contract the main jib 1. On the other hand, as shown by the two-dot chain line, the auxiliary jib 2 in FIG. 1 is extended from the tip of the main jib 1 and the second jig 2 suspends the second load W2. As described above, there are two operation modes, the main mode Mm for performing the operation using the main jib 1 and the sub mode Ms for performing the operation using the auxiliary jib 2. 13 and 1
As described with reference to FIG. 4, the work modes have different allowable loads Wm and Ws, respectively. For this reason, the mobile crane stores in advance the allowable loads Wm and Ws corresponding to the main and sub modes Mm and Ms, respectively, and sets the allowable load according to the operation mode selected by the input of the operator. Second
An actual load in each mode is detected by first detection means for detecting the loads W1 and W2. When the actual load exceeds the allowable load Wm or Ws corresponding to each of the modes, a microcomputer or the like which stops the work on the dangerous side. Is provided.

The moment limiter 3 is shown in FIG.
As shown in (1), a selection means 4 such as a switch for selecting a work mode, a first detection means 5 for detecting an actual load, a second detection means 6b for detecting overhang of the auxiliary jib 2, and a storage of the auxiliary jib 2 On the input side. On the other hand, the allowable load (for example, FIG.
And a storage means 7 for storing the curved Wm of FIG. 14 and the curved Ws of FIG. 14, and a display means 8, an alarm means 9, and a work restriction means 10 on the output side. Information is received from the selection means 4, the detection means 5, 6a, 6b, and the storage means 7, and when the actual load exceeds the allowable load, a signal is input to the display means 8, the alarm means 9, and the work restriction means 10, and the display means 8. The alarm means 9 is caused to warn, and the work restricting means 10 is stopped from working on the dangerous side.

The storage state of the auxiliary jib 2 will be described with reference to FIGS. 3, which is a view taken along the line Z1 of FIG. 1, and FIG. 4, which is a partial sectional view of FIG. The main jib 1 has a bracket 11 having holes 11a and 11b on the left and right at its tip, a bracket 12 fixed at a front portion of the side wall 1a, and a bracket 13 having a stopper 13a at a rear portion. . The auxiliary jib 2 is provided with a yoke 21 having holes 21a and 21b on the left and right at its base end (in front of the vehicle body) and fixed to the side wall 1a of the main jib 1.
A bracket 22 is fixedly provided at a rear portion (front of the vehicle body) of the side wall 2a, and a bracket 23 is fixedly provided at a front portion (rearward of the vehicle body). The front portion (rear side of the vehicle body) of the side wall 2a is
a, while being placed on the bracket 13, the brackets 12 and 22 are connected by pins 24, and the brackets 13 and 23 are connected by pins 25. Pins 26 and 27 are inserted into the holes 21 a and 21 b of the yoke 21. Pins 24, 25, 26 and 27 are respectively connected to chain 2
4a, 25a, 26a and 27a are connected to the auxiliary jib 2 to prevent loss and dropout. Third detection means 6 a, such as a proximity switch, is fixed to the bracket 13 near the pin 25 and is electrically connected to the moment limiter 3. In this way, the auxiliary jib 2 is stored in the main jib 1. In this state, the third detecting means 6a detects the proximity to the pin 25 and inputs the storage signal S2 to the moment limiter 3.

The complementary jib 2 shown in a two-dot chain line in FIG.
The extended state of the auxiliary jib 2 will be described with reference to FIGS. Below the hole 11b at the tip of the main jib 1, a second detecting means 6b such as a proximity switch is fixed to the bracket 11 via the bracket 14. The second detecting means 6b is electrically connected to the moment limiter 3. 3 and 4, the pins 24, 25, 26, and 27 are removed from the stored auxiliary jib 2 and the auxiliary jib 2 is moved forward by a moving means (not shown), so that the base 21a of the auxiliary jib 2 has a hole 21a. To the hole 11a at the tip of the main jib 1 and the pin 26 is inserted. And
The auxiliary jib 2 is turned around the pin 26 from the rear to the front using a rotating means (not shown). Then, the hole 21b at the base end of the auxiliary jib 2 is aligned with the hole 11b at the tip of the main jib 1, and the pin 27 is inserted. Thus, the extension of the auxiliary jib 2 is completed.
At this time, the inserted pin 27 approaches the second detecting means 6b, and the second detecting means 6b detects this approach and inputs the overhang signal S1 to the moment limiter 3. In this extended state, the pin 25 which was close to the third detecting means 6a at the time of storage moves forward together with the connected auxiliary jib 2 so that the third detecting means 6a sends the stored signal to the moment limiter 3. S2 has not been entered.

Next, a first control example of the moment limiter 3 will be described with reference to a flowchart shown in FIG. The moment limiter 3 stores allowable loads Wm and Ws corresponding to the main and sub modes Mm and Ms, and a predetermined amount w for reducing the allowable load of the main mode Mm when the auxiliary jib 2 is extended. 01). The selection information Mm or Ms from the selection means 4 is received, and the overhang information S1 from the second detection means 6b and the storage information S2 from the third detection means 6a can be received (02). It is determined whether or not the overhang information S1 is present (03). When the overhang information S1 is received, the existing allowable load Wm of the main mode Mm is reduced by a predetermined amount w as shown in FIG. Update the allowable load of.
In addition, for example, a curve-like update allowable load (W
mw) may be stored and read (04). When the overhang information S1 is not received, the allowable load Wm of the existing main mode Mm is set (05). Next, the selection information Mm or Ms is determined (06), and in the case of the main mode Mm, the original operation of the moment limiter 3 that functions so that the actual load W1 does not exceed the allowable load is started (07). Secondary mode M
If it is s, the allowable load Ws is set and the original operation is started (08).

In this way, when the auxiliary jib 2 is extended, the moment limiter 3 is set to the allowable load (Wm-w) of the main mode Mm in a state where the auxiliary jib 2 is extended. Therefore, the main mode M is maintained while the auxiliary jib 2 is extended.
Even if m is selected, the safety standard of the moment limiter 3 does not move to the dangerous side.

Subsequent to step (02) of the first control example, a subroutine is provided to determine whether or not the overhang and storage information S1 and S2 exist (09), and the overhang information S1 and the storage information S2 are simultaneously received. At the same time, or when not receiving at the same time, a signal is input to the display means 8, the alarm means 9, and the work restriction means 10, and the display means 8 and the alarm means 9 are alerted that "the detection means 6a and 6b are abnormal". The work restricting means 10 can also stop the work (10).

In this way, even if the detecting means 6a, 6b is abnormal (that is, the moment limiter cannot set the reference allowable load correctly), it is possible to prevent the operation on the dangerous side from occurring.

In the first control example, the judgment items in step (03) may be replaced with those shown in FIG.
That is, the presence or absence of the storage information S2 is determined (031). When the storage information S2 is not received, the existing allowable load Wm of the main mode Mm is reduced by a predetermined amount w as shown in FIG. Is updated (04). When the storage information S2 is received, the allowable load W of the existing main mode Mm
m is set (05).

Even in this case, substantially the same effect as before replacement can be obtained.

Next, a second control example will be described with reference to the flowchart shown in FIG. The moment limiter 3 is
Allowable load Wm, W corresponding to each of main and sub modes Mm, Ms
s is stored (01). Selection information M from selection means 4
m or Ms is accepted, and the overhang information S1 from the second detection means 6b and the storage information S2 from the third detection means 6a can be accepted (02). The selection information Mm or Ms is determined (03), and if it is the main mode Mm, the allowable load Wm of the main mode Mm is set (04). Next, the presence or absence of the overhang information S1 is determined (05), and when the overhang information S1 is received, a signal is input to the display means 8, the alarm means 9, and the work restriction means 10, and the display means 8, the alarm means 9 Is warned that the operation is wrong, and the work restricting means 10 stops the work (06). If it is the sub mode Ms, the allowable load Ws is set (07), and the original operation of the moment limiter 3 that functions so that the actual load does not exceed the allowable load is started (08).
When the overhang information S1 is not received, the set allowable load Wm is set.
Then, the original operation is started (08).

In this way, even if the main mode Mm is selected while the auxiliary jib 2 is extended, and vice versa, it is possible to prevent the operation on the dangerous side from occurring.

In the second control example, the judgment items in step (05) may be replaced with those shown in FIG. That is, the presence or absence of the storage information S2 is determined (051). When the storage information S2 is not received, the display unit 8, the alarm unit 9,
A signal is input to the work restricting means 10, and the display means 8 and the warning means 9 are warned that "the operation is incorrect", and the work restricting means 10 stops the work (06). Storage information S
2, the original operation is started with the set allowable load Wm (08).

Even in this case, substantially the same effect as before replacement can be obtained.

The subroutine described in the first control example and the determination function of the moment limiter 3 described in the second control example may be constituted separately. In this case, application to a jib crane having no moment limiter 3 is easy.

[Brief description of the drawings]

FIG. 1 is a side view of an embodiment.

FIG. 2 is a block diagram of a moment limiter.

FIG. 3 is a view as viewed from Z1 in FIG. 1;

FIG. 4 is a partial sectional view of FIG. 3;

FIG. 5 is a view as viewed from Z2 in FIG. 1;

FIG. 6 is a sectional view of FIG. 5;

FIG. 7 is a flowchart of a first control example.

FIG. 8 is a graph of an example of updating the allowable load in the main mode.

FIG. 9 is a part of a flowchart showing another mode in the first control example.

FIG. 10 is a flowchart of a second control example.

FIG. 11 is a part of a flowchart showing another mode in the second control example.

FIG. 12 is a side view showing the overhang of the conventional main jib and auxiliary jib.

FIG. 13 is a graph showing an example of an allowable load in a conventional main mode.

FIG. 14 is a graph showing an example of a permissible load in a conventional sub mode.

[Description of Signs] 1 ... Main jib, 2 ... Complementary jib, 3 ... Moment limiter, 4
... selecting means, 5 ... first detecting means, 6a ... third detecting means,
6b: second detection means, 7: storage means, 8: display means, 9
... alarm means, 10 ... work restriction means, 11, 12, 13,
14: Bracket, 21: Yoke, 22, 23: Bracket, 24, 25, 26, 27: Pin.

Claims (5)

[Claims] (A) a main jib for suspending a first load; and (b) a main jib is provided so as to protrude from its tip and to be retractable,
A supplementary jib overhanging and suspending the second load, and (c) a selection means for selecting one of a main mode for working using the main jib and a sub mode for working using the supplementary jib, d) first detection means for detecting the first load, and (e) receiving the selection information from the selection means and in the main mode, receiving the first load information from the first detection means and setting the first load to a reference tolerance. In a jib crane having a moment limiter that stops work when a load is exceeded, (f) second detecting means for detecting that the auxiliary jib is overhanging, and (g) receiving overhang information from the second detecting means. And a moment limiter which updates the reference allowable load of the main mode by a predetermined amount. 2. A main jib for suspending a first load, and (b) a main jib which is provided so as to be able to protrude from its tip and to be retractable,
A supplementary jib overhanging and suspending the second load, and (c) a selection means for selecting one of a main mode for working using the main jib and a sub mode for working using the supplementary jib, d) first detection means for detecting the first load, and (e) receiving the selection information from the selection means and in the main mode, receiving the first load information from the first detection means and setting the first load to a reference tolerance. In a jib crane having a moment limiter that stops work when a load is exceeded, (f) third detection means for detecting that the auxiliary jib is stored, and (g) when no storage information is received from the third detection means. And a moment limiter for updating the main mode reference allowable load by reducing it by a predetermined amount. (3) a main jib for suspending the first load, and (b) a main jib which is provided so as to protrude from its tip and to be retractable,
In a jib crane having an auxiliary jib that is extended and suspends a second load, (c) second detecting means for detecting that the auxiliary jib has been extended, and (d) second detecting means for detecting that the auxiliary jib has been stored. And (e) when the respective information is received simultaneously or not simultaneously from the second and third detecting means, the meaning information indicating that "the second and third detecting means are abnormal" is output to the outside. And a determination means for outputting the output to the jib. And (a) a main jib for suspending the first load, and (b) a main jib which is provided so as to protrude from its tip and to be stowable,
In a jib crane that has an auxiliary jib overhanging and suspending a second load, and (c) a main mode using a main jib, and a selection unit that selects any of a sub-mode using an auxiliary jib,
(d) second detecting means for detecting that the auxiliary jib has been overhanged;
(e) When the selection information is received from the selection means and this is the main mode, and when the overhang information is received from the second detection means and this is the overhang, the semantic information indicating that "the operation is incorrect" is output to the outside. And a determination means for outputting the output to the jib. 5. A main jib for suspending a first load, and (b) a main jib is provided on the main jib so as to be able to protrude from its tip and to be retractable,
In a jib crane that has an auxiliary jib overhanging and suspending a second load, and (c) a main mode using a main jib, and a selection unit that selects any of a sub-mode using an auxiliary jib,
(d) third detecting means for detecting that the auxiliary jib has been stored;
(e) When receiving the selection information from the selection means and this is the main mode, and when receiving no storage information from the third detection means,
A jib crane comprising: a judging means for outputting, to the outside, meaning information indicating that the operation is incorrect.