This article from our series on Lift tables types and their advantages and disadvantages introduces you to spindle lift tables.
How a spindle lift table works
The basic principle of a spindle lift table can easily be explained by the interaction of a screw and a nut: When the screw rotates, the nut moves along the screw axis.
In a spindle lift table, the load-bearing nut is connected to one of the two scissor arms. The counterpart is located on the other scissor arm. An electric motor rotates the lifting spindle, causing the scissor mechanism to either steepen or flatten depending on the direction of rotation, in order to lift or lower the load.
The design of spindle lift tables became popular in the early 1990s. Initially, self-locking trapezoidal spindles were used to meet safety requirements. However, since the mid-90s, ball screw spindles have increasingly replaced trapezoidal spindles.
Advantages of spindle lift tables
As mentioned earlier, there are two drive concepts for spindle lift tables: the trapezoidal spindle and the ball screw spindle. Both systems offer specific advantages and disadvantages, which will be examined in more detail below.
Trapezoidal vs. ball screw spindle
The major advantage of the trapezoidal spindle lies in its self-locking mechanism, which prevents the platform from lowering unintentionally. However, this very feature also brings disadvantages: In order to move the platform, a relatively high breakaway force must be overcome. This requires a drive motor that provides more power than is technically necessary for normal operation. The oversized motor and the relatively high mechanical friction of the trapezoidal spindle result in corresponding energy consumption for the spindle lift table.
The use of a ball screw spindle, on the other hand, largely eliminates these disadvantages. By sacrificing the high self-locking capability, the required motor power can be nearly halved.
No hydraulic oil
Similar to belt-driven lift tables and lift tables with chain drives, spindle lift tables do not rely on mineral oil for power transmission. This eliminates the risk of leaks, making the lift table ideal for use in sensitive areas, such as the food industry.
High positioning and holding accuracy
Thanks to the mechanical power transmission, the spindle lift table offers high positioning accuracy. Multiple stop positions can be approached with precision. Maintaining a position over a long period is also easily achievable for the spindle lift table.
High construction height
Compared to other drive concepts, the spindle drive has a relatively high construction height, as it cannot be placed outside the lift table. As a result, particularly low construction heights cannot be achieved with a spindle lift table.
Higher wear and tear
Compared to hydraulic lift tables, spindle lift tables are subject to higher wear and tear. This is especially true when using a trapezoidal spindle, where the lifespan can be significantly shorter than that of a hydraulic scissor lift table. To ensure a long service life despite this, the drive components must be appropriately sized, which increases the lift table's weight and acquisition costs.
Energy requirement for raising and lowering
In a spindle lift table, the lifting spindle must be powered for both lifting and lowering. Unlike hydraulic lift tables, energy is required in both directions of movement.
High requirements for process quality
When using a ball screw spindle instead of a trapezoidal spindle, the requirements for process quality are particularly high. The lift table manufacturer’s design must ensure that no forces are applied to the spindle perpendicular to the direction of movement. Otherwise, this would result in the destruction of the drive components, as the ball screw spindle can only handle axial forces.
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