Title of Invention

SOLENOID VALVE FOR A FLUID-REGULATING HEATING AND/OR COOLING SYSTEM

Abstract

The invention is based on a solenoid valve (10) for a fluid-regulated heating and/or cooling system having a valve housing (16) which has an inflow p\ssage (18), an outflow passage (20, 22), a return flow passage (98) and a bypass passage (24, 26) between the inflow passage (18) and the return flow passage (98), and having an electromagnetically switched valve element (32, 34) and bypass valve element (36, 38) which, together with an armature (86, 88) are mounted on a reciprocating rod (52, 54), and the valve element (32, 34) brings about the connection between the inflow passage (18) and the outflow passage (20, 22) and blocks it in an energized switched posit~on, while the bypass valve element (36, 38) controls the connection between the bypass passage (24, 26) and the return flow passage (98) in the de-energized switched position as a function of the delivery flow, and brings about the connection in the energized switched position. It is proposed to provide a plurality of valve units (12, 14) whose inflow passages (18) are connected to , one another.

Full Text

The invention is based on a solenoid valve for a fluid-regulated heating and/or cooling system. EP 0 653 990 Bl discloses such a solenoid valve. It is used in particular in fluid-regulated heat exchangers for heating and/or air conditioning systems in motor vehicles. It can be actuated in a cycled fashion as a function of temperatures in the heating and/or air conditioning system or a passenger compartment, the flow which is necessary for heating being determined essentially by the average time cross section. The time cross section is determined by the time integral of the effective opening cross section. A valve element of the solenoid valve is opened with respect to an outflow passage by the pressure of the fluid in an inflow passage and/or by a valve spring, and is closed by an energized solenoid of the solenoid valve in that said solenoid acts on an armature which is connected to a reciprocating rod. In addition, seated on the reciprocating rod, which is extended beyond the valve element, is a bypass valve element which controls a bypass passage which is arranged between the inflow passage and a return flow passage. The valve element and the bypass valve element are matched to one another and to a valve spring in such a way that when the solenoid is in a de-energized state the flow rate to the outflow passage is kept constant independently of a higher delivery volume of a pump. For this reason, the time cross section needs only to be regulated as a function of the temperature and not as a function of the delivery flow of the pump. The delivery flow of the pump, which is as a rule driven by an internal combustion engine, changes in fact with its drive speed, i.e. with the speed of the internal combustion engine. Advantages of the invention According to the invention, a plurality of valve units are provided whose inflow passages are connected to one another. They can be actuated separately and are assigned to various heat exchangers of a heater. As a result, a plurality of heating circuits for different points of a vehicle, for example for the driver"s side and front seat passenger"s side, can be separated and regulated independently of one another using simple means. In the de-energized state of the valve units, the flow rate to the outflow passages is kept constant independently of a higher inflow from the pump. Here, it is expedient that the effective diameters of the valve seats, of the valve elements and of the bypass valve elements and the force of their valve springs are matched to one another in such a way that the flow rate is identical at all the valve units in the de-energized state, and is maintained at the de-energized valve units even if individual valve units are energized. This avoids a situation in which the pressure in the system rises when the valves are closed, and pressure peaks occur. If the valve springs are configured in such a way that the bypass valve elements do not open until there is a predefined flow rate to the heat exchangers, for example at 1600 litres per hour, no losses of heating power occur in this delivery rate range of the pump, since the entire inflow to the valve units is passed on to the heat exchangers of a heater. According to one refinement of the invention, the valve units are arranged in a common valve housing. External connecting lines between the valve units can be dispensed with. In addition, as a result of internal connecting passages and bypass passages, the expenditure on connections is reduced and the rise in pressure is substantially smaller so that relatively small magnetic circuits can be used. As a result, the costs, the use of materials, the physical volume and the weight are reduced. The return flow passage of the solenoid valve can expediently be routed together with the return flow line of the heat exchangers of a heater in the solenoid valve itself by virtue of the fact that the return flow passage has a corresponding connection. If, due to local conditions on the vehicle, the return flow line has to be laid over a shorter or more suitable path, the return flow passage is connected to the return flow line at a suitable point outside the solenoid valve. In addition, it is expedient to provide separate valve chambers with the replaceable valve seats for one valve unit, or for all the valve units. In this way, the solenoid valve can be adapted to different applications with little expenditure by replacing the valve chambers and the valve seats. The valve seats are expediently manufactured from an elastomer. The elasticity and damping property of the material reduces the closing noise and wear on the valve elements. Accordingly the present invention provides a solenoid valve for a fluid-regulated heating and/or cooling system comprising a valve housing which has an inflow passage, an outflow passage, a return flow passage and a bypass passage between the inflow passage and the return flow passage, an electromagnetically switched valve element and bypass valve element which, together with an armature are mounted on a reciprocating rod, and the valve element brings about the connection between the inflow passage and the outflow passage and blocks it in an energized switched position, while the bypass valve element controls the connection between the bypass passage and the return flow passage in the de-energized switched position as a function of the delivery flow, and brings about the connection in the energized switched position, characterized in that a plurality of valve units are provided whose inflow passages are connected to one another. Further advantages emerge from the following description of the drawings. The drawings represent exemplary embodiments of the invention. The description and the claims contain numerous features in combination. The person skilled in the art will also expediently consider the features individually and combine them into further appropriate combinations. In said drawings: Fig. 1 shows a cross section through a solenoid valve according to the invention having two valve units, and Fig. 2 shows a section along the line II-II in Fig. 1 in which a reciprocating rod of the valve unit is illustrated in an intermediate position. Fig. 3 shows an installation diagram, and Fig. 4 shows a variant of Fig. 3. Description of the exemplary embodiments The solenoid valve 10 according to Fig. 1 and Fig. 2 is arranged in a primary flow line 106 between an internal combustion engine 116 and the heat exchangers 108, 110 of a heater. There are two valve units 12, 14, which are installed in a valve housing 16. The valve housing 16 has an inflow passage 18 which is common to both valve units 12, 14 and is connected to a pump 118 which is driven by the internal combustion engine 116. In addition, said housing 16 has two outflow passages 20, 22 which are connected to various heat exchangers 108, 110 of a heater. These are as a rule arranged at various points in the vehicle, for example on the driver"s side and the front seat passenger"s side. The valve units 12 and 14 are of identical design. They have a solenoid 74, 76 with a coil former 82, 84 and a magnetic core 78, 80. The solenoid 74, 76 is accommodated in a magnet pot 70, 72 which is attached to the valve housing 60 via a supporting wall 68. An armature 86, 88 is guided in an axially displaceable fashion in a guide bushing 94, 96 in the solenoid 74, 76. A lid 102, 104 closes off the guide bushing 94, 96 so that an armature space 90, 92, into which the armature 86, 88 penetrates to a greater or lesser extent depending on the switched position, is formed between the lid 102, 104, the guide bushing 94, 96 and the armature 86, 88. The magnetic circuit is formed by means of the magnetic core 78 or 80, the armature 86 or 88, the guide bushing 94 or 96, the magnet pot 70 or 72 and the supporting wall 68. The armature 86, 88 is attached, for example welded, to a reciprocating rod 52, 54. The reciprocating rod 52, 54 extends through the magnetic core 78, 80 and the supporting wall 68 into the valve housing 16 and through a valve chamber 40, 42 into a return flow chamber 28, 30. A diaphragm seal 60, 62, providing a seal to the valve housing 16 and bearing against the reciprocating rod 52, 54, is arranged on the supporting wall 68. The valve chamber 40, 42 is inserted into the valve housing 16 as a separate component and has, at its ends, valve seats 44, 48 and 46, 50, which are expediently also manufactured as separate components from an elastomer. As a result, the valve chamber 40, 42 with the valve, seats 44, 48 and 46, 50 can easily be replaced and adapted to the respective application. A spacing element 64, 66, into which the outflow passage 20, 22 opens, is provided between the valve chamber 40, 42 and the supporting wall 68. A valve element 32, 34, which interacts with the valve seat 44, 48, is seated on the reciprocating rod 52, 54 towards the outflow passage 20, 22, In addition, a bypass valve element 36, 38, which interacts with the valve seat 46, 50 and controls a bypass passage 24, 26, is seated on the end of the reciprocating rod 52, 54 facing the return flow chamber 28, 30. The common inflow passage 18 for both valve units 12 and 14 runs between the valve chambers 40 and 42 and cuts into them between the valve seats 44, 48 and 46, 50 over a sufficient part of their circumference. This brings about the connection between the two valve chambers 40 and 42. The valve elements 32 and 34 with their associated valve seats 44 and 48, and the bypass valve elements 36 and 38 with their associated valve seats 46 and 50 are, together with the associated valve springs 56 and 58, matched to one another in such a way that in the de-energized state of the solenoids 74 and 76 the valve elements 32, 34 are opened and they distribute uniformly between the outflow passages 20 and 22 the available volume flow which is delivered by the pump 118. If the volume flow rises beyond a predefined amount, the bypass valve elements 36 and 38 open counter to the force of the associated valve springs 56 and 58. As a result, the excess volume flow flows via the bypass passages 24, 26 and the return flow chambers 28 and 30 into the return flow passage 98. The return flow passage 98 has a port 100, this being a connecting line to the heat exchangers 108, 110 of a heater. The port 100 is expediently arranged offset with respect to the return flow passage 98 which brings about the connection to the pump 118 in order to achieve a sufficient connecting overlap in the dividing wall between the return flow chambers 28 and 30 when the passages have small cross sections. Fig. 2 shows the valve element 32 of the valve unit 12 in an intermediate position in which the predefined flow rate has been reached and is being kept constant. The illustration in Fig. 2 differs from the illustration in Fig. 1 in that the valve element 32 is completely opened and the bypass valve element 36 is closed. The flow rate of the individual valve units 12, 14 can be influenced as a function of temperature by actuating the solenoids 74 or 76 in a cycled fashion, individually or jointly. If a solenoid 74 or 76 is energized, the associated armature 86 or 88 is attracted by the magnetic core 78 or 80 counter to the force of the associated valve spring 56 or 58, and the corresponding valve element 32 or 34 closes, while the corresponding bypass valve element 36 or 38 opens. Fig. 1 shows the valve unit 14 in an energized state of the solenoid 76. In contrast, the solenoid 74 of the valve unit 12 is de-energized, the predefined flow rate not yet being exceeded, so that the valve element 32 is opened and the bypass valve element 36 is closed. In the exemplary embodiment according to Figs. 1 to 3, the return flow line 112 is routed from the heat exchangers 108, 110 of the heater via the solenoid valve 10, specifically via the port 100 and the return flow passage 98. Here, it may be expedient for the solenoid valve 10 to serve as a connection between separately routed return flow lines 122 and 124 by virtue of the fact that the return flow lines 122, 124 are connected to the return flow passage 98 via passages in the solenoid valve 10. Depending on the spatial arrangement of the heat exchangers 108, 110 of the heater, and on the arrangement of the solenoid valve 10 and of the internal combustion engine 116, it may be expedient that the return flow line 112 is not routed from the heat exchangers 108, 110 of the heater via the solenoid valve 10 but instead a return flow line 114 is laid to the internal combustion engine 116 over a shorter or more convenient path and is connected to the cooling system of said internal combustion engine 116 (Fig. 4) . In this case, the port 100 may be dispensed with and the return flow passage 98 is connected at a suitable point 120 of the vehicle to the return flow line 114 which leads from the heat exchangers 108, 110 of the heater to the internal combustion engine 116. ROBERT BOSCH GMBH; D-70442 Stuttgart Reference symbols 10 Solenoid valve 48 12 Valve unit 50 14 Valve unit 52 16 Valve housing 54 18 Inflow passage 56 20 Outflow passage 58 22 Outflow passage 60 24 Bypass passage 62 26 Bypass passage 64 28 Return flow chamber 66 30 Return flow chamber 68 32 Valve element 70 34 Valve element 72 36 Bypass valve element 74 38 Bypass valve element 76 4 0 Valve chamber 78 42 Valve chamber 80 44 Valve seat 82 46 Valve seat 84 Valve seat Valve seat Reciprocating rod Reciprocating rod Valve spring Valve spring Diaphragm seal Diaphragm seal Spacing element Spacing element Supporting wall Magnet pot Magnet pot Solenoid Solenoid Magnetic core Magnetic core Coil former Coil former 8 6 Armature 8 8 Armature 90 Armature space 92 Armature space 94 Guide bushing 96 Guide bushing 98 Return flow passage 100 Port 102 Lid 104 Lid 106 Primary flow line 108 Heat exchanger of a heater 110 Heat exchanger of a heater 112 Return flow line 114 Return flow line 116 Internal combustion engine 118 Pump 120 Position in vehicle 122 Return flow line 124 Return flow line WE CLAIM: 1. A solenoid valve (10) for a fluid-regulated heating and/or cooling system comprising a valve housing (16) which has an inflow passage (18), an outflow passage (20, 22), a return flow passage (98) and a bypass passage (24, 26) between the inflow passage (18) and the return flow passage (98), an electromagnetically switched valve element (32, 34) and bypass valve element (36, 38) which, together with an armature (86, 88) are mounted on a reciprocating rod (52, 54), and the valve element (32, 34) brings about the connection between the inflow passage (18) and the outflow passage (20, 22) and blocks it in an energized switched position, while the bypass valve element (36, 38) controls the connection between the bypass passage (24, 26) and the return flow passage (98) in the de-energized switched position as a function of the delivery flow, and brings about the connection in the energized switched position, characterized in that a plurality of valve units (12, 14) are provided whose inflow passages (18) are connected to one another. 2. The solenoid valve (10) as claimed in Claim 1, wherein the valve units (12, 14) are arranged in a common valve housing (16). 3. The solenoid valve (10) as claimed in Claim 2, wherein each valve unit (12, 14) has a valve chamber (40, 42) which can be inserted into the valve housing (16) and which has, with respect to the outflow passage (20, 22) and return flow passage (98), one valve seat (44, 46; 48, 50) in each case, which valve seat (44, 46, 48, 50) interacts with the valve element (32, 34) and/or the bypass element (36, 38), and in that a common inflow passage (18) connects the valve chambers (40, 42) to one another. 4. The solenoid valve (10) as claimed in Claim 3, wherein the valve seats (44, 46) are produced from an elastomer. 5. The solenoid valve (10) as claimed in any one of the preceding claims, wherein the effective diameters of the valve seats (44, 46; 48, 50) and of the valve elements (32, 34) and of the bypass valve elements (36, 38), and the force of valve springs (56, 58) acting on the valve elements (32, 34, 36, 38), are matched to one another in such a way that the flow rate to the outflow passages (20, 22) at the de-energized valve units (12, 14) is identical at all the valve units (12, 14) independently of the instantaneous delivery rate of a pump (118), and in that this flow rate at the de-energized valve units (12) is maintained even if another valve unit (14) is energized. 6. The solenoid valve (10) as claimed in Claim 5, wherein the valve springs (56, 58) are provided such that the bypass valve elements (36, 38) of the de-energized valve units (12) do not open until a predefmed delivery rate of the pump (118) is reached. 7. The solenoid valve (10) as claimed in any one of the preceding claims, wherein a common return flow passage (98) is provided which connects return flow chambers (28, 30) of the valve units (12, 14) to one another. 8. The solenoid valve (10) as claimed in any one of the preceding claims, wherein a return flow line (112) of the heat exchangers (108, 110) of a heater is connected to a port (100) of the solenoid valve (10). 9. The solenoid valve (10) as claimed in any one of the preceding claims, wherein return flow lines (122, 124) are separated from the heat exchangers up to the solenoid valve (10) and are connected to the return flow passage (98) by means of passages within the solenoid valve (10). 10. A solenoid valve for a fluid-regulated heating and/or cooling system substantially as herein described with reference to the accompanying drawings.

Documents:

2577-mas-1998 abstract fig-1.jpg

2577-mas-1998 abstract-duplicate.pdf

2577-mas-1998 abstract.pdf

2577-mas-1998 claims-duplicate.pdf

2577-mas-1998 claims.pdf

2577-mas-1998 correspondence-others.pdf

2577-mas-1998 correspondence-po.pdf

2577-mas-1998 description(complete)-duplicate.pdf

2577-mas-1998 description(complete).pdf

2577-mas-1998 drawings-duplciate.pdf

2577-mas-1998 drawings.pdf

2577-mas-1998 form-1.pdf

2577-mas-1998 form-19.pdf

2577-mas-1998 form-26.pdf

2577-mas-1998 form-4.pdf

2577-mas-1998 petition.pdf