JPH04308196A - Hook claw device for lifting hydraulic jack - Google Patents

Abstract

PURPOSE:To provide a hook claw device with excellent lifting speed and safety by providing a coupling block moving member simultaneously moving coupling blocks along slant guide holes in the inward radial direction and outward radial direction via the feed/discharge of the pressure oil stored in a vertical moving cylinder member. CONSTITUTION:A hook claw block group 1 circularly arranged with fan-shaped hook claw blocks 2 is slid on slant guide holes formed at a down gradient in the outward radial direction into the umbrella bone shape at a uniform interval in a hook claw device main body 3 to be coupled with the hook step 01 of a guide rod 02, the hook claw blocks 2 and release cams 8 are integrally assembled with proper gaps, and two stanchions 6 are loosely slidably inserted in the gaps. The hook claw blocks 2 are coupled with the hook step 01 when the hook claw blocks 2 are pushed up by pressing plates 7 via a hollow piston 4 pushed up by a compression spring 5 and the stanchions 6, and the hook claw blocks 2 are pulled down and released when the device main body 3 is slightly lifted then pressure oil is fed from an oil feed/discharge port 10 to push the hollow piston 4 down.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a locking claw device for a hydraulic jack for lifting and lowering.

0002

[Prior art] Hydraulic jacks for lifting heavy objects include:
Conventionally, for example, as shown in the vertical cross-sectional view of FIG.
The one published in No.-45858 is known. That is, in the figure, the jack includes a fixed vertical guide rod 02 that extends in the vertical direction and has a plurality of locking stages 01 formed at appropriate intervals, and an inner cylinder 03 that is coaxially inserted into the center of the fixed vertical guide rod 02. and a cylindrical piston 06 that is inserted between the outer cylinder 04 that surrounds the central cylinder 07 and can move in the vertical direction; It is mainly formed of an upper cylinder 09 through which the guide rod 02 passes through the center hole, and a lower cylinder 010 which is connected to the lower end of the piston 06 of the central cylinder 07 and through which the guide rod 02 passes through the center hole. Here, 011,012
013 and 014 are the upper and lower oil supply and drainage ports of the central cylinder 07, respectively.
, a frusto-conical spring chamber formed at the bottom of the lower cylinder 010, 015,016 having a spring 01 at the top thereof.
7,018 and a truncated conical locking pawl with a center hole that is pressed through the bottom plates 019,020 and through which the guide rod 02 is inserted; 021,022 are the upper parts of the upper cylinder 09 and lower cylinder 010, respectively; A hollow piston rod that is inserted into pressurized chambers 023 and 024 formed in the center and has a piston protruding from its center.
2 are inserted, and the lower ends thereof are in contact with the upper ends of the locking claws 015 and 016, respectively. 029 and 030 are respectively pressurized chambers 0
23 are the upper oil supply and drainage ports, the lower oil supply and drainage ports, 031 and 032 are the upper oil supply and drainage ports and the lower oil supply and drainage ports of the pressurizing chamber 024, respectively.
033 is a load suspended from the lower end flange 034 of the central cylinder 07 via a hanger 035.

However, in such a device, the locking pawl 015 or 0 that fits into the guide rod 02 is required to move up and down.
16, use the hollow piston rod 021 or 022.
Since it is necessary to drive the locking pawl 015 or 016 away from the locking position, this takes extra time and has the disadvantage that the jack's lifting speed becomes slower.

[0004] Therefore, the present applicant first filed a patent application No. 2-4.
11478, we proposed a "hydraulic jack for lifting." That is, as shown in the longitudinal cross-sectional view of FIG. 8, a vertical guide rod 037 in which notches 036 are recessed in multiple stages at appropriate intervals in the axial direction is connected to a vertical guide rod 037 from an upper locking cylinder 038, a central cylinder 039, and a lower locking cylinder 040. In a hydraulic jack for lifting and lowering in which an elevator is coaxially inserted, an upper half cylinder 041 and a lower half cylinder 04
2 is vertically symmetrically connected to the central cylinder 03.
9, upper half cylinder 041 and lower half cylinder 04
2, an upper locking cylinder 038 connected to the hollow piston 044 of the upper half cylinder 041, and a lower half cylinder 04.
A lower locking cylinder 040 connected to a hollow piston 045 of 2, an upper locking cylinder 038, and a lower locking cylinder 040 are arranged respectively, and are raised and lowered diagonally by the raising and lowering of the hollow pistons 046 and 047, and a notch 036 is formed at the inner lower corner. It is equipped with a locking claw 048 that is fitted into and removed from the holder. However, in such a device, the locking pawl 048 touches the notch 0 of the guide rod 037 under load.
There is a risk that he will fall out of 36.

[0005]

[Problems to be Solved by the Invention] The present invention has been proposed in view of the above circumstances, and it is an object of the present invention to provide a lifting hydraulic system which has a short fitting/disconnecting time, ensures reliable fitting/disconnecting, and is therefore superior in lifting speed and safety. An object of the present invention is to provide a locking pawl device for a jack.

[0006]

[Means for Solving the Problems] To achieve this, the present invention provides a fixed guide in which a plurality of annular step-shaped locking steps are formed by cone portions that are arranged at appropriate intervals on a vertical support and that gradually reduce the shaft diameter at the bottom. In a locking pawl device for a hydraulic jack for lifting, a pair of upper and lower movable cylindrical members each having a built-in fitting/dismounting block are inserted into the rod, and both movable cylindrical members are alternately moved, coaxially with the locking stage of the guide rod. It has a sloped top surface and a sloped bottom surface which are arranged at equal intervals and are parallel to each other and slope downward in the outward radial direction, and has a sloped surface that abuts the cone part at the inner end, and further has an inner end of each of the sloped bottom surfaces. A plurality of engaging blocks each having a horizontal bottom surface at a corner portion thereof, and a center hole that is fitted onto the fixed guide rod, extending downwardly in an outward radial direction at equal intervals in the center hole, and each having the above-mentioned engaging blocks therein. A vertically movable cylindrical member having a plurality of inclined guide holes built into the vertically movable cylindrical member so as to be freely slidable, and a pressurized oil built into the vertically movable cylindrical member, which simultaneously moves each of the above-mentioned engaging blocks in the inward radial direction and the outward radial direction. The present invention is characterized by comprising an engagement block moving member that moves along the inclined guide hole.

[0007]

[Operation] When the locking pawl is fitted to the guide rod, if the load acting on it is F, then the locking pawl block is Fco
Push the guide rod with a force of sQ2 ・sinQ2. In addition, the upward force of the compression spring acting on the locking pawl block is P
1, the locking claw block is P1 cosQ3 ・
Push the guide rod with a force of sinQ3. Furthermore, when the locking pawl block is detached from the guide rod, if a pressing force P2 is applied to the detachment cam by hydraulic pressure, the locking pawl block is separated from the guide rod by a force of P2 cosQ3 ・sinQ3; is the above force FcosQ2
- Designed to be smaller than sinQ2, so even if there is an erroneous signal during mating, disengagement will not occur. When the locking pawl block is detached from the guide rod, the minimum lifting amount of the locking pawl block can be small due to its shape.

[0008]

[Embodiment] An embodiment of the present invention will be explained with reference to the drawings. The same reference numerals as in FIG. This is a group of locking pawl blocks in which the fan-shaped locking pawl blocks 2 are arranged in a substantially annular manner in cooperation with each other. By sliding into the inclined guide hole, it can be fitted into and removed from the locking stage 01 of the guide rod 02. 4 is a hollow piston inserted into the upper end of a compression spring 5 elastically loaded in the center hole at the bottom of the device body 3;
Reference numeral 6 denotes a plurality of columns whose lower ends are fixed to the shoulders of the upper end of the hollow piston 4 at equal intervals. An arc-shaped push plate 7 that is slidable on the outer peripheral surface is supported at both ends with an upward slope in the outward radial direction. Reference numeral 8 designates a detachment cam fixed to the locking pawl block 2 via a plurality of stud bolts 9 passing through elongated holes, and reference numeral 10 designates an oil supply/drainage port for supplying and discharging pressurized oil to the outer peripheral surface of the hollow piston 4. Next, Figure 2 is a partially enlarged view and Figure 3
In the plan view, 11 is the horizontal bottom surface of the locking pawl block 2 that comes into contact with the locking stage 01 of the guide rod 02. Reference numeral 13 denotes the inner peripheral surface of the locking pawl block 2 that comes into contact with the cone guide portion 035a of the guide rod 02, and this has a steep upward slope in the outward radial direction. Reference numeral 15 denotes a sloped top surface of the locking pawl block 2 that receives a load from the device main body 3, and this slopes downward in the outward radial direction. 16 is the locking claw block 2
This is a sloped bottom surface that is continuous with the horizontal bottom surface 11 of , and is parallel to the sloped top surface 15 . Reference numeral 17 denotes an outer circumferential surface of the locking pawl block 2 that forms a sliding surface with the push plate 7, and this has an upward slope in the outward radial direction.

In such a device, the locking pawl block 2 and the release cam 8 are integrally assembled with stud bolts 9 with an appropriate gap between them, and the two adjacent columns 6 are loosely slid into this gap. The guide rod 02 of the locking pawl block 2 is inserted into the locking stage 01 in a manner that the locking step 01 can be freely accessed.
As shown in the right half of FIG. 1, this is done by pushing up the locking pawl block 2 by the push plate 7 via the hollow piston 4 pushed up by the compression spring 5 and the column 6. Furthermore, in order to detach the guide rod 02 of the locking pawl block 2 from the locking stage 01, as shown in the left half of FIG. 1 and the partially enlarged view of FIG. Figure 5 a)
After being raised, pressurized oil is supplied from the oil supply/drainage port 10 to the lower end flange of the hollow piston 4, and the hollow piston 4 is pushed down against the compression spring 5 and locked via the support column 6, push plate 7, etc. This is done by pulling down the claw block 2. The mechanical relationship in each of the above states is shown in the partially enlarged view of FIG.
Since the guide rod is pressed with a force of cosQ2 ・sinQ2, the locking pawl block 2 cannot be released unless more than this force is applied.Therefore, the output of the release device is a pressing force calculated using the minimum value of the load F as the jack's own weight. In addition, the outer peripheral surface 1 of the locking claw block 2 of the compression spring 5
7, the locking claw block 2 moves to P1 c
Push the guide rod with a force of osQ3 ・sinQ3. Also, when detaching, a pressing force P2 is applied to the detachment cam 8 by hydraulic pressure.
acts, the detachment cam 8 becomes P2 cosQ3 ・si
An attempt is made to release the locking pawl block 2 in the outward radial direction with a force of nQ3, but this force is equal to the above force FcosQ2
- Since it is designed to be smaller than sinQ2, the locked state is maintained even if a detachment signal is accidentally applied during fitting, and the locking pawl block 2 will not separate from the locking step 01. To remove this locking claw block 2, first receive the load F with the lower locking claw block (Fig. 6), and then move the device body 3 a.
When the upper locking claw block 2 is lifted by 1, the guide rod pressing force FcosQ2 ・sinQ2 becomes zero, so the upper locking claw block 2 can be removed by its own weight alone, and the minimum lifting movement at that time is a is the angle Q
The dimensions are determined by 2. The vertical cross-sectional view in FIG. 6 shows an elevating device formed by connecting this locking pawl device to the upper and lower ends of a hydraulic jack 18, respectively, and coaxially attaching it to the guide rod 02, where 19 is an elevating floor.

According to the device of the embodiment, a plurality of locking pawl blocks each having a fan-shaped planar shape are disposed coaxially and capable of coming into contact with the locking step of the guide rod, and A sloped top surface and a sloped bottom surface forming a part of the pawl block, parallel to each other and sloping downward in the outward radial direction, a horizontal bottom surface formed at the inner circumferential end of each of the sloped bottom surfaces, and each of the above-mentioned engagements. Since a plurality of columns each having a mechanism for sliding the pawl block in the radial direction and a compression spring on which a hollow piston supporting each column is mounted are provided, the following effects can be achieved. (1) When the locking pawl is fitted to the guide rod, if the load acting on it is F, then the locking pawl block is Fco
The guide rod is pressed with a force of sQ2 ·sinQ2, so the fitting is highly reliable and safety is improved. (2) Also, when the locking pawl block is fitted to the guide rod, if the upward force of the compression spring acting on it is P1, then the locking pawl block is P1cosQ3 ・sinQ
3. The guide rod is pressed with a force of 3.5 mm, which further increases the reliability of the fit and improves safety. (3) When detaching the locking pawl block from the guide rod, the load F is received by the locking pawls of other lifting hydraulic jacks, and then safety is improved. (4) Furthermore, when the locking pawl block is detached from the guide rod, if a pressing force P2 is applied to the detachment cam using hydraulic pressure, the locking pawl block will move P2 cosQ3 ・sinQ3
is pulled away from the guide rod by a force, but this force is designed to be smaller than the above force FcosQ2 ・sinQ2. Therefore, even if there is an erroneous signal during mating, separation will not occur, improving safety. . (5) Furthermore, when the locking pawl block is detached from the guide rod, the minimum amount of lifting movement of the locking pawl block is small due to its shape, and therefore the lifting speed is improved. (6) According to the device shown in FIG. 6 in which the locking pawl device of this embodiment is applied to the lifting hydraulic jack proposed earlier by the applicant, the lifting operation becomes continuous and the safety is improved. The uses of the device will expand.

[0011]

In short, according to the present invention, the fixed guide rod is fitted into a fixed guide rod in which a plurality of annular step-shaped locking steps are formed by cone portions that are arranged at appropriate intervals on a vertical support and whose lower shaft diameters are gradually reduced. In a locking pawl device for a hydraulic jack for lifting, in which a pair of upper and lower movable cylindrical members with a built-in deblocking member are externally inserted, and both movable cylindrical members are alternately moved, the locking pawls are coaxially aligned with the locking step of the guide rod at equal intervals. The slanted top surface and the slanted bottom surface are arranged parallel to each other and slope downward in the outward radial direction, and the slanted surface abuts the cone part at the inner end, and further has an slanted surface at the inner end corner of each of the slanted bottom surfaces. It has a plurality of engaging blocks each having a horizontal bottom surface, and a center hole that is externally inserted into the fixed guide rod, and extends downwardly in the outward radial direction at equal intervals in the center hole, and each of the engaging blocks can freely slide inside the center hole. a vertically movable cylindrical member having a plurality of inclined guide holes built into the vertically movable cylindrical member; and a vertically movable cylindrical member built into the vertically movable cylindrical member which simultaneously moves each engagement block in the inward radial direction and outward radial direction by supplying and discharging pressurized oil. By providing an engaging block moving member that moves along the vertical axis, it is possible to obtain a locking pawl device for a hydraulic jack for lifting, which has a short fitting/unclosing time and reliable fitting/unclosing, and therefore has excellent lifting speed and safety. , the present invention is extremely useful industrially.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is a partially enlarged view showing a fitted state of the locking claw block of FIG. 1;

FIG. 3 is a partial plan view of FIG. 2;

4 is a partially enlarged view showing a detached state of the locking pawl block of FIG. 1; FIG.

5 is a partially enlarged view illustrating the dynamic relationship of forces acting on the locking pawl block of FIG. 1; FIG.

FIG. 6 is a longitudinal cross-sectional view showing a lifting device to which the locking pawl device of the present invention is applied.

FIG. 7 is a longitudinal cross-sectional view showing a known lifting hydraulic jack.

FIG. 8 is a longitudinal cross-sectional view showing the "lifting hydraulic jack" proposed earlier by the present applicant.

[Explanation of symbols]

1 Locking claw block group 2 Locking claw block 3　Device body 4 Hollow piston 5 Compression spring 6 Pillar 7 Push plate 8 Detachment cam 9 bolts 10 Oil supply and drain port 11 Horizontal bottom surface 13 Inner peripheral surface 15 Slanted top surface 16 Slanted bottom surface 17 Outer peripheral surface 18 Hydraulic jack 19 Elevating floor 01 Locking stage 02 Guide rod 035a Cone guide part a Minimum movement amount F Load P1 Push-up force P2 Pressing force Q1 Angle Q2 Angle Q3 Angle

Claims (1)

[Claims] [Claim 1] Upper and lower parts 1 in which a fitting/disengaging block is built into a fixed guide rod in which a plurality of annular step-shaped locking steps are formed by cone portions that are arranged at appropriate intervals on a vertical column and each gradually reduces the shaft diameter of the lower portion. In a locking pawl device for a hydraulic jack for lifting and lowering that externally inserts a pair of movable cylindrical members and moves both movable cylindrical members alternately, the pawls are arranged coaxially at the locking stage of the guide rod at equal intervals, and are parallel to each other. A plurality of engaging elements each having a sloped top surface and a sloped bottom surface with a downward slope in the outward radial direction, and a sloped surface abutting the cone part at the inner end, and further having a horizontal bottom surface at the inner end corner of each of the sloped bottom surfaces. a plurality of inclined guides each having a center hole that is externally inserted into the fixed guide rod, extending downwardly in the outward radial direction at equal intervals in the center hole, and each having the above-mentioned engagement block slidably built therein; A vertically movable cylindrical member having a hole, and an engagement built in the vertically movable cylindrical member that moves each of the above-mentioned engagement blocks simultaneously in an inward radial direction and an outward radial direction along the inclined guide hole by supplying and discharging pressurized oil. A locking pawl device for a lifting hydraulic jack, characterized by comprising a block moving member.