Swash plate angle sensor
View Patent ↗The invention is directed to a swashplate angle sensor ( 10 ) for a variable displacement hydraulic unit ( 1 ). The hydraulic unit ( 1 ) comprising a housing ( 2 ), within which a swashplate ( 3 ) with a rod shaped feedback-link ( 12 ) fixedly attached to the swashplate ( 3 ) is arranged pivotable around a swashplate axis ( 7 ). The angle sensor ( 10 ) comprising a magnet ( 16 ) mounted rotatable on a magnet carrier ( 13 ), and a sensor ( 15 ) for sensing the orientation of the magnet ( 16 ). The magnet carrier ( 13 ) is located in a control block ( 14 ) attached to the housing ( 2 ) and is located parallel to the feedback-link ( 12 ). The magnet carrier ( 13 ) is rotatable around a sensor axis ( 18 ) being parallel to the swashplate axis ( 7 ). A linkage spring ( 11 ) provides a connection between the feedback-link ( 12 ) and the magnet carrier ( 13 ) such that a pivoting of the swashplate ( 3 ) with the feedback-link ( 12 ) causes a rotation of the magnet carrier ( 13 ).
1. A swashplate angle sensor for a variable displacement hydraulic unit comprising a pivot-able swashplate with a rod shaped feedback-link attached thereon, the angle sensor comprising a magnet mounted on a magnet carrier rotatable around a sensor axis, and a sensor for sensing the orientation of the magnet, wherein
the angle sensor comprises a linkage element providing a mechanical linkage between the feedback-link and the magnet carrier such that a pivoting of the swashplate moves the linkage element via the feedback-link and causes a rotation of the magnet carrier.
2. The swashplate angle sensor of claim 1 , wherein the linkage element comprises a spring with a U-shaped elongated hole-section surrounding the feedback-link in a tight slide-able contact therewith, and with two legs, the ends of which are coupled to the magnet carrier.
3. The swashplate angle sensor of claim 2 , wherein the length of the elongated hole-section of the linkage element is greater than the adjoining diameter of the feedback-link.
4. The swashplate angle sensor of claim 3 , wherein the ends of the linkage element protruding from the magnet carrier are bent at an angle, wherein the angle is greater than or equal to 90°.
5. The swashplate angle sensor of claim 3 , wherein the linkage element is a linkage spring of torsional type with a rectangular, round or oval cross-section.
6. The swashplate angle sensor of claim 3 , wherein the ends of the linkage element are in slide-able contact with an inner wall of the control block.
7. The swashplate angle sensor of claim 2 , wherein the ends of the linkage element protruding from the magnet carrier are bent at an angle, wherein the angle is greater than or equal to 90°.
8. The swashplate angle sensor of claim 2 , wherein the linkage element is a linkage spring of torsional type with a rectangular, round or oval cross-section.
9. The swashplate angle sensor of claim 2 , wherein the ends of the linkage element are in slide-able contact with an inner wall of the control block.
10. The swashplate angle sensor of claim 1 , wherein the linkage element comprises an elongated hole-section surrounding the feedback-link in a tight slide-able contact therewith, and an adjoining leg, the end of which is coupled to the magnet carrier.
11. The swashplate angle sensor of claim 10 , wherein the length of the elongated hole-section of the linkage element is greater than the adjoining diameter of the feedback-link.
12. The swashplate angle sensor of claim 1 , wherein the ends of the linkage element protruding from the magnet carrier are bent at an angle, wherein the angle is greater than or equal to 90°.
13. The swashplate angle sensor of claim 12 , wherein the linkage element is a linkage spring of torsional type with a rectangular, round or oval cross-section.
14. The swashplate angle sensor of claim 12 , wherein the ends of the linkage element are in slide-able contact with an inner wall of the control block.
15. The swashplate angle sensor of claim 1 , wherein the linkage element is a linkage spring of torsional type with a rectangular, round or oval cross-section.
16. The swashplate angle sensor of claim 15 , wherein the ends of the linkage element are in slide-able contact with an inner wall of the control block.
17. The swashplate angle sensor of claim 1 , wherein the ends of the linkage element are in slide-able contact with an inner wall of the control block.
18. The swashplate angle sensor of claim 1 , wherein the sensor axis and/or the longitudinal axis of the magnet carrier is parallel to the longitudinal axis of feedback-link and/or to the swashplate pivot axis.
19. The swashplate angle sensor of claim 1 , wherein the magnet carrier is situated in a housing or in a control block of the hydraulic unit.
20. A control block of a variable displacement hydraulic unit comprising a swashplate angle sensor suitable to be fixed on a housing of the variable displacement hydraulic unit and suitable to be coupled to a feedback link of the variable displacement hydraulic unit, the variable displacement hydraulic unit comprising a pivot-able swashplate with a rod shaped feedback-link attached thereon, the swashplate angle sensor comprising a magnet mounted on a magnet carrier rotatable around a sensor axis, and a sensor for sensing the orientation of the magnet, wherein
the swashplate angle sensor comprises a linkage element providing a mechanical linkage between the feedback-link and the magnet carrier such that a pivoting of the swashplate moves the linkage element via the feedback-link and causes a rotation of the magnet carrier.