JP2004099242A - Tilt angle detector for extension jib - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tilt angle detector of less noises at a low cost, as to a tilt angle detector for detecting the tilt angle of an extension jib 12 used by being supplementally added to an end of an extensible boom 4. <P>SOLUTION: This tilt angle detector comprises a jib tilt angle detection means and a jib tilt angle computation means 33. As to the detection means, an end of a length measuring cord 25 extracted from a cord reel 23 fitted with a rotary displacement detector 24 attached to a base end boom 4a is locked 32 onto an appropriate position of a sheave body 15 through a guide sheave 28 provided in a position apart by a prescribed length S from a pivotal shaft 14 rockably pivoting a jib body 15a and rotational displacement of the reel 23 concurrent with a positional change of the end 25a of the measuring cord occurring in tilt-driving the extension jib 12 is detected by the detector 24. The computation means 33 computes the tilt angle of the extension jib 12 based on a jib tilt angle detection signal from the detection means. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD The present invention relates to a tilt angle detection device for an extension jib that is used by supplementing an extension of a telescopic boom in a mobile crane or the like.
[0002]
[Prior art]
The extension jib, which is used as a supplement to the tip of the telescopic boom, is widely used for lifting work at a high place where relatively light loads are lifted on the roof of a building or the like. Description will be given of an example of a conventionally used extension jib which can be attached to a vehicle-mounted crane which is mounted at a position behind a driver's cab of a vehicle and is mainly used for a loading operation for loading luggage on a carrier or the like. .
[0003]
In FIG. 3, A is a vehicle-mounted crane. The on-vehicle type crane A is mounted on a vehicle frame at a position behind a driver's cab of a vehicle (not shown), and a base 2 having left and right outrigger devices 1a and 1b, and swiveling on the base 2 A swivel post 3, which is freely mounted, a telescoping boom 4 pivotally supported on the upper part of the swivel post 3 so as to be able to move up and down, and a plurality of distal booms 4b and 4c are telescopically inserted into a base boom 4a; Alternatively, a hook block 7 is hung up and down from the boom tip 4d (the tip of the foremost side boom 4c) by a wire rope 6 fed from a winch device 5 attached to the base end of the telescopic boom 4. are doing. Reference numeral 9 denotes an up / down cylinder that drives the telescopic boom 4 up and down, and reference numeral 10 denotes a telescopic cylinder that drives the telescopic boom 4 to expand and contract. Reference numeral 11 denotes a jib connecting portion which is attached to the boom tip portion 4d and serves as a mounting base for an extension jib described later.
[0004]
Reference numeral 12 denotes an extension jib which is used to supplement an extension of the distal end of the telescopic boom 4 when a relatively light load is lifted at a high place such as a building. The extension jib 12 includes a jib mounting base 13 that can be attached to the jib connecting section 11 attached to the boom tip 4 d using a connecting pin or the like (not shown), and a base pivotally connected to the jib mounting base 13. A jib body 15 rotatably supported by a support shaft 14 and having a distal end jib 15b slidably housed in a base end jib 15a, a jib mounting base 13 and a jib body interposed between appropriate positions of the base end jib 15a. And a tilt cylinder 16 that drives the tilt 15. The distal side jib 15b is configured to be extendable and retractable with respect to the proximal end jib 15a manually or by a jib extension mechanism (not shown). When the extension jib 12 is not in use, the connection between the jib connection portion 11 and the jib mounting base 13 is released, and the extension jib 12 is turned upside down along the side surface of the telescopic boom 4 (shown by a two-dot chain line in FIG. 3). State).
[0005]
The extension jib 12 configured as described above first swings the extension jib 12 from the retracted position to the distal end side of the telescopic boom 4 to connect the jib connecting portion 11 and the jib mounting base 13, and then the boom distal end 4d The jib hook 17 is suspended from the jib tip 15c, and the jib hook 17 is alternately suspended from the jib tip 15c. Then, after adjusting the tip side jib 15b to an arbitrary extension amount, the luggage is hung on the jib hook 17, the tilt cylinder 16 is driven to tilt the jib body 15, and the winch device 5 is driven to tilt the jib hook 17. To a high place to carry out lifting work at a high place.
[0006]
The drive of the tilt cylinder 16 is configured such that, for example, the control oil switched and controlled by the expansion and contraction control valve 18 for controlling the drive of the expansion and contraction cylinder 10 is selectively switched and supplied by the expansion and tilt switch valve 19 to be driven. I have. That is, when the telescopic / tilt switching valve 19 is switched to the telescopic position a, the telescopic cylinder 10 is driven by the control oil from the telescopic control valve 18, and when the telescopic / tilt switching valve 19 is switched to the tilt position b, the tilt cylinder is controlled by the control oil from the telescopic control valve 18. 16 are driven.
[0007]
On the other hand, since this type of extension jib 12 is extended at the tip of the telescopic boom 4, there is a problem that the height of the ground at the time of work is high and it is difficult for the operator to grasp the operating posture such as the dibutyl angle. . For this reason, the tilt angle detecting device 20 that detects the dibutyl tilt angle and displays it visually is attached to the extension jib 12. The conventional tilt angle detecting device 20 includes a tilt angle detector 20a attached to the base end jib 15a and detecting a ground angle of the base end jib 15a with a known ground angle detector and outputting a tilt angle detection signal. A cord winder 20b attached to the end boom 4a and transmitting a tilt angle detection signal detected by the tilt angle detector 20a to the turning post side, and a cord winding device 20b for extending the jib 12 based on the tilt angle detection signal transmitted to the turning post side. And the tilt angle calculating means 24c for calculating the tilt angle. Then, the tilt angle calculated by the tilt angle calculating means is displayed so as to be visible to the operator, or added to operating range restricting means for preventing the crane from moving beyond the allowable operating range. Entered as operation information.
[0008]
[Problems to be solved by the invention]
However, the conventional tilt angle detection device 20 has a problem in that it requires a code winder 20b for transmitting a tilt angle detection signal to the turning post side, in addition to the tilt angle detector 20a, and is expensive. In addition, the cord winder 20b has a built-in rotary joint that is a source of electric noise, and thus has a problem that low-noise signals cannot be transmitted.
[0009]
SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an extended jib tilt angle detection device capable of obtaining a low-cost, low-noise dibutyl angle detection signal.
[0010]
[Means for Solving the Problems]
The present invention has the following configuration as means for solving the above problems.
[0011]
That is, the tilt angle detecting device for a re-extension jib of the present invention is a re-extension jib that can supplementally extend to the distal end portion of a telescopic boom in which a plurality of distal booms are telescopically inserted into a proximal boom. And a jib mounting base detachably attached to the boom tip and a jib body pivotally supported by a pivot shaft on the jib mounting base and tilt-driven by a tilt cylinder. For the tilt angle detection device.
[0012]
The tilt angle detecting device is configured such that the distal end of a length measuring cord pulled out from a cord reel with a rotational displacement detector attached to a base end boom is moved by a predetermined length from a pivot shaft that pivotally supports the jib body. With the guide sheave provided at the separated position passing, the jib body is locked in place and extended, and the rotation displacement of the code reel caused by the position change of the length measuring cord tip generated at the time of tilt driving of the jib is detected by the rotation displacement detector. And a dibutylt angle detection means for outputting a dibutylt angle detection signal, and a dibutylt angle calculation means for calculating the tilt angle of the additional jib based on the dibutylt angle detection signal from the dibutylt angle detection means.
[0013]
In the tilt angle detecting device configured as described above, the tip of the length measuring cord pulled out from the code reel by the dibutyl tilt angle detecting means is provided at a position separated by a predetermined length from a pivot shaft that pivotally supports the jib body. The guide sheave has been passed and the jib body is locked in place. For this reason, if the tilt angle of the extension jib changes by tilting the extension jib and the extension angle of the extension jib changes, the leading end position of the length measuring cord moves in the longitudinal direction of the cord with the change, and the code reel rotates. Is detected by the rotational displacement detector and output as a dibutylt angle detection signal. The detected dibutylt angle detection signal is input to the dibutylt angle calculating means to calculate the tilt angle of the additional jib, which is displayed so as to be visible to the operator, or the operating range as the actual operation information of the additional jib. The information is input to the regulating means and used for various controls.
[0014]
As described above, the tilt angle detecting device of the present invention is configured such that the extension length of the length measuring cord pulled out from the code reel by the tilt drive of the extension jib changes, and this change in the extension length is determined by the rotational displacement. Since the rotation displacement of the code reel is detected by using the detector, the tilt angle of the additional jib can be detected at the position where the code reel is disposed, that is, on the base end boom. The posting portion of the dibutyl tilt angle detecting means can be constituted by simply adding a rotational displacement detector for detecting the rotational displacement of the code reel to the conventional cord winder, and the tilt angle for detecting the ground angle of the extended jib. Since the detector is not required, the cost can be reduced. Further, the detecting section of the dibutylt angle detecting means has the same structure as the boom length detecting means for detecting the boom length of the telescopic boom provided in many of this type of crane. In this case, the dibutylt angle detecting means can be configured at a lower cost only by changing the locking position of the tip of the length measuring cord toward the jib body. Further, since the rotational displacement detector can be mounted on the fixed side of the base end boom, the dibutylt angle detection signal can be directly input to the dibutylt angle calculating means without passing through the rotary joint which is a source of electrical noise. Therefore, it is possible to accurately calculate the tilt angle using a low-noise signal.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described with reference to FIGS. The tilt angle detection device according to the present invention is configured by adding a rotational displacement detector to the cord winder described as the prior art with reference to FIG. 3 and changing the position at which the tip of the length measuring cord is locked. In the following description, this difference will be mainly described. For this reason, the reference numerals 1 to 19 used in the description of the related art are used as synonyms in the following description.
[0016]
In FIG. 1, reference numeral 22 denotes a cord winder attached to a side surface of the base end boom 4a. In the cord winder 22, a rotational displacement detector 24 for detecting the rotational displacement of a cord reel 23 is attached to a conventional cord winder 20b, and a length measuring cord conventionally fixed to a boom tip 4d. 25, the distal end locking position 25a is changed to the jib body 15a side as described later.
[0017]
As shown in FIG. 2, the rotational displacement detector 24 is a rotational displacement of the code reel 23 which urges the length measuring cord 25 to rotate in the cord winding direction by the urging force of the winding spring 26 on the body 23a, that is, the length measuring code. A known detector such as a potentiometer or a rotary encoder that transmits the rotational displacement of the code reel 23 that rotates in conjunction with the pulling out or winding of the cord 25 through a gear transmission mechanism 27 and outputs a detection signal corresponding to the rotational displacement. It is configured. For this reason, if the length of the cord is changed due to the length measuring cord 25 being pulled out or wound up, the cord reel 23 is rotationally displaced by the change in the extended length, and the rotational displacement is detected by the rotational displacement detector 24. And outputs a detection signal. The configuration of the rotational displacement detector 24 is the same as that of a boom length detecting means for detecting the boom length of the telescopic boom 4 which is provided in many cranes of this type in recent years. It is possible to use the length detecting means as a dibutylt angle detecting means.
[0018]
In FIG. 1, reference numeral 28 denotes a guide sheave for guiding the length measuring cord 25. In this embodiment, a guide sheave is provided at a position separated by a predetermined length s from the pivot shaft 14 that pivotally supports the jib body 15 in a swingable manner. A jib mounting base 11 is rotatably supported by a sheave shaft 29 erected at a position near the lower pivot shaft 16a of the dibutyl cylinder. Reference numeral 30 denotes an auxiliary guide sheave which is attached to the boom tip 4d and guides the length measuring cord 25 in an S-shape such that the length measuring cord 25 always extends along the guide sheave 27. Reference numeral 32 denotes a jib-side cord locking member that stands upright at a position near the upper pivot 16b of the dibutylt cylinder 16 and locks and fixes the distal end locking portion 25a of the length measuring cord 25.
[0019]
The length-measuring cord 25 pulled out from the cord reel 23 is sequentially wound around the auxiliary guide sheave 30 and the guide sheave 28, and the leading end 25 a is locked by the jib-side cord lock 32. Therefore, if the tilt angle of the jib body 15 changes by tilting the dibutyl cylinder 16, the length between the guide sheave 28 and the jib-side cord locking member 32, that is, the length of the length of the length measuring cord 25. If L changes ΔL, and the rotational displacement of the code reel 23 that rotates with this is detected by the rotational displacement detector 24, a dibutyl angle detection signal corresponding to the tilt angle of the additional jib 12 can be detected. Then, the detected dibutyl angle detection signal is inputted to the dibutyl angle calculating means 33, the tilt angle is calculated by the calculating means 33, and displayed on the display 34. Further, the tilt angle calculated by the dibutyl tilt angle calculating means 33 is input to an operating range restricting device (not shown) as necessary, and is used for various controls as actual operating information of the additional jib.
[0020]
In this embodiment, the mounting position of the guide sheave 28 is set at a position near the lower pivot shaft 16a of the dibutyl cylinder 16, and the mounting position of the jib-side cord locking member 32 is set at a position near the upper pivot shaft 16b. However, the former mounting position can be mounted at any other position as long as it is a position on the jib mounting base 11 that is separated to some extent from the pivot 14 that pivotally supports the jib main body 15, Also, the latter attachment position can be attached to any other position as long as it is a position on the jib body 15 which is separated from the pivot shaft 14 to some extent.
[0021]
When the extension jib 12 is detached from the distal end 4d of the telescopic boom 4 and stored on the side surface of the telescopic boom 4, the distal end 25a of the length measuring cord 25 is detached from the jib-side cord lock 32. This is a boom-side cord locking tool for temporarily locking to the boom tip side 4d. When the tip 25a of the length measuring cord 25 is locked to the boom-side cord locking member 34, the configuration becomes the same as that of the boom length detecting means. , The boom length of the telescopic boom 4 can be calculated. In the case of such a configuration, when the end of the length-measuring cord 25a is locked to the jib-side cord locking tool 32 corresponding to the change of the locking position, the dibutyl tilt angle is calculated from the dibutyl tilt angle detection signal, It is preferable to provide an operation switching means so as to calculate the boom length from the dibutylt angle detection signal when the boom length is locked by the boom-side cord locking member.
[0022]
Further, the tilt angle detecting device for the extension jib 12 according to the present invention calculates a dibutyl tilt angle by detecting a change in the extension length of the length measuring cord 25 extended between the base end boom 4d and the jib body 15. Therefore, if the telescopic boom 4 is erroneously expanded or contracted during the tilt driving of the extension jib 12, the change in the boom length due to the expansion or contraction driving will cause the amount of change in the extension length of the length measuring cord 25 (dibutylt angle detection). Signal), it is not possible to calculate the exact dibutyl tilt angle. Therefore, during the tilt driving of the extension jib, the hydraulic driving is performed simultaneously using the telescopic / tilt switching valve 19 and the like so that the telescopic boom 4 cannot be telescopically driven. It is better to regulate.
[0023]
The tilt angle detecting device thus configured adds a rotational displacement detector 24 for detecting the rotational displacement of the code reel 23 to the conventional cord winder, and sets the locking position of the length measuring cord tip 25a to the jib body. By simply changing to the 15 side, the structure can be easily configured, and the tilt angle detector for detecting the ground angle of the extension jib 12 can be configured at a low cost because the tilt angle detector is not required. Further, since the rotational displacement detector 24 can be attached to the fixed side of the base end boom 4a, the dibutylt angle detection signal is directly input to the dibutylt angle calculating means without passing through the rotary joint which is a source of electric noise. This makes it possible to calculate an accurate tilt angle using a low-noise signal.
[0024]
【The invention's effect】
The extension jib tilt angle detection device of the present invention configured as described above is configured such that the extension length of the length measuring code is changed by tilting the extension jib, and the change in the extension length is determined by the code. Since the rotation displacement of the reel is detected by the rotation displacement detector, the tilt angle of the extended jib can be detected on the base end boom side, eliminating the need for a tilt angle detector to detect the ground angle of the extended jib In addition to this, it is possible to reduce the cost, and it is not necessary to pass through a rotating joint which is a source of electrical noise, and it is possible to calculate the tilt angle accurately using a low-noise signal.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a tilt angle detection device for a continuous jib according to the present invention.
FIG. 2 is an explanatory diagram of a main part of FIG. 1;
FIG. 3 is an explanatory view of a conventional additional jib tilt angle detecting device.
[Explanation of symbols]
A On-board crane,
1a, 1b outrigger device,
2 bases,
3 turning post,
4 Telescopic boom,
4a proximal boom,
4b, 4c tip boom,
4d boom tip,
5 winch device,
6 wire rope,
7 Hook block,
9 Undulating cylinder,
10 telescopic cylinders,
11 jib connection,
12 Addition jib,
13 Jiff mounting base,
14 pivot axis,
15 jib body,
15a proximal jib,
15b Tip side jib,
16 tilt cylinder,
17 Jib hook,
18 telescopic control valve,
19 Telescopic / tilt switching valve,
20a tilt angle detector,
20b, 22 cord winder,
23 code reels,
23a trunk,
24 rotational displacement detector,
25 Measurement code,
25a tip,
26 spring,
27 gear transmission mechanism,
28 Guide sheave,
29, 31 sheave axis,
30 auxiliary guide sheave,
32 jib side cord lock,
32 jib side cord lock,
33 dibutylt angle calculating means,
34 frame side cord locking device,

Claims (1)

A jib mounting base that is releasably attached to the distal end of the boom, which is a resilient jib that can be supplementarily extended to a distal end of the telescopic boom in which a plurality of distal booms are telescopically inserted into the base boom. A tilt angle detection device for a refill jib, comprising a base and a jib body pivotally supported by a pivot shaft on the jib mounting base and tilt-driven by a tilt cylinder,
A guide provided at a position separated by a predetermined length from a pivot shaft for pivotally supporting the jib body so that the distal end of the length-measuring cord pulled out from a cord reel with a rotational displacement detector attached to the base end boom is provided. After the sheave has passed, the jib body is locked in place and added, and the rotation displacement of the code reel due to the change in the position of the tip of the length measuring cord that occurs at the time of tilt driving of the jib is detected by the rotation displacement detector as a dibutylt angle detection signal. A tilt angle of the extended jib, wherein the tilt angle of the extended jib is constituted by: a dibutyl tilt angle detecting means for outputting; and a dibutyl tilt angle calculating means for calculating a tilt angle of the additional jib based on the dibutyl angle detection signal from the dibutyl tilt angle detecting means. Detection device.

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