Abstract:
A jacking system is disclosed in which a hydraulic jack, having a raisable piston, is used, in combination with a jack stand having a raisable support column, to raise a load. In a preferred embodiment, the support column has two components that may telescope into each other and that may be held in fixed position by two ratchet mechanisms. The jack stand is configured so that, when the hydraulic jack is positioned alongside the jack stand, the piston of the hydraulic jack is able to interact with and raise the support column along with the load.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS  
       [0001]     This application is a continuation-in-part of application Ser. No. 11/286,788, filed Nov. 23, 2005. This application claims the benefit of that application and incorporates it herein by reference. 
     
    
     DEFINITIONS  
       [0002]     The words “comprising,” “having,” “containing,” and “including,” and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items. “Rectangular” includes square.  
       BACKGROUND OF THE INVENTION  
       [0003]     Hydraulic jacks are used to raise many types of loads above ground level such as, for example, automobiles. If the jack remains in place after elevating a load, over time due to leakage of hydraulic fluid, the jack gradually lowers the load. The best practice is to use a jack stand placed under the load to maintain the load elevated and remove the jack once the jack stand is in place.  
         [0004]     A problem occurs in connection with lifting automotive vehicles having a uni-body frame that frequently is bent when the jack is improperly positioned beneath the vehicle. Moreover, even if the jack is placed properly beneath the frame at a position that avoids bending the frame, the jack stand is often placed beneath the frame at an improper position, resulting in the frame bending under the weight of the vehicle when the jack in lowered. Placing the jack stand next to the elevated jack is no guarantee that it is correctly position to avoid bending the frame when the jack is lowered.  
       SUMMARY OF THE INVENTION  
       [0005]     This invention has one or more features as discussed subsequently herein. After reading the following section entitled “DETAILED DESCRIPTION OF SOME EMBODIMENTS OF THIS INVENTION,” one will understand how the features of this invention provide its benefits. The benefits of this invention include, but are not limited to, providing: (a) a jack stand and method that enables the jack stand to be precisely located with respect to an automotive vehicle frame so the frame does not bend under the weight of the vehicle when the jack in lowered, (b) a jack stand enabling a plurality of such stands to be stacked one upon another, (c) an especially configured jack stand facilitating its manufacture from metallic sheet material using conventional metal punching, bending and welding techniques, (d) a jack stand that enables several stand to be stacked one upon the other, (e) a jack stand that may be folded to reduce its size for storage, and (f) a jack stand that may be inserted into a small space beneath an automobile or other load.  
         [0006]     Without limiting the scope of this invention as expressed by the claims that follow, some, but not necessarily all, of its features are:  
         [0007]     One, this invention includes the combination of a jack stand and jack where the jack stand has a moveable, elongated column that is elevated as the jack is elevated. A vertically oriented, compact hydraulic jack may be used. The column is vertically oriented and moveable between a plurality of different elevated positions. The column may have an overhanging member and the stand may have a platform beneath the overhanging member. The jack is placed on the platform and positioned to elevate the column as the jack is elevated.  
         [0008]     Two, the spatial relationship between the column in a completely lowered position and the vertical height of the jack with its piston in a completely lowered position are another feature of this invention. Under these conditions the underside of the overhanging member of the column is above a top side of the platform a predetermined distance substantially equal to the vertical height of the jack with its piston in a completely lowered position. Thus, a head end of the jack&#39;s piston engages this underside, simultaneously raising the column as the jack is elevated. When the pin element is in place holding the jack in a selected elevated position, the jack may be lowered and removed from the platform.  
         [0009]     Three, the support column is held in a selected one of plurality of different elevated positions after being elevated by the hydraulic jack and upon removal of the hydraulic jack from the platform. Different means may be used to hold the raised column in a selected elevated position. One means is that the support column may include a series of pairs of aligned, opposed openings spaced apart along the support column and a removable pin element is inserted though opposed opening when the selected elevated position is attained. Another means is a ratchet mechanism that holds the support column in a selected one of plurality of different elevated positions.  
         [0010]     Four, the column may be detachable and may have a substantially rectangular shape. The column may have at the upper end a locator member with a longitudinal centerline of the stand intersecting a center of the locator member. The locator member may be substantially at a right angle to both the column and a plate member forming the overhanging member and the plate member may be at a right to the column. The locator member may have a central element with opposed ends and a pair of opposed outwardly and upwardly extending flange members, each one connected to one of the ends of the central element.  
         [0011]     Five, the stand may comprise a base and a receptacle. The base has one or more of the following characteristics. It may have a substantially pyramid configuration. It may include at or near a bottom end a jack platform and at a top end the receptacle, which may be hollow and have an open upper end. It may have a longitudinal centerline and the receptacle is oriented lengthwise along the centerline. It may have a hollow interior and a partially open side providing access to the interior, enabling the jack to be seated on the platform with the jack at least partially positioned within the interior and its piston member directly under the overhanging member of the column. It may comprise a pair of sections, with the sections being moveable relative to each other to increase and decrease the height of the base. These sections may be substantially mirror images of each other and they may be attached at upper ends thereof to pivot. Bracing structure extending between lower ends of the sections may be used to increase the rigidity of the base.  
         [0012]     Six, the receptacle may be fixedly attached to the base of the jack stand or it may be a separate detachable member. The receptacle may have dimensions substantially the same as the dimensions of the column to enable the lower end of the column to be inserted into the open upper end of the receptacle. For example, the receptacle and the column may each be of substantially the same rectangular in cross-sectional configuration. The receptacle may include a pair of aligned, opposed openings that enable the removable pin element to be inserted into one opening in the receptacle and through the openings in one pair of the series in the column aligned with the openings in the receptacle and through the other opening in the receptacle. With the pin element so inserted, it maintains the column in a selected elevated position.  
         [0013]     Seven, in yet a further embodiment of the invention, the support column may include an elongate first rod, and an elongate second rod. The first rod is moveable in a direction parallel with the second rod. The plate member is attached to the first rod and positioned substantially at a right angle to the first rod at an upper end of the first rod. A base is provided including an open upper end configured to receive the support column. The support column is moveable along the first axis while received within the open upper end of the base, and the jack stand is configured to be activated by a hydraulic jack having a piston, the piston having a second elongate axis, and wherein the jack stand is positioned for use in relation to the hydraulic jack with the piston in contact with the plate member such that the second axis is not coaxial with the first axis. When the piston is raised to elevate a load, the support column is raised.  
         [0014]     In a further aspect, the support column is configured to be held in a selected one of plurality of different elevated positions in relation to the base after the support column is raised by the hydraulic jack. A first ratchet mechanism may be used for holding the support column in a selected one of a plurality of different elevated positions in relation to the base. In further detail, the first ratchet mechanism may be configured to hold the second rod in relation to the base. In yet further detail, the first rod may be configured to be held in a selected one of a plurality of different elevated positions in relation to the second rod after the support column is raised by the hydraulic jack, where the holding may be performed by a second ratchet mechanism.  
         [0015]     Eight, the invention may be an entire jacking system comprising a jack stand as described above, in combination with a hydraulic jack including a piston that has an outer sleeve and an inner sleeve, the inner sleeve being slidable within the outer sleeve to provide a telescoping piston. In this system, the features of the jack stand as described above are included.  
         [0016]     Finally, a method of lifting a load is included in this invention that comprises: 
        (a) positioning beneath the load at a predetermined location relative to the load a jack stand including a vertically oriented column having a first elongate axis, the column being moveable between a plurality of different elevated positions and having an overhanging member;     (b) positioning a vertically oriented, compact hydraulic jack having a piston member next to the stand beneath the overhanging member, the piston member having a second elongate axis, wherein the second axis is not coaxial with the first axis;     (c) actuating the hydraulic jack to elevate the piston member along the second axis so that the piston member engages an underside of the overhanging member and elevates the column to bring an upper end of the column into contact with the load; and     (d) holding the column in a selected elevated vertical position.        
 
         [0021]     These and other advantages of the invention will become more apparent from the following detailed description thereof and the accompanying exemplary drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]     Some embodiments of this invention, illustrating all its features, will now be discussed in detail. These embodiments depict the novel and non-obvious jack stand and jack combination and method of this invention as shown in the accompanying drawing, which is for illustrative purposes only. This drawing includes the following figures (Figs.), with like numerals indicating like parts:  
         [0023]      FIG. 1  is an exploded perspective view, with a section of the platform broken away, of the jack stand and jack combination of one embodiment of this invention.  
         [0024]      FIG. 2  is a perspective view of the jack stand shown in  FIG. 1 , with a section of the plate member broken away and partially assembled with its support column aligned to be inserted into an upper open end the stand&#39;s receptacle, and the jack next to the stand&#39;s platform.  
         [0025]      FIG. 3  is a perspective view of the jack stand shown in  FIG. 1 , completely assembled with its support column inserted into the upper open end of the stand&#39;s receptacle and in a completely raised position, and the jack next to the stand&#39;s platform.  
         [0026]      FIG. 4  is a perspective view of the jack stand shown in of  FIG. 1 , completely assembled with its support column inserted into the upper open end of the stand&#39;s receptacle and in a completely lowered position, and the jack next to the stand&#39;s platform.  
         [0027]      FIG. 5  is a front perspective view of the jack stand shown in  FIG. 1  with the jack on the platform and its piston raised to elevate the support column.  
         [0028]      FIG. 6  is a rear perspective view of the jack stand and elevated jack as shown in  FIG. 5 .  
         [0029]      FIG. 7  is a perspective view of a pair of jack stands shown in  FIG. 1  stacked together, with a section of the one of the receptacles broken away.  
         [0030]      FIG. 8  is an exploded perspective view of the jack stand and jack combination of an other embodiment of this invention illustrating a jack stand comprising a pair of sections attached to pivot and lower or raise the height of the stand.  
         [0031]      FIG. 8A  is a perspective view of the receptacle used in the jack stand shown in  FIG. 8  looking at the rear of the receptacle.  
         [0032]      FIGS. 9 through 12  depict the jack stand and jack combination shown in  FIG. 8  in different positions where:  
         [0033]      FIG. 9  is a perspective view of the jack stand shown in  FIG. 8  at a lower position with its sections spread apart and their lower ends attached by a pair of braces.  
         [0034]      FIG. 10  is a perspective view of the jack stand shown in  FIG. 8  at a higher elevation than that shown in  FIG. 9  and lower ends of the sections not separated.  
         [0035]      FIG. 11  is a perspective view of the jack stand shown in  FIG. 8  with its column elevated the same as shown in  FIG. 10  and the sections of the stand moved into a position intermediate that shown in  FIGS. 10 and 12 .  
         [0036]      FIG. 12  is a perspective view of the jack stand shown in  FIG. 8  with its column elevated the same as shown in  FIGS. 10 and 11  and the sections of the stand moved into a position of maximum separation.  
         [0037]      FIGS. 13 through 16  depict yet another embodiment of the jack stand and jack combination of this invention where:  
         [0038]      FIG. 13  is a perspective view looking a rear side of a jack stand and jack combination utilizing a ratchet mechanism to raise and lower the column of the jack stand.  
         [0039]      FIG. 14  is a perspective view looking a rear side of the jack stand and jack combination shown in  FIG. 13 .  
         [0040]      FIG. 15  is a side view of the jack stand and jack combination shown in  FIG. 13 .  
         [0041]      FIG. 16  is a fragmentary view showing the ratchet mechanism of the jack stand and jack combination shown in  FIG. 13 .  
         [0042]      FIGS. 17 through 19  depict yet another embodiment of a jacking system of this invention where:  
         [0043]      FIG. 17  is a perspective view of the jacking system of the present embodiment in a retracted condition.  
         [0044]      FIG. 18  is a perspective view of the jacking system of  FIG. 17 , shown in an elevated condition.  
         [0045]      FIG. 19  is a sectional view of the jacking system shown in  FIG. 18  in elevated condition. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0046]     This invention comprises a unique jack stand used with a conventional hydraulic jack, for example, a bottle jack  12 . There are several embodiments of the jack stand illustrated, namely, the jack stand  10  shown in  FIGS. 1 through 7 , the jack stand  10   a  shown in  FIGS. 8 through 12 , and the jack stand  10   b  shown in  FIGS. 13 through 16 . In the embodiments illustrated, each stand includes a elongated support column  16 , a plate member  28  substantially at a right angle to the column at an upper end of the column, and a base  11  including at or near a bottom end a jack platform  18  and at a top end a hollow receptacle  13  having an open upper end into which the support column is inserted during use. The base  11  may have a rigid, one piece a substantially pyramid configuration as illustrated in the embodiments shown in  FIGS. 1 through 7  and  FIGS. 13 through 16 . Or, the base  11  may have a foldable, two-piece substantially pyramid configuration as illustrated in the embodiment shown in  FIGS. 8 through 12 .  
         [0047]     The support column  16  is moveable lengthwise while positioned within the receptacle  13 , and the hydraulic jack  12  is adapted to sit on the platform  18 . The hydraulic jack  12  includes a piston  14  having an upper end that is beneath the plate member  28  when the jack  12  is sitting on the platform  18 . The piston  14  elevates the column  16  as the piston  14  is raised by manually actuating the jack  12 . Upon removal of the hydraulic jack  12  from the platform  14 , the support column  16  is held in a selected one of plurality of different elevated positions. This may be accomplished by means of a pin element  22  used in the embodiments depicted in  FIGS. 1 through 7  and  FIGS. 8 through 12 , or a ratchet mechanism  60  used in the embodiment depicted in  FIGS. 13 through 16 .  
         [0048]    
       FIGS. 1 through 7 
     
         [0049]     As illustrated in  FIG. 1 , the jack stand  10  of this invention is used with the bottle jack  12 . The bottle jack  12  is compact and normally operated in a vertical orientation. Its hydraulically actuated piston  14  elevates a load in response to operating its piston raising and lowering mechanism  12   a  by manually manipulating its detachable handle  17  shown in dotted lines in  FIG. 1 . A head end  14   a  of the piston  14  has a knurled surface.  
         [0050]     The stand  10  includes the base  11 , the receptacle  13 , the elongated support column  16  received within the receptacle, and the jack platform  18  for supporting the bottle jack  12  in an upright, vertical orientation. The receptacle  13  has a substantially rectangular cross-sectional shape formed by opposed front side  13   a  and back side  13   b  ( FIG. 6 ), and a right hand side  13   c  as viewed in  FIG. 6  and a left hand side  13   d  as viewed in  FIG. 5 . It includes an opening  20   a  in the right side  13   c  and an opening  20   b  ( FIG. 1 ) in the left side  13   d  that are aligned and opposed to each other. The removable pin element  22 , which has a grip ring  22   a  at one end, holds the support column  16  in a selected elevated position.  
         [0051]     The support column  16  is detachable and has a substantially rectangular cross-sectional shape formed by opposed front side  16   a  and back side  16   b  ( FIG. 6 ), and a right hand side  16   c  as best viewed in  FIG. 6  and a left hand side  16   d  as best viewed in  FIG. 2 . There are openings  25   a ,  25   b , and  25   c  equally spaced lengthwise along the right hand side  16   c  and openings  26   a ,  26   b , and  26   c  equally spaced lengthwise along the left hand side  16   d . This arrangement provides a series of pairs  25   a - 26   a ,  25   b - 26   b , and  25   c - 26   c  of aligned, opposed openings spaced apart along the opposed sides  16   c  and  16   d  of the support column  16  between an upper end E 1  and a lower end E 2  of the column. The cross-section dimensions of the receptacle  13  and the column  16  are substantially the same, with the cross-section dimensions of the column being slightly less. This enables the lower end E 2  of the column  16  to be inserted into an open upper end E 3  ( FIGS. 1 and 2 ) of the receptacle  13  in a male-female mating relationship.  
         [0052]     The load supporting plate member  28  is attached to the column  16  in a manner to overhang the platform  18 . This plate member  28  has an upper substantially flat top  28   a  with a flat underside  29  ( FIG. 2 ) and downwardly extending sides  28   b ,  28   c ,  28   d , and  28   e  that are substantially at a right angle to the flat top and underside. The column&#39;s rear side  28   e  is welded to the front side  16   a  of the column  16  at the upper end E 1  substantially at a right angle to the column. The column  16  has at the upper end E 1  a locator member  30  welded to this end. The locator member  30  is at substantially a right angle to the plate member  28  and is substantially concave or U-shape to better engage a frame of an automotive vehicle or other object being lifted. A longitudinal centerline C ( FIG. 2 ) of the stand  10  intersects the center C 1  of the locator member  30  when the column  16  is inserted into the receptacle  13 . As best shown in  FIG. 5 , the locator member  30  has a central element  30   a  with opposed ends E 4  and E 5  and a pair of opposed outwardly and upwardly extending flange members  30   b  and  30   c . Each flange member is integral with the ends of the central element  30   a.    
         [0053]     The base  11  has a substantially pyramid configuration and a longitudinal centerline coincident with the centerline C that intersects a truncated apex end E 6 . Four flat inwardly slanting, substantially triangular configured sides  11   a ,  11   b ,  11   c  ( FIG. 6 ), and  11   d  ( FIG. 6 ) form a hollow interior  32 . The receptacle  13  is welded to the apex end E 6  and oriented lengthwise along the centerline C and centrally positioned with respect to the centerline. The opposed sides  11   a  and  11   c  each have central triangular cut-a-way  34   a  and  34   c , providing, respectively, lower wall sections  36   a  and  36   b  ( FIG. 6 ). As discussed subsequently in greater detail, the central triangular cut-a-ways  34   a  and  34   c  provide access to the interior  32 . Substantially inverted V-shaped cut-a-ways  39   a  and  39   b  are respectively in the opposed triangular configured sides  11   b  and  11   d  ( FIG. 6 ), and substantially inverted U-shaped cut-a-ways  41   a  and  41   b  ( FIG. 6 ) are respectively in the opposed triangular configured sides  11   a  and  11   c . These cut-a-ways  39   a  and  39   b  and  41   a  and  41   b  form foot elements F 1 , F 2 , F 3 , and F 4  ( FIG. 6 ) at the bottom corners of the base  11 .  
         [0054]     The jack platform  18  is at or near a bottom end E 7  of the base and it includes a flat top side  18   a , a right side  18   b  as viewed in  FIG. 6 , a left side  18   c , a front side  18   d , and an open rear side  18   e  ( FIG. 6 ). The sides  18   b ,  18   c , and  18   d  are substantially at a right angle to the flat top side  18   a . A pair of upwardly and inwardly slanted aligned slots  44   a  ( FIG. 1 ) and  44   b  respectively in the sides  18   b  and  18   c  enable the jack platform  18  to be mounted to the lower wall sections  36   a  or  36   b  ( FIG. 6 ) of the base  11 , as the case may be. An upper edge E 8  of the lower wall sections  36   a  or  36   b , as the case may be, slides into the aligned slots  44   a  and  44   b  to position the platform  18  so its flat top side  18   a  is substantially horizontal when the stand is resting on its foot elements F 1 , F 2 , F 3 , and F 4  to orient the receptacle  13  substantially vertical. The platform  18  may be welded in place. Alternately, the platform  18  is not fixed in place so that it may be detached.  
         [0055]     This configuration of the base  11  and receptacle  13  is essentially symmetrical about the centerline C. Consequently, even with their platforms attached, a plurality of the stands, with their columns and pin elements removed, may be stacked together as shown in  FIG. 7 . For example, a second essentially identical jack stand  10 ′ is placed on top of the stand  10 . The receptacle  13  of the stand  10  abuts an open lower end E 9  of the receptacle  13 ′ of the stand  10 ′ and the platform  18  is directly beneath the platform  18 ′ of the stand  10 ′. Thus, the stands  10  and  10 ′ are nested together with the platforms  18  and  18 ′ aligned. This stacking feature saves space, reducing storage and packaging costs.  
         [0056]     The bottle hydraulic jack  12  is adapted to sit on the flat top side  18   a  of the platform  18  in an upright, substantially vertical orientation. The jack stand  10  is initially placed, for example, beneath a frame of an automotive vehicle and positioned with respect to the frame so that the locator member  30  will contact a vehicle&#39;s frame at a precise location that avoids any damage to the frame when the column  16  of the jack stand is elevated to support the vehicle. As shown in  FIG. 4 , with the column  16  of the jack stand  10  completely lowered and the piston member  14  of the jack  12  in a completely lowered position, the distance d 1  between the underside  29  ( FIG. 2 ) of the plate member  28  and the top side  18   a  of the platform  18  is essentially equal to the distance d 2  between the piston head end  14   a  and the bottom of the jack  12 . In other words, with the column  16  completely lowered, the distance d 1  is substantially equal to the height of the vertically oriented jack  12  with its piston  14  completely lowered.  
         [0057]     The jack  12  while on the platform  18  is at least partially received within the hollow interior  32  and is at or near the centerline C. Thus, with the jack  12  so positioned on the platform  18 , the piston head end  14   a  is directly under and adjacent to the underside  29  of the plate member  28 . The piston head end  14   a  engages the underside  29  of the plate member  28  as the piston  14  is elevated in response to the actuation of the piston raising and lowering mechanism  12 . The upward vertical movement of the piston  14  raises the column  16 , pressing the locator member  30  against the desired precise location along the frame to avoid damaging the frame.  
         [0058]     At a selected elevation, the user manually inserts the pin element  22  into aligned openings in the column  16  and the receptacle  13 . When the opening  20   a  and  20   b  in the receptacle  13  are aligned with the pair of opening  25   a - 26   a  and the pin element  22  is inserted into these four aligned openings, the column  16  is at its lowest elevation. When the opening  20   a  and  20   b  are aligned with the pair of opening  25   c - 26   c  and the pin element  22  is inserted into these four aligned openings, the column  16  is at its highest elevation as shown in  FIGS. 5 and 6 . When the opening  20   a  and  20   b  are aligned with the pair of opening  25   b - 26   b  and the pin element  22  is inserted into these four aligned openings, the column  16  is at an intermediate elevation between the highest and lowest elevations.  
         [0059]     With the column  16  so elevated, the jack&#39;s piston  14  is lowered by the user actuating the piston raising and lowering mechanism  12   a . The jack  12  may then be removed from the platform  18 . Because the locator member  30  contacts the precise location along the frame that avoids bending or otherwise damaging the frame, removal of the jack has no adverse consequences. Simultaneously raising the column  16  as the jack  12  is elevated thus moves the locator member  30  into contact with the precise location along the frame. This solves the problem associate with the two step procedure of first using a jack and then, while the jack is raised and supporting a load, placing a jack stand next to the raised jack to support the load. When the user desires to remove the stand  10 , the jack  12  is again placed on the platform and elevated to support the load upon removal of the pin element  22 . With the pin element  22  removed the user actuates the piston raising and lowering mechanism  12   a  to lower the column  16  to the position shown in  FIG. 4 .  
         [0060]    
       FIGS. 8 through 12 
     
         [0061]     In the embodiment shown in  FIGS. 8 through 12 , the jack stand  10   a  is of similar pyramid shape to that of the stand  10 , but its base  11   a  is bifurcated into two sections A and B, which are substantially mirror images of each other. The receptacle  13  is used with this stand  10   a  but is detachably connected by bolts  42  and  43  to the upper end E 10  of the stand  10   a . The receptacle  13  includes aligned pairs of orifices  40   a  ( FIG. 8 ) and  40   b  ( FIG. 8A ) and  41   a  ( FIG. 8 ) and  41   b  ( FIG. 8A ) beneath the aligned opening  20   a  ( FIG. 8A ) and  20   b  ( FIG. 8 ). The bolt  42  extends through the aligned orifices  40   a  and  40   b  and the bolt  43  extends through the aligned orifices  41   a  and  41   b . Nuts  44  and  45  respectively attached to the ends of the bolts  42  and  43  secure the sections A and B to the receptacle  13  in a manner allowing these sections to pivot about the bolts. The lower ends E 11   a  and E 11   b  of the sections A and B are thus moveable relative to each other to increase and decrease the height of the stand  10   a . These ends E 11   a  and E 11   b  have apertures  50  ( FIG. 8 ) therein that enable removable pins  51  to detachably connect a pair of braces  46  and  48  to these ends. As shown in  FIGS. 9 through 12 , the braces  46  and  48  are on opposite sides of the stand  10   a  and they are selectively positioned to control the distance between the lower ends E 11   a  and E 11   b  to either increase or decrease the height of the base  11   a . Each of these braces  46  and  48  has at its one end a hole  46   a  and  48   a , as the case may be, and at its opposed end a series  46   b  and  48   b , as the case may be, of aligned equally spaced apart holes. Pins  51  ( FIG. 8 ) are used to connect the braces  46  and  48  to the lower ends E 11   a  and E 11   b  of the sections A and B.  
         [0062]    
       FIGS. 13 through 16 
     
         [0063]     As depicted in  FIGS. 13 through 16 , the column  16  of the jack stand  10   b  does not have the openings  26   a ,  26   b , and  26   c  therein that interact with the pin  22  to hold the raised column in a selected elevated position. Instead, the ratchet mechanism  60  holds the support column  16  in a selected one of plurality of different elevated positions.  
         [0064]     This ratchet mechanism  60  includes a series of teeth  66  along an outer edge  19  of the column  16  that engage a pawl  62  mounted on the receptacle  13  to rotate. A manually operated handle  64  connected to the pawl  62  controls the direction of rotation of the pawl. With the handle  64  in the position shown in solid lines, the pawl  62  may only rotate in a counter-clockwise direction as shown in  FIG. 16 . Thus, as the piston  14  of the jack  12  is raised, the column  16  is lifted with the pawl  62  passing over the teeth until the desired elevation is attained. At this desired elevation, the pawl  62  moves between a pair of adjacent teeth  66   a  and  66   b  ( FIG. 16 ) and engages the upper tooth  66   a  of these adjacent teeth, holding the column  16  in the selected elevated position. The jack  12  is now removed from the platform and the column  16  being held by the pawl  62  remains in the selected elevated position until lowered.  
         [0065]     When the column  16  is to be lowered, the jack  12  is again placed on the jack platform  18 , and the handle  64  is manually moved in the position shown in dotted lines in  FIG. 16 . This enables the pawl  62  to rotated in a clockwise direction as shown in  FIG. 16 . With the head end  14   a  of the piston  14  engaging the underside of the plate member  28  and the handle  64  in the dotted line position, the pawl  62  moves past the teeth  66  along the descending column  16  as it is lowered simultaneously with the piston by actuating the piston raising and lowering mechanism  12   a.    
         [0066]      FIGS. 17 through 19 .  
         [0067]     As depicted in  FIGS. 17 through 19 , an embodiment is disclosed in which the column  16  (passing through the receptacle  13 ) includes an additional column portion  16 ′ (or, first rod) configured to slide within the column  16  (or, second rod), thus providing a telescoping column. In another aspect, the hydraulic jack may also have an additional piston portion  14 ′ configured to slide within the piston  14 , thus providing a telescoping piston which is known in the field of hydraulic jacks. These telescoping features have the advantage of permitting the jacking system, which includes both the hydraulic jack and the jack stand, to be given a much shorter vertical height than the previous embodiments—and yet be capable of elevating loads by a distance comparable with the previous embodiments. This advantage is important in situations where the load to be lifted is close to the ground, but must be lifted to a height sufficient for a person to crawl underneath. Thus, if a large SUV is to be elevated, a jacking system of the previous embodiments may be suitable, but if a sedan automobile with an undercarriage close to the ground is to be lifted, it may be necessary to use the present embodiment to achieve an adequate clearance space after lifting.  
         [0068]     In one aspect of this embodiment, two separate ratchet mechanisms may be used. A first ratchet mechanism  60  is similar to that used in previous embodiments for holding the column  16  in fixed relation to the base  11 . The first ratchet mechanism includes teeth  66  on the column  16 , a lever  64  for setting the direction of the ratchet movement, and a pawl  62  for insertion between the teeth to hold the column  16  in fixed relation to the base  11 . A second ratchet mechanism  60 ′ is provided to permit the additional column portion  16 ′ to slide to selectable positions in relation to the column  16  itself. The second ratchet mechanism includes a second set of teeth  66 ′ on the additional column portion  16 ′, a second lever  64 ′ for setting the direction of relative movement between the two column portions  16 ,  16 ′ and a second pawl  62 ′ ( FIG. 19 ) for insertion between the second set of teeth  66 ′ to hold the additional column portion  16 ′ in relation to the lower column  16 .  
         [0069]     It will be appreciated that elevating the telescoping piston into contact with the underside of the plate member  28 , the upper side of which may be in contact with a load, and then further upwards to lift the load, will cause the column  16  and additional column portion  16 ′ to be raised also. An upward load will be applied, via the plate member  28 , to the additional column portion  16 ′ (first rod), which will in turn pull upwardly on the column  16  (second rd). As the column  16  and the additional column portion  16 ′ are raised, the two pawls  62 ,  62 ′ will fall in between the sets of teeth  66 ,  66 ′ to form a barrier to the retraction of the jack stand. It will be appreciated that the rate of lifting the column  16  and additional column portion  16 ′ in relation to each other will depend on the relative friction and drag applied by the two ratchet mechanisms, but that ultimately the column  16  and additional column portion  16 ′ are extendable to their full extent without manual intervention with the ratchet mechanisms  60  and  60 ′. Thus, when the operator is satisfied with the elevation of the load, he may simply terminate actuating the hydraulic jack. If the hydraulic jack slowly dissipates internal hydraulic pressure to allow the upper tip of the piston to fall slightly, the load will transfer to the elevated jack stand  10  which is mechanically held in fixed elevated position by the column  16  and additional column portion  16 ′ which in turn are held in fixed position in relation to the base  11  by the two ratchet mechanisms  60 , and  60 ′. Finally, when the user wishes to lower the load, the hydraulic jack  12  must be activated to assume the load if pressure has become dissipated, the direction of the ratchet mechanisms reversed by setting the handles  64 ,  64 ′, and the hydraulic jack slowly lowered by manually releasing hydraulic pressure.  
         [0070]     In the present embodiment, it may be convenient to mount the jack stand and the hydraulic jack  12  on a stand  18  configured to hold the jack stand and hydraulic jack in fixed relation to each other, with the axis C 1  of the column and the elongate axis of the piston being not co-axial. This aspect conveniently permits the piston to engage with the overhanging plate member  28  of the jack stand when the piston is elevated.  
         [0071]     The above presents a description of the best mode contemplated of carrying out the present invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains to make and use this invention. This invention is, however, susceptible to modifications and alternate constructions from that discussed above which are fully equivalent. Consequently, it is not the intention to limit this invention to the particular embodiment disclosed. On the contrary, the intention is to cover all modifications and alternate constructions coming within the spirit and scope of the invention as generally expressed by the following claims, which particularly point out and distinctly claim the subject matter of the invention: