JPH0339956B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an improvement of a hydraulic jacking device using a hollow jack, in which the operating rod that moves up and down by the expansion and contraction of the hollow ram of the hollow jack is a screw rod, This invention relates to a jacking device that allows heavy objects to be lifted and lowered more safely and efficiently.

(Prior Art) Winches, chain blocks, and the like have traditionally been used for cargo handling, bridge construction, etc. in factories, wharves, and bridge construction work. However, in recent years, heavy objects that cannot be handled by these methods have been lifted.
There are more and more cases where people need to move.

In order to cope with these situations, the applicant of the present invention has previously developed a hydraulic jack for lifting and lowering as shown in Fig. 2, and has published it (Utility Model Publication No. 55-20717).

That is, in the lifting hydraulic jack shown in FIG. 2, the cylinder tube 30 of the hollow jack is fixed to the truck 31, and the piston rod 3
A nut case 33 is fixed to the upper end of the cylinder tube 2, and a nut case 34 is fixed to the lower end of the cylinder tube 30, respectively. And the cylinder tube 30
A tension rod 36 is inserted through both nut cases 33 and 34 and has recesses 35 formed at a predetermined pitch on its outer peripheral surface, and three-split lock nuts 37 and 38 are inserted into both nut cases 33 and 34. A tension rod 36, which suspends and supports a load, is supported and fixed by engaging the claw portion of the tension rod 36 into the recess 35.

Further, the claws of the three-split lock nuts 37, 38 and the recess 35 of the tension rod 36 rotate the rings 41, 42 via the handles 39, 40, and the wedge pieces 43, 44 lock the headed pin 45. ,4
By moving 6 outward, the engagement is released. That is, by pulling the headed pins 45, 46 outward to free the lock nuts 37, 38 from upward movement, the lock nuts 37, 38 can be moved upwardly.
38 and the recess 35 are released.

When lifting the load, the upper handle 39 is set to the engaged position, the lower handle 40 is set to the open position, and oil is supplied from the oil passage A to raise the piston rod 32 and the tension rod 36.
When the piston rod 32 rises to a predetermined position, the lower handle 40 is set to the engaged position, the upper handle 39 is set to the open position, oil is supplied from the oil passage B, the piston rod 32 is lowered, and the piston rod 32 is lowered to the same position as the beginning. The piston rod 32 is raised by operation.

The lifting hydraulic jack shown in FIG. 2 can move heavy objects up and down relatively easily and with high efficiency, and has excellent practical utility.

However, there are still many problems that need to be solved with this lifting hydraulic jack.

The first problem is that it is difficult to significantly increase the supporting and fixing force of the tension rod 36. That is, three-part lock nut 37,3
The tension rod 36 is supported and fixed by the engagement of the claw part 8 with the recess 35 on the outer circumferential surface of the rod, and the handles 39 and 40 are operated by input, and the headed pin is attached via the wedge pieces 43 and 44. 45, 46
By pulling the lock nuts 37 outward, the engagement between the two is disengaged.
If the engagement area between the claw portion 38 and the recess 35 is increased, the operation of the handle for disengaging the engagement will inevitably become heavier and the operability will deteriorate.

Therefore, the engagement area between the claw portion and the recess 35 is:
It is difficult to significantly increase this, and as a result,
There is also a certain limit to the supporting and fixing force of the tension rod 36, and as the load becomes even larger, safety and operability will deteriorate.

The second problem is that workability is relatively poor. As mentioned above, when lifting and lowering the tension rod 36 under load, it is necessary to manually set the upper handle 39 and the lower handle 40 in addition to switching the oil supply system, which requires a large number of workers. Moreover, it takes time to set the handle, resulting in a decrease in work efficiency.

The third problem is the three-split rock nut 37,3
8 and the tension rod 36 are severely damaged, requiring a lot of effort to repair. As mentioned above, a large load is supported and fixed by the engagement between the claws of the three-split lock nuts 37 and 38 and the recess 35 on the rod 36 side, and the engagement and disengagement are performed under load. Since the tensioning is performed at the bottom, the claws and recesses 35 are likely to be damaged, resulting in rattling during operation or a reduction in the supporting and fixing force of the tension rod 36.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned problems in the conventional lifting hydraulic jack using a so-called hollow jack, namely, the claws of the three-split lock nuts 38 and 39 and the recess 36 of the rod 36. It is difficult to increase the engagement area with the tension rod 36, and it is not possible to significantly increase the supporting and fixing force of the tension rod 36 under load. This solves problems such as the lack of workability due to the need for both switching operations of the oil supply system, and the frequent damage to the three-split lock nuts 38, 39 and rod 36, which require frequent repairs. The tension rod that supports the load is a screw rod with a thread formed on its outer circumferential surface, and the screw rod is supported and fixed by "threaded engagement" between the screw rod and a nut screwed into it. At the same time, the "threaded engagement" between the nut and the screw rod is released by hydraulic pressure, that is, the nut is rotated idly with respect to the screw rod, thereby reducing the supporting and fixing force of the screw rod under load. The present invention provides a jacking device that makes it possible to improve the safety of jacks and jacks, improve the operability and work efficiency of jacks, and reduce damage to jacks and the frequency of repair.

(Means for Solving the Problems) The present invention provides a socket-shaped upper holder which is fixed to the tip of the hollow ram 5 of the hollow jack 1 and has an inverted conical nut restraint part formed in a hole passing through the center thereof. a stand 6; a hollow cylinder 2 of the hollow jack 1;
a socket-shaped lower holding table 3 fixed to the lower end of the hollow ram 5 and having an inverted conical nut restraining part formed in a hole penetrating the center thereof; Screw rod 15 is inserted into the rod and is movably arranged in a state in which it is prevented from rotating in the vertical direction, and has a coarse thread formed on its outer peripheral surface.
The thrust bearing 11 is disposed within the inverted conical nut restraining portion of the upper holding base 6 while being screwed onto the screw rod 15, and the thrust bearing 11 is interposed by a cap disposed with a slight gap from the upper surface side. and an inverted conical upper nut 10 enclosed in the inverted conical nut restraining portion; a thrust bearing 9 is disposed below the upper nut 10, and the upper nut 10 is slightly pushed up. The upper annular piston 7 holds the upper nut 10 in a state where it can freely rotate between the upper slite bearing 11 and the lower thrust bearing 9 by releasing the restraint between the nut outer wall surface and the nut restraining part inner wall surface.
The thrust bearing 20 is screwed onto the screw rod 15 and is disposed within the inverted conical nut restraining portion of the lower holding base 3, and is disposed with a slight gap from the upper surface of the lower cap 21. An inverted conical lower nut 19 is interposed and enclosed in the inverted conical nut restraint part; A thrust bearing 18 is disposed below the lower nut 19, and the lower nut 19 is slightly a lower annular piston 16 that holds the lower nut 19 in a freely rotatable state between the upper thrust bearing 20 and the lower thrust bearing 18 by pushing up and releasing the restraint between the outer wall surface of the nut and the inner wall surface of the nut restraining portion; This is the basic structure of the invention.

(Function) When lifting a heavy object, oil is sent from the oil port A to push up the ram 5. At this time, the upper nut 10
is restrained by the nut restraining portion of the upper holding stand 6, and the screw rod 11 is held and fixed to the upper holding stand 6 via the upper nut 10. Further, the lower nut 19 is held so as to freely rotate by being slightly lifted, and rotates idle as the screw rod 11 rises.

The ram 5 is lowered by supplying oil from the oil port B. When the ram 5 is lowered, the lower nut 19 is restrained, and the screw rod 15 is fixedly held on the lower holding base 3, while the upper nut 10 is released from its restraint and rotates idly as the ram 5 lowers.

On the other hand, when a heavy object is to be lowered, oil is supplied from the oil passage 8 to operate the upper annular piston 7 and release the upper nut 10. Also, oil is sent from the oil port A to raise the ram 5. As the ram 5 rises, the upper nut 10 idles, and the screw rod 15 is held and fixed by the lower holding base 3 via the lower nut 19.

Next, the oil supply from the oil passage 8 is stopped, and the oil is supplied from the oil passage 17. As a result, the lower nut 19 is released, the upper nut 10 is restrained, and the screw rod 15 is held and fixed by the upper holding base 6. In this state, oil is supplied from the oil port B and the ram 5 is lowered. At this time, the lower part Natsu 17 was released from restraint.
rotates idly as the screw rod 15 descends.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

FIG. 1 is a longitudinal sectional view of the jacking device according to the present invention, in which 1 is a hollow jack, 2 is a hollow cylinder, 3 is a socket-shaped lower holding base, and 4 is a hollow jack.
5 is a hollow guide, 5 is a hollow ram, 6 is a socket-shaped upper holding base, 7 is an upper annular piston, 8 is an oil passage,
9 and 11 are thrust bearings, 10 is an upper nut, 12 is an upper cap, 13 is a spring, 1
4 is a key, and 15 is a screw rod.

Further, 16 is a lower annular piston, 17 is an oil passage,
18 and 20 are thrust bearings, 19 is a lower nut, 21 is a lower cap, 22 is a key, 23 is a spring, 24 is a rotation stopper, and 25 is a cylinder pressure.

The hollow jack 1 is formed of a hollow cylinder 2, a hollow ram 5, a hollow guide 4, etc., and the bottom of the hollow cylinder 2 is screwed onto a lower holding base 3.

The lower holding stand 3 is formed in the shape of a so-called socket with different diameters, and is fixed to a workpiece pedestal or the like by an appropriate method. Further, an inverted conical nut restraining portion is formed in the middle of the through hole of the socket-shaped lower holding base 3, and a lower nut 19 screwed onto the screw rod 15 is held here as described later. Ru.

A hollow guide 4 is disposed at the center of the interior of the hollow cylinder 2, and a hollow ram 5 is provided between the outer wall surface of the hollow guide 4 and the inner wall surface of the hollow cylinder 2, and slides between the two in an oil-tight state. is installed.

The tip of the hollow ram 5 projects slightly outward from the hollow cylinder 2, and an upper holding table 6 is screwed onto this.

The upper holding stand 6 is formed in the shape of a socket with different diameters, which is substantially the same as the lower holding stand 3, and an inverted conical nut restraining portion is formed in the middle of the through hole. Further, an upper annular piston 7 is fitted to the bottom of the upper holding table 6 in an oil-tight manner.
The oil chamber of the upper annular piston 7 is communicated with the outside through an oil passage 8.

A thrust bearing 9 is disposed above the annular piston 7, and an inverted conical upper nut 10 screwed onto a screw rod 15, which will be described later, is placed above the thrust bearing 9.

The inverted conical upper nut 10 has almost the same form as the inverted conical nut restraint part of the upper holding base 6, and when a downward load is applied via the screw rod 15, the upper nut 10 As shown in FIG. 1, the outer wall surface of the upper nut 10 and the inner wall surface of the nut restraining portion are in contact with each other, and the nut is restrained and held within the upper holding base 6. Further, the upper part of the upper nut 10 is closed by an upper cap 12 in addition to a thrust bearing 11 and a spring 13 interposed therebetween.

Incidentally, a small gap is provided between the upper cap 12 fixed above the upper holding base 6 and the upper surface of the upper nut 10 and the upper surface of the thrust bearing 11, respectively. When the upper annular piston 7 is actuated, the upper nut 10 is pushed upward slightly. the result,
The upper nut 10 separates from the nut restraining portion of the upper holding base 6, is released from the restraint, and rotates idly as the hollow ram 5 rises.

The screw rod 15 has a hollow guide 4 and an upper
It is disposed vertically through the insertion holes of the lower holding parts 6 and 3, and has coarse threaded screws formed on its outer peripheral surface. In addition, the screw rod 15
A vertical keyway is formed on the outer wall of the
A key 14 installed in the upper cap 12 is fitted into this keyway, and the screw rod 15 is thereby prevented from rotating.

Incidentally, the relative movement between the screw rod 15 and the ram 5 is achieved by operating the upper annular piston 7 to release the upper nut 10 from the upper holding base 6 and to allow the upper nut 10 to freely rotate as described above. This becomes possible.

The lower annular piston 16 is fitted into the bottom of the lower holding table 3 in an oil-tight manner, and its oil chamber is connected to the oil passage 1.
It is communicated to the outside through 7. Further, a thrust bearing 18 is disposed above the lower annular piston 16, and a lower nut 1 is mounted on the thrust bearing 18.
9 is placed.

The inverted conical lower nut 19 is connected to the upper nut 1.
It has almost the same form as 0, and the screw rod 1
5 and is held within the nut restraining portion of the lower holding base 3.

That is, by applying a downward load through the screw rod 15, the lower nut 19 is brought into a state where the outer wall surface of the upper nut 19 and the outer wall surface of the nut restraining portion of the lower holding base 3 are in contact with each other, as shown in FIG. Thus, it is restrained and held within the lower holding table 3.

The upper part of the lower nut 19 is closed by a lower cap 21 with a thrust bearing 11 and a spring 23 interposed therebetween, and between the lower cap 21 and the upper surface of the lower nut 19 and the upper surface of the thrust bearing 20, Upper nut 10
As in the case of , a small gap is provided in each case. That is, by providing this gap, the upper nut 19 is pushed up slightly when the lower annular piston 16 is operated, and as a result, the lower nut 19 is separated from the nut restraining portion of the lower holding base 3 and is unrestrained, and the screw rod 15 The machine spins idly as it descends.

A screw rod 15 is attached to the lower cap 21.
A key 22 is provided which fits into the long groove of the screw rod 15, thereby preventing the screw rod 15 from rotating.

Further, the lower cap 21 is attached to the lower holding base 3.
The hollow guide 4 is fitted into a step formed in a through hole, and its rotation is stopped by a rotation stopper 24, and is fixed by being pressed by a cylinder bottom 25 onto which the hollow guide 4 is screwed.

Next, the operation of the jacking device will be explained.

When lifting a load, feed oil from oil port A,
The hollow ram 5 is raised along the guide 4 and the upper holding table 6 is pushed up. At this time, the upper nut 10 in the upper holding base 6 is restrained by its nut restraining portion, and a lifting force is applied to the screw rod 15 via the upper nut 10.

In addition, since the upper nut 10 is screwed into the screw rod 15, the load at the time of lifting is equally shared over the entire length of the threaded part of the two screws. Compared to the case of engagement,
Extremely stable load support is possible.

On the other hand, the lower nut 19 is screw rod 1.
As the screw rod 5 rises, it separates from the nut restraining portion of the lower holding stand 3, and at a position raised by approximately the gap against the spring 23, it idles as the screw rod 15 rises. Also, the screw rod 15 is the key 1
4 and 22, and the hydraulic oil in the cylinder 2 flows back into the tank (not shown) from the oil port B.

When the hollow ram 5 reaches the end of its upward stroke, the oil supply is switched and pressure oil is sent from the oil port B to push the ram 5 down. As a result, the lower nut 19, which has been pulled up by approximately the gap, descends into the nut restraining portion of the lower holding base 3, and is held in a restrained state. That is, by holding the lower nut 19 in a non-rotatable state, the screw rod 15 is held and fixed to the lower holding base 3, and the load is stopped at that position.

When the ram 5 descends and the upper holding table 6 descends,
The upper nut 10 separates from the nut restraining portion and rises by the gap, and idles as the upper holding table 6 descends.

When the ram 5 descends to the initial position, the oil feeding direction is switched to the initial state, and the ram 5 is operated to rise again. In this way, by repeating the operation of sequentially switching the oil feeding direction, the heavy object is lifted.

Next, when lowering a heavy object, first, pressure oil is sent to the oil passage 8 to operate the upper annular piston 7, and the upper nut 10 is slightly pushed up to make it freely rotatable. As a result, the load is applied to the lower nut 19.
The lower nut 19 is held and fixed to the lower holding base 3 through the lower nut 19, and the lower nut 19 is held in a restrained state.

Next, pressurized oil is sent from the oil port A to raise the ram 5. At this time, since the upper nut 10 is held in a state where it can freely rotate as described above by the operation of the upper annular piston 7, it idles as the ram 5 rises, and the ram 5 rises smoothly.

When the ram 5 reaches the stroke end, oil supply to the oil passage 8 and oil port A is stopped. This results in Ram 5
stops rising, and the upper nut 10 is in a state where it can be restrained and held by the nut restraining portion of the upper holding base 6.

Next, pressure oil is sent to the oil port 17 to operate the lower annular piston 16 to release the restraint of the lower nut 19, and pressure oil is sent from the oil port B to lower the ram 5. As a result, the load is held and fixed to the upper holding base 6 via the upper nut 10, and the lower nut 1
The ram 5 is lowered by the idle rotation of the ram 9.

When the ram 5 is lowered to a predetermined position, the supply of pressure oil is switched to the oil path 8 and the oil port A side, and the ram 5 is raised by the same operation as the beginning.

As described above, the heavy object is lowered by sequentially switching the direction in which the pressure oil is fed to the upper and lower annular pistons 7, 16 and the hollow cylinder 2.

(Effects of the Invention) In the present invention, an upper holding stand 6 is fixed to the upper end of the hollow ram 5 forming the hollow jack 1, and a lower holding stand 3 is fixed to the lower end of the hollow cylinder 2. The screw rod 15 is inserted through the upper and lower holding stands 6 and 3, and an inverted conical upper nut 10 and a lower nut 19 are screwed into the screw rod 15.
The structure is such that the load applied to the screw rod 15 is supported by holding the nut 19 in the nut restraining part of the upper holding table 6 and the lower nut 19 in the nut restraining part of the lower holding table 3, respectively.

As a result, the load applied to the screw rod 15 is
The screw rod 15 and the upper nut 10 or the lower nut 19 will be held evenly by the entire thread length of the threaded part, making it possible to hold a larger load safely and reliably, as well as preventing the previous division. Unlike jacking devices that use nuts, there is no damage to the tension bar or rattling due to damage to the claws of split nuts.

Further, in the present invention, the upper nut 10 and the lower nut 19 are disposed so as to be movable upward by a small gap within the upper holding stand 6 and the lower holding stand 3, and both nuts 10, 19 When the restraint is released, both nuts 10 screwed into the screw rod 15,
19 is held so that it can freely rotate.

As a result, when lifting heavy objects, the ram 5
At the same time as the ram 5 is raised, the screw rod 15 is held and fixed by the upper holding table 6 and the screw rod 15 is released from being held by the lower holding table 3, and at the same time as the ram 5 is lowered, the holding of the screw rod 15 by the upper holding table 6 is released. The holding and fixing of the screw rod 15 by the lower holding table 3 are automatically performed, and lifting of heavy objects is extremely simple by simply switching the supply of pressure oil to the oil ports A and B of the hollow jack 1. Moreover, it can be performed with high efficiency.

In addition, in the present invention, the upper annular piston 7 and the lower annular piston 16 are disposed at the inner bottoms of the upper holding table 6 and the lower holding table 3, respectively, and the operation of both the annular pistons 7 and 16 causes the upper nut 10 and the lower nut to be rotated. The nut 10, 19 is held in both the holding parts 6, 3 so as to be able to freely rotate by releasing the restraint of the nut 19.

As a result, even when lowering a heavy object, oil is sent to the oil path A of the hollow jack 1 and the oil path 8 for the upper annular piston 7, and oil is sent to the oil path B and the oil path 17 for the lower annular piston 16. By alternately switching between oil and oil, the screw rod 1 is
The holding and fixing of the screw rod 15 by the upper holding table 6 and releasing the holding of the screw rod 15 by the lower holding table 3 can be automatically and alternately performed. It is possible to lower heavy objects extremely smoothly and safely.

As mentioned above, the present invention does not require any complicated turning device for the upper and lower nuts or an electric control device for the nut turning device, and can lift heavy objects by simply changing the supply direction of pressure oil. In addition, it is possible to descend automatically, safely and with high efficiency, and exhibits excellent practical utility.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a jacking device according to the present invention. FIG. 2 is a longitudinal section of a conventional lifting hydraulic jack. A, B...Cylinder oil port, 1...Hollow jack, 2...Hollow cylinder, 3...Lower holding stand, 4
...Hollow guide, 5...Hollow ram, 6...Upper holding stand, 7...Upper annular piston, 8...Oil passage,
9, 11... Thrust bearing, 10... Upper nut, 12... Upper cap, 13, 23...
Spring, 14, 22... Key, 15... Screw rod, 16... Lower annular piston, 17...
Oil passage, 18, 20... Thrust bearing, 19
...Lower nut, 21...Lower cap, 24...
...Stop rotation, 25...Cylinder bottom.

Claims (1)

[Claims] 1 A socket-shaped upper holding base 6 fixed to the tip of the hollow ram 5 of the hollow jack 1 and having an inverted conical nut restraint part formed in a hole passing through its center.
a socket-shaped lower holding stand 3 fixed to the lower end of the hollow cylinder 2 of the hollow jack 1 and having an inverted conical nut restraining part formed in a hole passing through the center thereof; the hollow ram 5 and the upper holding stand 3;・Lower holding stand 6,
a screw rod 15 which is inserted through the hole of No. 3 and is movably disposed in a state where it is prevented from rotating in the vertical direction, and has a coarse thread formed on its outer peripheral surface; A cap 1 is disposed within the inverted conical nut restraining portion of the upper holding base 6, and is disposed with a slight gap from the upper surface side thereof.
2, an inverted conical upper nut 10 is enclosed in the inverted conical nut restraining portion with a thrust bearing 11 interposed; a thrust bearing 9 is disposed below the upper nut 10; By slightly pushing up the upper nut 10 and releasing the restraint between the nut outer wall surface and the nut restraining part inner wall surface,
an upper annular piston 7 that holds the upper nut 10 in a freely rotatable state between the upper thrust bearing 11 and the lower thrust bearing 9; An inverted conical nut restraint part is disposed in the inverted conical nut restraint part, and is enclosed in the inverted conical nut restraint part with a thrust bearing 20 interposed by a lower cap 21 disposed with a slight gap from the upper surface side of the lower cap 21. A lower nut 19 is disposed below the lower nut 19 with a thrust bearing 18 interposed therebetween, and the lower nut 19 is slightly pushed up to release the restraint between the outer wall surface of the nut and the inner wall surface of the nut restraining portion. A jacking device comprising a lower annular piston 16 that holds a nut 19 in a state where it can freely rotate between a thrust bearing 20 above it and a thrust bearing 18 below it.