Lockable transportation rack for storing and shipping sheet materials

Abstract

A “harp rack” for the storage and shipping of sheet material modified so that the stringers are rotatably mounted for simultaneous rotation relative to a supporting base and frame between a locking position and a release position, the stringers each have locking vanes disposed on opposite sides which terminate in a glass engaging stopper such as rubber.

Description

FIELD OF INVENTION

This invention relates to racks for packaging, storing and transporting sheet material, particularly glass, but also metal, plastic, marble plates, windows and doors.

BACKGROUND OF THE INVENTION

Glass panes are usually produced, cut to specific sizes required by the end user and shipped as lites in pallets which may be boxed in wooden cases. Glass lites are also moved around on factory floors using wheeled pallets known as “harp racks” which consist of steel rods covered with plastic sleeves, mounted to a frame and usually inclined at an angle of approximately 50° to separate glass panes supported on a slotted base. The harp racks are available in many configurations and can have one or two levels or decks disposed one above the other, optionally with an inner string set of shorter rods to accommodate and separate glass panes having smaller dimensions and an outer string set of longer rods to accommodate and separate larger glass panes. While the harp racks may be used for transportation off-site by using plastic shrink-wrap to immobilize the glass lites on the racks, this is not a satisfactory solution and harp racks are not generally considered suitable for shipping glass lites to another location.

An object of this invention is to provide means for securing sheet material in a harp style rack so that the same rack may be used for moving the sheet material at the pick-up and delivery locations without any intermediate loading and unloading for shipping between locations and without the need for plastic shrink wrap or other securing devices.

SUMMARY OF THE INVENTION

In accordance with this invention, there is provided a so-called “harp rack” in which the stringer assembly is modified so that the stringers are rotably mounted for simultaneous rotation relative to a supporting base and frame between a locking position and a release position, the stringers each having transversely extending locking means disposed on opposite sides and terminating in a glass engaging stopper such as rubber.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the invention may be more clearly understood, a preferred embodiment is described below with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a double level, double string locking harp rack made in accordance with the invention;

FIG. 2 is a top plan view of a glass pane trapped between a pair of stringers rotated into a locking position;

FIG. 3 is a top plan view similar to FIG. 2 showing the stringers rotated into a release position;

FIG. 4 is an exploded view showing a stringer assembly and a frame for the locking harp rack;

FIG. 5 is a perspective view showing the stringer assembly of FIG. 4 in an assembled configuration; and

FIG. 6 (drawn to a larger scale) is a side elevation of a portion of the stringer assembly of FIG. 5.

DESCRIPTION OF PREFERRED EMBODIMENT WITH REFERENCE TO DRAWINGS

A locking harp rack made in accordance with the invention is generally indicated by reference numeral 20 in FIG. 1. Like prior art harp racks, the harp rack 20 has a base 22 which has a series of spaced parallel grooves 24 that extend along the length of the base 22 to support sheets of glass and the like (not shown). The base 22 is conveniently made of synthetic plastic material such as high density polyethylene which can be cut to form the grooves 24. The base 22 is supported in a frame 26 on locking caster wheels 28. An upper deck 30 similar to the base 22 is vertically disposed above the base 22 to accommodate a second tier of sheets or glass panes.

A plurality of stringers 32 are mounted to the frame 26 and are spaced from each other along the width of the base 22 between each of the grooves 24 to form a lower string set 34 inclined at about 50° between the base and a horizontally extending mounting channel 38 forming part of the frame 26. An upper string set 36 is inclined at a similar angle between the upper deck 30 and a respective horizontally extending support 40. In the embodiment illustrated, the base 22 and the upper deck 30 each support an inner string set 42, 44 to accommodate sheets or glass panes having smaller dimensions. The inner string sets 42, 44 are conventional in nature and consist of metal rods fixed to the frame and covered with a synthetic plastic sleeve.

The stringers 32 in the lower string set 34 have been modified in accordance with this invention to be rotatable relative to the horizontally extending support 38 and the base 22 between a locking position and a release position using an operator handle 46.

The construction of the stringers 32 will now be described with particular reference being made to FIGS. 2, 3 and 6. Each stringer 32 has a pair of metal rod terminations 48 fitted and welded to a longitudinally extending central metal plate 50. The metal plates 50 have a narrow width of z-shaped cross-section (FIGS. 2, 3) that defines a pair of transversely extending locking vanes disposed on opposite sides of the stringers 32. The free edges of the metal plate 50 are covered by a rubber stopper 52 consisting of a narrow strip of rubber sheet glued to opposite sides of the metal plate so that only soft resilient material will engage a glass sheet 54 received in a groove 24. The lower rod termination 48 is received in a journal-bearing formed in a bottom guide plate 56 (FIG. 4) disposed in the base 22.

Rotation means for rotating the stringers 32 will now be described with reference to FIGS. 4, 5, 6. The upper rod terminations 48 traverse the mounting channel 38 forming part of the frame 26 through a series of respective apertures 39 formed therein and are received in respective journal bearings formed in an upper rod guide 58 fixed to the channel 38. The upper rod terminations 48 each have a respective spring arm 60 extending transversely to the axis of the rod terminations 48 which engages a sliding plate 62.

The sliding plate 62 is slidably mounted in the channel 38 through three sliding guides 64 spaced across the width of the channel 38 and having a groove for slidably receiving the sliding plate 62. Respective pins 66 traverse the sliding guides 64 and are received in corresponding slots 68 formed in the sliding plate 62. The upper edge of the sliding plate (as drawn) is castellated or notched to receive a respective spring arm 60 and a spring biasing coil 70 in each notch whereby contact is maintained between the sliding plate 62 and the spring arm terminations 60.

The external operator handle 46 is pivoted to the frame at pivot pin 72 and carries a connecting rod 74 which is coupled to one end of the sliding plate 62 so that rotation of the handle 46 causes translation of the sliding plate 62, as indicated by arrow 76. It will be noted that the connecting rod 74 is threaded so that its length may be adjusted for tighter or looser locking force. Meanwhile, downward rotation of the operator handle 46 from the release position (as drawn) will cause the handle 46 to traverse the center of rotation of pivot pin 72 and come to rest in an over-centre locking position.

In use, such rotation of the operator handle 46 to pull the sliding plate 62 to the left (as drawn) allows the spring coils 70 to expand and bear against the spring arms 60, thereby rotating the stringers 32 as indicated by arrow 78 in FIG. 2 to cause the stoppers 52 to firmly engage the glass sheet 54 at substantially right angles on opposite sides thereof.

Each glass sheet 54 is thus trapped between a pair of stringers 32 each of which makes line contact with the glass sheet 54 along the length of the stopper 52. Release of the glass sheets as shown in FIG. 3 can only be achieved by positively moving the operator handle 46 upward to bring the handle over the center of rotation of pivot pin 72 and to push the sliding plate 62 against the spring arms 60 so that the spring coils 70 are compressed (as drawn). Pushing against the spring arms 60 causes the stringers 32 to rotate in the opposite direction as shown by arrow 80 in FIG. 3 thereby bringing the stringers to a release position where the stoppers 52 are spaced from the glass sheet 54.

It will be understood that several variations may be made to the above-described embodiment of the invention within the scope of the appended claims, as will be apparent to those skilled in the art. In particular, the shape and configuration of the stringers may be varied to have for example, a plurality of stoppers each making point contact with the sheet and the mechanism for rotation of the stringers may be substituted by others, such as, for example, a rack and pinion means for translating a carriage to rotate the stringers. Other such variations will be apparent to those skilled in the art and will be considered mechanical equivalents to the embodiment described.

Claims

1. In a transportation rack for storing and shipping sheet material, the rack having

a base coupled to a frame, the base having a width and a length,

the frame having at least one horizontally extending support vertically spaced from the base,

a plurality of stringers spaced from each other along the width of the base and extending between the said at least one horizontally extending support and the base, the stringers being adapted to separate sheets material supported by the base,

the improvement in which the stringers are rotatably mounted for rotation relative to the support and the base between a locking position and a release position, the stringers each having a pair of transversely extending locking vanes disposed on opposite sides thereof and terminating in a glass engaging stopper, and rotation means for simultaneously rotating the stringers to bring the stoppers into and out of engagement with any sheet material supported on the base.

2. A transportation rack according to claim 1 in which the stoppers are made of a resilient material.

3. A transportation rack according to claim 2 in which the stoppers are made of synthetic plastic material or rubber.

4. A transportation rack according to claim 1 in which the locking vanes are integrally formed into a Z-configuration symmetrically disposed on a rotation axis for the stringers, the stoppers being mounted to free ends of the vanes so that, in use, the stoppers will engage the sheet material at substantially right angles.

5. A transportation rack according to claim 1 in which the rotation means is disposed in said horizontally extending support and the base has a journal-bearing for rotation support of the stringers.

6. A transportation rack according to claim 1 in which the rotation means is actuated by an external operator handle, the operator handle being pivotable between said release position and said locking position, where it is locked by an over-centre locking lever.

7. A transportation rack according to claim 1 in which the rotation means has an external operator handle for translating a sliding plate that engages the stringers between said release position and said locking position, the stringers each having respective spring arm terminations for engaging the sliding plate, spring biasing means being disposed between the spring arm terminations and the sliding plate to maintain contact between the sliding plate and the spring arm terminations, whereby translation of the sliding plate causes the stringers to rotate.

8. In a transportation rack for storing and shipping sheet material, the rack having

a base coupled to a frame, the base having a width and a length,

the frame having at least one horizontally extending support vertically spaced from the base,

a plurality of stringers spaced from each other along the width of the base and extending between the said at least one horizontally extending support and the base, the stringers being adapted to separate sheets material supported by the base,

the improvement in which the stringers are rotatably mounted for rotation relative to the support and the base between a locking position and a release position, the stringers each having transversely extending locking means terminating in a glass engaging stopper, and rotation means for simultaneously rotating the stringers to bring the stoppers into and out of engagement with any sheet material supported on the base.

9. A transportation rack according to claim 8 in which the stoppers are made of a resilient material.

10. A transportation rack according to claim 8 in which the stoppers are made of synthetic plastic material or rubber.

11. A transportation rack according to claim 8 in which the rotation means is disposed in said horizontally extending support and the base has a journal-bearing for rotational support of the stringers.

12. A transportation rack according to claim 8 in which the rotation means is actuated by an external operator handle, the operator handle being pivotable between said release position and said locking position, where it is locked by an over-centre locking lever.