Since ancient times, people have faced the problems of lifting a large load to a height, for this usually many people were involved, and bulky structures were erected that did not always have super strength, and therefore often broke, provoking human casualties. The way out appeared with the invention of such a machine as a hydraulic jack, which is widely used today. Such an installation, unlike winches, has greater reliability and is able to lift large loads at a lower cost.
Purpose of the hydraulic jack
Today, it is impossible to imagine carrying out repair work on a car, whether it is a suspension repair or a wheel change, without the use of jacks - special mechanisms that are designed to lift a heavy load and fix it at the required height. The most effective are hydraulic jacks, where the working force is created using hydraulic oil and a piston.
The first mechanical jacks appeared in antiquity. And the idea of \u200b\u200bcreating a hydraulic jack circuit specifically for a car arose unintentionally. Repairman Peter Lunaty spied on this idea in a barbershop, surprised at how easy it is for a haircut master to fix a hydraulic chair at a certain height. In 1925, a complex platform lift was made with a hydraulic rack for a car.
Hydraulic jacks are distinguished by their carrying capacity, which ranges from one to several hundred tons, which allows them to be used in the repair of trucks and other heavy equipment.
Machine bodies or flooring, foundation slabs and columns are used as loads. Depending on the purpose of application, such equipment has various dimensions and designs.
The hydraulic jack is used to move, lift and fix loads. The device is used in the field of general plumbing and tire fitting, and is also indispensable when preparing the car for a long trip to create balancing: the wheel is removed with a jack and balanced on special equipment.
Modern hydraulic jacks are widely used not only in service stations and car services. They are successfully used in oil refineries, power plants and other industrial complexes. The highest level of performance and ease of operation allowed this technology to be introduced into the domestic environment, which is why many owners have a hydraulic jack in the garage.
This equipment is capable of operating in horizontal and vertical planes, therefore it is widely used at the construction and assembly site and for tensioning reinforcing structures made of prestressed reinforced concrete.
Hydraulic jack design
The main load-bearing elements of a hydraulic jack are the body, the working fluid, usually oil, and the retractable piston. The hydraulic jack has an elongated or short body, which is made of hardened steel. The housing performs the following functions: it acts as a guide cylinder for the piston and is a reservoir for working oil.
A screw with a lifting heel is screwed into the plunger, turning the screw out, so if necessary, it turns out to increase the maximum lifting height. The jack of this type is equipped with a hydraulic pump with a manual, foot or air drive. The hydraulic jack device is provided with safety valves and other devices to create a long trouble-free operation.
The lifting mechanism and the retractable hydraulic cylinder, which is lifted up by a special platform, are located in the openings of the body. The descent occurs by turning the T-handle. The equipment has polyamide wheels that provide the jack with maneuverability. The body of the elongated dash is used mainly for working with buses and heavy vehicles.
The principle of operation of the hydraulic jack
Any hydraulic jack works according to the principles of communicating vessels using a liquid. Before work, it is necessary to place the jack on a flat hard surface under the car and press the lever with the valve closed until the car rises to the required height. The descent of the car is carried out by means of a smooth opening of the valve of the device counterclockwise.
The working hydraulic oil is pumped by a drive pump using a lever. Liquid enters the cylinder through the valve and squeezes it out. The reverse flow of fluid will be prevented by valves - discharge and suction. To lower the jack back down, it is necessary to open the valve on the pump, then oil will flow from the cylinder back to the pump.
The presence of a thread on the body of the jack, which is protected by a dirt-proof casing, a thread on the rod and threaded holes in the base guarantees unlimited possibilities for using and operating hydraulic jacks for crimping, clamping and bending. The high-strength support, which is made of hardened steel and mounted on the rod, is able to protect the hydraulic jack from damage. The corrugated surface of the support prevents the goods from sliding. The force of hydraulic jacks is regulated by a built-in pressure gauge.
Advantages and disadvantages of hydraulic jacks
Hydraulic jacks are one of the most unpretentious for all their power. An important feature of hydraulics is an incompressible working material. Hence - the smoothness of lowering and lifting, fixing the load at the desired height and braking accuracy. Hydraulic jacks demonstrate a high level of efficiency - up to 80% and a significant load capacity - up to 200 tons with little effort due to the large gear ratio between the cross-sectional surfaces of the pump plunger and the cylinder.
But with hydraulic jacks, the initial lifting height is much higher than with mechanical models. Another difficulty is the inability to accurately control the height of the lowering. To maintain the jack in working order, it is necessary to constantly monitor the oil level, control the tightness of valves and seals. Such jacks can only be transported and stored in an upright position, otherwise the liquid may leak out of the tank.
The disadvantages of hydraulic jacks follow from the advantages. They are relatively slow - one pump cycle corresponds to a not too high lift height. The disadvantages include a large mass and size, the high price of a hydraulic jack, as well as a small stroke for single-plunger models. In addition, these tools often have more serious breakdowns and malfunctions than mechanical devices.
Classification of hydraulic jacks
There are several types of hydraulic jacks.
Bottle hydraulic jacks
The design of the bottle (vertical) hydraulic jack is the simplest. The scope of use of such jacks is quite wide due to the large range of lifted weight - from 2 to 100 tons. "Bottles" are used in trucks. In addition to the main advantages of a hydraulic jack, vertical models have several more - this is versatility of use, compactness and a large support area.
Bottle jacks are available in single and double stems. The hydraulic single-rod apparatus is distinguished by its simple design and ease of operation, which expands its areas of use and allows you to perform work of any complexity: installation and dismantling in mechanical engineering, construction, car repair, railway car wheels, use as a power unit of a press, pipe bender, pipe cutter and similar tools .
The telescopic two-rod jack has a similar design with a bottle machine, the principle of operation of a hydraulic bottle-type jack is based on the use of several working rods. The piston is at the base of the telescopic jack. It can be applied in horizontal and vertical position. It is compact and fits most cars. Lifting occurs with the help of a lifting lever actuated by a hydraulic cylinder.
Rolling jacks
The rolling jack works on the same principle as the bottle jack, but with the difference that the axis of the working cylinder is not located in the vertical axis, in addition, the piston is not directly aligned with the pickup and the lifting lever is actuated. This device is called rolling because it is a trolley on wheels that can roll on a flat surface. When lifting the pickup and the lever, the jack “rolls up” or shifts under the load.
Such a jack is driven by the same swing of the lever as the bottle models, it is lowered in the same way - by turning the valve screw. If it is necessary to lower the load down, it is necessary to put the tubular handle on the valve screw, after which the partition will enter the groove of this screw. By rotating the handle around its axis, the user rotates the screw, respectively, relieving pressure in the working cylinder and lowering the load to the required height.
Most often, a rolling jack can be found at a tire shop, because it is ideal for lifting one side of the car, it is quite fast in operation and installation. The disadvantages of such a design follow from the name - a rolling jack needs a flat hard surface, concrete or asphalt, to work. In addition, the significant size and weight make it difficult to transport the unit in a car.
Rolling jacks are classified according to their purpose, as in the photo of hydraulic jacks:
- For personal use by a motorist, with a carrying capacity of up to 3 tons;
- For car services and tire shops, with a load capacity of up to 4 tons and with the presence of pre-lift pedals for instantly reaching the required pickup height;
- For maintenance of heavy machines and special vehicles (forklifts), with a carrying capacity of up to 20 tons and with the presence of preliminary lifting pedals and a sliding traverse, which is designed to lift one side of the machine.
Transmission rolling jacks are equipped with a special swivel frame. Here, the smoothness and precision of the hydraulic jacks are manifested in all their glory. The gearbox of a car that is mounted or dismantled can be accurately fixed in a horizontal or vertical plane in the desired position.
Hydraulic hybrids
Two-level jacks are needed mainly in car services where they work with different cars. The features of this device include two lifting platforms. The drawing of a two-level hydraulic jack as a whole is a hybrid of a rolling and bottle jack. To be more precise, a two-level jack is used at a height of 65 - 375 millimeters from the ground as a rolling jack and at a height of 375 - 687 millimeters as a telescopic one. When working with a lifting mechanism, use a hand lever and a foot pedal.
The pneumatic hydraulic jack combines hydraulics and pneumatics. It can be manufactured in a rolling solution, has a load capacity in the range of 2 - 80 tons. The initial pickup height is low. It is used exclusively as equipment for car service.
towing jacks
Low-lift towing jacks are widely used wherever a low lifting height is needed: for the installation and dismantling of various equipment, for lifting railroad tracks, as well as in car workshops. It is precisely such a low pickup height, which is from 15 millimeters, with the possibility of its step-by-step adjustment, that is very convenient when assembling mechanisms and is the hallmark of a towing jack. But at the heart of this jack is a simple bottle-type device.
Diamond jacks
The hydraulic diamond jack is mainly required for lifting machines during repairs. It is characterized by high reliability, if we compare it with a screw relative, and is practically not inferior to it in ease of use.
In a diamond jack, four levers act as load-bearing elements, which are connected by hinges. The scheme of operation of a hydraulic jack and lifting loads is based on changing the angles between the levers. The advantages of diamond jacks include small dimensions, which provides convenient storage, transportation and, at the same time, a significant supporting surface and structural rigidity. Relatively low lift height.
Hydraulic press manufacturing
When a car enthusiast maintains his entire fleet on his own, one of the most necessary tools is a press. We suggest you make a press from a hydraulic jack with your own hands, which will become a reliable companion when performing a whole list of works. With its help, you can punch holes in different materials, press in inserts and bushings, and press metalworking waste.
Assembling a hydraulic press is not that difficult. You will need for this a welding machine with the required number of welding electrodes, a hacksaw, an angle grinder with a metal disc, a thick-walled steel profile to complete the press design. The functions of the power unit, which provides the necessary working pressure, are performed by a hydraulic jack.
The first node of the hydraulic press is the support platform for the jack. Since the resulting pressure will be proportionally applied to the base and upper working units, the strength of the base should be maximum. This can be achieved by making several stiffeners on the basis. To make the base, take a steel square or rectangular profile that has a size of 40 by 50 or 50 by 50 millimeters and cut 4 parts about 250-300 millimeters long using the above tools.
After that, it is necessary to lay these parts side by side to each other and weld the connecting seams from above and below to increase the rigidity of the press base. To ensure greater stability of the hydraulic jack, weld a steel plate to the resulting structure, the sheet of which has a thickness of 8-12 millimeters and a size of 250 by 200 millimeters.
The next step in the manufacture of a homemade press from a jack is the production of an emphasis and racks. To do this, it is necessary to saw off 2 parts from a profiled thick-walled pipe of a rectangular or square shape of the required length. In order to calculate it, it is required to clarify the value of the maximum stroke of the rod according to the attached instructions for the jack and add the height of the hydraulic jack itself and the support platform to the resulting size.
Make the emphasis from the material that the racks are made of. The length of this part must be equal to the width of the support platform in order to maintain the overall geometry of the structure. Connect the stop and the obtained racks with each other with a welded seam and weld the U-shaped structure to the base.
When performing such assembly operations, it is recommended to use a simple fixture that ensures the perpendicularity of the parts to be joined. On a steel sheet that has a thickness of at least 10 millimeters, two trimmings of a steel corner 40 by 40 millimeters should be welded at an angle of 90 degrees. Lay the parts to be joined in the future in this fixture and weld.
This way you can achieve the desired connection angle. For additional convenience, this impromptu square is additionally equipped with clamping devices that fix the parts to be joined and prevent the joint angle from breaking due to thermal changes during welding in the metal.
The next mandatory element of our press is a removable stop, which is able to move along the guides and transfer pressure from the central working rod of the hydraulic jack to the workpiece. Prepare for its manufacture several pieces of steel strip, which has a thickness of about 1 centimeter. Make the length of the parts less than the resulting distance between the racks. Connect the resulting parts in several places by welding on both sides.
To ensure a quick replacement of this part when performing any hydraulic work and to fix the element when moving on vertical racks, it is necessary to drill two through holes in the resulting block of steel strips and saw off two plates, their length should be 100 millimeters longer than the length of the block. Also drill two holes in the plates, which are bearable with the holes in the block.
When mounting the block on the frame of the press from a hydraulic jack with your own hands, select two bolts of the required length with nuts and washers and connect the resulting plates to the block so that they are located on both sides of the racks. If there is a need to achieve a smaller free play of the hydraulic jack piston, it is possible to reduce the space between the moving stop and the upper beam of the structure with the additional installation of an intermediate square profile.
To do this, saw off a piece of a square profile, which has a length that is equal to the distance between the uprights, and attach it at an equal distance of welds. This will significantly reduce the working distance of the hydraulic press and reduce the time spent on certain types of work.
To further reduce the stroke of the working rod of the hydraulic jack, you can use additional replaceable inserts, which are made of a solid or hollow steel profile or replaceable anvils. To create them, you should saw off several parts of different thicknesses and additionally mark them for a quick and careful selection of the desired element.
Hydraulic jack repair
Hydraulic jacks periodically need maintenance, therefore, it is necessary to add liquid to the working cylinder, which flows out during operation through oil seals and various seals. In addition to oil leakage, jack malfunctions consist in jamming when lifting a load to a certain height, the inability to lower the jack after lifting, or the inability to lift even a light load.
Oil leak
To repair and test a hydraulic jack at home, you should buy the right equipment repair kit. Before repair, the machine must first be disassembled. An extension to the keys may be required to have significant force and more leverage. Be sure to prepare a container to drain the old oil and prepare a new working fluid.
After that, the pistons should be removed and checked for corrosion. It is customary to remove all dirt and corrosion. Check if the stem is bent. If deformation occurs, then it is unlikely that it will be possible to make it even again and you can no longer repair anything.
Check the oil bypass valve. To do this, the valve is unscrewed and checked for deformation or dirt ingress into the valve. If the valve is defective due to mechanical deformation, then it should simply be replaced. In addition, it can simply become dirty, and the ball will sit loosely in its saddle. This is the reason for the transmission of the working fluid.
Drain the old oil completely. This procedure is quite simple, although it takes a long time until the oil flows from one cylinder to another. The liquid is drained by pumping the system, moving the lever up and down. Rinse all parts thoroughly to remove dirt and oil residues. Completely change all cuffs and sealing gaskets.
Another cause of failure of the hydraulic jack can be considered dirt that has entered the working cavity. To remove it from there, it is necessary to unscrew the head of the housing, pour kerosene into its base and pump the jack with the locking needle unscrewed. At the end of the operation, kerosene should be removed and clean oil should be poured into the working cavity.
Air entry
In the working cavity of the jack during long-term operation, air bubbles accumulate, significantly reducing its effectiveness. The reason for this, as a rule, is air that has entered the hydraulic system due to a lack of working oil. You can fix this problem as follows.
First, open the oil reservoir cap and bypass valve, and then quickly pump the hydraulic press pump several times. In this way, air will be forced out of the working cavity into the oil container. You can then close the bypass valve and the hole leading to the oil tank. If you did everything right, then the air will be removed, and the jack will again work in normal mode.
If your attempt was unsuccessful, repeat all of the above steps. However, this method is not the only way to remove air from the working cavity. It is not difficult to determine the presence of air in the working cavity: the jack does not work at all, or the load is lifted slowly.
First of all, unscrew the locking needle one and a half to two turns, then lift the plunger with your hand by the screw to the extreme upper point and release it so that it is again in the lower position. Repeat these steps twice or thrice. To prevent such a problem from occurring in the future, it is worth periodically checking the oil level in the hydraulic jack and, if it is lacking, add working fluid.
Thus, you got acquainted with the design of the hydraulic jack, studied its advantages and disadvantages, understood the classification of such equipment and understood how the hydraulic jack works. Now you can start assembling the device with your own hands. And do not forget about periodic maintenance and adding working oil.
The problem of lifting loads of large masses in front of mankind has been standing for a long time. In recent years, jacks have been increasingly used to solve it. The hydraulic jack stands apart in this row. He is able to lift really heavy loads with a minimum of effort. Hydraulics, since the advent of science, has come to the aid of man. There are situations when a lift of this kind is simply necessary, but there is no way to purchase it. How to make a homemade jack?
Design and features
Of course, before starting work directly, it is imperative to learn more about the design of the hydraulic jack. In fact, it is not so complicated as it might seem at first glance. The main elements are the body, pump, plunger, screw with lifting heel. The hydraulic jack is most often made of hardened steel. In this case, a special oil with high viscosity indicators acts as a working fluid. Conventional motor oil will not work in this situation.
It is worth considering this when developing a device. Usually it is the body that is the main part of the hydraulic jack. It serves not only as a reservoir for the working fluid, but also as a real cylinder for the piston. The device of this design implies the presence of protective valves that ensure uninterrupted operation. It is equipped with a hand or foot pump.
The oil is drained using a special handle, which is part of the mechanism. At the same time, the lifting mechanism and a special retractable hydraulic cylinder are able to raise the working platform. A sufficiently high pressure is created, which allows you to lift loads of various masses. The body of such a device can be both short and elongated. The second option is most often used when carrying out repair work on heavy equipment. For example, it can be a bus or a heavy vehicle.
Having at hand a drawing - a screw jack, we make it with our own hands from steel bent equal-shelf channels GOST8278-83.
In the figure, the types of sizes of the assortment used are highlighted in blue rectangles
The screw jack consists of the following parts:
Base
Lower shoulder
upper shoulder
Emphasis
screw mechanism
BASE
Let's make from a range with a cross-sectional area of \u200b\u200b2.63 (cm²). We drill four through holes with a diameter equal to the diameter of the pin. When drilling, strictly maintain the center distance between them. If necessary, the base can be attached to a wider removable platform.
LOWER SHOULDER
We will produce from a range with a cross-sectional area of \u200b\u200b1.99 (cm²) by analogy with the base.
UPPER SHOULDER
Let's make from a range with a cross-sectional area of \u200b\u200b2.28 (cm²) by analogy with the lower shoulder.
UPOR
Let's make from a range with a cross-sectional area of \u200b\u200b1.99 (cm²) by analogy with the upper shoulder.
From above, we fasten the rubber gasket.
SCREW MECHANISM
1. Shaft - screw. We will make from a metal bar with a diameter of twelve millimeters. On the one hand, there is an M12 thread, on the other, a retainer, which is attached to the shaft with a cotter pin through a through hole on the shaft.
2. Axis - emphasis. Relative to which the rotation of the lower and upper arms occurs.
The axles on both sides are pins with cylindrical flat heads, which are attached to the axle with cotter pins.
A through hole with a diameter of ten millimeters was drilled in one stop, and an M12 internal thread was cut in the other.
3. Retainer. Fixes the shaft from the side of its rotation and provides the possibility of transmitting torque to the shaft.
Performance characteristics of a do-it-yourself screw jack.
Before you get to work and make a pneumatic jack with your own hands, you should know more about such an auxiliary tool.
An inflatable jack is the most elementary option of all analogues. The convenience of such a tool is that it is unpretentious in use, it does not need a flat area. Having such a jack in the trunk and once in a swampy loose area, you can not be afraid to use it. In addition, with the help of it you can not only replace the problematic wheel, but also get out of the mud. Working with it, no special physical effort is required, so it is even used in carrying out rigging work.
Working principle of pneumatic lift
The main working element of this jack is the rubberized pillow. It is made of a special durable material so that the unit can withstand loads in the range of 4-5 tons.
To power such a tool, it is placed under the bottom of the machine and connected to a pump or other air source, such as a compressor or a compressed gas cylinder. There are models that are especially popular, since their work can be carried out, one has only to connect such a jack to the exhaust gases of a car. They do not need any additional equipment. Such structures are called air jacks or pneumocrates.
For such a device, a hose is enough to connect the exhaust pipe and the jack itself, and then turn on the engine. It takes literally 2 minutes for the tool to do its job. In this version of the device, there are no complex mechanisms that carry out work due to pneumatics.
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Technical characteristics of pneumatic jacks
There are three main points on which such a device is evaluated:
- Load capacity. For the tool to be safe to use, this indicator must exceed the mass of the car itself. If the car is a passenger car, then the carrying capacity should be 1.5-2 tons, and if the car is of the Gazelle type - 2.5-3 tons.
- Pickup height. This parameter should be paid special attention if the car has a small ground clearance. You should be interested in this moment in the case of frequent car stuck in the mud. It is best if this characteristic is within 10 cm.
- lift height. For pneumatic models, this figure does not exceed 50 cm. But in fact, this is enough to cope with the replacement of wheels. If you use a jack, which is used for rigging, and it, in turn, is connected to compressors, then this characteristic will be greater - up to 70 cm.
In any case, when choosing a jack, you should be guided by a personal car and the conditions in which it is most often located.
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How to make a jack with your own hands
You will need the following items:
- an old pillow from a truck;
- bolt of the appropriate diameter;
- a ball that can be freely located in the bolt;
- wheel bolt from Zhiguli;
- chamber fitting;
- drill.
From these components, a structure is assembled. A bolt is screwed into the pillow hole, focusing on the existing thread. In advance, a hole should be drilled in it into which the chamber fitting will be inserted.
The role of the valve will be performed by a wheel bolt from the Zhiguli, in which a hole should be made. Now these elements need to be connected. But before doing this, a ball is placed in the existing outlet so that in the process of work it can close the hole, then the air will not come out.
To use such a device, you will need a special pump. The jack is installed under the bottom of the car. In such a device, you will need to use a small wooden block, which will rest against the car. If desired, a cart with wheels can be attached to the bottom, then it will be a rolling jack.
There is one inconvenience of such a homemade device. The pillow from the truck is quite large. Therefore, if the car has a low landing, then it will constantly have to be raised to substitute the jack.
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Lifting Power: Highlights
There are several options for how a jack can raise a car:
- Pneumatics. In this variant, the lifting of the load is carried out using the power of compressed air. Such models work both from equipment and from the exhaust gases of the car themselves. Air enters the chamber, and that, in turn, begins to increase in volume, due to which the transport rises. The convenience of using such models is that no special efforts are made, and with a compressor, the process takes only a few seconds.
- Mechanical. To use this analogue, it is necessary to make twisting movements with the handle or use another similar method. Such jacks are quite affordable, besides they have small dimensions.
- Hydraulic. The principle is similar to the previous option, the only difference is that in this case less effort will be expended. This is due to the fact that the design of the device contains a liquid that ensures the expulsion of the plunger with the load due to the resulting pressure. This option has a long service life.
- Mechanical with electric drive. In this embodiment, all the work for a person is done by electricity. The amenities here are undeniable, but only as long as there is food. As soon as the light is turned off, you will have to work in the same way as ordinary mechanical ones, with the only difference being that more effort will be needed.
Depending on the scope of the jack, the required model is selected.
Despite the fact that the pneumatic jack is the easiest to use, there are some nuances in its use. To avoid the tool flying out from under the machine, it must be properly laid. Therefore, before using a new device, it is better to empty it once, after which it descends and folds properly by itself. In the process of work, it will be useful to cover the surface of the floor and the jack with some kind of rugs. This will protect the instrument from damage.
The materials for the manufacture of the chamber are taken on the basis of PVC, and he, in turn, becomes quite rough as soon as frost appears on the street. It is optimal to use until the thermometer shows -10, then operation becomes difficult.
The convenience of such a jack is that with its help you can raise the car from almost a minimum height. And if there is no desire to spend money, then you can always do it yourself.
A jack is a device that should be located both in the trunk of a car and in the garage of a car enthusiast. At the same time, it is better to choose the second option more massive with universal functionality and a high load capacity. These characteristics are 100% do-it-yourself, which will not be difficult to do.
Characteristics of the pneumatic device
There are three main criteria by which a homemade inflatable jack is evaluated:
- load indicator. To ensure safe operation, this value must exceed the weight of the vehicle. For a passenger car, a characteristic of about two tons will be enough; maintenance of heavier vehicles requires a carrying capacity of at least 2.5 tons.
- Pickup height. This aspect plays an important role if the car has a small ground clearance. The optimal indicator is a value of at least 100 mm.
- Lift level. Homemade pneumatic type jack has a height of not more than 500 mm. This reserve is quite enough for changing wheels and some other work, the rigging unit with connection to the compressor allows you to raise the car up to 70-80 cm.
Definitely, when choosing a jack and its manufacture, first of all, you need to focus on your car, the conditions for its operation and storage.
How to make a jack yourself?
To build a jack with your own hands, you will not need much material and effort. You need to select the following items:
- a used pillow from a truck;
- suitable bolt;
- ball element;
- wheel VAZ lock;
- union;
- drill as the main tool.
The structure is assembled from the presented elements. A bolt is screwed into the hole in the pillow. First you need to make a socket for the fitting from the camera.
A wheel bolt from a VAZ is used as a valve, in which a hole is drilled. At the next stage, the existing elements are connected after a ball is installed in the hole, which will serve as an air intake.
Peculiarities
For the practical implementation of this device, a special pump is required. The inflatable jack is installed under the bottom of the vehicle. For safety, it is advisable to use a wooden stand that will interact directly with the machine.
This mechanism has one significant drawback. Since the cargo cushion has a decent size, a low-slung car will have to be raised beforehand to install the device in question. If you attach a cart with wheels to the bottom of such units, you will get home-made ones for cars.
Comparative characteristics
The pneumatic version lifts the load due to the compression force of the air mass. Such modifications work from connection to additional equipment or from the exhaust of the machine. The air mass enters the chamber. Due to compression and increase in volume, the car rises. The advantage of the models is that you do not need to make special efforts, and in the presence of a compressor unit, the process takes a matter of seconds.
A mechanical jack for a car involves bringing it into operation by rotating or twisting a special handle. Such modifications have a low price and compact size.
The principle of hydraulics is similar to the mechanical version. The difference lies in facilitating the process of pumping out the working part of the jack, due to the presence of liquid in the working system. Such modifications have a long service life.
A mechanical jack with an electric drive is powered by mains power, all the main work of the device is performed by electricity. The advantages of the device are undeniable, but you need to connect it to the outlet.
Security measures
Despite the fact that the inflatable jack is one of the most elementary in terms of operation, its use requires certain precautions.
To prevent the unit from flying out from under the car, it must be installed correctly. Before installing a new pneumatic device, it is advisable to deflate it once without load, after which it descends and fits itself accordingly. To protect the jack from damage, it is better to lay a rug on the floor.
For the manufacture of the working chamber of the device, materials based on PVC are suitable. At sub-zero temperatures, this design hardens and becomes rough. According to experts, the optimum operating temperature is up to -10 degrees.
Hydraulic lifting device
It is quite possible to make a hydraulic jack with your own hands. It is based on a body, the main bearing function is performed by a retractable piston and a working fluid (oil). Variations of the fixture can be made with a shortened or elongated steel frame. The housing is a reservoir for oil and a guide cylinder for the piston.
A special adjusting screw with a lifting heel is screwed into the plunger, if necessary, you can increase the maximum lifting height. Such a device is equipped with a manual, foot or air type drive.
The working mechanism and the retractable cylinder are located in the holes of the frame. The unit is lowered by turning the T-handle. Some devices are equipped with polyamide wheels that provide maneuverability. Operational safety is ensured by safety valves.
Positive and negative sides of the hydraulic device
Before you make a jack with your own hands, you should consider all its pros and cons. The advantages of a hydraulic device include the following indicators:
- the device is unpretentious in maintenance and operation at a fairly high power rate;
- smooth running of the working rod, reliable fixation of the load at the desired height, braking accuracy;
- high efficiency (up to 80%) and load capacity (over 150 tons).
The disadvantages of using the hydraulic model include a high initial lifting height, the problem of the accuracy of lowering position control, a decent price and quite a lot of weight. Store and transport the device only vertically, otherwise the working fluid may leak out.
Conclusion
Making a jack with your own hands will not be a particular problem. Depending on the possibilities, the scope of use and other objective circumstances, you should choose the right model for the type of work. For use on the road, a compact device of a mechanical or hydraulic type is suitable, and in the garage an inexpensive and practical pneumatic device will work perfectly.