The principle of operation is simple - when the gate goes down, the spring twists and accumulates energy, while preventing the gate from falling. At the moment of upward movement, the spring gives off energy and helps to lift the canvas with less effort.
The shaft with torsion bars is installed horizontally, above the sectional door opening, or in the depths of the room, in case of low mounting.
General form
Sectional doors are one of the types of industrial doors that are often installed in Russia and Europe.
Design
The basis of the design of sectional doors is a lifting mechanism, consisting of a tension spring and drives that balance the door in any position by balancing the leaves. This allows you to open them manually, with the least effort.
The spring system itself consists of 2 torsion springs made of spring steel, working "in torsion".
At the time of operation, the diameter of the coils becomes smaller, and the length of the body increases as the spring winds up.
Torsion springs can be left-handed or right-handed, and must be designed so that an applied force will wind the spring (rather than spin it). They work best when they are supported by a hub, shaft, or tube inserted through the body spools.
Torsion (French "torsion" - twisting) is a spring, in the form of an elastic cylinder, accumulating and transmitting mechanical energy to the mechanism holding it.
Manufacturing process of torsion springs
Typical sizes (available).
| Torsion spring sizes |
| 9x113x1600 |
| 6x80x820 |
| 9x113x4000 |
| 8x111x4000 |
| 8x120x1060 |
| 10x65x930 |
| 6x62x1000 |
| 8x11x1100 |
| 6x75x700 |
| 6x62x1100 |
Principle of operation
The principle of operation is simple - when the gate goes down, the spring twists and accumulates energy, while preventing the gate from falling. At the moment of upward movement, the spring gives off energy and helps to lift the canvas with less effort.
The shaft with torsion bars is installed horizontally, above the sectional door opening, or in the depths of the room, in case of low mounting.
Spring types.
There are singles and pairs:
- If the springs are single, then each works separately. If even one breaks, the entire sash is blocked.
- If the design is paired (double), "one inside the other", then they work together, "helping" each other.
If one breaks, the gate continues to work.
In a double torsion spring:
- consider each half of the spring separately, and then calculate the total torque as the sum of the torques of the two halves
- the two sets of turns are connected by a central "tongue" and can operate either in parallel or independently.
Advantages of pair systems:
- compact arrangement does not require additional space on the shaft;
- power characteristics are improved;
- service life is extended.
Disadvantages of paired systems:
- difficult to measure their size. Before getting to it, you need to unwind the external spring and dismantle the mechanism holding it;
- the difficulty of determining the breakdown of the internal spring. This can only be understood with a sudden decrease in their "lifting" force.
Reasons for popularity
- They create the right balance between the weight of the canvas and the necessary effort to lift them.
- Are issued from the domestic and import bar having the certificate of conformity.
- They are used in the manufacture of sashes (the size from the top of the opening to the ceiling is from 250 to 400 mm, with the width and height of the opening - up to 5000 mm).
- Available with powder coating, galvanized or painted.
What should be taken into account when ordering?
When replacing, consider 2 points:
- Work load. Installing a "cheaper" model will lead to rapid wear and tear of the entire mechanism.
- Conformity. If you change one of the paired springs, order it from the same manufacturer, or change both at once.
How to measure dimensions?
Use a caliper and tape measure to measure the following dimensions:
- length height).
- outside diameter
- The diameter of the wire
Additionally, in the application, indicate the direction of winding: right or left.
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