Hydraulic system

• US 10,443,860 B2
• Filed: 12/16/2015
• Issued: 10/15/2019
• Est. Priority Date: 12/22/2014
• Status: Active Grant

• Current Assignee: Grundfos Holding A/S (POUL DUE Jensen's FOND)
• Original Assignee: Grundfos Holding A/S (POUL DUE Jensen's FOND)
• Inventors: Blad, Thomas, Blad, Christian
• Primary Examiner(s): Huson, Gregory L
• Assistant Examiner(s): Namay, Daniel E
• Application Number:
  US15/538,491
• Publication Number:
  US 20170336081A1
• Time in Patent Office: Days
• Field of Search: 237 8 A, 237 63, 237 65
• CPC Class Codes: F04D 13/06 the pump being electrically driven
• CPC Class Codes: F04D 13/0606 Canned motor pumps
• CPC Class Codes: F04D 15/0005 by using valves
• CPC Class Codes: F04D 15/0022 throttling valves or valves varying the pump inlet opening or the outlet opening
• CPC Class Codes: F04D 15/0066 by changing the speed, e.g. of the driving engine
• CPC Class Codes: F04D 29/4293 Details of fluid inlet or outlet
• CPC Class Codes: F16K 19/003 Specially adapted for boilers
• CPC Class Codes: F24D 19/1012 by regulating the speed of a pump
• CPC Class Codes: F24D 19/1066 for the combination of central heating and domestic hot water
• CPC Class Codes: F24D 3/08 in combination with systems for domestic hot-water supply
• CPC Class Codes: Y02B 30/70 Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Abstract

A hydraulic system includes at least one circulation pump assembly (2) provided with a speed controller (26), at least one hydraulic circuit (A, B) connected to the circulation pump assembly (2) as well as at least one mechanical switch device (86, 88; 120, 122) which is mechanically subjected to pressure by a fluid in the hydraulic circuit (A, B) and which can be moved into at least two different switch positions. The mechanical switch device (86, 88; 120, 122) moves by the circulation pump assembly (2) hydraulic coupling via the fluid. The speed controller is configured to initiate a movement of the switch device (86, 88; 120, 122), by at least one hydraulic force acting upon the switch device (86, 88; 120, 122) and causing a movement of the switch device (86, 88; 120; 122) via the hydraulic circuit, via a speed adaptation of the circulation pump assembly (2).

Claims

1. A hydraulic system comprising:

at least one circulation pump assembly provided with a speed controller;

at least one hydraulic circuit connected to the circulation pump assembly;

at least one mechanical switch device which is subjected to pressure from a fluid in the hydraulic circuit and which can be moved into at least two different switch positions, wherein the at least one mechanical switch device can be moved by the circulation pump assembly by way of a hydraulic coupling via the fluid, and the speed controller is configured to initiate a movement of the switch device by way of at least one hydraulic force acting upon the switch device and causing a movement of the switch device via the hydraulic circuit, via a speed adaptation of the circulation pump assembly;

another hydraulic circuit wherein the circulation pump assembly is connected to at least two hydraulic circuits and the at least one mechanical switch device is configured as at least one valve with at least two movable valve elements for changing a ratio of flows through the at least two hydraulic circuits, the at least one valve comprising at least one first and a second control surface, upon which a fluid pressure produced by the circulation pump assembly acts, wherein the first control surface is connected to the first valve element and the second control surface is connected to the second valve element such that the valve elements are movable by way of the forces acting upon the first and second control surface, the two valve elements having different dynamic characteristics such that the valve elements react differently to different pressure changes in the system.

2. A hydraulic system according to claim 1, wherein the mechanical switch device is configured such that the mechanical switch device reacts to pressure changes due to a speed change of the circulation pump assembly, such that the mechanical switch device can be selectively moved into one of the switch positions in dependence on the pressure or a change of the pressure.

3. A hydraulic system according to claim 1, wherein the mechanical switch device is configured such that the mechanical switch device reacts to differences in a course of a pressure build-up or pressure reduction of the fluid given a speed change of the circulation pump assembly, such that the switch device moves into a first switch position given a speed change of the circulation pump assembly with a first course of the pressure build-up, and into a second switch position given a speed change of the circulation pump assembly with a second course of the pressure build-up or pressure reduction which is different to this first course.

4. A hydraulic system according to claim 1, wherein the mechanical switch device is configured to be self-holding, such that the mechanical switch device remains in an assumed switch position up to a predefined speed change of the circulation pump assembly.

5. A hydraulic system according to claim 1, wherein the speed controller is configured such that at least two different speed courses of the circulation pump assembly can be set by the speed controller, wherein the speed controller is configured such that the circulation pump assembly permits speed changes with at least two different acceleration courses.

6. A hydraulic system according to claim 1, wherein the switch device is configured such that the movements into the at least two different switch positions are effected with different temporal delays, wherein the movements are effected along differently long paths and/or counter to differently large damping, inertia forces and/or biasing forces.

7. A hydraulic system according to claim 1, wherein the switch device is situated at an entry side of the hydraulic circuits.

8. A hydraulic system according to claim 1, wherein the switch device is arranged at the delivery side of the circulation pump assembly.

9. A hydraulic system according to claim 1, wherein the mechanical switch device is arranged on a suction side of the circulation pump assembly.

10. A hydraulic system according to claim 1, wherein the mechanical switch device is situated downstream of a first heat exchanger in the hydraulic system.

11. A hydraulic system according to claim 1, wherein the switch device is additionally subjected to gravitational force, to at least one magnet force and/or to at least one spring force, which acts in a direction of at least one movement axis of the switch device.

12. A hydraulic system according to claim 11, wherein the gravitational force, the magnet force and/or the spring force is directed opposite to a hydraulic force which acts upon the switch device and which is produced by the circulation pump assembly.

13. A hydraulic system according to claim 1, wherein the switch device is additionally subjected to gravitational force, to at least one magnet force and/or to at least one spring force, which acts in a direction of at least one movement axis of the switch device and in the idle position, each valve element is held in a defined first switch position by the gravitational force, the magnet force and/or the spring force, and the valve elements as well as the gravitational force, the magnet force and/or the spring force are configured such that one of the valve elements is moved by way of the fluid pressure firstly into a second switch position, in dependence on the course of the speed change of the circulation pump assembly.

14. A hydraulic system according to claim 1, wherein the first and the second valve element in their movement direction between the switch positions have differently large travels, are differently greatly damped and/or have inertia forces, friction forces and/or biasing forces which are counter to this movement direction and are differently large.

15. A hydraulic system according to claim 14, wherein at least one of the valve elements is provided with a delay device, wherein the delay device is configured such that fluid which flows through the valve along this valve element effects the delay.

16. A hydraulic system according to claim 15, wherein the delay device has a valve gap which extends transversely to a movement axis of the valve element between the valve element and a valve seat and which can be changed in gap width by way of a movement of the valve element along the movement axis.

17. A hydraulic system according to claim 16, wherein the valve gap is closed in one switch position.

18. A hydraulic system according to claim 1, wherein at least one valve with one of the valve elements is configured such that the valve element with movement along a movement axis, departing from a first switch position firstly closes by a certain amount and thereupon opens further.

19. A hydraulic system according to claim 1, wherein the first and the second valve element are coupled such that always only one valve element can be located in an opened switch position or always only one valve element can be located in a closed switch position.

20. A hydraulic system according to claim 19, wherein the movement axes of the first and of the second valve element run angled to one another.

21. A hydraulic system according to claim 19, wherein the movement axes of the first valve element and of the second valve element are perpendicular to one another.

22. A hydraulic system according to claim 1, wherein the hydraulic system is configured as a hydraulic heating and/or cooling system, wherein of the at least two hydraulic circuits, a first hydraulic circuit runs through an object to be temperature-controlled and a second hydraulic circuit runs through a secondary heat exchanger for the temperature control of service water.

23. A hydraulic system according to claim 22, wherein the switch device comprises a first valve element in the first hydraulic circuit running through the object to be temperature-controlled, and a second valve element in the second hydraulic circuit running through the secondary heat exchanger, wherein the first valve element in a first movement direction is biased with a lower force than the second valve element, and in an opposite movement direction the first valve element is more greatly damped or delayed in movement than the second valve element.

24. A hydraulic system according to claim 1, wherein the circulation pump assembly and the at least one switch device are arranged in a common construction unit comprising an integrated hydraulic construction unit for a compact heating installation.

25. A hydraulic system according to claim 22, wherein a valve element of the switch device in the first hydraulic circuit has a perpendicular movement axis, and a valve element in the second hydraulic circuit has a horizontal movement axis, wherein the horizontal movement axis extends parallel to a rotation axis of the circulation pump assembly.

26. A hydraulic system according to claim 1, wherein the first valve element comprises a first valve element spring having a first valve element spring constant, the second valve element comprising a second valve element spring having a second valve element spring constant, wherein one of the first valve element spring constant and the second valve element spring constant is less than another one of the first valve element spring constant and the second valve element spring constant.

27. A hydraulic system according to claim 1, wherein the first valve element and the second valve element are movable relative to each other.