JP2001330007A - Multi-stage cylinder device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce bending load applied to a piston rod. SOLUTION: A telescopic guide 17 of which three stages of guide cylinders 17a, 17b, and 17c slide with a telescopic motion of each of two cylinders 15 and 16 connected in two stages is disposed outside the cylinders 15 and 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-stage cylinder device in which a plurality of cylinders having their respective central axes shifted are connected in multiple stages.

[0002]

2. Description of the Related Art In order to shorten the total contraction length of a cylinder as much as possible and make the stroke as long as possible, a multi-stage telescopic cylinder or a plurality of cylinders having their respective center axes shifted are arranged. 2. Description of the Related Art A multistage cylinder device connected in multiple stages is known.

[0003]

However, in the telescopic cylinder, the pressure receiving area of the piston in each stage changes as the number of stages increases, so that the vertical speed and thrust change. Further, in the multi-stage cylinder device, although the vertical speed and the thrust are constant, since the center of each cylinder is shifted, a couple is generated in addition to the thrust of the piston, which is adversely affected by the bending load on the piston rod.

Accordingly, an object of the present invention is to provide a multi-stage cylinder device in which a bending load acting on a piston rod is reduced.

[0005]

In order to achieve the above object, the present invention provides a multi-stage cylinder device in which a plurality of cylinders are connected in a multi-stage manner.
It is characterized in that a telescopic type guide having one more guide cylinder than the number of cylinders that slides as the cylinders expand and contract is provided.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a working device elevating cylinder device of a steel pipe sheet pile construction machine, which is a kind of a pile driving machine, will be described below with reference to FIGS. A steel pipe sheet pile construction machine 4 in which a working device 3 is provided on a leader 2 erected in front of a base machine 1 so as to be able to ascend and descend is mounted on a top bracket 5 provided on the top of the leader 2 and a back stay 6 provided on a rear portion of the base machine 1. , 6 are connected to support the reader 2.

The working device 3 is provided on a frame 8 supported by a pair of left and right lifting cylinder devices 7, 7 provided on the top bracket 5, and the frame 8 is provided with guide gibs 9, 9.
Engages with the guide pipe 10 of the reader 2 and moves up and down along the leader 2 by expansion and contraction of the lifting cylinder devices 7 and 7.

The working device 3 has a steel pipe press-fitting device 11 and an auger motor 12. The steel pipe press-fitting device 11 is provided with press-fit cylinders 13, 13 provided on a frame 8 and a guide post 1.
The steel pipes supported by the press-fitting cylinders 13 and 13 and connected to the lower part of the steel pipe press-fitting device 11 by the extension of the press-fitting cylinders 13 and 13 are pressed into the ground, and the auger motor 12 rotates an auger screw for excavating the inside of the steel pipes.

The lifting / lowering cylinder device 7 is provided with a cylindrical guide 17 outside two cylinders 15 and 16 whose central axes are shifted from each other. The guide 17 includes a lower guide cylinder 17a and a lower guide cylinder 17a. A middle guide cylinder 17b slidably provided in the cylinder 17a;
Upper guide cylinder 17c slidably provided in 7b
It is composed of The cylinder 15 has the tip of the piston rod 15a connected to the bottom of the lower guide cylinder 17a, the lower end of the cylinder body 15b fixed to the bottom of the middle guide cylinder 17b, and the cylinder 16 has the tip of the piston rod 16a connected to the middle guide cylinder 17a. The upper end of the cylinder body 16b is connected to the ceiling of the upper guide cylinder 17c.

[0010] Hydraulic piping for operating the two cylinders 15, 16 is formed on a piston rod 15a and a piston rod 16a. That is, the piston rod 15a has a pipe 15c to the extension side chamber of the cylinder body 15b and a pipe 15d to the contraction side chamber, and the piston rod 16a has a pipe 16c to the extension side chamber of the cylinder body 16b and a pipe to the contraction side chamber. Each of the paths 16d is formed.

The piston rod 15 of the pipes 15c and 15d
Pipes 18 and 19 from a hydraulic drive source are connected to the lower end of the cylinder body 15b, respectively.
The pipe 21 is connected to the pipe 16d by a pipe 21.

With this configuration, when pressure oil is supplied to the pipeline 15c of the piston rod 15a, the middle guide tube 17b rises from the lower guide tube 17a due to the extension of the piston rod 15a, and the piston rod 16a extends due to the extension of the piston rod 15a. The upper guide cylinder 17c rises from the middle guide cylinder 17b. The maximum extension length of the guide 17 is approximately equal to the sum of the lengths when the piston rod 15a and the piston rod 16a are extended to the maximum. When pressure oil is supplied to the pipe 15d, the middle guide cylinder 17b is lowered into the lower guide cylinder 17a by the reduction of the piston rod 15a, and the upper guide cylinder 17c is lowered into the middle guide cylinder 17b by the reduction of the piston rod 16a. I do. Since the minimum contraction length of the guide 17 is approximately equal to the minimum contraction length of one cylinder, the minimum contraction length is about half as compared with a single cylinder having the same stroke. The piston rod 15
a and 16a so that the directions of expansion and contraction are reversed.
5 and 16 may be provided side by side.

When the cylinders 15 and 16 are operated, a couple occurs because the center axes of the cylinders 15 and 16 are displaced from each other.
The piston rod 15a
In addition, the bending load acting on the piston rod 16a decreases.

FIG. 6 shows a third embodiment of the present invention composed of three cylinders 30, 31, 32 arranged with their respective central axes shifted and a guide 33 having four stages of guide cylinders 33a, 33b, 33c, 33d. 2 shows an example of the embodiment, and
The tip of the piston rod 30a of the step cylinder 30 is connected to the bottom of the first step guide cylinder 33a, the lower end of the cylinder body 30b is fixed to the bottom of the second step guide cylinder 33b, and the tip of the piston rod 31a of the second cylinder 31 is Two-stage guide cylinder 3
3b, and connect the upper end of the cylinder body 31b to the third
One fixed to the bottom of the step guide cylinder 33c, the tip of the piston rod 32a of the third cylinder 32 is connected to the bottom of the third step guide cylinder 33b, and the upper end of the cylinder body 32b is connected to the ceiling of the fourth step guide cylinder 33d. It is. Note that the same configuration can be applied to four or more cylinders whose center axes are shifted from each other. In the illustrated embodiment, three cylinders 30, 31, and 32 are described side by side for convenience.
By disposing the guides 32 in the guide 33 with a phase shift of 120 degrees, the guide 33 can be configured without increasing the cylinder diameter of the guide 33. When four cylinders are used, the phase can be shifted by 90 degrees to increase the guide cylinder diameter. It can be configured without doing.

[0015]

As described above, the multi-stage cylinder device of the present invention slides along the expansion and contraction of each cylinder outside the plurality of cylinders arranged in a multi-stage arrangement with their respective center axes shifted. The guide cylinder is one more than the number of cylinders
Since a telescopic guide with many steps is provided,
During operation of the cylinder, each stage guide cylinder of the guide bears a couple generated due to the misalignment of the center axis of the cylinder, so that the bending load acting on the piston rod of each cylinder decreases. Further, the minimum reduction length can be shortened by increasing the number of guide steps by one step as compared with a plurality of cylinders arranged with their respective center axes shifted.

[Brief description of the drawings]

FIG. 1 is a sectional view of a lifting cylinder device.

Fig. 2 Side view of steel pipe sheet pile construction machine

FIG. 3 is a plan view of a steel pipe sheet pile construction machine.

FIG. 4 is a front view of the working device.

FIG. 5 is a partially cutaway plan view of the lifting cylinder device.

FIG. 6 is a sectional view of a cylinder device according to a second embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Base machine, 2 ... Leader, 3 ... Working device, 4 ... Steel pipe sheet pile construction machine, 7 ... Lifting cylinder device, 15, 16 ... Cylinder, 15a, 16a ... Piston rod, 15b, 1
6b: cylinder body, 17: guide cylinder, 17a: lower guide cylinder, 17b: middle guide cylinder, 17c: upper guide cylinder

Claims (1)

[Claims] 1. A multi-stage cylinder device in which a plurality of cylinders are connected in a multi-stage manner. A multi-stage cylinder device provided with a guide.