JPH11106182A - Expansion/contraction position detection device for outrigger cylinder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a necessity to prevent the rotation of an outrigger cylinder by expanding/contracting a rod, to reduce the strength of a detection rod a guide member, and to reduce the weight of an outrigger device. SOLUTION: In an outrigger device provided with an outrigger cylinder 1, its cover 5, and a ground-contact member 4 at a lower end of a rod 2 of the outrigger 1, a spacer 6 is housed over the rod 2 at a lower part of the rod in a turnable manner, a detection rod 9 is erected on the spacer 6, a guide member 10 to guide the vertical movement of the detection rod 9 is provided on a cylinder tube 3, position detection bodies 12, 13 to detect the expansion position and the contraction position of the outrigger cylinder 1 are provided on the detection rod 9, and position detectors 14, 15 are provided at the position corresponding to the position detectors 12, 13 on the cover 5 when the outrigger cylinder 1 is in the expansion position and in the contraction position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outrigger device, such as a crane mounted on a vehicle, for detecting the extension / retraction position of an outrigger cylinder for detecting the extension position and contraction position of an outrigger cylinder for extending / retracting the outrigger device. It concerns the device.

[0002]

2. Description of the Related Art In a conventional outrigger device, an outrigger cylinder is used as a telescopic means. As shown in FIG. 3, in the outrigger device, the outrigger cylinder 1
Is connected to a body such as a crane (not shown) with the rod 2 side down, a grounding member 4 is connected to the lower end of the rod 2 that expands and contracts with respect to the cylinder tube 3, and the rod 2 is extended to ground. By grounding the member 4 on the ground, stability of the body such as a crane at the time of work is achieved. Also, rod 2
The outrigger device is brought into the retracted state by reducing the height of the grounding member 4 to reduce the size of the grounding member 4. A cover 5 is provided outside the outrigger cylinder 1.

Conventionally, in the outrigger cylinder 1 of the outrigger device configured as described above, the extended position and the contracted position of the outrigger cylinder 1 are detected by setting a required length detection rod 9 on the grounding member 4 and lowering the rod 2 by expansion and contraction of the rod 2. Alternatively, the detection is performed by detecting the position of the detection rod 9 that moves upward.

In the outrigger device shown in FIG. 3, a position detector 12 for detecting the extended position of the outrigger cylinder 1 and a position detector for detecting the contracted position are located at appropriate positions on the detection rod 9 erected on the grounding member 4. A position detector 1 for detecting the extended position of the outrigger cylinder 1 at a position facing the position detecting body 12 when the outrigger cylinder 1 is at the extended position.
4, and when the outrigger cylinder 1 is located at a position facing the position detector 13 when the outrigger cylinder 1 is at the contracted position.
Is provided with a position detector 15 for detecting the reduced position. Proximity switches are used for the position detectors 14 and 15. Limit switches or the like may be used as the position detectors 14 and 15.

When the rod 2 extends, the detection rod 9 moves downward, and when the outrigger cylinder 1 reaches the extension position, the position detector 12 approaches the position detector 14, so that the outrigger cylinder 1 is in the extension position. Is the position detector 14
Is detected by

When the rod 2 contracts, the detection rod 9 moves upward, and when the outrigger cylinder 1 reaches the contraction position, the position detector 13 approaches the position detector 15, so that the outrigger cylinder 1 is in the contraction position. Is the position detector 15
Is detected by

When the outrigger cylinder 1 expands and contracts, the rod 2 rotates with respect to the cylinder tube 3. When the rod 2 rotates with respect to the cylinder tube 3, the detection rod 9 is displaced from the position where the position detectors 14 and 15 are mounted, so that the extension position and the contraction position of the outrigger cylinder 1 may not be detected.

Therefore, the guide member 1 is attached to the cylinder tube 3.
0 is provided to guide the vertical movement of the detection rod 9 and prevent the rod 2 from rotating.

[0009]

However, since the rotational force of the rod 2 generated by the expansion and contraction of the outrigger cylinder 1 is extremely large, the diameter of the detection rod 9 must be large in order to prevent the rotation of the rod 2 due to expansion and contraction. Therefore, it is necessary to increase the strength of the guide member 10. Therefore, there is a problem that the size of the outrigger device increases, the weight increases, and the cost increases.

The present invention solves such a problem in the outrigger device, and it is not necessary to prevent rotation of the outrigger cylinder due to expansion and contraction of the rod, so that the diameter of the detection rod can be reduced and the strength of the guide member can be reduced. It is another object of the present invention to provide an outrigger cylinder expansion / contraction position detecting device capable of reducing the weight and cost of the outrigger device.

[0011]

According to the outrigger cylinder expansion / contraction position detecting device of the present invention, an outrigger cylinder that expands / contracts, a cover that covers the outside of the outrigger cylinder, and a ground member connected to a lower end of a rod of the outrigger cylinder are provided. In the outrigger device provided with a guide, the spacer is rotatably fitted to the lower part of the rod of the outrigger cylinder so as to be rotatable with respect to the rod, the detection rod is erected on the spacer, and the vertical movement of the detection rod is guided to the cylinder tube of the outrigger cylinder. A member is provided, and a detection rod is provided with a position detector for detecting the extension position and the contraction position of the outrigger cylinder, and the cover is located at a position corresponding to the position detector when the outrigger cylinder is at the extension position and the contraction position. The above problem is solved by providing a detector.

When the outrigger cylinder extends or contracts, the spacer moves downward or upward together with the rod, and accordingly, the detection rod moves downward or upward. When the outrigger cylinder reaches the extension position or the contraction position, the position detecting body reaches a position corresponding to the position detector, and the position detector detects that the outrigger cylinder is in the extension position or the contraction position.

When the outrigger cylinder expands and contracts, the rod rotates with respect to the cylinder tube. At this time, the spacer tends to rotate together with the rod due to frictional force.
However, the rotation of the spacer does not occur because the detection rod is restrained by the guide member. Since the spacer is rotatably fitted to the rod and the frictional force between the spacer and the rod is extremely small, the force acting on the detection rod and the guide member is also small, and the detection rod and the guide member have low strength. No problem. Therefore, the weight of the outrigger device can be reduced and the cost can be reduced.

[0014]

FIG. 1 is a longitudinal sectional view showing a contracted state of an outrigger device provided with an outrigger cylinder extension position detecting device according to an embodiment of the present invention, and FIG. FIG.

Here, the basic structure of the outrigger device is the same as that of the conventional outrigger device, and the outrigger cylinder 1 is connected to a body such as a crane (not shown) with the rod 2 side down. A grounding member 4 is connected to the lower end of the rod 2 that expands and contracts with respect to the cylinder tube 3. Measure. Further, the outrigger device is set in the retracted state by reducing the rod 2 and raising the grounding member 4. A cover 5 is provided outside the outrigger cylinder 1.

At the lower end of the rod 2 of the outrigger cylinder 1, a spacer 6 having a through hole having an inner diameter slightly larger than the outer diameter of the rod 2 is rotatably fitted to the rod 2. A detection rod 9 of a required length is provided upright on the spacer 6. Since the upper and lower portions of the spacer 6 are restrained by the flanges 7 and 8 and move downward or upward as the rod 2 expands and contracts, the detection rod 9 also moves downward or upward at the same time.

The cylinder tube 3 of the outrigger cylinder 1 is provided with a guide member 10 for guiding the detection rod 9 up and down. The cylinder tube 3 is provided with a plate 11 for preventing the cover 5 from swinging.
The distance between the detection rod 9 and the cover 5 is kept constant.

At the upper end of the detection rod 9, a position detector 12 for detecting the extension position of the outrigger cylinder 1 is provided. A position detector 13 for detecting the reduced position of the outrigger cylinder 1 is formed in a portion of the spacer 6 where the detection rod 9 is provided upright.

The cover 5 has a position detector 14 for detecting the extended position at a position corresponding to the position detector 12 when the outrigger cylinder 1 is at the extended position, and a position detector when the outrigger cylinder 1 is at the contracted position. Position detectors 15 for detecting the reduced position are provided at positions corresponding to the positions 13. Here, proximity switches are used as the position detectors 14 and 15. The position detectors 14, 15
For example, a limit switch or the like may be used.

When the rod 2 extends, the detection rod 9 moves downward together with the spacer 6. When the outrigger cylinder 1 reaches the extended position, the position detector 12 approaches the position detector 14, so that the position detector 14 detects that the outrigger cylinder 1 is in the extended position.

When the rod 2 contracts, the detection rod 9 moves upward together with the spacer 6. When the outrigger cylinder 1 reaches the contracted position, the position detector 13 approaches the position detector 15, so that the position detector 15 detects that the outrigger cylinder 1 is at the contracted position.

When the outrigger cylinder 1 expands and contracts, the rod 2 rotates with respect to the cylinder tube 3. At this time, the spacer 6 tries to rotate together with the rod 2 due to frictional force. However, since the detection rod 9 is guided by the guide member 10, the spacer 6 does not rotate.
Since the spacer 6 is rotatably fitted to the rod 2 and the frictional force between the spacer 6 and the rod 2 is extremely small, the force acting on the detection rod 9 and the guide member 10 is also very small. The guide member 10 may have a small strength. Therefore, according to the outrigger cylinder position detecting device, the weight of the outrigger device can be reduced and the cost can be reduced.

In the above outrigger cylinder position detecting device, two position detectors and two position detectors are provided. By appropriately selecting the installation positions, two position detectors are provided. It is also possible to provide one position detector, or provide one position detector and two position detectors.

[0024]

As described above, the outrigger cylinder position detecting device of the present invention does not need to prevent rotation due to the expansion and contraction of the rod, and can reduce the diameter of the detection rod and reduce the strength of the guide member. The outrigger device can be reduced in weight and cost.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a contracted state of an outrigger device including an outrigger cylinder extension position detecting device according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing an extended state of the outrigger device.

FIG. 3 is a longitudinal sectional view showing a contracted state of an outrigger device provided with a conventional outrigger cylinder extension position detecting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outrigger cylinder 2 Rod 3 Cylinder tube 4 Installation member 5 Cover 6 Spacer 7 Flange 8 Flange 9 Detection rod 10 Guide member 11 Plate 12 Position detector 13 Position detector 14 Position detector 15 Position detector

Claims (1)

[Claims] 1. An outrigger device comprising: a retractable outrigger cylinder; a cover for covering the outside of the outrigger cylinder; and a ground member connected to a lower end of a rod of the outrigger cylinder. The detection rod is installed upright on the spacer, and a guide member for guiding the vertical movement of the detection rod is provided on the cylinder tube of the outrigger cylinder. Detecting the expansion and contraction position of the outrigger cylinder, wherein a position detector is provided at a position corresponding to the position detector when the outrigger cylinder is at the extended position and the contracted position, and apparatus.