GB2350862A

GB2350862A - Locking device for a collapsible container hinge

Info

Publication number: GB2350862A
Application number: GB9919259A
Authority: GB
Inventors: Linda B Ma
Original assignee: Polyearn Development Corp
Current assignee: Polyearn Development Corp
Priority date: 1999-06-08
Filing date: 1999-08-13
Publication date: 2000-12-13
Anticipated expiration: 2019-08-13
Also published as: CN1252378A; GB9919259D0; GB2350862B; CN1121337C

Abstract

A hinge means for a foldable container, comprising an inner hinge plate (18) and two outer hinge plates (19) spaced apart and parallel to each other, said inner hinge plate being pivotally connected to said outer hinge plates via a pivotal shaft (20) perpendicular to the hinge plates; characterised in that, said hinge means further comprises a lock pin (23) in the shape of a flat topped pyramid with a rectangular cross-section, being slideable along the direction of an end beam (3), said inner and outer hinge plates having complementary shaped locking holes (24) made thereon, though which said locking pin can be inserted; a slide hammer (28) rigidly connected with a U-shaped handle (27) is further included to drive the lock pin in or out of the lock hole. A locking board (26) pivotally connected to the end beam may also be included to restrict movement of the slide hammer.

Description

2350862 HINGE MEANS FOR A FOLDABLE CONTAINER The present invention relates

to the structure of shipping containers, and more particularly to a hinge construction which pivotally connects the corner post and the platform base of a special container called foldable container.

Typically, a foldable container comprises a platform base and four vertical corner posts. The posts are located respectively at four corners of the platform base, and pivotally connected with the platform base by hinge means. The two corner posts at each end are generally joined by an end wall. Each of the corner posts can be locked to the erect position with the locking device of the hinge means, and can be folded down to the platform base when unlocking. When every post is folded down to the base, the foldable container can be used as an ordinary platform container, while other folded containers can be stacked upon to enable economical storage and transportation.

When goods are loaded onto a foldable container for transportation, the corner posts of the container are locked at the erect position, and usually other similar containers are piled up on the tbp of the corner post. At this time, large forces are applied onto the top of the corner posts, and whereby, the forces are also applied to the locking device of the hinge means through the corner posts. It not only requires that the corner posts and their locking devices be firm and strong enough, but it also requires that no clearance exists in the locking device after locking to prevent the corner posts from swaying, so as to ensure 0 W easy piling up of other containers on the top of the corner posts and stability of the stacked containers.

Normally, the locking device of the hinge means employs cuboidal, cylindrical, ellipsoidal, wedge shaped or conical lock pins, and has corresponding lock holes on the hinge plates to realize locking. When cuboidal or cylindrical lock pin is used, the clearance always exists between the lock pin and the holes. When wedge shaped lock pin is used, as disclosed in US patent No. 4353520, it is difficult for its two sides vertical to the hinge plates to enter the lock holes. Otherwise, large clearance may exist, like in the case of cuboidal lock pins. When ellipsoid is used as the lock pin, locking is realized by bias force generated during relative rotation between the lock pin and the lock hole, but large portion of the lock pin and the lock hole can not get into contact. When conical lock pin is used, as disclosed in GB2073149, no clearance exists between the lock pin and the lock hole after locking, but when left-right forces applied on the corner posts alternately, the corner posts are likely to rotate around the axis of the lock pins, and whereby, affecting the stability of the corner posts.

The locking device of common hinge means further comprises a guiding axle integrated with the lock pin, and a slide hammer and check plates are mounted on the 1 guiding axle. By impacting a check plate with the slide hammer, an impact force generated will be applied to the lock pin and push it entering the corresponding lock hole, and whereby, the corner posts are locked. To make the corner posts folded, simply impact another check plate in the reverse direction, and whereby, the lock pin is drawn out of the lock hole. The slide hammer of common locking device is in the shape of a dumbbell, big at both ends and small in the middle. In operation, one has to grasp the dumbbell shaped slide hammer with hand directly. Sometimes, if one impact with the slide hammer abruptly, he will likely be hurt on his hand by the collision of the dumbbell end with the check plate on the guiding axle. Therefore, the dumbbell shaped slide hammer is not satisfactory in safety. Another kind of slide hammer is provided with a straight handle vertically connected therewith, as disclosed in US patent No. 435320. Although this kind of slide hammer is improved in safety, it is not convenient to exert forces along the guiding axle and it is therefore not easy to drive the lock pin to go forward or backward by impact on the check plate mounted on the guiding axle. Due to the difficulty to make the accurate operation angle, the axis of the slide hanuner is likely biased with the axis of the guiding axle, and whereby, the slide hammer is obstructed on the guiding axle. Subsequently, the normal operation is affected.

The primary objective of the present invention is to provide a hinge means for foldable containers, which can significantly eliminate the clearance between the lock pin and the lock holes after locking, increase as more as possible the contact surface of the lock pin with the lock holes, and prevent the axial rotation of the lock pin, so as to prevent the corner posts from swaying, ensure the easy piling up of other containers on the top of the corner posts, and the stability of the stacked containers.

Another objective of the present invention is to overcome the disadvantages possessed by the prior art slide hammer in the locking device of the hinge means, and to provide a slide hammer which is convenient, safe and effective to use in the locking device.

In accordance with the invention, there is provided a hinge means, comprising an inner hinge plate and two outer hinge plates spaced apart and parallel with each other, said inner hinge plate being located between and in parallel to the two outer hinge plates, the end of said inner hinge plate being ridgidly connected with the comer posts; said inner hinge plate is pivotally connected with said outer hinge plates via a pivotal shaft vertical to the hinge plates; said outer hinge plates are parallel with the side beam of the platform base and ridgidly connected with the side beam and end beam of the platform base; said hinge means further comprises locking device by which the corner posts are locked at the erect position; said locking device includes a lock pin slideable along the direction of said end beam, and corresponding lock holes vertically made on said outer and inner hinge plates; said lock pin is ridgidly connected at one end of the guiding axle, and the other end of the guiding axle passes through the hole on a upright plate; said upright plate is 2 ridgidly connected with and vertical to said end beam, on said guiding axle are two check 0 plates which are both vertical to and ridgidly connected with said guiding axle, and between the two check plates is a slide hammer which has an inner hole enveloping outside the guiding axle and can be slid along said guiding axle; characterized in that, said lock pin is in the shape of a flat topped pyramid with rectangular cross-section, said lock holes are correspondingly in the shape of flat topped pyramids; and said slide hammer has a U-shaped handle ridgidly connected therewith for safe and convenient operation.

In above mentioned hinge means, since the lock pin of the locking device is shaped to a flat topped pyramid, and the corresponding lock holes in the inner and outer hinge plates are also in the shape of flat topped pyramids, the locking and unlocking can be realized by the axial movement of the lock pin within the lock holes. In locking, the surface of the lock pin is in completely contact with the surface of the lock holes, which gives rise to a large locking force to bear large load. Thanks to the flat topped pyramidal lock pin and the corresponding lock holes, there will be no trend of rotation for the lock pin inserted in the lock holes, As long as the lock pin has not yet been driven out of the lock hole, the corner post is in a stable state, with no risk of falling down, and whereby, the stability and safety of the corner post is significantly increased compared with using lock pins of other shapes. In present invention, a U-shaped handle is provided on the slide hammer, and whereby, it is very convenient to use the slide hammer with the U-shaped handle. No matter how strong is the force exerted, one will not get hurt on his hand by the collision of the hammer with the check plates. With the U- shaped handle, it is convenient to operate the slide hammer to exert force along the axial direction of the guiding axle, and to effectively impact on the check plates amounted on the guiding axle Q to drive the lock pin move foreward or backward. Such that, the occasional obstruction of the slide hammer on the guiding axle can be completely avoided, and it is very convenient to exert force and to operate the slide hammer.

Detailed description of the present invention will be given below by way of examples with reference to the accompanying drawings.

Figure I is a perspective view of a foldable container; Figure 2 is a side view of several folded containers piled up one by another; Figure 3 is a perspective view from bottom corner of the foldable container in locking state; Figure 4 is a sectional view of the inner and outer hinge plates, and the flat topped pyramidal lock holes thereof; Figure 5 is a perspective view from bottom corner of the foldable container in unlocking state.

Fig. I shows a typical foldable container, which comprises platform base 1, end beam 3, basal side beam 4, corner post 5, end wall 6, end top beam 7 and end bottom beam 8. Corner fittings 9, 10 are fixed to each corner of the folding container, and a hole 3 11 is made in each corner fitting 9 for handling tools or twist locks. The end wall 6 can be locked at the erect position with the locking device of the hinge means 12 as shown in the figure, and can be folded down to the base I when the locking device of the hinge means 12 is unlocked.

Fig. 2 shows a group of similar folded containers 13, 14, 15, 16,17 piled up one on another for the convenience of transportation and storage.

Fig. 3 is a perspective view from bottom corner of the foldable container in locking state, where its locking device is a preferred embodiment of the present invention. The locking device comprises an inner hinge plate 18 and two outer hinge plates 19 spaced apart and parallel with each other. The inner hinge plate 18 is located between and in parallel to the two outer hinge plates 19. The end of the inner hinge plate 18 is ridgidly connected with the corner post 5. The inner hinge plate 18 is pivotally connected with the outer hinge plates 19 via a pivotal shaft 20 vertical to the hinge plates. The outer hinge plates 19 are parallel with the side beam 4 of the platform base 1 and ridgidly connected with the side beam 4 and end beam 3 of the platform base 1. The hinge means further comprising a lock pin 23 in the shape of a flat topped pyramid with rectangular crosssection, being slideable along the direction of the end beam 3. And the inner and outer hinge plates 18, 19 have corresponding flat topped pyramidal holes 24 vertically made thereon, through which the lock pin 23 can be inserted into the hinge plates 18, 19.

The inner hinge plate 18 can be rotated around the pivotal shaft 20, such that the corner post 5 can be either erected or folded down to the horizontal plane along the side beam 4. The flat topped pyramidal lock pin 23 is inserted into the lock hole 24 to lock the corner post 5 at the vertical position when it is erected.

Referring to Fig. 3, in this embodiment, the flat topped pyramidal lock pin 23 is ridgidly connected at one end of the guiding axle 30, while the other end of the guiding C ID axle '30 passes through the hole 32 on the upright plate 31 which is vertical to and ridgidly connected with the end beam 3. On the guiding axle 30 are check plates 25 and 29 which are vertical to and ridgidly connected with the guiding axle 30, and between the check plates 25 and 29 is a slide hammer 28 which has an inner hole enveloping outside the guiding axle 30 and can be slid along the guiding axle 30. The slide hammer 28 has a U-shaped handle 27 ridgidly connected therewith. In the present embodiment, the slide hammer 28 is in the shape of a cylinder having an inner hole along its center axis. A blocking board 26 moveably connected with the end beam 3 via the pivotal axle 33 is also provided at an appropriate position relative to the guiding axle 30.

With the U-shaped handle 27, the slide hammer 28 can be made to impact on the check plates 25 or 29 amounted on the guiding axle 30, and whereby, the lock pin 23 is axially shifted in the lock hole 24, so as to realize locking or unlocking.

Being limited by the check plate 29 and the upright plate 3 1, the lock pin 23 can be only axially shifted in the lock hole 24, even when the locking device is unlocking, the 4 lock pin 23 is drawn at a position neither affects the folding of the inner hinge plate 18 nor falls out of the outer hinge plates 19.

In Fig. 3, the comer post 5 is at the erect position, and the locking device is in locking state. The locking process is as follows: when the corner post 5 is at the erect position, first lift up the blocking board 26, and rotate it around the rotation axle 33, then, hold the U-shaped handle 27 of the slide harnmer 28 to impose an external force to drive the slide hammer 28 forward to impact the check plate 25 along the guiding axle 30. As a result, the lock pin 23 and all the other parts fixed on the guiding axle 30 are moved forward along with the guiding axle '30. Under the horizontal handling force forward generated by the slide hammer 28, the lock pin 23 is gradually inserted into the lock hole 24 on the inner and outer hinge plates. The surface of the lock pin 23 is made to be completely in contact with the lock hole 24, so as to realize locking of the inner hinge plate 18 and the comer post 5 with the outer hinge plates 19. At the same time, lower down the blocking board 26 to block at one side 34 of the check plate 25. The lower end of the blocking board 26 is arc shaped similar to that of the guiding axle 30. The coupling of the blocking board 26 with the check plate 25 makes a restriction to the arbitrary movement of all the parts fixed on the guiding axle 30, including the lock pin 23.

Fig. 4 is sectional view of the flat topped pyramidal lock holes on the inner and outer hinge plates, which illustrates the relationship of the lock pin 23 with the lock hole 24 on the inner and outer hinge plates during locking of the locking device. At the beginning, when the lock pin 23 is inserted inward, only a little portion of the surface of the lock pin 23 gets in contact with the lock hole on the inner and outer hinge plates. When the lock pin 23 is further inserted inward, the contact surface of the lock pin 23 with the lock hole 24 is increased gradually, the further the lock pin 23 is inserted, the tighter the lock pin 23 and the lock hole 24 on the inner and outer hinge plates are in contact, until finally secured locking, is achieved.

Figure 5 is a perspective view from bottom corner of the foldable container in unlocking state. When the locking device is to be unlocked from locking state, first lift up the locking board 26 to rotate it around the rotation axle 33. Then, hold the U-shaped handle 27 on the slide harnmer 28 to impose an external force to drive the slide harnmer 28 backward to impact the check plate 29 along the guiding axle 30. As a result, the lock pin 23 and all the other parts fixed on the guiding axle 30 are moved backward along with the guiding axle 30. Under the horizontal handling force generated by the slide hammer 28, the close contact of the lock pin 23 with the lock hole 24 on the inner and outer hinge plates is gradually released, until finally, the lock pin 23 comes out of the lock hole 24. When the check plate 29 touches the upright plate 31, the lock pin 23 is drawn to the position not affecting the rotation of the inner hinge plate 18 and the corner post 5. At this time, lower down the blocking board 26, then fold the corner post 5 down to the platform base around the pivotal shaft 20.

The advantages of the present invention are as follows: in locking, the surface of the lock pin 23 is almost in complete contact with the surface of the lock hole 24, and whereby, a large locking force is generated which can bear large load. After locking, the locking device posses the feature of self-locking. In addition, the lock pin 23 and the lock hole 24 are stably locked even when they are worn out, i.e., the locking device has compensation property. Finally, since the lock pin 23 is in the shape of a flat topped pyramid, instead of cylinder, conoid or ellipsoid, the lock pin will not rotate when forces applied to the corner post after locking.

z The slide hammer 28 employed in the preferred embodiment of the present invnetion is also advantageous over the prior art hammer, and presents safety, convenience and effectiveness in operation.

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Claims

Claims:

1. A hinge means for a foldable container, comprising an inner hinge plate and two outer hinge plates spaced apart and parallel with each other, said inner hinge plate being located between and in parallel to the two outer hinge plates, the end of said inner hinge plate being ridgidly connected with the corner posts; said inner hinge plate is pivotally connected \vith said outer hinge plates via a pivotal shaft vertical to the hinge plates; said outer hinge plates are parallel with the side beam of the platform base and ridgidly connected witli the side beam and end beam of the platform base; said hinge nicans further comprises a locking device by, which the corner posts are locked at the erect position; said locking device includes a lock pin slideable along the direction of said end beam, and corresponding lock holes vertically made on said outer and inner hinge plates; said lock pin is ridgidly connected at one end of the guiding axle, and the other end of the Z 1 C> guiding axle passes through the hole on a upright plate; said upright plate is ridaidly 1 Z> 0 l> connected with and vertical to said end beam; on said guiding axle are two check plates 1 1 which are both vertical to and ridgidly connected with said guiding axle, and between the two check plates is a slide hammer which has an inner hole enveloping outside the 1 guiding axle and can be slid along said guiding axle; characterized in that, said lock pin is 1 0 C - W in the shape of, a flat topped pyramid with rectangular cross-section, said lock holes are 1 correspondingly in the shape of flat topped pyramids; and said slide hammer has a Ushaped handle ridgidly connected thereiih for safe and convenient operation.

2. The invention as defined in claim I, characterized in that, said slide hammer is in the shape of a cylinder having an inner hole along its center axis.

3. The invention as defined in claim 1, characterized in that, a blocking board moveably connected with the end beam via a pivotal axle is further provided at an appropriate position relative to the guiding axle.

4. A hinge means for a foldable container substantially as hereinbefore described with reference to Figures 1 to 5 of the accompanying drawings.

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