The ATOS DLKZOR is a direct-acting servo-proportional directional valve that combines several features typically found only in higher-cost servo valves. Understanding its structural design explains why it achieves precision normally associated with much more expensive closed-loop hydraulic components.
The valve uses a direct-acting spool with a sleeve construction. Unlike conventional proportional valves where the spool runs directly in the cast body bore, the DLKZOR incorporates a precision-machined sleeve that guides the spool. This sleeve design improves concentricity, reduces friction variation, and maintains consistent clearance over the valve's service life - all critical for stable, repeatable control.
A defining characteristic is the zero spool overlap. Standard proportional valves typically have 5-15% overlap at neutral position to prevent internal leakage. The DLKZOR's zero overlap means the spool lands exactly at the port edge with no dead zone. When combined with an LVDT position transducer that provides real-time spool position feedback, this zero-overlap geometry enables bidirectional flow control starting from the first micron of spool movement. The result is exceptional response sensitivity for position and pressure closed-loop applications.
The internal LVDT continuously monitors spool displacement and feeds this signal to the onboard digital driver. When paired with an external motion controller, the valve can maintain hydraulic cylinder positioning within 0.01 mm under controlled load conditions. The same architecture supports precise pressure control loops, maintaining system pressure with minimal overshoot during transitions.
The DLKZOR is available in ISO 4401 size 10, with maximum pressure ratings of 315 bar on the P, A, and B ports. Rated flow options include approximately 40, 75, and 130 L/min at a reference pressure differential of 70 bar. For engineers evaluating proportional valve options for injection molding, die casting, or precision press applications, the combination of sleeve construction, zero overlap, and integrated position feedback represents a practical balance between servo-level precision and proportional valve cost.
