JPH01299197A - Hydraulic jack - Google Patents

Abstract

PURPOSE:To improve an operating property by linking a screw rod in parallel to the outer portion of a ram via a bracket, providing a gear on a lock nut, screwing the screw rod into a screw nut, and engaging a gear provided on the screw nut with the gear provided on the lock nut via a clutch gear. CONSTITUTION:As a ram 10 is lifted up, a screw rod 87 is interlockedly lifted up and, at this time, a screw nut 86 and a gear 84 which are screwed on the screw rod 87 are rotated. The rotation of this gear 84 is transmitted to a shaft 107 via a spur gear 103, and the shaft 107, a clutch 105 and a housing 108 are rotated in the same direction while further rotating a spur gear 104 which is attracted to the clutch 105 in the same direction, and the spur gear 104 rotates a lock nut 32 via a spur gear 36. Therefore, the lock nut 32 itself is kept in place. When the ram 10 is lowered, the screw rod 87 is also interlocked, merely rotating the screw nut 86, gear 84, clutch 105, spur gear 104 and lock nut 32 in the reverse direction to above without changing the position of the lock nut 32.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention is applicable to heavy equipment such as airplanes. This product relates to a hydraulic jack that lifts or lowers objects while supporting them.

(Conventional Technique #i) As a conventional hydraulic cylinder of this type, one shown in FIG. 4, for example, has been developed.

This hydraulic jack is composed of a cylinder 1, a ram 3 inserted into the cylinder 1 so as to be vertically movable via a piston 2, and a lock nut 5 screwed into a threaded portion 4 of the ram 3 outside the cylinder.

When the ram 3 is extended, pressure oil is introduced from the boat 6 to the lower pressure chamber 7 of the piston 2, causing the ram 3 and the lock nut 5 to rise.

To maintain the height of the ram 3 at a predetermined position, the lock nut 5 is lowered from the dotted line to the solid line position via the threaded portion 4, and the lower surface of the lock nut 5 comes into contact with the upper surface of the cylinder head la, locking the ram 3. It's the first time.

When lowering the ram 3, the lock nut 5 is rotated again to raise it to the dotted line position, and then the pressure oil in the pressure chamber 7 is released, and the ram 3 is lowered by its own weight.

(Problem to be solved by the invention) In the above hydraulic jack, the ram 3 is locked by rotating the lock nut 5 screwed onto the ram 3, so the lock nut 5 is rotated each time the ram 3 is raised or lowered. In addition, the positioning operation significantly reduces work efficiency and is dangerous because it is a manual operation.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a hydraulic jack that can automatically lock and position the ram and has good operability.

(Means for Solving the Problems) In order to achieve the above object, the present invention has a structure in which a ram is vertically movably inserted into a cylinder, and a lock nut disposed at the top of the cylinder or a screw formed on the outer periphery of the ram. In the hydraulic jack that is screwed into the housing, threaded rods are connected in parallel to the outside of the ram via a bracket, a gear is provided on the lock nut, and the threaded rod is mounted inside the screw nut rotatably supported by the housing. The gear is screwed onto the lock nut so as to be movable up and down, and the gear provided on the screw nut is freely engaged with the gear provided on the lock nut via a clutch gear.

(Function) When the ram is raised, the ratchet rod rises in conjunction with the ratchet rod. At this time, the ratchet nut and gear that are screwed onto the ratchet rod rotate, and this gear rotates through the gears of the clutch gear and lock nut. Since the lock nut is rotated by the ram, the lock nut itself is held in a fixed position, and when the ram is lowered, the screw rod also moves, and the screw nut, gear, clutch gear, and lock nut simply rotate in the opposite direction to the previous case. The position does not change,
The clutch gear is used to hold the ram in place.At this time, even if an external force is applied to the ram, the lock nut will not rotate and the ram will not move.

(Example) An example of the implementation of the present invention will be described below based on FIGS. 1 to 3.

First, details of the hydraulic jack main body A will be described.

As shown in FIG. 1, a ram 10 or 2 is inserted into a cylinder 9 via a piston 27 and a cylinder head 28 so as to be able to move up and down, and a pressure chamber 29 is defined below the cylinder 9. is selectively connected via a boat 30 to a pump or tank serving as a hydraulic pressure source.

For example, a right-handed male threaded portion 3 is provided on the outer periphery of the ram lO.
1 is formed, and this male threaded portion 31 is provided with a cylinder 2.
A female screw 33 of a lock nut 32 rotatably disposed above the lock nut 8 is screwed into the lock nut 32, and the lock nut 32 is used as a stopper for determining the position of the ram IO. rock nut 3
A flange-shaped spur gear 36 is formed on the upper part of 2.

A key groove 34 extending along the axial direction is formed in the ram 10, and a key 35 protruding from the inner periphery of the cylinder head 28 is fitted into this key groove 34 to guide vertical movement of the ram lO. .

A support plate 80 is provided at the top of the cylinder 9, and the ram 10 passes through this support plate 80.

An arbitrary gap 81 is provided between the lock nut 32 and the support plate 80 to prevent hook tension from occurring between the lock nut 32 and the support plate 80 when the lock nut 32 rotates.

The support plate 80 is provided with a hollow housing 99 parallel to the cylinder 9 and a bearing housing 82 .

Inside the bearing housing 82 is a self-aligning roller bearing 83.
The central body of the spur gear 84 is rotatably supported via the
The central body of the spur gear 84 is coupled to a ball nut 86 via a key 85 so as to be movable downward -L.

On the other hand, a ball screw shaft 87, which is a screw rod, is connected to a parallel bracket 37 provided on the ram IO via a universal joint 98. Ball screw shaft 8
7 is formed with a right-handed male thread 88 formed in the same direction as the male threaded portion 31 provided on the ram lO, and this screw 88 meshes with a female thread provided on the inner periphery of the ball screw nut 86. When the shaft 87 moves up and down, the ball nut 86 and the spur gear 84 rotate together.

Since the threaded portion 31 of the ram 10 and the male thread 88 of the ball screw shaft 87 are threaded in the same direction, the machining is standard machining, which is advantageous in terms of cost.

A shaft lot is rotatably supported by an L-shaped arm 102 fixed to a support frame 80 and a support plate 8o via a bearing 100°110.
A clutch gear 111 consisting of a second spur gear 103, an intermediate second spur gear 104, and a clutch 105 is attached.

The first spur gear 103 is connected to the shaft 10 through the key 112.
1 and a spur gear 8 of a ball screw nut 86.
4 is always engaged.

The second spur gear 104 is rotatably attached to the shaft lot via a bearing 107, and meshes with the spur gear 36 of the lock nut 32.

The clutch 105 has a casing 108 coupled to the shaft 101 via a key 113 and a solenoid 109 provided within the goose sink 108 via a bearing 114. Further, 116 is a lead wire.

A pin 115 is vertically inserted into the second spur gear 104 so as to be movable up and down.
09 is provided with a disk 106 that is attracted.

When moving the ram lO up and down, the solenoid 109 of the clutch 105 is energized by remote control in advance, and the disc 106 is
is drawn in, and the second spur gear 104 is connected to the casing 108.

Therefore, when the ram lO rises or falls, the bracket 37
Then, the ball pin shaft 87 moves up or down, and the ball pin nut 86 and spur gear 84 rotate.

The spur gear 84 connects to the shaft 10 via the first spur gear 103.
7, the shaft 107 and the housing 108 of the clutch 105 rotate in the same direction, and the clutch 105
The second spur gear 104 that is attracted to the lock nut 104 also rotates in the same direction, and the second spur gear 104 rotates the lock nut 32 via the spur gear 36.

If you want to hold the ram 10 in a desired position or to lock it in an emergency during expansion/contraction operation, demagnetize the solenoid 109 of the clutch 105 by remote control and stop the suction of the disk 106, then the clutch 105 and the second Spur gear 10
4 is released, the rotational force of the shaft 101 is no longer transmitted to the second spur gear 104 and the lock nut 32, and the lock nut 32 does not rotate but stops on the support plate 80.

When the clutch 105 is demagnetized, the disk 106 can be pushed upward by a return spring 117 or the like.

[Effect of the invention] According to the present invention, there are the following effects.

■When the ram is expanded or compressed, the ratchet rod moves up and down in conjunction, and the gear of the ratchet nut driven by the screw rod and the clutch gear rotate the locknut via the gear of the locknut. It is maintained in its original position regardless of vertical movement, and there is no need to manually move the lock nut up and down in response to the vertical movement of the ram, significantly improving work efficiency.

■The lock nut is automatically held in the same position according to the 7F movement of the ram, and does not require manual operation.

■If you want to hold the ram in place or lock it in an emergency, you can use remote control to free the clutch gear so that the movement of the bar is not transmitted to the lock nut, making the operation safe and smooth. .

- Due to the presence of the clutch gear, the gears on the lock nut and the gears on the screw nut have the same structure, which is advantageous in terms of cost since standard processing is possible.

■By changing the size of the clutch gear, the distance between the lock nut and screw nut can be reduced to 75g! It can be placed on the ground in any installation space.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view of the hydraulic jack according to the present invention, and FIG.
The figure is an enlarged sectional view of the clutch gear part in Figure 1, Figure 3 is a schematic plan view showing the meshing relationship between the lock nut gear, the screw nut gear, and the clutch gear, and Figure 4 is a diagram of the conventional hydraulic jack. FIG. (Explanation of symbols) 9...Cylinder 10...Ram 27...Piston 31...Threaded portion 32...Lock nut 36...Gear 37...Bracket 84
... Gear 86 ... Screw nut 87 ... Helical rod 99 ... Housing 103, 104 - ... Gear 105 ... Clutch 106 ... Disk 111
...Clutch gear Fig. 3 Fig. 40

Claims (1)

[Claims] In a hydraulic jack, a ram is inserted into a cylinder so that it can move up and down, and a lock nut placed at the top of the cylinder is screwed into a threaded part formed on the outer circumference of the ram. The rods are connected in parallel, a gear is provided on the lock nut, and the screw rod is screwed into the screw nut rotatably supported by the housing so as to be movable up and down, and the gear provided on the screw nut is locked via the clutch gear. A hydraulic jack that removably engages with a gear attached to a nut.