|Publication number||US3791151 A|
|Publication date||Feb 12, 1974|
|Filing date||Nov 8, 1972|
|Priority date||Nov 8, 1972|
|Also published as||CA978512A, CA978512A1, DE2264164A1|
|Publication number||US 3791151 A, US 3791151A, US-A-3791151, US3791151 A, US3791151A|
|Original Assignee||Plank D|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (5), Referenced by (22), Classifications (13)|
|External Links: USPTO, USPTO Assignment, Espacenet|
United States Patent [191 Plank SHORING APPARATUS v  Inventor: David O. Plank, PO. Box 12591,
Houston, Tex. 77017  Filed: Nov. 8, 1972  Appl. No.: 304,824
 US. Cl. 61/41 A, 61/63  Int. Cl. E2111 5/00  Field of Search. 61/41 A, 41, 63; 92/165, 108,
 References Cited UNITED STATES PATENTS 3,224,201 12/1965 Brunton 61/41 A 3,362,167 1/1968 Ward 61/41 'A 804,696 11/1905 Winterhoff... 61/39 X 3,172,339 3/1965 Quayle 92/51 FOREIGN PATENTS OR APPLICATIONS 1,601,715 8/l970 Germany 92/108 [4 1 Feb. 12, 1974 Primary Examiner-Dennis L. Taylor  ABSTRACT A hydraulic shoring apparatus including oppositely positioned trench rails adapted for placement against the sides of a trench or other excavation and hydraulic jack means pivotally connected with the trench rails. The hydraulic jack means including a hydraulic cylinder having a piston slidably mounted therein, the piston having a rod adjustably attached therewith whereby the application of hydraulic fluid under pressure into the cylinder causes movement of the piston and rod to an extended position such that the trench rails are maintained against the sides of the trench. Protective sleeve means are mounted over the cylinder and rod with the rod in the extended position in order to protect both the cylinder and the rod from damage.
3 Claims, 5 Drawing Figures sbmmm PATENTEDFEB 12 m4 SHEET 2 [1F 2 SHORING APPARATUS BACKGROUND OF THE INVENTION The field of this invention is hydraulic shoring.
Various devices have been used in the prior art to shore up the sides of a trench or other excavation in order to prevent a potentially dangerous collapse of the trench sides. For example, timber and steel have been used to provide structural bracing; mechanical jacks have also been used to provide reinforcement against the sides of trenches. One very effective type of shoring apparatus is a hydraulic shoring apparatus such as disclosed in US. Pat. No'. 3,224,20l, issued to Brunton. The Brunton US. Pat. No. 3,224,201 discloses the use of a hydraulic jack assembly connected to rails to shore trench sides. One'of the difficulties in utilizing the device illustrated in the Brunton US. Pat. No. 3,224,201 is that the hydraulic cylinder of the hydraulic jack assemblies are .exposed to dirt, debris and fluid. Over a period of time, the dirt, debris or water may work or seep into the between the moving parts of the hydraulic jack assembly thereby causing damage which must be repaired.
US. Pat. No. 3,362,167, issued to Ward, discloses an oversleeve which is adapted to be mounted over the rod and cylinder of the hydraulic jack assembly in order to protect the rod when it is moved to an extended position.
SUMMARY OF THE INVENTION It is an object of this invention to provide a new and improved shoring apparatus to further prevent the entry of dirt, debris or fluid into the mechanism. In the preferred embodiment of this invention, the hydraulic shoring apparatus includes spaced trench rails which are pivotally interconnected by means of an hydraulic jack means. The hydraulic jack means includes an hydraulic cylinder having a piston slidably mounted therein. A rod is attached to the piston and the cylinder is pivotally attached to one of a pair of spaced trench rails while the rod is pivotally attached to the other of the spaced trench rails. In order to protect the cylinders as well as the rod, sleeve protective means are provided for mounting over both the cylinder and rod, even with the rod in the extended position, in order to protect against dirt and debris.
The protective sleeve means includes a first sleeve mounted over the rod and a second sleeve mounted over the first sleeve and the cylinder. The first and second sleeves are in slidable engagement with each other and seal means are provided between the first and second sleeves and between the first sleeve and the cylinder in order to prevent the entry of fluid into the hydraulic cylinder and piston and rod mechanism.
In another embodiment of this invention, a spiraled,
- 2 block which pivotally connects the rod to one of the trench rails.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is aperspective view of the hydraulic shoring apparatus of the preferred embodiment of this invention;
FIG. 2 is a sectional view taken along line 2-2 of FIG. 1 of a hydraulic jack assembly of the preferred embodiment of this invention;
FIG. 3 is a sectional view taken along line 3-3 of FIG. 2 of the cylinder and fluid transfer block of this invention; and
FIG. 4 is a top view of an alternate embodiment of the protective sleeve means of this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, the letter S generally designates a hydraulic shoring device for supporting or shoring the sides of a trench, ditch or other excavation. The shoring apparatus S includes oppositely positioned trench rails 10 and 11 which are interconnected and moved between collapsed andv extended positions by means of upper and lower hydraulic jack mechanisms generally designated as 12 and 13, respectively. The upper hydraulic jack mechanism 12 is connected with the lower hydraulic jack mechanism 13 by hose 14 and a supply hose 15 is also connected to the upper jack mechanism whereby hydraulic fluid under pressure can be provided to actuate both hydraulic jack mechanisms telescoping sleeve is mounted over both the cylinder and the rod in the extended position and is moved to a retracted position when the rod is moved to a retracted position. I
It is a further object of this invention to adjust the effective length of the hydraulic jack assembly in the ex-' 12 and 13 substantially simultaneously. Of course, the fluidic interconnection of the upper jack mechanism 12 and the lower jack mechanism 13 also provides for coordinated movement of the hydraulic jack mechanisms.
The rail 11 is an elongated, flat metal rail having a substantially flat outside surface 110 adapted to press against and support a portion of the side of a ditch, trench or other excavation. Support ribs 11b and 11c extend inwardly from inside surface 11d of the rail 11 longitudinally throughout the length of the rail. Each of the ribs suchas the rib 11b has, in cross-section as viewed in FIG. 2, an L shape formed of portions He and 11f. A fillet 11g is formed with theportions lle and 11f to further strengthen the support rib 11b. Similarly, the support rib 11c is L-shaped.
The oppositely positioned rail 10 has a flat outside surface 10a and support ribs 10b and extending longitudinally of the rail from inside surface 10d thereof. The support ribs 10b and 100 are similar in cross-sectional configuration to support ribs 11b and 110.
nism 12 is illustrated in cross-section in connection with opposing rails 10 and 11. It should be understood that the lower hydraulic jack mechanism 13 is basically identical in structure to the upper hydraulic jack mechanism 12; therefore, number and letter designations applied to the upper jack mechanism 12 will also apply to the lower jack mechanism 13, with certain limited exceptions noted herein.
The upper hydraulic jack mechanism 12 includes a cylinder 16 having a threaded outer end portion 16a. A cylinder pad 17 (FIG. 3) includes a threaded opening 17a adapted to threadedly engage the threaded end portion 16a of the cylinder. An O-ring seal 18a is mounted in annular groove 17b in the cylinder pad 17. Further, an annular, resilient seal 18b is positioned between the O-ring 18a and the end face 16b of the cylinder 16 in order to prevent the passage of fluid between the cylinder pad 17 and the cylinder end portion 16a.
Referring to FIGS. 2 and 3, the cylinder pad or block 17 further includes a bolt opening 170 which is adapted for alignment with openings 11b and 11c in rail support ribs 111; and 11c, respectively. A bolt 19 extends through rib opening 11b, bolt opening 170 and rib opening 11c and is fastened by means of a nut 19a or other suitable means. In this manner, thecylinder pad 17 cooperates with bolt 19 to pivotally mount the cylinder 16 for pivotal movement with respect to the rail 11.
The cylinder pad 17 includes a first port or bore 17d which is in fluid communication with a second threaded port or bore 172 through a chamber 17f which opens up into threaded opening 17a. A passage 17g interconnects the threaded port 17d with the chamber 17f. The hydraulic fluid supply hose includes a male coupler element 15a which is threaded into connection with the port 17d in the pad 17 for the upper hydraulic jack mechanism 12. Further, the hydraulic line 14 is connected into the threaded port 17a of the pad 17 for the upper jack mechanism by means of a male coupler (not shown). The hydraulic hose 14 is also connected by a male coupler 14a to the port 17a for the lower hydraulic jack assembly. The port 17e of the cylinder pad 17 for the lower jack mechanism 13 is plugged by any suitable threaded plug (not shown). Thus hydraulic fluid under pressure enters through the supply line 15 into the cylinder pad 17 for the upper hydraulic jack assembly 12 and passes through the upper cylinder pad 17, through hose l4 and into the cylinder pad 17 for the lower jack assembly 13 such that hydraulic fluid under pressure is supplied to both upper and lower jack assemblies 12 and 13 substantially simultaneously.
Referring again to the upper hydraulic jack assembly 12 illustrated in FIG. 2, a piston 20 is slidably, sealably mounted for movement within the bore 160 of the cylinder 16. The piston 20 includes a main body portion 200 having an annular recess 20b. A shaft 21 is mounted in the piston 20 and includes threaded end portions 21a and 21b which extend outwardly from the piston 20. A piston head plate 200 is mounted onto threaded shaft end portion 21b and is secured thereto by nut 20d or other suitable means. The recess 20b, which is annular in configuration, receives an annular seal 22 which includes a lip portion 22a which is urged into slidable, sealing engagement with the cylinder bore 166 by the application of hydraulic fluid under pressure from within the chamber C within the cylinder 16 formed by the piston 20. A hollow rod 23 is threadedly mounted over threaded shaft end portion 21a so that the rod-is firmly mounted with the piston 20. I
Referring to FIGS. 2 and 5, a rod block or pad 24 having a bolt opening 24a which is adapted to be aligned with support rib openings 10b and 100'. A bolt 25 extends through the support rib opening 10b and 100' and through the bolt opening 240 in the rod pad 24 and is secured by nut 25a or other suitable means. The rod pad 24 is thus pivotally mounted for pivotal movement with respect to the trench rail 10. Referring in particular to FIG. 5, it is noted the bolt opening 24a is located at lower end 24b of the rod pad 24. In contrast, referring to FIG. 1, the cylinder pads 17 are pivotally attached to the trench rail 11 at their upper end for rotation about the upperend. However, the rod pad 24 for both the upper and lower jack assemblies 12 and 13, respectively, are pivotally connected about lower pad end 24b for rotation thereabout.
A threaded stud 26 is threadedly mounted into threaded opening 240 in the rod pad 24. The direction of the threaded portion 26a of the threaded stud 26 mounted in the rod pad 24 is opposite from the thread direction of the remaining threaded portion 26b of stud 26. For example, threaded portion 26a may have lefthanded threads and threaded portion 26b may have right-handed threads.
The hollow rod 23 further includes threaded end portion 23b having right-handed threads so that the hollow rod 23 can be threadedly mounted onto threaded portion 26b of the stud 26 such that the rod 23 is attached to the rod pad 24, which is mounted for pivotal movement with respect to the trench rail 10. A locking pin such as a cotter pin 27 may be mounted in aligned openings in the threaded rod 23 and threaded stud 26 in order to secure the rod pad 24 against rotation with respect to rod 23.
The rod block 24 includes an annular ridge portion 24d which is formed integrally therewith and extends inwardly. The annular ridge 24d can also be a pipe segment which is welded or otherwise mounted onto the rod pad 24. A protective sleeve 30 having an inside diameter substantially equal to the outside diameter of the annular rod pad ridge 24d is mounted over the rod pad ridge 24d. Set screws 31 extend through the protective sleeve 30 into engagement with the annular ridge 24d to mount and secure the protective sleeve 30 to the rod pad 24. The length of the protective sleeve 30 is such that an end portion 30a thereof slidably mounts over the cylinder 16 even when the piston 20 and rod 23 are fully extended. This fully extended position for the protective sleeve 30 is illustrated schematically in FIG. 2. In the fully extended position for the piston 20 and rod 23, the piston 20 is located substantially at cylinder end 16d as designated by the letter E. When the piston 20 and rod 23 are in the fully retracted position, the piston 20 is substantially adjacent threaded sleeve end portion 16a as designated by the letter R. In the retracted position, the protective sleeve 30 is telescoped substantially completely over the cylinder 16. Seal means in the form of an O-ring 32 is mounted in a groove 30b at sleeve end 30a in order to prevent the passage of fluid between the sleeve 30 and the cylinder 16.
A pipe section 33 is mounted onto inside face 17h of the cylinder pad 17 and extends inwardly toward rail 10. The pipe segment 33 may be welded or otherwise attached to the inside face 17h. If desired, the pipe segment 33 may be formed integrally with the rod pad. An outer protective sleeve 35 is mounted over the annular pipe segment 33 and is secured thereto by set screws 36. The outer protective sleeve 35 extends into slidable engagement over the inside protective sleeve 30, even when the piston 20 and rod 23 are in the fully extended position E. An O-ring 37 is mounted in a groove 35a in the outer protective sleeve 35 and slidably, sealably mounts the outer protective sleeve 35 for slidable, sealable movement over the inner protective sleeve 30. When the piston 20 and rod 23 are moved to the retracted position R heretofore described, the inner sleeve 30 telescopes within the outer sleeve 35 thereby providing double protection for the cylinder 16. Therefore, in utilizing the protective inner sleeve 30 and outer sleeve 35, both the rod 23 and the cylinder 16 are protected against falling debris, dirt and fluid even when the piston 20 and rod 23 are in the extended position E heretofore described.
Referring to FIG. 4, the basic hydraulic shore S is again illustrated but, in the embodiment of FIG. 4 a spiraled, telescoping sleeve is mounted over the cylinder 16 and rod 23. The small end 40a of the spiraled sleeve 40 is mounted within annular ridge 24d of the rod pad 24. The larger end 40b of the spiraled sleeve is mounted within the annular ridge or pipe segment 33 attached to the cylinder pad 17. The spiraled sleeve acts to expand as the piston 20 and rod 23 are moved to the extended position illustrated in FIG. 4 and to contract to a collapsed position when the piston 20 and rod 23 are moved to the collapsed, retracted position. The spiraled sleeve 40 is formed substantially of a continuous metal piece which is spiraled into a telescoping shape such that individual windings such as 400 are telescoped within adjacent, larger windings such as 40d when the spiraled sleeve is contracted between rod pad 24 and cylinder pad 17. Such a spiraled sleeve is disclosed in US. Pat. No. 3,300,042.
The general operation and use of the hydraulic shoring apparatus S of this invention may be described as operating in the following manner. The trench rail 11 has a handle 42 pivotally mounted onto the upper end thereof by any suitable means. Similarly, the trench rail has a handle 43 pivotally mounted onto the upper end thereof. The hydraulic shoring apparatus S is low ered into a ditch or trench utilizing hooks (not shown) attached onto the handles 42 and 43. Generally, the shoring apparatus S is in a folded position when it is first lowered into a trench. In the folded position, the upper and lower hydraulic jack assemblies are positioned at acute angles with respect to the rails 10 and 11. This folded position is accomplished by moving rail 10 in the direction of arrow 44 or rail 11 in the direction of arrow 45, or by moving both rails in these respective directions simultaneously. As the shoring apparatus S is moved to the folded position described, the cylinder pads 17 pivot about upper ends 17c thereof and the rod pads 24 pivot about lower ends 24b thereof.
With the hydraulic shoring apparatus S positioned within the trench, the rail 11 is abutting one side of the trench. A hook may then be utilized in handle 43 to lower the rail 10 until the upper and lower hydraulic jack mechanisms 12 and Bare substantially perpendicular to the rails 10 and 11. When the hydraulic jack mechanisms 12 and 13 are substantially perpendicular to the rails 10 and 11, force transferring face 171' of the cylinder pads 17 abut inside surface 11d of rail 1 1. Similarly, force transferring surfaces 24e of rod pads 24 abut inside rail surface 10d. These force transferring surfaces, 24e for rod pads 24 and l7i for cylinder pads 17, abut against the inside rail surfaces 10d and 11d,
fully (through hose 14) whereby the piston and rod 23 attached thereto are moved outwardly to the extended position E. In that position, the effective distance d of the rails 10 and 11 (the distance between rail surfaces 10a and 11a) is at a maximum and rail 10 is abutting the other side of the trench being shored. Thus the trench sides are shored and maintained by the resistive force of the hydraulic fluid under pressure in the cylinders 16. It should be understood that the rails 10 and 11 may be moved to less than the maximum position represented by the letter d and thus maintain and shore the sides of more narrow trenches.
lt should be noted that the threaded port 17d in each cylinder pad 17 has an axis 450 that is positioned at an angle of 7 with respect to the axis 45b of the cylinder 16 (line 45c being parallel to axis 45b). It has been found that the positioning of the port 17d at such an angle provides less resistance to the removal of hydraulic fluid from chambers C of the cylinders 16 when it respectively, and prevent further rotation of the shoris desired to move the rails, piston 20 and rod 23 to the retracted position R (as schematically shown for piston 20).
There are occasions when the width of the ditch or trench being shored is greater than the maximum effective width of the hydraulic shoring apparatus, which is generally represented by the letter d. In this situation, it is desirable to lengthen the effective length of the ho]- low rod 23. This is accomplished by rotating the hollow rod 23 with respect to piston shaft 21 thereby moving rod end 230 away from the piston 20. The effective length of the rod 23 can be further expanded by removing the lock pin 27 and by removing the bolt 25 from the rod pad 24. Then, the rail 10 can be removed and the rod pad 24 is rotated to cause the rod pad to be moved away from .rod end 23d. The lock pin 27 can then be mounted in another opening (not shown) in the rod 23 and extend through an opening in the stud 26 to again lock the stud 26 and rod pad 24 against rotation. The rod pad is then again mounted with the rail 10 by means of bolt 25.
ln this manner, the effective length of the rod 23 and thus the effective distance d between the extended rails 10 and 11 is increased so that the shoring apparatus can be utilized in ditches of at least greater width. It should be understood that any suitable materials can be utilized in this invention, including synthetic materials as 'well as aluminum and other metals.
The foregoing disclosure and description of the invention are illustrative and explanatory thereof, and various changes in the size, shape, and materials as well as in the details of the illustrated construction may be made Without departing from the spirit of the invention.
1. A hydraulically actuated shoring device, comprising:
a pair of oppositely positioned trench rails. adapted for placement against the sides of a trench or other excavation;
hydraulic jack means connected to said trench rails for moving said rails to an extended position in which said rails support the sides of a trench or other excavation;
said hydraulic jack means including a hydraulic cylinder having a piston slidably mounted therein, said piston having arod attached thereto whereby said piston and said rod are movable between retracted and extended positions as determined by the exit and entry, respectively, of hydraulic fluid under pressure;
cylinder pivot means pivotally connecting said cylinder to one of said trench rails and rod pivot means pivotally connecting said rod to said oppositely positioned trench rail;
protective sleeve means mounted over said cylinder and rod in order to protect both said cylinder and said rod from damage, said protective sleeve means being retractable and extendable with said hydraulic jack means and further including a first sleeve attached to said rod pivot means and extending into slidable engagement with said hydraulic cylinder, said cylinder being provided with protection when said jack means is in said retracted position and said rod being provided with protection in said extended position;
first seal means positioned between said first sleeve and said cylinder to prevent the passage or fluid, dirt or debris therebetween;
a second sleeve attached to said cylinder pivot means and mounted over said cylinder and extended into slidable engagement with said first sleeve; and
second seal means positioned between said first sleeve and said second sleeve to prevent the passage of fluid, dirt or debris therebetween in order to protect said cylinder with said jack means in said extended position.
2. The structure set forth in claim 1, including:
said rod being hollow and threaded on the inside wall thereof at both ends thereof;
said rod pivot means including a force block pivotally mounted with one of said oppositely positioned trench rails, said force block having a threaded bolt extending therefrom in threaded engagement with the inside wall of one end of said rod; and
said piston having a shaft mounted therewith, said shaft including a threaded portion extending into threaded engagement with the other threaded end of said rod whereby the effective length of said cylinder piston and rod combination in said extended position is adjustable.
3. A hydraulically actuated shoring device, comprisa pair of oppositely positioned trench rails adapted for placement against the sides of a trench or other excavation;
hydraulic jack means connected to said trench rails for moving said rails to an extended position in which said rails support the sides of a trench or other excavation;
said hydraulic jack means including a hydraulic cylinder having a piston slidably mounted therein, said piston having a rod attached thereto whereby said piston and said rod are movable between retracted and extended positions as determined by the exit and entry, respectively, of hydraulic fluid under pressure;
cylinder pivot means pivotally connecting said cylinder to one of said trench rails and rod pivot means pivotally connecting said rod to said oppositely positioned trench rail; and
protective sleeve means mounted over said cylinder and rod in order to protect both said cylinder and said rod from damage, said protective sleeve means being retractable and extendable with said hydraulicjack means and including a spiraled, telescoping sleeve mounted over said cylinder and rod and extending between said cylinder and rod pivot means.
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|International Classification||F16J10/02, E21D15/00, E02D17/06, E02D17/08, F16J10/00, E21D15/15|
|Cooperative Classification||F16J10/02, E21D15/15, E02D17/083|
|European Classification||F16J10/02, E02D17/08B, E21D15/15|