Hydraulic roof lifting jack

Abstract

The invention relates to the hydraulic roof lifting jack (100) delivering oil present in an oil reservoir (40) to a cylinder (20) via an operating lever (10), a valve body (50) and a pump (60), and a fluid pumping line (70), comprising a non-return valve (80) positioned after said pump (60), moving a lifting piston (30) having a piston body (31) and a piston rod (32) positioned in said cylinder internal volume (21), and allowing said lifting piston (30) to return by means of a valve (100) and a return line (90) when desired. The invention particularly relates to at least one sealing element (33) positioned on said piston body, in contact with said cylinder and dividing said cylinder volume into a first volume (oil-filled volume) (211) and a second volume (oil-free empty volume) (212); at least one air vent configuration (200) on the said valve body (50) which optionally switches the air outlet opening (203) of the air outlet line (201) from said first volume (211) to the part between said first volume (211) and said check valve (80) positioned after said pump (60) into an open and closed state for air vent in a pressurized state of the oil through said fluid pumping line (70).

Description

[0001] DESCRIPTION

[0002] HYDRAULIC ROOF LIFTING JACK

[0003] TECHNICAL FIELD

[0004] The invention relates to hydraulic jacks for lifting the roof of trailers over short distances.

[0005] The invention particularly relates to the sealing element positioned on the body of the lifting piston lifting the roof and the separation of the cylinder bearing the lifting piston into two separate volumes as oil and oil-free, and the air generated in the system is transported out of the system by means of the air vent structure obtained on the valve body.

[0006] PRIOR ART

[0007] Hydraulic jacks are used for lifting the roof of trailers over a short distance and are used to increase the internal volume of the trailer during loading and unloading processes to ensure efficiency. These systems usually raise the height of the trailer temporarily, and for some country gauge limits permanently, for more convenient placement or removal of particularly bulky loads.

[0008] These jacks make it possible to raise the trailer roof, to make loading equipment such as forklifts work more easily and to load bulky loads without damage. It is used to increase the internal height in order to fit high volume loads into the trailer. Short distance roof lifting saves time, speeds up loading and unloading operations and enables flexible working.

[0009] In some countries, highergauges are permitted, allowing a higher volume of cargo to be loaded onto the vehicle for logistics operations at the borders of these countries.

[0010] The main mechanism of the jack is a hydraulic system that harnesses the power of fluid pressure. Hydraulic oil is pressurized into a cylinder by a pump. This pressure of the oil moves the piston inside the cylinder and forces the piston upwards, lifting the roof. When desired, the pressure is reduced and the system is allowed to descend back in a controlled manner.

[0011] Application ES1065585U is available in the known state of the art. The hydraulic jack used to lift the roof has an oil reservoir configured concentrically with the lifting piston. The oil and indirectly the piston are moved by means of a lever controlled manually by the user. Another application in the known state of the art is application DE202017001822U1. Here, too, there is a manually operated pump. As the pump pumps the oil, the oil fills the oil reservoir configured concentrically with the lifting piston and moves the lifting piston.

[0012] Another application in the known state of the art is application DE102014114098A1. Here, the lifting piston and the oil reservoir are not concentric, but parallel and side by side. It is a solution that eliminates the problem of needing a long lifting height (cylinder length + piston length).

[0013] In all the above-mentioned applications, the oil first fills the cylinder volume used as the oil reservoir and then activates the lifting piston. This is because the oil fills the internal volume of the cylinder before the gap between the cylinder and the piston. Without this filling process, the lifting piston will not move forward to lift the roof. This increases the response time of the lifting piston. In other words, the manually operated pump is moved many times to fill the volume of the cylinder with oil. After the cylinder volume is filled with the structure, the lifting piston is activated and the cylinder is brought to the desired height by moving along its length.

[0014] Systems that fully fill with oil inside the cylinder and then move the lifting piston and systems that move the lifting piston without the need to fully fill with oil inside the cylinder will be able to move the lifting piston the same distance with less oil in the entire system.

[0015] When the hydraulic jack is moved for production, assembly, repair, etc., or its position is changed and it is moved in successive positions parallel or perpendicular to the ground plane, some of the air may mix with the oil. Air mixed into the oil can move to the internal volume of the cylinder where the oil is located. This air mixing phenomenon is an undesirable situation. This is because during the passage of air from the tank to the internal volume of the cylinder, volume changes will occur in the cylinder volume due to the oil + air mixture due to the pressure existing in the system. This causes vibration and turbulence within the cylinder volume. These vibrations and turbulences cause that the system not to work, and the lifting piston does not move forward after the oil is pumped by hand, even though it should move forward with the same response.

[0016] In the known state of the art, utility model application TR2021 011616 U refers to a roof lifting hydraulic jack with an anti-vibration device. Here, the lifting piston is positioned in such a way that it can move in such a way as to lift the roof by means of the pressure coming from the oil sent through a hydraulic valve body into the internal volume of said cylinder from a tank positioned parallel to the cylinder. Here, the lifting piston is moved by means of an actuating lever that pumps oil into the internal volume of the cylinder to move the lifting piston. There is a float floating in the oil inside the tank to prevent vibration. The area with the larger crosssection of the float measures between 50% and 99% of the internal cross-section of the tank. The area of the lower cross-section of the buoy is smaller than the area of at least one crosssection of the buoy parallel to this lower cross-section. All of these sections have an orientation perpendicular to the axial axis of the tank. Here, the piston in the cylinder is positioned in such a way that it can move outward with the pressure from the oil sent from a tank to the cylinder in question through a valve body.

[0017] In all of the applications TR2021 011616 U, DE102014114098A1, DE202017001822U1, ES1065585U, the air vent outlet required for the exhaust of the air entering into the system where only oil is required to be present is located close to the top of the cylinder near the top of the oil reservoir when the cylinder bearing the lifting piston is positioned on the vehicle.

[0018] The location of the air vent outlet near the top of the cylinder or oil reservoir poses two problems. The first is to reach the air vent outlet. The other is the oil dripping onto the vehicle floor and side tarpaulin during air evacuation. The escaping oil splashes onto the side tarpaulin, contaminating it and contaminating the products being transported during the opening and closing of the side tarpaulin. In addition, since the air vent duct is located at a high level, it requires the use of a riser such as a stool, ladder, etc. to reach this duct. Finding this elevation, ascending it, and descending to the ground after the air and oil have dripped onto the floor causes undesirable occupational safety and user health hazards.

[0019] PURPOSE OF INVENTION

[0020] By eliminating the above-mentioned negativities, pollution and occupational accidents are prevented by using less oil, and ensuring that the air mixed into the system over time is more accessible, without reaching high.

[0021] In its most general form, a sealing element is used to achieve these purposes, which is located on the piston body, in contact with the cylinder and divides the cylinder volume into a first volume (oil-filled volume) and a second volume (empty volume not filled with oil). This prevents the oil from moving the lifting piston after filling the internal volume of the cylinder. This also allowed the lifting piston to react more quickly and instantaneously. In addition, the amount of oil to be used in the system is reduced as the entire cylinder volume is not filled with oil unnecessarily.

[0022] On the valve body, an air outlet line is taken from the part between the said first volume and the check valve positioned after the pump. An air outlet opening is obtained at the end of this line. By controlling whether the air outlet opening is open or closed, the air is discharged to the external environment within the system. When the oil is pressurized through the fluid pumping line, air is discharged to the external environment by means of an air vent configuration that can be optionally switched on and off for air vent. In this way, the air outlet opening is obtained and controlled on the valve body, which is in a position where the person can easily reach, preventing contamination of the side tarpaulins and the need to reach high.

[0023] The system is prevented from being damaged due to high pressure and kept in continuous operation by a safety valve that discharges the high pressure that will occur if the oil is continued to be pumped through the operating lever despite the roof reaching the maximum level.

[0024] The oil is cleaned with a filter that cleans the oil pumped into the system before it enters the system and the system is provided to operate for a longer period of time.

[0025] BRIEF DESCRIPTION OF FIGURES

[0026] Figure 1. is a two-dimensional drawing showing the main elements of the hydraulic roof lifting jack.

[0027] Figure 2. is a two-dimensional hydraulic diagram showing the state of the system before the roof is removed.

[0028] Figure 3. is a two-dimensional hydraulic diagram showing the state of the system at the moment the roof is lifted.

[0029] Figure 4. is a two-dimensional hydraulic diagram showing the condition of the air vent configuration and the air vent valve at the moment when the roof lifting system will perform the air vent. REFERENCE NUMBERS

[0030] 100. Hydraulic roof lifting jack

[0031] 10. Operating lever

[0032] 20. Cylinder

[0033] 21. Cylinder internal volume

[0034] 211. First volume (Oil filled volume)

[0035] 212. Second volume (oil-free empty volume)

[0036] 22. Cylinder top point

[0037] 30. Lifting piston

[0038] 31. Piston body

[0039] 32. Piston rod

[0040] 33. Sealing element

[0041] 40. Oil reservoir

[0042] 50. Valve body

[0043] 60. Pump

[0044] 70. Fluid pumping line

[0045] 80. Check valve

[0046] 90. Return line

[0047] 100. Valve

[0048] 110. Safety valve

[0049] 120. Filter

[0050] 200. Air vent configuration

[0051] 201. Air outlet line

[0052] 202. Air vent valve

[0053] 203. Air outlet opening The invention will be better understood when explained with reference to the figures and reference numbers given above.

[0054] DETAILED DESCRIPTION OF INVENTION

[0055] Figure 1 is a two-dimensional drawing showing the main elements of the hydraulic roof lifting jack (100). The hydraulic roof lifting jack (100) consists of a cylinder (20) in which the lifting piston (30) moves and an oil reservoir (40) parallel to this cylinder. The cylinder (20) and the oil reservoir (40) are connected by means of a valve body (50).

[0056] Figure 2 is a two-dimensional hydraulic diagram showing the state of the system before the roof was removed. Said lifting piston (30) comprises a piston body (31) in the cross-section of the cylinder internal volume (21) and a piston rod (32) connected to this body (31). There is a sealing element (33) on the piston body (31). This prevents the oil from moving the piston body (31) after it has filled the entire the cylinder internal volume (21). The piston body (31) divides the cylinder internal volume (21) into two separate volumes. The first volume (211) of these is filled with oil and oil cannot pass to the second volume (212) due to the presence of the sealing element (33). This volume (212) is permanently empty. The second volume (212) remains empty, preventing the passage of air into the second volume (212). The oil in the system is continuously contained in the oil reservoir (40), the first volume (211) and other elements between these two elements. Therefore, in the event of air mixing into the system, the air-oil mixture remains in the first volume (211) under the oil reservoir (40) and the piston body (31).

[0057] When the operating lever (10) is moved, the pump (60) is taken from the oil reservoir (40) and starts to fill the first volume part (211) of the cylinder internal volume (21). Since the oil is prevented from moving the lifting piston (30) after first completely filling the cylinder volume (21), the lifting piston (30) will also move upwards with each movement of the operating lever (10). This depends on how much you want to lift the roof. The oil transfer to the pumping line (70) is carried out to the first volume (211) of the cylinder by means of the operating lever (10) and the pump (60) in the amount desired to lift the roof. This situation is illustrated in Figure 3. If the oil is continued to be pumped by means of the operating lever (10) despite the roof reaching the maximum level, the high pressure will be returned to the oil reservoir (40) by means of a safety valve (110). In addition, the oil pumped into the system is ensured to pass through a filter (120) before entering the system, thus enabling making the system work with a cleaner oil.

[0058] Figure 3 is a two-dimensional hydraulic schematic showing the state of the system when the roof is lifted. There is a non-return check valve (80) on the pumping line (70) which prevents the return of the fluid allowing one-way movement. At this time, the pumping line (70) cannot move forward due to the check valve (80) on it. An air vent configuration (200) is again obtained on the line between the cylinder (20) and the check valve on the pumping line (70). The air vent configuration (200) is configured on the valve body. An oil outlet (201) is taken from the oil pump line (70) between the cylinder (20) and the check valve (80). This line is directed to a manually controlled air vent valve (202).

[0059] The air vent valve (202) is normally closed. Even if the oil is pressurized when the valve (202) is closed, no oil or air is discharged to the atmosphere through the oil outlet line (201). In the case where pressurized oil is present in the pumping line (70) when the lifting piston (30) is upwards the air vent valve (202) will be trapped in a pressurized state between the check valve (80) and valve (100) when the valve (100) is closed.

[0060] When the system is in this position and the air and oil mixture is allowed to leave the system through the air outlet line (201), the air inside the system will quickly leave the system. A manually operated air vent valve (202) is provided to remove the air entering the system from the system. When the normally closed position that does not allow air outlet is turned to the position that allows air outlet, the air will leave the system by being directed to the air outlet opening (203) due to the pressure in the system. This is illustrated in Figure 4. After the air leaves the system, the air outlet line (201) is closed again.

[0061] When the air outlet line (201) is closed, the fluid is directed onto the oil return line (90). A valve (100) is provided on the return line (90). When the valve (100) is opened, the fluid cannot move forward due to the check valve (80) on the pumping line (70). Changes direction to the return line (90). Depending on the amount of opening of the valve (100), the fluid will fill the oil reservoir (40) with high or low flow rate. The system will return to the initial position in figure 2.

Claims

CLAIMS1. A hydraulic roof lifting jack (100) delivering oil present in an oil reservoir (40) to a cylinder (20) via an operating lever (10), a valve body (50) and a pump (60), and a fluid pumping line (70), comprising a non-return valve (80) positioned after said pump (60), moving a lifting piston (30) having a piston body (31) and a piston rod (32) positioned in said cylinder internal volume (21), and allowing said lifting piston (30) to return by means of a valve (100) and a return line (90) when desired, characterized in that it somprises the following;• at least one sealing element (33) positioned on said piston body, in contact with said cylinder and dividing said cylinder volume into a first volume (oil-filled volume) (211) and a second volume (oil-free empty volume) (212);• at least one air vent configuration (200) on the said valve body (50) which optionally switches the air outlet opening (203) of the air outlet line (201) from said first volume (211) to the part between said first volume (211) and said check valve (80) positioned after said pump (60) into an open and closed state for air vent in a pressurized state of the oil through said fluid pumping line (70).

2. A hydraulic roof lifting jack (100) according to claim 1, characterized in that it is characterized with a safety valve (110) which relieves said oil reservoir (40) of the high pressure which would be generated if the oil were continued to be pumped by means of the operating lever (10) despite the roof reaching to the maximum level.

3. A hydraulic roof lifting jack (100) according to claim 1, characterized in that feature; it is characterized with air vent configuration (200) having a manually controlled air vent valve (202).

4. A hydraulic roof lifting jack (100) according to claim 1, characterized in that it comprises a filter (120) which cleans the oil pumped before it enters into the system.

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