This application is a divisional application of the patent application entitled "foldable platform apparatus" with application number 92109507.4, filed on 1992, 8/8.
The foldable platform device is used in various occasions; such as schools, restaurants, convention centers, and other public institutions, for which a temporarily upgradable platform is provided. In each of the above applications, a temporary platform is required for ease of use, and is typically comprised of a plurality of single piece platform members. The members may be placed side by side to form an extended deck or may be provided with a plurality of bridges between the decks to form an extended deck. When not in use, the single platform member can be folded to reduce the size of the space and stored with the bridge plate. Such platforms typically have two hinges connecting the platform members to allow folding, and two legs which fold when the platform is folded and remain upright.
An example of such a folding platform is shown in U.S. patent 4949649 to Teres et al, although the patent to Teres shows that such a platform is very successful in providing an effective and useful foldable platform, further improvements are possible. Particularly with respect to platforms that are deployable for storage of an unoccupied collapsible platform deck. The foldable platform requires a locking mechanism to securely hold the platform surface in a certain position to form a stable platform surface and to prevent the platform from being folded accidentally. The center locking mechanism of the Teres patent requires a relatively complex mechanism that is spring-loaded and arranged between the two deck plates of the foldable deck. The invention provides a locking device on both sides of a platform, which is easy to access and has a simple mechanism with low cost.
To date, prior foldable platforms have been unsatisfactory by providing supporting webs between their platform supports that define the plane of the unfolded platform, and by providing the platforms in the area of the unfoldable area, not providing the folding capability of the supports of each platform, and, in addition, providing storage conditions for the webs on the platforms having a single support.
Portable platforms typically have wheel assemblies. The wheels are rotatable about the stand and contact the ground to raise the support legs off the ground and the platform is wheeled. However, the wheel assembly is mounted near the ground, and the handle can be used to rotate the wheel near the ground. The handle is mounted low enough to bend over to see if the support legs are disengaged from the ground during operation. Since the handle is typically mounted below the deck surface, the operator must bend down below the deck surface to move the wheels between the desired positions, thereby providing poor operational access. Thus, a wheel assembly that provides mechanical advantage and provides easy access to the handle in all positions, coupling or uncoupling the gear train is an advantageous arrangement.
While the prior art foldable platforms are height adjustable, they do not provide the ability to adjust the height of one platform panel relative to another, which allows a foldable platform to form a chord riser structure.
Securing the platform board to the support frame facilitates the securing or removal of the boards by requiring the connectors to be inserted through the channels in the platform board. The connector has a separable top member that is removable from the platform so that it is easily lost and may be inserted incorrectly. The connector has a groove in the channel of the platform board for connecting with the connector to lock the platform board.
It can be appreciated that there is a need for a folding platform that is equipped with a removable platform deck. The platform plate is fastened in an improved manner by means of less loose parts. Clearly, there is also a need for a platform assembly that locks or unlocks the platform and wheels in an easily accessible manner. The operation and storage of the platform plates supported between the platforms should be easy and economical to perform on existing racks. The foldable platform should be capable of adjusting the height of one platform plate relative to the other so that a chord riser configuration can be achieved. The present invention addresses these and other problems associated with folding platforms.
The present invention relates to a temporarily raisable and collapsible platform. It has a platform board supported by folding legs, which are folded from a horizontal position of use of the platform board to a position occupying a small space, while the platform boards are substantially facing each other in the folded position.
The present invention allows the platform board to be replaced by connecting or disconnecting the platform board and the frame. The connecting piece extends into the channel in the platform plate and is in friction fit with the hole wall to fix the platform plate. In addition, a deck plate of a deployable deck is connected between the decks in a hook-like manner atop the deck. When the bridge is not used, the hook is rotated out to be positioned below the platform plate, and redundant connecting bridge plates can be hooked.
The connector of the invention also has the function of supporting and connecting the bridge plates, which can form a widened platform surface between the platforms outside the two sides of the platform, or can also support three bridge plates at one corner of the platform. By the above-described support provided with a plurality of connecting members, various plates can be supported between the platforms.
One deck plate on one deck may be raised relative to the other deck plate by inserting a riser under the connector. Various height risers can be inserted into the top of the rack and under the connectors so that one platform plate can be raised relative to the other, thereby forming a chord riser type structure.
The platform is foldable in a use position, in which the platform panels are substantially horizontally disposed, to a storage position, in which the platform panels are substantially in a face-to-face disposition. When the folding platform is used, the platform needs to be kept stable and unchanged, and the folding phenomenon of the platform caused by pressure on the edge of the platform in use needs not to occur. The present invention has a lock linkage extending between the legs below each deck to allow the legs to be separated from each other. The locking link mechanism is easy to approach, and an operator can easily make the locking link mechanism in a locking or loosening position by stepping on the link. The locking linkage functions as a spacer bar between the set of legs. The spacer bars maintain the distance between the legs constant, thus allowing the platform to be adjusted in height without causing folding.
In addition to the locking linkage for holding the platform in the use position, the present invention is provided with folding aids. I.e. a spring-loaded stay which engages the platform at the last moment when the platform is turned from the folded position to the use position, the folding stay acting like a cushioning device which prevents the platform from suddenly assuming a fully open position due to its own weight, thus preventing crushing injury of the hands or fingers in the folded member of the platform. The springs of the folding struts should have a constant force on the folding legs of the platform to assist in bringing the platform into the storage position when the folding is initiated.
The present invention also provides roller assemblies that allow the platform to be easily transported from a storage location to a use location. The roller member has a plurality of rollers that can be raised and lowered into contact with the ground. The roller members are provided with a rotatable linkage for lowering and raising the rollers from a position where the rollers are completely out of contact with the ground, thereby allowing the legs of the platform to contact the ground. In the roller lowered position, the legs of the platform are raised off the ground while the rollers are in contact with the ground. A swing handle is rotatable from a storage position in which it is mounted beneath the platform to a position in which it is easily grasped. Thus, a mechanical advantage is created such that a person can easily raise and lower the roller members from the partially raised position to the fully lowered position.
Advantages and novel features of the invention may be set forth with particularity in the appended claims and may be part of a claim. For a better understanding of the present disclosure, its advantages, and its uses, reference is made to the accompanying drawings and descriptive matter in which embodiments are illustrated.
In the drawings, like numerals indicate like parts throughout the several views.
FIG. 1 is an unfolded perspective view of a platform assembly of the present invention;
FIG. 2 is a perspective view of the platform of FIG. 1 shown folded with a platform plate thereon;
FIG. 3 is a partial side view of a folding assist mechanism of the platform of FIG. 1 in a fully open position;
FIG. 4 is a view of the folding assist mechanism of FIG. 3 with the platform in a partially folded condition;
FIG. 5 is a perspective view of a connector system for raising a platform board and for securing the platform boards to a platform frame;
FIG. 6 is a side view of a platen plate with a return plate above another platen plate;
FIG. 7 is a side view through a platform plate with a connector extending to the platform plate in an unlocked state;
FIG. 8 is a side view of the connector of FIG. 7, the connector being in a locked position;
FIG. 9 is a perspective view of a locking mechanism for the platform of FIG. 1 in a partially folded condition;
FIG. 10 is a perspective view of the locking mechanism of FIG. 9 with the platform in an unfolded state and the locking mechanism locked;
FIG. 11 is a perspective view of a lower retaining member holding the deck plate to the deck and in a secure operating position;
FIG. 12 is a perspective view of the retaining member shown in FIG. 11 in an unsecured state;
FIG. 13 is a view of an upper retaining member in a retaining position for retaining a stored platform board on a platform;
FIG. 14 is a side view of a roller member for the folding platform of FIG. 1 in a state where the rollers are fully lowered to contact the ground;
FIG. 15 is the view of the roller assembly shown in FIG. 14, in a partially retracted position, but with the roller still in contact with the ground;
FIG. 16 is the view of the roller assembly of FIG. 14, but with the roller fully raised and the foot in contact with the ground;
FIG. 17 is a perspective view of a cross over device for supporting an adjacent platform plate;
FIG. 18 is a perspective view of a bridging device supporting an adjacent platform plate on both sides of the platform;
FIG. 19 is a perspective view of a four-point bridging device for supporting three deck plates adjacent a deck at a corner;
figure 20 is a view of a storage rack on a platform rack for storing the height, extension risers.
Referring to fig. 1, there is shown a height adjustable folding platform 100 in an unfolded position, ready for use. The platform supports a pair of platform panels 104 and 106 on the support frame 102. when the support frame 102 is folded to the storage position shown in figure 2, the panels 104 and 106 are positioned substantially opposite one another, so that the total area occupied by the platform is substantially reduced, and the panels 104 and 106 are inverted and can be positioned at different levels from one another, such as carpeting or non-sliding floors. The stand 102 has a folding portion 111 connected to the hinge at a central portion and a folding linkage 112, the linkage 112 causing the legs 110 to be generally upright during folding and in the fully folded or unfolded position. The height of the platform may be varied by telescoping members 128 extending outwardly from the legs 110 so that it may be raised or lowered to achieve a desired height of the platform 100. The telescoping member 128 is adjusted by releasing the height, adjusting rod 130, telescoping member 128 having a pad that contacts the ground. The raising, lowering and folding of the platform 100 is performed by means of air springs 114. The size of the spring 114 is determined by the weight of the platform. In addition, the plates 104 and 106 can also be aligned by adjusting the screw 116 at the center of the folded portion 111 of the bracket.
As shown in fig. 3 and 4, the platform 100 has a folding assist device 165, which device 165 assists in the initial folding of the platform from the open position to the final folded position. The fold assist 165 also provides cushioning to the cradle 102 and panels 104 and 106 so that the platform does not immediately fold completely to injure the operator's hand or fingers extending into the cradle. Spring 166 supports a floating strut 170, strut 170 riding on the stationary member of bracket 102. The floating tube portion is guided by a slot 168 provided on this stationary part of the bracket 102. The floating strut 170 supports one member of the folding leg 111. As shown in fig. 3, floating strut 170 is fully depressed when platform 100 is in use. The flipper 166 exerts a constant pressure on the strut 170 against the folding leg 111 even when the platform is in the fully open position. Thus, when the platform 100 is folded under this initial force, the spring 166 pushes the folding leg 111 towards the folded position, thus serving to assist the initial force and also damping the final folding action.
From the fully folded position to the fully open position, the folding linkage does not fold until it engages a floating strut 170 supported by a spring 166 as shown in FIG. 4. The springs 166 and struts 170 prevent the platform from opening fully, so that in addition to the self weight of the platform, a small pressure must be applied to fully open the platform and depress the floating struts 170, as shown in figure 3. In this way, an additional safety feature is provided that reduces the labor associated with folding and unfolding the platform 100.
As shown in fig. 5, the attachment of the support frame 102 to the platform plates 104, 106 is accomplished by connectors 135 inserted into channels 134 of the plates 104, 106. Channels 134 are provided near the corners of each platen plate, but extend through the entire platen plate. Each connector 135 is mounted on a bracket 142 with a cotter pin 144 connected between the brackets 142. the cotter pin 144 is inserted through a hole 146 in each bracket 142 and into a hole 148 in the bracket 102. To raise one platform board 104 relative to another platform board 106, risers 150, 152 can be placed under the boards. The risers 150 or 152 raise the height of the platform boards without simultaneously raising both boards 104, 106. Typically, the risers are 4 inches or 8 inches each. When an 8 inch riser is inserted, a return plate 154 is placed between the raised platen plate 104 and the lower platen plate 106 to block the space (created), as shown in figure 6. It can be seen that the chord riser configuration is achieved by raising the platform board 104 relative to another platform board 106. It can also be seen that the cross-over plates extending between the platforms can be raised by raising the platform plates 104 to create a stretchable chord riser.
As shown in fig. 20, the risers 150 and 152 may be stored on the platform shelf 102 when the platform is not in use. The risers 150 and 152 are mounted on riser receptacles 200 on the storage rack. The risers 150, 152 are slid onto the receptacle 200 from above and then cotter pins are passed through the risers and receptacle 200, whereby the risers remain out of the way.
As shown in fig. 5, the closure pin members 202, which are used to connect and disconnect the cross over plates 108, are connected to complementary closure pin members 204. The crossover 108 is supported on the platform by connectors as explained below.
In fig. 7 and 8, the connection 135 extends through the holes 134 of the plates 104, 106 to about the same height as the upper plane of each platform plate, as shown in fig. 7. The connector is inserted into the platform plate channel 134 using a pin 136 that extends upward from a support 142. A portion of the pin 136 is wider than a flexible compressible portion 138. As the pin 136 is rotated and tightened, the compressible portion 138 expands radially into abutment with the inner wall of the channel 134 as shown in FIG. 8. In this way, a frictional engagement connection between the connector 135 and the channel 134 is formed. Thus, the platform board is held on the support 102. The pin 136 has a flexible base 140, the base 140 allowing slight movement of the pin 136 into alignment with the channel 134. The flexible base 140 is adjacent a stop plate 141 and has a length greater than its width so that when the pin 136 is rotated, the base 140 abuts the stop plate 141 preventing additional rotation of the pin 136, as shown in figure 8. It can be seen that because the bolts are a standard series of bolt heads, a standard hex wrench can tighten the deck plates 104, 106 onto the support 102. In addition, since the connector 135 is a single piece fixed to the frame 102, no additional pieces are required, so that the connector does not fall off when the platform board is fixed to the frame. It can also be seen that the connectors 135 are approximately flush with the surface planes of the platform boards 104, 106.
To lock the platform in the fully open position, a locking linkage 155 is provided which locks the folded half of the bracket, as shown in figure 9. The lock linkage 155 has a pair of cross links 156 and 158 extending between the legs below the respective plates 104, 106. The cross link 156 has a handle 162 for raising and lowering the linkage and a detent 164 for maintaining the linkage in the locked position. The linkage 155 between a pair of opposed legs is connected to a member 160 extending along the centerline of the platform. To lock the platform 100 in the use position, the linkage is pushed down through the elbow joint (shown in phantom) as shown in fig. 10. The linkage 155 is connected to the stop 164 via the toggle joint, the cross link 158, and thus, the linkage is prevented from further folding. Any inward pressure on the linkage mechanism forces the link 158 against the stop 164, thereby preventing the platform 100 from collapsing.
In addition, a spacer linkage 192 between the pair of legs 110 and above one of the locking linkages 155 is used to separate the legs as the platform 100 is adjusted in height. The linkage 192 has links 194 and 196 that extend between the pair of legs and above the locking linkage 155. The isolating linkage 192 folds with the platform, but it works in conjunction with the locking linkage to prevent the platform 100 from folding during height adjustment.
As shown in fig. 2, when the platform 100 is folded, the cross-over panels 108 may be stored on top of the platform panels 104, 106. Plate 108 may expand the platform area of platform 100. Thus, an extended continuous deck can be provided without the need for a shelf under each deck. Storage of the cross-over panels 108 on a folded platform saves storage space and eliminates the need for additional boxes to carry the panels 108. Moreover, since the plates 108 are stored on the platform, the cross-over plates are always easier to reach in their end use position.
The grafts 108 are held to the platform 100 by hooks 172 below the bridge and hooks 174 near the upper edge of the bridge. As shown in fig. 11, the lower hooks 172 extend beyond the edges of the plates 104 or 106 and the cross over plate 108, and these hooks extend above the upper surface of the base of these platform plates and support these platform plates.
As shown in fig. 12, when the hooks are not in use, the lower hooks may be pivoted sideways about the axle 175 and then slid under the deck boards 104, 106. The hook 172 may be placed in a storage or use position by opening or closing a spring-tensioned switch 176. The switch 176 fits into the through holes 177A and 177B of one of the mounts to maintain the hook in the storage or use position. The hole 177A is slightly smaller than the switch 176 so that when aligned with the hole 177A, the switch 176 is slightly restrained, thereby creating resistance to rotation. The hook 172 is not locked in the storage position and the switch 176 is received in the aperture 177B, thereby allowing the switch to be manually depressed when the hook 172 is rotated from the plate retaining position.
As shown in fig. 13, the upper hooks 174 are attached to the folding leg 111, and the hooks are tensioned by springs to tightly hold the respective hooks 174 against the folding leg 111. The spring 178 urges the hook 174 towards the frame 102 as shown in fig. 2, so that the upper portion 181 of the hook 174 rests between the plates 104, 106 and the folding frame 111 during storage. In use, the handle portion 180 is grasped, the hook is pulled away from the folding leg, and it is lifted outwardly and upwardly. Thus, the upper portion 181 of the hook 174 rests on the cross over plate 108 and the spring 178 pulls the upper portion 181 of the hook 174 over the cross over plate 108.
The hooks 172, 174 allow the cross over plate 108 to be stored in the platform without the need for additional tools or parts that are not attached to the platform 100.
As shown in fig. 14-16, the platform 100 has roller members 118 that transport the platform 100 from storage to use. The roller members can raise or lower the platform so that the legs 110 can be disengaged or contact the ground. As shown in figure 14, when the roller member 118 is fully lowered, the rollers contact the ground and cause the legs to lift from the ground, allowing the platform to be transported to a different location. The platform can be transported when the roller members are lowered, whether in a collapsed or an open position. As shown in figure 16, when the roller members 118 are raised, the legs 110 contact the ground and the rollers 120 no longer support the weight of the platform and the platform cannot be removed therefrom (where used).
To raise or lower roller member 118, a handle 122 is secured thereto. The handle is rotatable between its storage position and a use position in which it is capable of exerting its maximum mechanical efficiency. Rotation of the handle 122 is limited by a slot 123 in the handle receiving portion mounted on a beam 124. The beam 124 is provided with rollers 124 and carries them up and down together. The beam is connected to the frame beam 132 by linkages 126A, B, C and D. When handle 122 is moved, roller member 118 is moved from the raised position shown in fig. 16, via the rollers and legs, to contact the ground, (the position shown in fig. 15) to the fully lowered position shown in fig. 14, in which the rollers contact the ground and the legs are raised off the ground. The linkage 126 rotates the beam 124 to raise and lower it relative to the frame 102, the linkage 126 also maintaining parallelism between the rollers and the ground. The center rod 126B collides with a stop 132 on the frame beam 123, preventing further continued rotation of the linkage 126 and maintaining the roller 120 in the lowermost position. In addition, the mounting location of the handle 122 is raised adjacent to the platform boards 104, 106 so that the handle can raise or lower the platform 100 without being adjacent to the ground. In prior art platforms, the handles with the roller members are near the ground.
As shown in fig. 17, to support the cross over plates 108 between the platforms, a cross over support 184 is positioned. The support member 184 includes a connecting member 185 like the single support member 142 that is placed on the folding leg or on the same location on the other platform, and the two-point support member 184 has a reinforcing gusset 186 that supports the second connector 135 inserted into the cross-over plate 108.
In addition to supporting a cross-over plate 108 on one side of the platform, a three-point support 188, as shown in fig. 18, may be used to support the cross-over plate on the other side of the same platform, as with a two-point support. The three-point support is also secured to the platform frame at the same location as the single support 142. The three-point support has one connector for the platform and a plurality of connectors 135 for each cross over plate.
As shown in fig. 19, to achieve a more extended flat deck, a plurality of cross-over plates 108 may be supported on both sides of the deck and between the cross-over plates extending beyond the sides. To support the three cross-over plates 108, a four-point support 190 is introduced, the support 190 being fixed in the same manner as the single-point support, the two-point support and the three-point support.
It is to be understood that the features and advantages of the present invention have been described in the foregoing description, and are described in connection with the structures and principles of the invention, but this is by way of illustration only , the general concept underlying those terms of art in the claims being indicative of the spirit of the invention and various changes may be made in the details, particularly in matters of shape, size, and location of the various elements described and illustrated without departing from the spirit of the invention.