JPH036665Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention, as shown in Figs. 6 and 7, is a device for lifting and lowering pillars 2 vertically installed at each corner of a pontoon 1 at a desired work execution position on the sea. 31, and the pontoon 1 is raised above the sea against the rear pillar 2, which is fixed against waves, tides, wind forces, etc., and underwater piling, underwater boring, submergence sinking, etc. This invention relates to a cylinder-type lifting device for structures such as self-lifting work platforms used for offshore work.

BACKGROUND ART Conventionally, as a cylinder-type lifting device, for example, a lifting device (Japanese Patent Publication No. 36768/1983) has been known.
As shown in FIGS. 8 and 9, this conventional device includes a holding frame 32 fixed to the upper surface of a pontoon 1 and surrounding a pillar 2, and a pair of lifting cylinders 33, 33 connected to the holding frame 32. It consists of a working frame 34 that is fitted into the pedestal 2 through appropriate guides, and the frames 34 and 32 have a pair of rectangular toothed racks 35 and 35 vertically installed at the front and back of the pedestal 2, respectively. The locking piece locking and disengaging devices 38 and 39 are provided to lock and release the locking pieces 36, 36, 37, and 37, and the locking pieces 36, 36 of the working frame 34 can be locked by the locking pieces 35, 36 when the pedestal 2 or the pontoon 1 is raised and lowered. 35, and with the locking pieces 37, 37 of the holding frame 32 disengaged from the racks 35, 35, the lifting cylinders 33, 33 are operated, and one of the racks 35 is engaged.
When the vertical movement of the pitch pillar 2 or pontoon 1 is completed, the locking pieces 37, 37 of the holding frame 32 are engaged with the racks 35, 35, and the locking pieces 36, 36 of the working frame 34 are engaged with the racks 35, 35. 35, the load is transferred from the working frame 34 to the holding frame 32, and here the lifting cylinders 33, 33 are operated in the opposite direction to the front by one pitch of the rack 35, and then the working frame 34 is locked. piece 36,
36 is engaged with the racks 35, 35, and the locking pieces 37, 37 of the holding frame 32 are engaged with the racks 35, 35.
5 and 35 and transfer the load from the holding frame 32 to the working frame 34, the raising and lowering operation of the rack 35 for one pitch is completed. 1 is intermittently raised or lowered.

By the way, the lifting device has a pillar 2 having a rectangular cross section.
Therefore, when working in sea areas with severe sea conditions such as wave height and tidal current, the drag coefficient of pedestal 2
Since C _D is large, the lateral external force F acting on the pillar 2 in FIG. 10 becomes very large. Lateral external force F
Accordingly, the reaction force from the seabed support part of the pedestal 2, that is, the horizontal reaction force f=F/2 and the longitudinal reaction force R=F·H ₁ /L also increases. Then, due to the lateral reaction force f, a bending moment of M=f・H ₂ =F/2H ₂ acts on the pillar 2 at the bottom of the pontoon 1, and as the lateral external force F increases, the bending moment also increases. Therefore, it was necessary to increase the strength of the members of the pillar 2. In addition, the lifting device 31
The longitudinal reaction force R is transmitted through the pedestal 2, and this longitudinal reaction force R increases as the lateral external force F increases, so there are problems such as the need to increase the strength and capacity of the lifting device 31 accordingly.

Therefore, an elevating device (US Pat. No. 3,401,917) has been proposed that targets a pedestal 2 having a circular cross section in which the drag coefficient C _D of the pedestal 2 is smaller than that of a pedestal 2 having a rectangular cross section.

As shown in FIG. 11, this conventional device has an annular shape that is fitted into a pillar 2 having a circular cross section between the upper part of a pontoon 1 and a lifting device support frame (not shown) and connected by a lifting cylinder 41. An upper frame 42 and a lower frame 43 are arranged, and each of the frames 42 and 43 has pin holes 44 provided at regular intervals in the longitudinal direction of the pillar 2, and pins 45 and 46 that fit in and out. A locking and disengaging device is installed internally, and the pin hole 44 is inserted into the tooth groove of the rack 35 of the conventional device shown in FIGS. They respectively correspond to hydraulic cylinders 33, and intermittently raise or lower the pedestal 2 or pontoon 1 by operations similar to those of the conventional device shown in FIGS. 3 and 4.

Problems to be Solved by the Invention However, as shown in Fig. 11, this conventional device has a structure that supports the load by cantilever support of the pins 45 and 46, so the capacity of the lifting device has increased and accordingly. As the outer diameter of the lifting cylinder 41 increases, the amount of eccentricity between the pin support point of the pin hole 44 and the central axis of the lifting cylinder 41 increases, and a large bending moment acts on the frames 42, 43. 43 will be enlarged due to reinforcement. Furthermore, as the cross-sectional dimension of the pedestal 2 increases, the frames 42 and 43 also become larger, but since the bending moment acts on the entire frame, the frames 42 and 43 have the disadvantage of becoming even larger.

Means for Solving the Problems The present invention will be explained using FIGS. 1 to 3, which correspond to embodiments.

Racks 5 are installed vertically at the front and rear of the pedestal 2 that penetrates the pontoon 1, and the pedestal 2 is mounted on the pontoon 1.
A locking piece 1 that is fitted into and engages with and disengages from the rack 5.
0a, 10b and engaging/disengaging cylinders 15a, 15b
In an elevating device in which upper and lower frames 6 and 7 are arranged and connected by an elevating cylinder 19, the pillar 2 has a circular cross section, and the upper and lower frames 6 and 7 each have a Main vertical member 16 provided with bearings 12a, 12b on both outside sides of rack 5 for supporting and guiding locking pieces 10a, 10b.
a, 16b are installed vertically, and the center of the lifting cylinder 19 is placed on the central axis 22 of the locking pieces 10a, 10b engaged with the rack 5 on the opposing main vertical members 16a, 16b of both the upper and lower frames 6, 7. Lifting cylinders 19 are connected so that their axes pass through each other.

Operation When the pedestal 2 is supported by the pontoon 1, the load transmission path includes the locking piece 10b of the lower frame 7 shown in FIG. 4a, the bearing part 12b of the lower frame 7, the main vertical member 16b, and the The locking piece 10a of the upper frame 6 shown in C, the bearing part 12a of the upper frame 6,
These are the main vertical member 16a, the lifting cylinder 19, and the main vertical member 16b of the lower frame 7, and when the pontoon 1 is supported on the seabed ground, the load transmission path is the fifth
Lifting device support frame 3, main vertical member 16a of upper frame 6, bearing portion 12a, and locking piece 1 shown in Figure a
0a, rack 5, pillar 2, lifting device support frame 3 shown in FIG. 5C, main vertical member 16a of upper frame 6, lifting cylinder 19, main vertical member 16b of lower frame 7, bearing part 12b, stopper 10b,
The main longitudinal member 16 of the upper frame 6 is the rack 5, the pedestal 2 and in each case a vertical alignment.
a, the load of the pontoon 1 and the pedestal 2 is transmitted through part or all of the bearing part 12a, the locking piece 10a, the lifting cylinder 19, the main vertical member 16b of the lower frame 7, the bearing part 12b, and the locking piece 10b. Communicating.
Therefore, the loads of the pontoon 1 and the pillar 2 are smoothly transmitted through the vertical load transmission path, and the main vertical members 16a of both the upper and lower frames 6, 7
16b, bearing parts 12a, 12b, locking piece 10a,
The loads of the pontoon 1 and the pedestal 2 do not act on structural members other than 10b. Further, main vertical members 16a, 1 are attached to bearings 12a, 12b that support and guide both ends of locking pieces 10a, 10b that engage with a pair of racks 5.
The lifting cylinder 19, which is connected via the lever 6b, has a locking piece 10a whose central axis is engaged with the rack 5.
10b, the main vertical member 16 of both the upper and lower frames 6, 7
a, 16b, bearing parts 12a, 12b, locking piece 10
Since no bending moment acts on the structural members other than a and 10b when the pontoon 1 and the pedestal 2 move up and down, weight reduction can be achieved. Therefore, since the pedestal 2 has a circular cross section, the drag coefficient C _D of the pedestal is smaller than that of a pedestal having a rectangular cross section.

Embodiment An embodiment of the present invention will be explained based on the drawings. 1st
In Figures 1 to 3, 1 is the pontoon, 2 is a pillar guide (not shown) that penetrates the corner of the pontoon 1 and is provided at the lower end of the pontoon 1, and a pillar guide (not shown) that is installed on the top of the pontoon 1. The pedestal is guided in the vertical direction by a pedestal guide 4 provided on the top 8 of the lifting device support frame 3, and a pair of rectangular toothed racks 5 are vertically provided at the front and rear of each pedestal.

The upper frame 6 and the lower frame 7 are attached to the pedestal 2 portion between the top 8 of the lifting device support frame 3 of the pontoon 1 from four sides via support rollers 9, so that they can be raised and lowered relative to the pedestal 2. It is arranged.

These frames 6 and 7 have locking pieces 10a and 10b that engage and disengage from the pair of racks 5 of the pedestal 2, and both ends of the locking pieces 10a and 10b are supported and guided so as to be slidable in the front and rear directions. The locking piece 10 is provided with bearing parts 12a, 12b, and holding fittings 14a, 14b protruding from both ends of the locking pieces 10a, 10b along the outer surfaces 13a, 13b of the bearing parts 12a, 12b.
a, 10b are prevented from coming off from the bearing part 12, and the locking pieces 10a, 10 are connected at one end to the locking pieces 10a, 10b and at the other end to the frames 6, 7.
A cylinder 15 for engaging and disengaging b from the rack 5
a, 15b are arranged.

Therefore, the frames 6 and 7 have a bearing section 1 in the middle.
The main longitudinal members 16a and 16b provided with the main longitudinal members 2a and 12b are arranged parallel to the arrangement direction of the rack 5, that is, in the longitudinal direction, and serve as the main ribs of the frame. and the main longitudinal member 16 in the lower frame 7.
An eye plate 18 is integrally provided on the upper extension of b, and the center axis 22 of the locking pieces 10a, 10b engaged with the rack 5 is aligned with the center axis of the lifting cylinder 19 on the opposing eye plates 17, 18. The lifting cylinders 19 are attached with pins 20 and 21 so as to be perpendicular to each other.

23 is provided on the pins 20 and 21 to prevent bending force from being applied to the lifting cylinder 19, and the eye plate 1
7 and 18, 24 is the main vertical member 1
Joint members welded to the upper and lower parts of 6a and 16b, 25 is an outer wall connecting both the upper and lower joint members 24, and 26 is the pontoon 1 directly below the main vertical member 16b.
The rubber cushion 27 provided above is a load equalization cylinder provided on the upper joint member 24 directly above the main vertical member 16a, and the oil chambers of each load equalization cylinder are communicated with each other through a pipe.

Therefore, the rubber cushion 26, the main longitudinal member 16
b, bearing part 12b, eye plate 18, pin 2
1. The lifting cylinder 19, the pin 20, the eye plate 17, the main vertical member 16a, the bearing part 12a, and the load equalization cylinder 27 are on a common vertical line.

Next, the operation of this embodiment will be explained.

FIG. 4 is an explanatory diagram of the operation when the pillar 2 is raised. In figure a, the pontoon 1 is floating above the sea surface, the lifting cylinder 19 is shortened and the upper frame 6
The locking piece 10a of the lower frame 7 and the locking piece 10 of the lower frame 7
b are both inserted into the rack 5 of the pillar 2,
The upper surface of the locking piece 10b is in contact with the rack 5, and the weight of the pillar 2 is supported by the pontoon 1 via the rack 5, the locking piece 10b, the lower frame 7, and the rubber cushion 26. The lifting cylinder 19 is extended from the state shown in figure a, and the locking piece 10a is moved as shown in figure b.
1 from the locking pieces 10b by touching the top surface of the rack 5 with the rack 5.
Transfer the load to 0a and loosen the locking piece 10b 5
When removed from the cylinder, the lifting cylinder 19 continues.
Extend the pedestal 2 and attach it to the rack 5 as shown in Figure c.
Insert the locking piece 10b into the rack 5 when it is raised by the pitch. Here, when the lifting cylinder 19 is shortened and the upper surface of the locking piece 10b is brought into contact with the rack 5 as shown in FIG. Then, the lifting cylinder 19 is shortened until the rack 5 is shortened by one pitch, and then the locking piece 10a is inserted into the rack 5. This state is the state shown in Figure a. Thereafter, the above-described operations are repeated to raise the pillar 2 to a predetermined height.

The pedestal 2 can be lowered by the same procedure as described above in the reverse cycle of FIGS. 4a-d.

FIG. 5 is an explanatory diagram of the operation when the pontoon 1 is raised. In FIG.
The locking pieces 10b are both inserted into the rack 5, but the lower surface of the locking piece 10a is in contact with the rack 5, and the weight of the pontoon 1 is transferred to the lifting device support frame 3, the load equalization cylinder 27, and the upper frame 6. ,
It is supported on the seabed ground via a locking piece 10a, a rack 5, and a pedestal 2.

The load equalization cylinders 27 are arranged so that even if there is a manufacturing error in the vertical direction between the racks 5 provided at the front and rear of the pedestal 2, the load is evenly applied to each locking piece 10a. 27 oil chambers are communicated with each other.

Now, from the state shown in Fig. 5a, lift cylinder 19
When the lower surface of the locking piece 10b is easily brought into contact with the lower surface of the locking piece 10b as shown in FIG. When the pontoon 1 is extended and raised by one pitch of the rack 5 as shown in Figure c, the locking piece 10a is inserted into the next rack 5. Here, when the lifting cylinder 19 is shortened and the lower surface of the locking piece 10a is brought into contact with the rack 5 as shown in FIG. Then, when the lifting cylinder 19 is shortened and the rack 5 is shortened by one pitch, the locking piece 10b is inserted into the rack 5, resulting in the state shown in Figure a. Thereafter, the above-described operations are repeated to raise the pontoon 1 to a predetermined height.

The lowering of the pontoon 1 can be done by the same procedure as described above in the reverse cycle of FIGS. 5a-d.

In this embodiment, when the pillar 2 is supported by the pontoon 1, the load transmission path includes the locking piece 10b of the lower frame 7, the bearing part 12b,
The main vertical member 16b, the rubber cushion 26, the pontoon 1, the locking piece 10a of the upper frame 6 shown in FIG. , the eye plate 18, the main vertical member 16a of the lower frame 7, the rubber bushing 26, and the pontoon 1. When the pontoon 1 is supported on the seabed ground, the load transmission path is as shown in FIG. The equalizing cylinder 27, the main vertical member 16a of the upper frame 6, the bearing part 12a, the locking piece 10a, the rack 5, the pedestal 2, the lifting device support frame 3 shown in FIG. 5c, and the load equalizing cylinder 2.
7. Main vertical member 16a of upper frame 6, eye plate 17, pin 20, lifting cylinder 19, pin 21, eye plate 18 of lower frame 7, main vertical member 16b, bearing part 12b, locking piece 10b, rack 5 , the pedestal 2, which is the cylinder 27 for load equalization arranged on a vertical line in any case, the main vertical member 16a of the upper frame 6, the bearing part 12a, the locking piece 10a, the eye plate 17, the pin 20, and the lifting/lowering Pontoon 1 through part or all of the cylinder 19, pin 21, eye plate 18, main vertical member 16b of the lower frame 7, bearing part 12b, and locking piece 10b.
It is configured to transmit the load of the pillar 2. Therefore, the loads of the pontoon 1 and the pillars 2 are transmitted smoothly through the load transmission path on the vertical line, and the main vertical members 16a, 1 of both the upper and lower frames 6, 7
6b, bearing parts 12a, 12b, locking pieces 10a, 1
The loads of the pontoon 1 and the pedestal 2 do not act on members other than 0b (hereinafter referred to as other constituent members of both the upper and lower frames 6 and 7). Further, both ends of the locking pieces 10a, 10b that are connected to the pair of racks 5 are connected to bearings 12a, 12b that support and guide them via main vertical members 16a, 16b, eye plates 17, 18, and pins 20, 21. Since the lifting cylinder 19 is arranged so that its center axis passes through the center axis 22 of the locking pieces 10a, 10b engaged with the rack 5, other members of the upper and lower frames 6, 7 are provided with pontoons. No bending moment is applied when the pillars 1 and 2 are moved up and down. However, since the pillar 2 has a circular cross section,
The drag coefficient C _D of the pillar is smaller than that of a pillar with a rectangular cross section.

Effects of the invention As explained above, according to the invention, the load on the pontoon and pedestal is transmitted through the vertical load transmission path consisting of the lifting cylinder and the main vertical members including the bearings of both the upper and lower frames. Therefore, the load can be transmitted smoothly, and the loads of the pontoons and pillars do not act on other structural members of both the upper and lower frames. In addition, since the lifting cylinder is arranged so that the central axis of the locking piece that engages with the rack passes through the center axis of the lifting cylinder, other structural members of both the upper and lower frames include the pontoon and the pedestal. No bending moment is applied when moving up and down. Therefore, it is possible to reduce the weight and size of both the upper and lower frames. Since the pedestal has a circular cross section, the drag coefficient C _D of the pedestal is small, and the lateral external force acting on the pedestal can be made smaller than when the pedestal has a rectangular cross section.

[Brief explanation of the drawing]

Fig. 1 is a front view of an embodiment of the present invention, Fig. 2 is a view taken along the line A-A in Fig. 1, and the upper half of Fig. 3 is a view taken along the line B-B in Fig. 2, and the lower half is a view taken along the line B-B in Fig. 2. The left cross section is the view taken along line C-C in Figure 2, and the right cross section of the lower half is the second cross section.
Figure D-D line arrow view, Figure 4 is an explanatory diagram of the operation when the pedestal is raised, Figure 5 is an explanatory diagram of the operation when the pontoon is raised,
Fig. 6 is a front view of a self-elevating work platform supported on the seabed, Fig. 7 is a plan view of the same, Fig. 8 is a partially cutaway front view of a conventional lifting device, and Fig. 9 is a plan view of the same. ,
FIG. 10 is a front view of a self-elevating work platform that is subjected to external forces in sea areas with severe sea conditions, and FIG. 11 is a partially cutaway front view of another conventional device. 1... Pontoon, 2... Pillar, 3... Lifting device support frame, 5... Rack, 6... Upper frame, 7... Lower frame, 10a, 10b...
Locking piece, 12a, 12b...Bearing part, 15a, 1
5b... Cylinder for engaging and disengaging, 16a, 16b... Main vertical member, 19... Cylinder for lifting and lowering, 22... Center axis line.

Claims (1)

[Scope of utility model registration request] Racks are installed vertically at the front and rear of the pedestal that penetrates the pontoon, and an upper frame and a lower frame are provided on the pontoon, each having a locking piece that is fitted into the pedestal and engages with and disengages from the rack, and a cylinder for engaging and disengaging the locking piece. In a lifting device in which the upper and lower frames are connected by a cylinder for lifting and lowering, the pillars have a circular cross section, and the upper and lower frames each have a main body provided with bearings for supporting and guiding locking pieces on both outsides of the rack. The vertical member is installed vertically, and the lifting cylinder is connected to the opposing main vertical members of both the upper and lower frames so that the central axis of the lifting cylinder passes over the center axis of the locking piece that is easily engaged. Lifting device.