JPH0791028B2 - Locking pawl device for lifting hydraulic jack - Google Patents

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 lifting hydraulic jack.

[0002]

2. Description of the Related Art As a hydraulic jack for lifting heavy objects,
Conventionally, for example, as shown in the vertical sectional view of FIG.
It is known that it was announced in No. 45858. That is, in the same drawing, the jack extends vertically and has a fixed vertical guide rod 02 in which a plurality of locking steps 01 are formed in a multi-step manner at appropriate intervals, and an inner cylinder 03 coaxially externally inserted in the central portion thereof. A central cylinder 07 composed of a cylindrical piston 06 that is inserted between the outer cylinder 04 and the outer cylinder 04 that can move in the vertical direction, and is connected slightly above this with a plurality of bolts 08. In addition, the guide rod 02 is mainly formed of an upper cylinder 09 through which the central hole is inserted, 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 is inserted through the central hole. Where 011 and 012
Are the upper and lower oil supply and drain ports of the central cylinder 07, 013 and 014 are the upper cylinder 0, respectively.
9. A frustoconical spring chamber formed in the lower part of the lower cylinder 010, and 015, 016 are springs 0 above them.
A frusto-conical locking claw with a central hole into which the guide rod 02 is inserted through the center, which are pressed against each other via 17, 018 and the bottom plates 019, 020, and 021 and 022 are upper portions of the upper cylinder 09 and the lower cylinder 010, respectively. It is a hollow piston rod that is inserted into the pressurizing chamber 023,024 formed in the center and has a piston projecting in the center, and the guide rod 02 is inserted through its center hole, and the lower ends are the upper ends of the locking claws 015,016, respectively. Is in contact with. Reference numerals 029 and 030 denote upper and lower oil supply / drain openings, 031 and 032, respectively, of the pressurizing chamber 023.
The upper and lower oil supply / drain ports of the pressurizing chamber 024 are respectively, and 033 is the lower end flange 034 of the central cylinder 07.
It is the load that is suspended via the suspension 035.

However, in such an apparatus, however, the locking claws 015 or 0 which are fitted to the guide rod 02 to move up and down.
To remove 16, hollow piston rod 021 or 022
Since it is necessary to drive the locking claw 015 or 016 away from the locking position, it takes extra time for this, and there is a drawback that the lifting speed of the jack becomes slower.

Therefore, the applicant of the present invention has previously filed Japanese Patent Application No. 2-4.
11478 proposed the "hydraulic jack for lifting".
That is, as shown in the vertical cross-sectional view of FIG. 8, the upper guide cylinder 038, the middle cylinder 039 and the lower lock cylinder 040 are connected to the vertical guide rod 037 in which the notches 036 are recessed in multiple stages in the axial direction at appropriate intervals. In a hydraulic jack for raising and lowering, in which an elevator is coaxially inserted, an upper half cylinder 041 and a lower half cylinder 04 are attached.
Central cylinder 03, which is vertically symmetrically connected to 2
9, upper half cylinder 041 and lower half cylinder 04
2, a connecting pipe 043 connecting the upper ends of the two to each other, an upper locking cylinder 038 connected to the hollow piston 044 of the upper half cylinder 041, and a lower half cylinder 04.
The lower lock cylinder 040 connected to the two hollow pistons 045, the upper lock cylinder 038, and the lower lock cylinder 040, which are respectively arranged in the upper and lower hollow cylinders 046 and 047, are diagonally moved up and down to form a notch 036 at the inner lower corner. It is provided with a locking claw 048 that fits in and out of the. However, in such a device, the locking claw 048 is notched 0 in the guide rod 037 under a load.
There is a fear of falling out of 36.

[0005]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above circumstances, and has a short fitting / removing time and reliable fitting / removing, and therefore has an ascending / descending hydraulic pressure excellent in lifting speed and safety. An object is to provide a locking claw device for a jack.

[0006]

To this end, the present invention provides a fixed guide in which a plurality of annular step-like locking steps are formed by cone portions which are arranged at appropriate intervals on a vertical column and which gradually reduce the shaft diameter of the lower portion. In a locking claw device for a lifting hydraulic jack in which a pair of upper and lower movable cylindrical members each having a built-in fitting / removing block are externally inserted into a rod and the movable cylindrical members are alternately moved, coaxially with a locking step of the guide rod. Each of them has an inclined top surface and an inclined bottom surface which are arranged at equal intervals and are parallel to each other and which are inclined downward in the outward radial direction, and also have an inclined surface which abuts on the cone portion at the inner end, and further the inner end of each of the inclined bottom surfaces. A plurality of engaging blocks each having a horizontal bottom surface at a corner portion, and a central hole that is inserted into the fixed guide rod, and extend at a downward gradient in an outward radial direction at equal intervals in the central hole. A vertically movable cylindrical member having a plurality of sloping guide holes that are movably incorporated therein, and the engagement blocks that are incorporated in the vertically movable cylindrical member and are inclined inward and outward in a radial direction all at once by supplying and discharging pressure oil. And an engaging block moving member that moves along the guide hole.

[0007]

When the locking claw is fitted on the guide rod, if the load acting on the guide rod is F, the locking claw block is Fco.
Press the guide rod with the force of sQ ₂ · sinQ ₂ . Also, the push-up force of the compression spring acting on the locking claw block is set to P ₁
Then, the locking claw block is P ₁ cosQ ₃ · sinQ
Press the guide rod with the force of ₃ . Furthermore, when releasing the locking claw block from the guide rod, if a pressing force P ₂ is applied to the removal cam by hydraulic pressure, the locking claw block will be P ₂ cosQ.
The force of ₃ · sinQ ₃ pulls it away from the guide rod, but at this time, this force is designed to be smaller than the force FcosQ ₂ · sinQ ₂ above. . Then, when the locking claw block is detached from the guide rod, the lifting minimum movement amount of the locking claw block is small because of its shape.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. The same reference numerals as those in FIG. 7 denote the same members as in the same drawing. First, in the longitudinal sectional view of FIG. Is a locking claw block group in which the fan-shaped locking claw blocks 2 are arranged in a substantially annular shape in cooperation with each other. By sliding in the inclined guide hole, the engaging step 01 of the guide rod 02 can be fitted into and disengaged from. Reference numeral 4 denotes a hollow piston inserted into the upper end of a compression spring 5 elastically mounted in the center hole of the bottom of the apparatus body 3, and 6 denotes a plurality of lower ends fixed to the shoulders of the upper end of the hollow piston 4 at equal intervals. Adjacent columns 6, 6
Between both upper ends, arcuate pressing plates 7 each having an arcuate shape and slidable on the conical outer peripheral surface of the locking claw block 2 are supported at both ends with an outward radial gradient. Reference numeral 8 denotes a detachment cam fixed to the locking claw block 2 via a plurality of stud bolts 9 penetrating through the long hole, and 10 denotes a supply / discharge oil port for supplying / discharging pressure oil to / from the outer peripheral surface of the hollow piston 4. Next, in the partially enlarged view of FIG. 2 and the plan view of FIG. 3, 11 is a locking step 0 of the guide rod 02.
1 is a horizontal bottom surface of a locking claw block 2 that abuts 1. Thirteen
Is the inner peripheral surface of the locking claw block 2 that abuts the cone guide portion 035a of the guide rod 02, which has a steep upward gradient in the outward radial direction. Reference numeral 15 denotes an inclined top surface of the locking claw block 2 which receives a load from the apparatus main body 3, which has a downward slope in the outward radial direction. Reference numeral 16 denotes an inclined bottom surface continuous with the horizontal bottom surface 11 of the locking claw block 2, which is parallel to the inclined top surface 15. Reference numeral 17 denotes an outer peripheral surface of the locking claw block 2 forming a sliding contact surface with the push plate 7, which has an upward gradient in the outward radial direction.

In such a device, the locking claw block 2 and the disengagement cam 8 are integrally assembled by a stud bolt 9 with an appropriate clearance, and two columns 6 adjacent to this clearance are loosely slid. It is inserted so that it can be freely contacted, and the fitting of the guide rod 02 of the locking claw block 2 to the locking step 01 is
As shown in the right half of FIG. 1, the push plate 7 pushes up the locking claw block 2 through the hollow piston 4 pushed up by the compression spring 5 and the column 6. Further, as shown in the left half of FIG. 1 and a partially enlarged view of FIG. 4, the guide rod 02 of the locking claw block 2 is disengaged from the main body 3 of the device slightly by an elevating means (not shown). Figure 5a)
After ascending, pressure oil is supplied from the oil supply / discharge 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 through the support column 6, the 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. 5, and when the load F acts on the inclined top surface 15 during fitting, the locking claw block 2 becomes F.
Since the guide rod is pressed by the force of cosQ ₂ · sinQ ₂ , the disengagement of the locking claw block 2 must occur with this force or more. Therefore, the output of the disengagement device calculates the minimum value of the load F as the own weight of the jack. The pressing force can be suppressed to less than the above-mentioned pressing force, and the pushing force P ₁ of the compression spring 5 to the outer peripheral surface 17 of the locking claw block 2 causes the locking claw block 2 to move to P ₁ cosQ ₃
・ Press the guide rod with the force of sinQ ₃ . Further, when the pressing force P ₂ is applied to the separation cam 8 by the hydraulic pressure during separation,
The disengagement cam 8 tries to disengage the locking claw block 2 outward in the radial direction by the force of P ₂ cosQ ₃ · sinQ ₃ .
Since this force is designed to be smaller than the above force FcosQ ₂ · sinQ _2, even if a disengagement signal is mistakenly applied during the fitting, the locked state is maintained, and the locking claw block 2 is locked by the locking step 0.
It never leaves 1. In order to remove the locking claw block 2, the load F is first received by the lower locking claw block (FIG. 6), and then the apparatus main body 3 is lifted by a, and the guide rod by the upper locking claw block 2 is lifted. Pressing force FcosQ ₂・
Since sinQ ₂ becomes zero, the upper locking claw block 2
Can be disengaged only by its own weight, and the minimum lifting amount a at that time is a dimension determined by the angle Q ₂ . In addition,
FIG. 6 is a vertical cross-sectional view showing an elevating device formed by coaxially mounting the locking claw devices connected to the upper and lower ends of the hydraulic jack 18 to the guide rod 02, and 19 is an elevating floor.

According to the apparatus of this embodiment, a plurality of fan-shaped locking claw blocks which are arranged coaxially and are capable of contacting with the locking step of the guide rod, and the above-mentioned engaging member. An inclined top surface and an inclined bottom surface that form a part of the claw block and are parallel to each other and are downwardly inclined in the outward radial direction; horizontal bottom surfaces formed at the inner peripheral side ends of the respective inclined bottom surfaces; Since a plurality of columns having a mechanism for sliding the claw blocks in the radial direction are provided and a compression spring on which a hollow piston that supports the columns is mounted, the following effects can be obtained. (1) If the load acting on the guide rod is the FcosQ when the locking claw is fitted, the locking claw block is FcosQ.
_The guide rod is pressed by the force of ₂ · sinQ ₂ , so the fitting is highly reliable and the safety is improved. (2) Further, when the locking pawl block is fitted to the guide rod and the push-up force of the compression spring acting on it and P _1, the locking claw block guide with a force of P ₁ cosQ ₃ · sinQ ₃ The rod is pressed, and thus the certainty of fitting is further increased, and the safety is improved. (3) When the locking claw block is disengaged from the guide rod, the load F is applied after receiving the load F by the locking claws of the other lifting hydraulic jacks, thus improving safety. (4) When releasing the locking claw block from the guide rod, if a pressing force P ₂ is applied to the release cam by hydraulic pressure, the locking claw block will be separated from the guide rod by the force of P ₂ cosQ ₃ · sinQ _3. However, at this time, this force is the above force Fco.
It is designed to be smaller than sQ ₂ · sinQ ₂ , so that even if there is an erroneous signal during mating, disengagement does not occur, so safety is improved. (5) Further, when the locking claw block is detached from the guide rod, the minimum lifting amount of the locking claw block is small because of its shape, and therefore the lifting speed is improved. (6) According to the device of FIG. 6 in which the locking claw device of the present embodiment is applied to the lifting hydraulic jack previously proposed by the applicant, the lifting motion is continuous and the safety is improved. The use of the device expands.

[0011]

In summary, according to the present invention, a fixed guide rod having a plurality of annular step-shaped locking steps formed by cone portions arranged at appropriate intervals on a vertical column and gradually reducing the shaft diameter of the lower portion is fitted. In a retaining pawl device for a lifting hydraulic jack in which a pair of upper and lower movable cylindrical members having built-in deblocking blocks are externally inserted, and the movable cylindrical members are alternately moved, coaxially equidistantly with the retaining steps of the guide rod. Each of them has an inclined top surface and an inclined bottom surface that are parallel to each other and have a downward slope in the outward radial direction, and an inclined surface that abuts the cone portion at the inner end, and further at an inner end corner portion of each inclined bottom surface. It has a plurality of engaging blocks having a horizontal bottom surface, and a central hole to be inserted into the fixed guide rod, and extends outwardly in a downward gradient in the outward radial direction at equal intervals in the central hole, and the engaging blocks are slidable inside respectively. To A vertically movable cylindrical member having a plurality of inclined guide holes to be housed therein, and the engaging blocks that are built in the vertically movable cylindrical member and supplied and discharged with pressure oil, are collectively inwardly and outwardly radially directed to the inclined guide holes. Since the engaging block moving member that moves along is provided, the engaging and disengaging time is short, and the engaging and disengaging is reliable, and therefore, the locking claw device for the lifting hydraulic jack having excellent lifting speed and safety is obtained. The present invention is extremely useful in industry.

[Brief description of drawings]

FIG. 1 is a vertical 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.

FIG. 3 is a partial plan view of FIG.

FIG. 4 is a partially enlarged view showing a disengaged state of the locking claw block of FIG. 1.

5 is a partial enlarged view for explaining the mechanical relationship of the forces acting on the locking claw block of FIG. 1. FIG.

FIG. 6 is a vertical sectional view showing an elevating device to which the locking claw device of the present invention is applied.

FIG. 7 is a vertical sectional view showing a known lifting hydraulic jack.

FIG. 8 is a vertical cross-sectional view showing a “hydraulic jack for lifting and lowering” proposed by the present applicant.

[Explanation of symbols]

1 Locking Claw Block Group 2 Locking Claw Block 3 Device Main Body 4 Hollow Piston 5 Compression Spring 6 Strut 7 Push Plate 8 Detaching Cam 9 Bolt 10 Oil Supply / Discharge Port 11 Horizontal Bottom 13 Inner Circumferential Surface 15 Slope Top 16 Slope Bottom 17 Outer peripheral surface 18 Hydraulic jack 19 Lifting floor 01 Locking step 02 Guide rod 035a Cone guide part a Minimum moving amount F Load P ₁ Pushing force P ₂ Pushing force Q ₁ angle Q ₂ angle Q ₃ angle

Claims (1)

[Claims] 1. A fixed guide rod having a plurality of annular step-shaped locking steps formed by cone portions which are arranged at appropriate intervals on a vertical column and which gradually reduce the shaft diameter of the lower portion. In a locking pawl device for a lifting hydraulic jack in which a pair of movable cylindrical members are externally inserted, and the movable cylindrical members are alternately moved, the locking claw devices are coaxially arranged at the locking steps of the guide rod and are parallel to each other. A plurality of members having an inclined top surface and an inclined bottom surface that are downwardly inclined in the outward radial direction, an inclined surface that abuts the cone portion at the inner end, and a horizontal bottom surface at the inner end corner of each inclined bottom surface. A plurality of slant guides each having a coupling block and a central hole externally inserted into the fixed guide rod, and extending in a downward gradient in an outward radial direction at equal intervals in the central hole and slidably incorporating the engaging blocks therein. Hole A vertically movable cylindrical member, and an engagement block which is built in the vertically movable cylindrical member and moves the engaging blocks at the same time in the inward radial direction and the outward radial direction along the inclined guide hole by supplying and discharging pressure oil. A locking claw device for a lifting hydraulic jack, comprising a moving member.