Abstract:
A hydraulic jack includes an oil cylinder, an oil tank, and an oil storage barrel. The oil storage barrel includes a front portion and a back portion which are opposite to each other; an oil outlet of the oil cylinder is connected with an oil inlet at the front portion of the oil storage barrel by means of an oil inlet pipe; and an oil inlet of the oil tank is connected with an oil outlet at the front portion of the oil storage barrel by means of an oil outlet pipe, the oil inlet pipe and the oil outlet pipe are provided with switching valves for alternatively turning on the oil inlet pipe and the oil outlet pipe. A partition plate that is capable of moving along a barrel wall and an elastic telescoping member are provided inside the oil storage barrel.

Description:
TECHNICAL FIELD 
       [0001]    An embodiment of the present disclosure relates to a hydraulic jack. 
       BACKGROUND 
       [0002]    A jack is a rigid jacking member, i.e., a light hoisting equipment that lifts weights within its capability range via a top bracket. Common jack includes mechanical jack and hydraulic jack. 
       SUMMARY 
       [0003]    An embodiment of the present disclosure provides a hydraulic jack, comprising an oil cylinder, an oil reservoir and an oil storage tank, wherein the oil storage tank includes a front part and a back part opposite to each other, an oil outlet of the oil cylinder is connected to an oil inlet at the front part of the oil storage tank via an oil inlet pipe, an oil inlet of the oil reservoir is connected to an oil outlet at the front part of the oil storage tank via an oil outlet pipe, and a switch valve is arranged on the oil inlet pipe and the oil outlet pipe and configured for turning on one of the oil inlet pipe and the oil outlet pipe while turning off the other, a clapboard and an elastic component are arranged in the oil storage tank, the clapboard is movable between the front part and the back part of the oil storage tank along a wall of the oil storage tank, inner space of the oil storage tank is divided into a front space and a back space located on two opposite sides of the clapboard, the front space is communicated with the oil inlet pipe and the oil outlet pipe, the front space and the back space are not communicated with each other, and the clapboard is connected to the back part of the oil storage tank via the elastic component located in the back space. 
         [0004]    In an example, the oil inlet pipe comprises a first oil inlet pipe and a second oil inlet pipe, the oil outlet pipe comprises a first oil outlet pipe and a second oil outlet pipe, an end of the first oil inlet pipe is connected to the oil inlet at the front part of the oil storage tank, an end of the first oil outlet pipe is connected to the oil outlet at the front part of the oil storage tank, an end of the second oil inlet pipe is connected to the oil outlet of the oil cylinder, and an end of the second oil outlet is connected to the oil inlet of the oil reservoir; the switch valve is located between the first oil inlet pipe and the second oil inlet pipe, and between the first oil outlet pipe and the second oil outlet pipe. 
         [0005]    In an example, the switch valve comprises a rotatable component, and the first oil inlet pipe, the first oil outlet pipe, the second oil inlet pipe and the second oil outlet pipe are configured to fit the rotatable component; the rotatable component is provided with a first hole and a second hole passing through the rotatable component, and a straight line extending direction of the first hole and a straight line extending direction of the second hole are neither parallel to nor intersected with each other; in a case where the first oil inlet pipe and the second oil inlet pipe are communicated via the first hole, the first oil outlet pipe and the second oil outlet pipe are not communicated, and in a case where the first oil outlet pipe and the second oil outlet pipe are communicated via the second hole, the first oil inlet pipe and the second oil inlet pipe are not communicated. 
         [0006]    In an example, the extending direction of the first hole and the extending direction of the second hole are perpendicular to each other. 
         [0007]    In an example, a side surface of the rotatable component is a cylindrical surface, and the first oil inlet pipe, the first oil outlet pipe, the second oil inlet pipe and the second oil outlet pipe fit the side surface of the rotatable component. 
         [0008]    In an example, at least one bottom surface of the rotatable component is provided with a handle. 
         [0009]    In an example, the elastic component is a spring, of which one end is connected to the back part of the oil storage tank while the other end is connected to the clapboard. 
         [0010]    In an example, the switch valve further includes a protective body, in which the rotatable component is encapsulated. 
         [0011]    In an example, the hydraulic jack further includes an oil return valve, of which one end is connected to the oil outlet of the oil cylinder while the other end is connected to the oil inlet of the oil reservoir. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    In order to clearly illustrate the technical solution of the embodiments of the disclosure, the drawings of the embodiments or in the related art will be briefly described in the following; it is obvious that the described drawings are only related to some embodiments of the disclosure and thus are not limitative of the disclosure. 
           [0013]      FIG. 1  is a structural schematic diagram of a hydraulic jack in an embodiment of the present disclosure; 
           [0014]      FIG. 2  is a structural schematic diagram of an oil storage tank in the embodiment of the present disclosure; 
           [0015]      FIG. 3  is a structural schematic diagram of an oil inlet pipe, an oil outlet pipe, a switch valve and an oil storage tank in the embodiment of the present disclosure; 
           [0016]      FIG. 4  is a structural schematic diagram of the switch valve in the embodiment of the present disclosure; 
           [0017]      FIG. 5  is a sectional view of the switch valve in the embodiment of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    The technical solutions of the embodiment will be described in a clearly and fully understandable way in connection with the drawings related to the embodiments of the disclosure. It is obvious that the described embodiments are just a part but not all of the embodiments of the disclosure. Based on the described embodiments herein, those skilled in the art can obtain other embodiment(s), without any inventive work, which should be within the scope of the disclosure. 
         [0019]    In a related art, a hydraulic jack is filled with hydraulic oil, and ascending and descending of the hydraulic jack is controlled by a pressure of the hydraulic oil. An oil return valve is arranged in an oil return pipe of the hydraulic jack. When the oil return valve is opened, the hydraulic oil returns to the oil reservoir where hydraulic oil is stored in the hydraulic jack, so that the front part bracket of the hydraulic jack descends. 
         [0020]    The inventors find that the oil return valve of the hydraulic jack in the related art has to be manually controlled by an operator. It is difficult for an operator to control an extent and time of switching the oil return valve, and it is probable that the front part bracket of the hydraulic jack will descend speedily, risking the operator and object placed on the front part bracket. 
         [0021]    An embodiment of the present disclosure provides a hydraulic jack, which can prevent a drop-off of the front part bracket of the hydraulic jack so as to reduce the risk to the operator of the hydraulic jack and the object in the front part bracket. 
         [0022]    Referring to  FIG. 1  and  FIG. 2 , the embodiment of the present disclosure provides a hydraulic jack, including an oil cylinder  10 , an oil reservoir  11  and an oil storage tank  13 . The oil storage tank  13  includes a front part F and a back part B opposite to each other. An oil outlet  101  of the oil cylinder  10  is connected to an oil inlet  131  at the front part F of the oil storage tank  13  via an oil inlet pipe  12 , and an oil inlet  111  of the oil reservoir  11  is connected to an oil outlet  132  at the front part F of the oil storage tank  13  via an oil outlet pipe  14 . A switch valve  15  is arranged on the oil inlet pipe  12  and the oil outlet pipe  14  and configured for turning on one the oil inlet pipe  12  and the oil outlet pipe  14  while turning off the other; a clapboard  16  which is movable along a wall W of the oil storage tank  13  and an elastic component  17  are arranged in the oil storage tank  13 , the elastic component  17  is located between the clapboard  16  and back part B of the oil storage tank  13 . The clapboard  16  is movable between the front part F and the back part B of the oil storage tank  13  along the wall W of the oil storage tank. Inner space of the oil storage tank  13  is communicated with the outside only by, for example, the oil inlet  131  and the oil outlet  132  at the front part F. The inner space of the oil storage tank  13  is divided into a front space FS and a back space BS located on two opposite sides of the clapboard. The front space FS is communicated with the oil inlet pipe  12  and the oil outlet pipe  14 . The front space FS and the back space BS are not communicated with each other. The clapboard  16  is connected to the back part B of the oil storage tank  13  via the elastic component  17  located in the back space BS. 
         [0023]    When the oil inlet pipe  12  is turned on under the control of the switch valve  15 , hydraulic oil enters the oil storage tank  13 ; during the process that the hydraulic oil enters the oil storage tank  13 , the hydraulic oil pushes the clapboard  16  in the oil storage tank  13 , and the clapboard  16  presses the elastic component  17  so that the elastic component  17  generates an elastic force, and finally the oil pressure of the hydraulic oil entered into the oil storage tank  13  is balanced with the elastic force generated by the elastic component  17  and no more hydraulic oil can enter the oil storage tank  13 ; at this moment, the switch valve  15  arranged on the oil inlet pipe  12  controls the oil inlet pipe  12  to shut; afterwards, for example, the oil outlet pipe  14  is turned on under the control of the switch valve  15  arranged on the oil outlet pipe  14 , the elastic component  17  resiles to push the clapboard  16  to press the hydraulic oil in the oil storage tank  13  out of the oil storage tank  13  via the oil outlet pipe  14 , and back to the oil reservoir  11  of the hydraulic jack via the oil outlet pipe  14 , so that the hydraulic oil can be recycled. Because the amount of hydraulic oil balanced to the elastic force of the elastic component  17  is constant, the top bracket of the hydraulic jack is lowered at a slower speed. 
         [0024]    In the hydraulic jack provided by the embodiment of the present disclosure, the oil cylinder  10  and the oil reservoir  11  are connected to the oil storage tank  13  via the oil inlet pipe  12  and the oil outlet pipe  14  respectively; a clapboard  16  movable along the wall and an elastic component  17  located between the clapboard  16  and the back part of the oil storage tank  13  are arranged in the oil storage tank  13 ; and a switch valve  15  for controlling opening and closing of the oil inlet pipe  12  or the oil outlet pipe  14  is arranged on the oil inlet pipe  12  and the oil inlet pipe  14 . The switch valve  15  is operated to turn on the oil inlet pipe  12  so that the hydraulic oil enters into the oil storage tank  13  until the oil pressure of hydraulic oil in the oil storage tank  13  is balanced with the elastic force of the elastic component  17  in the oil storage tank  13 ; or, the switch valve  15  is operated to turn on the oil outlet pipe  14  so that the elastic component  17  in the oil storage tank  13  pushes the clapboard  16  to press the hydraulic oil out of the oil storage tank  13 . Compared with an oil return valve where the extent and the time of switching is controlled manually in the related art, in the hydraulic jack of the embodiment of the present disclosure, the amount of hydraulic oil that enters the oil storage tank  13  which is balanced with the elastic force of the elastic component  17  is constant, so that the top bracket of the hydraulic jack is lowered at a slower speed, which prevents a big drop-off of the top bracket of the hydraulic jack, reducing the risk to the operator of the hydraulic jack and object in the top bracket. 
         [0025]    In a case where multiple hydraulic jacks of the embodiment of the present disclosure are applied to work, the amount of hydraulic oil entering the oil storage tank  13  of each hydraulic jack each time is generally the same, so that when multiple hydraulic jacks are working jointly, the ascending distance of each top bracket of the multiple hydraulic jacks is generally the same, preventing the problem of distance difference of the top brackets of multiple hydraulic jacks caused by manual control over oil return valves in the related art. 
         [0026]    Referring to  FIG. 1  and  FIG. 3  (the oil reservoir  11  or the oil cylinder  10  are not shown in  FIG. 3 ), for example, the oil inlet pipe  12  includes a first oil inlet pipe  18  and a second oil inlet pipe  19 , and the oil outlet pipe  14  includes a first oil outlet pipe  20  and a second oil outlet pipe  21 . One end of the first oil inlet pipe  18  is connected to the oil inlet  131  at the front part of the oil storage tank  13  while the other end thereof is connected airtight to the switch valve  15 ; one end of the first oil outlet pipe  20  is connected to the oil outlet  132  at the front part of the oil storage tank  13  while the other end thereof is connected airtight to the switch valve  15 ; one end of the second oil inlet pipe  19  is connected to the oil outlet  101  of the oil cylinder  10  while the other end thereof is connected airtight to the switch valve  15 ; and one end of the second oil outlet is connected to the oil inlet  111  of the oil reservoir  11  while the other end thereof is connected airtight to the switch valve  15 ; the switch valve  15  configured for turning on one of the oil inlet pipe  12  and the oil outlet pipe  14  while turning off the other is located between the first oil inlet pipe  18  and the second oil inlet pipe  19 , and between the first oil outlet pipe  20  and the second oil outlet pipe  21 . In this case, the expression “turning on the oil inlet pipe  12 ” refers to communicating the first oil inlet pipe  18  and the second oil inlet pipe  19 ; the expression “turning on the oil outlet pipe  14 ” refers to communicating the first oil outlet pipe  20  and the second oil outlet pipe  21 . The expression “the switch valve  15  configured for turning on one of the oil inlet pipe  12  and the oil outlet pipe  14  while turning off the other” refers to that the switch valve  15  is configured for turning off the oil outlet pipe  14  upon turning on the oil inlet pipe  12  on one hand, and turning off the oil inlet pipe  12  upon turning on the oil outlet pipe  14  on the other hand. 
         [0027]    Referring to  FIG. 4  and  FIG. 5 , in order to facilitate the operation of the switch valve  15 , the switch valve  15  includes, for example, a rotatable component  22  placed between the first oil inlet pipe  18  and the second oil inlet pipe  19  and between the first oil outlet pipe  20  and the second oil outlet pipe  21 . A side surface K of the rotatable component  22  is, for example, a cylindrical side surface. For example, the rotatable component  22  is cylinder-shaped. All of the first oil inlet pipe  18 , the first oil outlet pipe  20 , the second oil inlet pipe  19  and the second oil outlet pipe  21  fit the cylinder-shaped side surface K of the rotatable component  22 ; in order to facilitate an operator to rotate the rotatable component  22  of the switch valve  15 , at least one bottom surface of the rotatable component  22  is provided with a handle  23 ; the rotatable component  22  is provided with a first hole  24  and a second hole  25  passing therethrough. A straight line extending direction of the first hole  24  and a straight line extending direction of the second hole  25  are neither parallel to nor intersected with each other. For example, the extending direction of the first hole  24  and the extending direction of the second hole  25  are perpendicular to each other; when the rotatable component  22  rotates to a certain angle, the first hole  24  is communicated with the first oil inlet pipe  18  and the second oil inlet pipe  19  while the second hole  25  is not communicated with either of the first oil outlet pipe  20  and the second oil outlet pipe  21  so that the first oil outlet pipe  20  and the second oil outlet pipe  21  are not communicated with each other. Then, the hydraulic oil from the oil cylinder  10  can pass through the second oil inlet pipe  19 , the first hole  24  and the first oil inlet pipe  18  sequentially and enter into the oil storage tank  13 ; when the rotatable component  22  rotates to another angle, the second hole  25  is communicated with the first oil outlet pipe  20  and the second oil outlet pipe  21  while the first hole  24  is not communicated with either of the first oil inlet pipe  18  and the second oil inlet pipe  19  so that the first oil inlet pipe  18  and the second oil inlet pipe  19  are not communicated with each other. Then, the hydraulic oil from the oil storage tank  13  can pass through the first oil outlet pipe  20 , the second hole  25  and the second oil outlet pipe  21  sequentially and enter into the oil reservoir  11 . In order to protect the rotatable component  22 , the switch valve  15  can also include a protective body  26 . The rotatable component  22  can be encapsulated in the protective body  26 . The protective body  26  can either be of a solid or hollow structure. 
         [0028]    The elastic component  17  in the above embodiment can be, for example, a spring, of which one end is connected to the back part of the oil storage tank  13  while the other end is connected to the clapboard  16 ; when the first hole  24  communicates the first oil inlet pipe  18  and the second oil inlet pipe  19 , the first oil outlet pipe  20  is not communicated with the second oil inlet pipe  19 , hydraulic oil enters into the oil storage tank  13  and pushes the clapboard  16 , the clapboard  16  drives the spring connected to the clapboard  16 , and the spring is compressed to generate elastic force, and finally the oil pressure of the hydraulic oil in the oil storage tank  13  is balanced with the elastic force generated from compression of the spring; when the second hole  25  communicates the first oil outlet pipe  20  with the second oil outlet pipe  21 , the first oil outlet pipe  20  and the second oil outlet pipe  21  are not communicated, and the compressed spring in the oil storage tank  13  tends to resile, and thus, the spring pushes the clapboard  16  to push the hydraulic oil in the oil storage tank  13  out. 
         [0029]    Referring to  FIG. 1 , the hydraulic jack in the embodiment of the present disclosure can further include an oil return valve  27  of which one end is connected to the oil outlet  101  of the oil cylinder  10  while the other end thereof is connected to the oil inlet  111  of the oil reservoir  11 . In an ordinary circumstance (for example, in a case where it is not necessary for a front part bracket S of a hydraulic jack to descend speedily), the oil return valve  27  is closed the oil outlet  101  of the oil cylinder  10  is not communicated with the oil inlet  111  of the oil reservoir  11 , and the hydraulic oil in the oil cylinder  10  enters into the oil reservoir via the oil storage tank  13 ; when it is necessary for the top bracket S of the hydraulic jack to descend speedily, the oil return valve  27  is open, the oil outlet  101  of the oil cylinder  10  is communicated with the oil inlet  111  of the oil reservoir, and the hydraulic oil in the oil cylinder  10  may directly enter the oil reservoir  11  via the oil return valve, so that the hydraulic oil in the oil cylinder  10  is released speedily, and a rapid drop-off of the top bracket of the hydraulic jack is realized. Based on what is needed for application, the descending manner of the hydraulic jack can be selected flexibly by using a component for releasing hydraulic oil in the oil cylinder  10 . 
         [0030]    In the above description on the implementation modes, the features, structures, materials and characteristics can be combined in an appropriate way in any one or more embodiments or examples. 
         [0031]    Although the embodiment of the disclosure has been described above in great detail with general descriptions and specific embodiments, on the basis of the embodiment of the disclosure, various changes and improvements may be made, which is apparent to those skilled in the art. Therefore, all such changes and improvements without departing from the spirit of the disclosure are within the scope of the claims of the disclosure. 
         [0032]    The present application claims priority of Chinese Patent Application No. 201510595694.2 filed on Sep. 17, 2015, the disclosure of which is incorporated herein by reference in its entirety as part of the present application.