Application Serial Number 08/914,037, filed 08 August 1997 (08.08.97).

This application is related to Application Serial Number 08/759,976 entitled Improved Movable Trench Shoring Device, filed December 3,1996.

DESCR) PT) ON BACKGROUND OF THE INVENTION Technical Field. The present invention relates generally to devices for trench shoring and, more specifically, to a device that may be readily positioned and moved along a length of trench, for shoring the trench.

Background. Trench shoring is used to secure the sides of ditches and trenches which may be occupied by laborers during operations which may occur within the trench, oftentimes in utility construction and maintenance. Trench shoring typically consists of two opposing panels which are held in spaced apart relationship by a plurality of struts or spreaders which may be of a fixed and interchangeable length or in the alternative adjustable in length, thereby adjusting the distance between the spaced apart panels for any given width of ditch.

Once the trench is opened by excavation, the shoring or trench box is set into the trench. Laborers may then enter the trench and work at the bottom in a far safer environment than that which would exist in an open trench. As the trenching advances, additional trench boxes may be placed along the trench or, alternatively, a trench box may be advanced along the length of the trench as it avances with the work. In this case, the box is typically lifted by the hoe or shovel which is performing the excavation and advanced along the length of the trench and then dropped or placed into the trench.

A number of disadvantages are present with this arrangement, including the fact that the trench boxes typically set at the bottom of the ditch which

reduces the clearance between the lower spreaders and the work which is being performed at the bottom of the trench. Additionally, moving the trench box or advancing the box along the trench is a cumbersome and time consuming operation.

A number of solutions have been suggested to address these and other disadvantages. West Jr., U. S. Patent No. 3,788,086, discloses a trench barrier having a horizontal frame carriage with wheels mounted on the ends of the frame carriage. West discloses a carriage having suspended from it a pair of spaced apart shield members which may be held in spaced apart relation by jacks extending between the shield members. West also discloses vertically disposed cooperating telescoping struts which are carried by the carriage for adjusting the relative vertical position of the shield members, and allows for varying the height at which the shield members are suspended in the trench.

However, the device disclosed by West is configured having wall members which extend well past the ends of the frame carriage and the axles, thereby restricting vertical movement of the wall members to a height determined by the elevation of the frame carriage and the axles.

Arnold, U. S. Patent 4,874,271, discloses a trench shoring machine having a main frame having a pair of substantially vertical guide members carried by the main frame, a pair of transversely extending carrier bars engage the pair of vertical guide members, and opposed shoring plates supported from the carrier bars which are moveable along the length of the carrier bars. Arnold further discloses a pair of shoring plates, including a top plate and a lower plate, which are movable between relative upper and lower positions with respect to the main frame, together with means for moving the lower plate between an upper and lower position.

The device disclosed by Arnold allows the shoring plates to be raised above the elevation of the axles, but accomplishes this through a configuration wherein the main frame is suspended through the use of a triangular carrier frame located at each wheel. This configuration results in placement of the substantial weight of the main frame well above the axles. This configuration

results in a raised center of gravity for the apparatus. During operations, which typically occur along an open trench having excavation tailings piled along either side of the trench, the heightened center of gravity may cause a propensity in the apparatus to overturn.

In Spencer, U. S. Patent 5,306,103, a carriage assembly is disclosed which supports a trench box in a suspended relationship having a pair of axles, a pair of spaced apart bracket elements disposed on each axle, a pair of wheel assemblies disposed at opposite ends of each axle and a support member attached to each of the bracket elements in a downwardly depending relation thereto, the support member being connected to the trench box. in Spencer, a support member extends for a portion of its length through rigidifying members located near the outer edges of each of the two trench shields. The overall configuration of the apparatus disclosed by Spencer results in a fairly rigid structure which may be suitable for lightweight panels, fabricated of aluminum for instance, and panels of a limited height and depth. However such a rigid configuration is unsuitable for use with large steel panels used in many applications. Once again, vertical travel of the trench box is limited by the elevation of the frame and axles.

What is needed is an improved trench shoring transport device, for use with large steel trench shoring boxes, which is capable of supporting boxes which may reinforce and support trench banks as shallow as 4 feet and as deep as 25-30 with shoring panels as wide as 36 feet. What is also needed is a portable or moveable trench shoring transport device which provides a support means for the shoring box which allows for adjustment of the height of the shoring box or panels relative to the frame so that the top edge of the panel shoring box or panels may be adjusted above the elevation of the frame, thereby providing increased flexibility in the working dimensions of the device so that it may accommodate a variety of ditch depths without having to interchange larger panels for shorter panels. Additionally, it would be advantageous to have a trench shoring transport device which allows for variation and adjustability of the wheel base width. Additionally, it would be advantageous to have a trench

shoring transport device which provides a means for splitting an upper and a lower pair of trench boxes when an obstacle is encountered in excavation.

Additional objects, advantages and novel features of the invention will be set forth as part of the description that follows and, in part, will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention.

SUMMARY OF THE INVENTION According to the invention, these and other objects are achieved by a trench shoring transport device which allows the device to be moved along a surface adjacent to the trench. The device includes a frame having a pair of side frame subassemblies slideably and adjustably attached to one another. The frame is supported by four wheel assemblies, one wheel assembly located near each of the four corners of the frame. The device's configuration allows the frame to be arranged having a range of possible widths and hence a range of possible wheel base widths.

A trench box, or a plurality of trench boxes each having a pair of opposing panels and a plurality of spreaders for maintaining the relative distance between the trench box panels are suspendable from the frame. The trench box is suspendable from a pair of powered vertical support members which are located one at each end of the trench box. In the preferred embodiment of the invention, the powered vertical support members are hydraulically actuated. The vertical support members are attached to the frame and the trench box employing connectors which allow for a wide range of freedom of movement about the connection, thereby substantially reducing the risk of bending or breaking the various structural elements of the device.

The pair of hydraulically actuated vertical support members are sized and configured to lift and lower the trench box within the frame. Additionally, the disclosed configuration allows the trench box to be raised or lifted between the elements of the frame permitting a broad range of height configurations for the

movable trench shoring device including height configurations wherein the top of the trench box is raised above the elevation of the frame.

In addition, the degree of freedom of movement between the various components of the frame, the hydraulically actuated vertical support members and the spreaders permit the device to adapt to a variety of trench configurations without binding within the trench during operations and while advancing the device in the trench, thereby substantially reducing the risk of damage to the device and its various component parts.

In addition, in those cases where the trench shoring transport device is configured having an upper and a lower pair of trench boxes, one embodiment of the present invention provides a means for splitting the upper and a lower pair of trench boxes when an obstacle is encountered in excavation allowing the obstruction to pass between the pair of trench boxes, thereby permitting work to progress in a substantially uninterrupted manner.

Additional objects, advantages and nove ! features of the invention will be set forth in part in the description that follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective representational view of the trench shoring transport device; Fig. 2 is a first end representational view of the trench shoring transport device; Fig. 3 is a second end representational view of the trench shoring transport device; Fig. 4 is a side representational view of the trench shoring transport device; Fig. 5 is a cutaway side representational view of the trench shoring transport device;

Fig. 6 is a top representational view of the trench shoring transport device; Fig. 7 is an exploded detail perspective representational view of the frame portion of the trench shoring transport device; and Fig. 8 is a schematic representational view of the hydraulic power unit of the trench shoring transport device.

DETAILED DESCRIPTION OF THE INVENTION Referring now to Figures 1 through 5, the trench shoring transport device 10 will be more fully described and understood. Figure 1 is a perspective representational view of trench shoring transport 10 showing various elements and components of the device, including frame 20. Frame 20 includes generally a first side frame sub-assembly 21 and second side frame sub-assembly 22.

Each side frame sub-assembly in turn includes a number of components.

First side frame sub-assembly 21 includes first side frame side member 23 which extends from the front to the rear of the apparatus. In the preferred embodiment of the invention, attached at either end are first side frame first end box member 25 and first side frame second end box member 29. First side frame first end box member 25 includes first side frame first end member 26, first side frame first end inboard frame member 27, and first side frame first end transverse member 28. Similarly, first side frame second end box member 29 includes first side frame second end member 30, first side frame second end inboard frame member 31, and first side frame second end transverse member 32.

Second side frame sub-assembly 22 is basically a mirror image of first side frame sub-assembly 21, and includes second side frame member 24 which extends from the front of the apparatus to the rear. Second side frame sub- assembly 22 also includes second side frame first end box member 33 and second side frame second end box member 37. Second side frame first end box member 33 includes second side frame first end member 34, second side frame first end inboard frame member 35, and second side frame first end transverse

member 36. Similarly; second side frame second end box member 37 includes second side frame second end member 38, second side frame second end inboard frame member 39, and second side frame second end transverse member 40.

By design, the various frame box end members provide required structural rigidity for the apparatus and, in addition, second side frame second end box 37 provides a protective bay for hydraulic power unit 200 which contains the various hydraulic components including the power plant, pump, and hydraulic reservoir described herein below.

First side frame sub-assembly 21 and second side frame sub-assembly 22 are slideably and adjustably engaged one to the other by a pair of telescoping frame members. First frame end telescoping member 60 engages first side frame first end member 26 and second side frame first end member 34.

Similarly, second frame end telescoping member 61 slideably engages first side frame second end member 30 and second side frame second end member 38.

Each side frame sub-assembly also includes a number of side frame vertical members. First side frame sub-assembly 21 includes first side frame first vertical member 41 and first side frame second vertical member 43, both attached at their upper ends to first side frame first end inboard frame member 27. First side frame sub-assembly 21 also includes first side frame third vertical member 45 and first side frame fourth vertical member 47, each attached at their upper ends to first side frame send end inboard member 31.

Similarly, second side frame sub-assembly 22 includes second side frame first vertical member 49 and second side frame second vertical member 51, each attached at their upper ends to second side frame first end inboard frame member 35. Finally, second side frame sub-assembly 22 includes second side frame third vertical member 53 and second side frame fourth vertical member 56 attached at their upper ends and extending below second side frame second end inboard frame member 39.

A lower structural element extends the length of each side frame sub- assembly. The first side frame sub-assembly 21 includes first side frame

spanner 58 which attaches to the lower ends of first side frame first vertical member 41 by first side frame first vertical connector 42, first side frame second vertical member 43 by first side frame second vertical connector 44, first side frame third vertical member 45 by first side frame third vertical connector 46 and first side frame fourth vertical member 47 by first side frame fourth vertical connector 48. Similarly, second side frame sub-assembly 22 includes second side frame spanner 59 which attaches to second side frame first vertical member 49 by second side frame first vertical connector 50, second side frame second vertical member 51 by second side frame second vertical connector 52, second side frame third vertical member 53 by second side frame third vertical connector 54, and second side frame fourth vertical member 56 by second side frame fourth vertical connector 57.

Frame 20 further includes first transverse spanner 62 and second transverse spanner 70 which extend across the width of the frame 20 which, together with first frame end telescoping member 60 and second frame end telescoping member 61 hold first side frame sub-assembly 21 and second side frame sub-assembly 22 in sliding and adjustable engagement with each other.

First transverse spanner 62 includes first transverse spanner first end 63 and first transverse spanner second end 66. First transverse spanner first end 63 is pivotally attached to first side frame sub-assembly 21 by first transverse spanner hinged connector 64 and first transverse second hinged connector 65.

Similarly, first transverse spanner second end 66 is pivotally attached to second side frame sub-assembly 22 by first transverse third hinged connector 67 and first transverse fourth hinged connector 68. First transverse spanner first end 63 and first transverse spanner second end 66 are slidably engaged with one another by first transverse spanner telescoping member 69.

Second transverse spanner 70 includes second transverse spanner first end 71 and second transverse spanner second end 74. Second transverse spanner first end 71 is pivotably attached to first side frame sub-assembly 21 by second transverse first hinged connector 72 and second transverse second hinged connector 73. Similarly, second transverse spanner second end 74 is

pivotally attached to second side frame sub-assembly 22 by second transverse third hinged connector 75 and second transverse fourth hinged connector 76.

Second transverse spanner first end 71 and second transverse spanner second end 74 are slideably and adjustably engaged by second transverse spanner telescoping member 77.

In the preferred embodiment of the invention, a means for adjusting the length of first transverse spanner 62 and second transverse spanner 70 and thereby the overall width of frame 20. One embodiment of the invention includes first adjustment screw 78 which passes through the length of first transverse spanner 62 and second adjustment screw 79 which passes through the length of second transverse spanner 70. By rotating first adjustment screw 78 and second adjustment screw 79. Each adjustment screw is effectively a leadscrew which passes through a pair of fixed carriages, one carriage located within each of the two transverse spanner end members. As the adjustment screw is rotated, the transverse spanner is lengthened or shortened, depending upon the direction of rotation.

An alternate embodiment of the invention allows the length of trench shoring transport 10 to be adjustable by fabricating first side frame side member 23, second side frame side member 24 first side frame spanner 58 and second side frame spanner 59 as telescoping members.

In the preferred embodiment of the invention, all structural components are formed of commonly available structural steel shapes, including square and rectangular steel tubing and plate. The trench shoring transport 10, however, may be manufactured of other materials having adequate structural characteristics.

Frame 20 is supported by a number of wheel assemblies as shown in the figures. In the present embodiment depicted herein, frame 20 is supported by first wheel assembly 80, second wheel assembly 85, third wheel assembly 90 and fourth wheel assembly 95. First wheel assembly 80 includes first wheel assembly axle 81 which attaches at first side frame side member 23. First wheel assembly arm 82 is pivotally attached to first wheel assembly axle 81 and

allows first wheel assembly lead wheel assembly 83 and first wheel assembly trailing wheel assembly 84 to rotate freely about first wheel assembly axle 81 allowing the wheel assembly to adjust as required to variations in the topography located along beside an excavated trench. Similarly, second wheel assembly 85 attaches at second side frame side member 24 by second wheel assembly axle 86. Second wheel assembly arm 87 is pivotally attached to second wheel assembly axle 86. Second wheel assembly lead wheel assembly 88 and second wheel assembly trailing wheel assembly 89 are attached at either end of second wheel assembly arm 87.

Located near the front end of frame 20 are third wheel assembly 90 and fourth wheel assembly 95.

First wheel assembly 80 includes first wheel assembly axle 81 which attaches to and extends horizontally from first side frame side member 23.

Pivotally attached to first wheel assembly axle 81 is first wheel assembly arm 82 which pivots freeiy on first wheel assembly axle 81. Mounted to first wheel assembly arm 82 are first wheel assembly lead wheel assembly 83 and first wheel assembly trailing wheel assembly 84. Similarly, second wheel assembly 85 includes second wheel assembly axle 86 which attaches to and extends horizontally from second side frame member 24. Second wheel assembly arm 87 is pivotally attached to second wheel assembly axle 86. Second wheel assembly lead wheel assembly 88 and second wheel assembly trailing wheel assembly 89 are attached at either ends of second wheel assembly arm 87.

In the preferred embodiment, the front end of frame 20 is supported by third wheel assembly 90 and fourth wheel assembly 95. Third wheel assembly 90 includes third wheel assembly axle 91, third wheel assembly arm 92, third wheel assembly lead wheel assembly 93 and third wheel assembly trailing wheel assembly 94.

On the opposing side of frame 20 is fourth wheel assembly axle 96 includes fourth wheel assembly arm 97, fourth wheel assembly lead wheel assembly 98 and fourth wheel assembly trailing wheel assembly 99.

In the preferred embodiment of the invention, each of the lead wheel assemblies and the trailing wheel assemblies are castors which allow 360° of free rotation which facilitates positioning of the frame in the working environment.

Suspendable from frame 20 is upper trench box 11, including first trench box panel 12 and second trench box panel 13, which are held in spaced apart relationship by first spreader 14, second spreader 15, third spreader 16 and fourth spreader 17. The various spreaders may be of a fixed length or may be adjustable in length.

Upper trench box 11 depends from frame 20 by first hydraulic arm 110 and second hydraulic arm 113. First hydraulic arm 110 is pivotally attached to first hydraulic arm first end connector 111 which extends from first transverse spanner 62. Similarly, second hydraulic arm 115 is pivotally attached to second hydraulic arm first end connector 14 which attaches to and extends from second transverse spreader 70.

A means for attaching the second end of first hydraulic arm 110 and the second end of second hydraulic arm 113 to trench box 11 is provided. In the preferred embodiment of the invention the means for attachment takes the form of a pair of separate spreaders shown in Figures 2 and 3, as first auxiliary spreader 101 and second auxiliary spreader 102. First auxiliary spreader 101 attaches between trench box first lower ear 103 and trench box second lower ear 104. Similarly, second auxiliary spreader 102 attaches between trench box third lower ear 105 and trench box fourth lower ear 106. The second end of first hydraulic arm 110 is pivotally attached to first hydraulic arm second end connector 112 which is configured as a sleeve which is slidably mountable on first auxiliary spreader 101. Similarly, the second end of second hydraulic arm 113 is attached to second hydraulic arm second end connector 115 which is also configured as a collar which is slidably mountable on second auxiliary spreader 102.

In an alternate embodiment of the invention, as shown in Figure the second end of first hydraulic arm 110 is pivotally attached to first hydraulic arm

second end connector 112 which is configured as a sleeve which is slidably mountable on first spreader 14. Similarly, the second end of second hydraulic arm 113 is attached to second hydraulic arm second end connector 115 which is also configured as a collar which is slidably mountable on third spreader 16. It should be specifically noted that, while the figures depict second end connectors located on the upper spreaders, these second end connectors are slidably mountable on any of the trench box spreaders as required for operation of trench shoring transport 10.

In the preferred embodiment of the invention, a means for adjusting the length of first hydraulic arm 110 and second hydraulic arm 115 is provided.

This means is preferably provided by a hydraulic power unit. As shown in Figure 7 hydraulic power unit 200 includes power plant 201 which is typically a gasoline engine although other options are commonly available and pump 202.

Pump 202 is operative connected to hydraulic reservoir 203 and to first hydraulic arm 110 and second hydraulic arm 115 through controls 204 by hoses 205.

As shown in Figure 1, the trench boxes may be connected in series employing H-clips 157. As shown in Figure 1, lower trench box 150 includes third trench box panel 151 and fourth trench box panel 152. These panels are held in spaced apart relationship by fifth spreader 153, sixth spreader 154, seventh spreader 155 and eighth spreader 156.

Another feature of one embodiment of the present invention allows upper trench box 11 to be split or separated from lower trench box 150 during operations. This feature is useful where a pipeline is encountered during excavation of a new trench, said pipeline running transverse to the excavation.

In the preferred embodiment of the invention, the means for splitting the upper trench box from the lower trench box during operation includes first chain 124, second chain 125, third chain 126 and fourth chain 127.

As shown in Figure * *, the first end of first chain 124 is secured within first frame chain eye 128 which is secured to frame 20. Similarly, the first end of second chain 125 is secured within second frame chain eye 129. The first

end of third chain 126-is secured within third frame end chain eye 130 and the first end of fourth chain 127 is secured within fourth frame end chain eye 131.

The second end of first chain 124 is attachable to trench box first attachment point 132. The second end of second chain 125 is attachable to trench box second attachment point 133. Similarly, the second end of third chain 126 is attachable to trench box third attachment point 134 and the second end of fourth chain 127 is attachable to trench box fourth attachment point 135.

In an alternate embodiment of the invention shown in Figures 3 and 4, the means for splitting the upper trench box from the lower trench box during operation includes first auxiliary bar 116 includes first auxiliary bar collar 117 which is slidably mountable to a trench box spreader. Specifically, first auxiliary bar 116 is mounted to fifth spreader 153. Located at the second end of first auxiliary bar 116 is first auxiliary bar eye 118. In operation, first auxiliary bar is configured to rotate on the spreader from a vertical hanging position to a horizontal position where rotation of the auxiliary bar is limited by first auxiliary bar stop 119 thereby holding first auxiliary bar 116 is a horizontal position.

Similarly, second auxiliary bar 120 includes second auxiliary bar collar 121 which is slidably mountable, in this case, to seventh spreader 155. Second auxiliary bar 120 also includes second auxiliary bar eye 122 and second auxiliary bar stop 123.

As shown in Figure 4, first chain 124 depends from first frame chain eye 125. Similarly, second chain 126 depends from second frame chain eye 127.

When transverse pipe P is encountered in excavation, upper trench box 11 may be split by engaging the second end of first chain 124 in first auxiliary bar eye 118. H-clips 157 may then be removed, splitting the upper and lower halves of upper trench box 11 allowing transverse pipe P to pass through the box panels.

This operation is repeated at both ends of the box as the excavation proceeds.

Trench shoring transport 10 may also inclue, in various embodiments, a pipe laydown rack or a work platform 140, as shown in Figure 1.

In use, trench shoring transport 10 is first positioned over a ditch. This is accomplished with a truck, tractor or other powered implement located at the

excavation site (not shown). Once frame 20 is positioned directly over the open trench or excavation, first trench box 11 is lowered between first side frame spanner 58 and second side frame spanner 59. In the event that the distance between first side frame spanner 58 and second side frame spanner 59 needs to be adjusted, first side frame subassembly 21 and second side frame subassembly 22 may be moved nearer to one another or farther away effectively adjusting the distance between the side frame spanners and hence the wheel base of power trench shoring transport 10.

Trench box 11 depends from frame 20 by first hydraulic arm 110 and second hydraulic arm 113. First hydraulic arm 100 attaches to frame 20 at its first end to first hydraulic arm first end connector 111 and at its second end to trench box 11 by first hydraulic arm second end connector 112. Similarly, second hydraulic arm 113 attaches to frame 20 at its first end to second hydraulic arm first end connector 114. The second end of second hydraulic arm 113 attaches to trench box 11 at second hydraulic arm second end connector 115.

Trench box 11 may then be raised and lowered by activating controls 204 for hydraulic power unit 200.

Additional trench boxes may be attached as shown in the figures using H- clips 157 which attached at their upper ends to first trench box panel 12 and second trench box panel 13 and at their second ends to third trench box panel 151 and fourth trench box panel 152 of second trench box 150.

In one embodiment of the present invention, second trench box 150 includes a pair of auxiliary arms for allowing the operator of the power shoring transport device 10 to split the first trench box 11 and second trench box 150 when obstacles are encountered within the excavation.

As trench shoring transport device 10 approaches an obstacle such as a pipeline laying transverse to the excavation, as shown in Figure 5, auxiliary bar 116 is rotated to a horizontal position where its motion is restricted by first auxiliary bar stop 119. The upper end of first chain 124 is inserted in first frame end chain eye 125. In this position, the second end of first chain 124 hangs

directly over the end of first auxiliary bar 116. Next, first hydraulic arm 110 is lowered to a position as shown in Figure 4, which will allow passage of the obstacle when the first trench box 11 is separated from second trench box 150.

The second end of first chain 124 is inserted through first frame auxiliary bar eye 118. At this point, the weight of both first trench box 11 and second trench box 150 may be supported directly by first chain 124. H-clips 157 and 158 may now be removed and first trench box 11 raised by operation of first hydraulic arm 110 to split the boxes as shown in Figure 4. The opposite end of the trench boxes may be split by following the same procedure. One the obstacle has passed the trench boxes, the trench boxes may be reattached and the auxiliary arms disconnected and swung out of the way.

While there is shown and described the preferred embodiment of the invention. it is to be distinctly understood that this invention is not limited thereto but may be variously embodied to practice within the scope of the following claims.

I claim: