DE3707967A1 - ELECTRIC WATER HEATER - Google Patents

Description

The invention relates to an electric instantaneous water heater according to the Preamble of claim 1.

From DE-AS 11 79 314 is an electric instantaneous water heater Kind known in which controlled by a water switch Multi-pole operating switch contact device with the heating circuit Initiation of the tapping process is closed. The multipole Switch contact device consists of a triple Snap spring contact arrangement, which is connected to the water switch via a Actively connected lever system is operated.

A safety switch for a water heater The aforementioned type is known from DE-AS 15 40 906 and 22 58 850.

In the operating switch contact device and Safety switching device is two completely separate Units or components of the instantaneous water heater, the one corresponding effort in production and in the use of materials and Require time in final assembly.

The invention has for its object the above Reduce effort and a structurally simplified Switching device for a water heater of the type mentioned to accomplish.

The solution to this problem according to the invention is the characteristic Part of claim 1 can be seen.

Advantageous further developments of the subject of the innovation are specified in the subclaims.  

The advantages achieved with the invention are compact and Space-saving training of the switching device can be seen in the two Switching functions (normal power switching and power isolating circuit in the event of a fault) are integrated.

An exemplary embodiment of the invention is shown in the drawing and is described in more detail below based on this.

Show it:

1 shows a combined operating switch contact and safety switching device,

Fig. 2 is a cutaway view of the safety switching device according to Fig. 1,

FIGS. 3a and 3b, in an enlarged detail view Doppelkontaktschnapp- the spring or the switching device combination.

In Fig. 1 of the drawing, ( 1 ) denotes the indicated differential pressure socket of a so-called water switch, not shown, which can be connected to the cold water supply line of an electrically heated instantaneous water heater for three-phase connection. Inside the differential pressure cell there is a lifting diaphragm which is raised by the differential pressure when water is drawn off and which raises or pushes a switching tappet ( 2 ). The switching plunger ( 2 ) works together with a lever system ( 3 ), which consists of a pivoted angle lever ( 4 ) and three pivoting, multi-arm switching levers ( 5 ). Each of the switching levers ( 5 ) works together with a snap spring ( 6 ) contacted and keeps the contact ( 7 ) in the open position when the instantaneous water heater is idle. The contacted snap spring ( 6 ) is part of a U-shaped one-piece snap spring contact arrangement ( 8 ), the other contacted snap spring ( 9 ) with its contact ( 10 ) through the lever arm ( 11 ) of another lever system ( 12 ) during normal operation in the circuit -Closed position is held. The lever system ( 12 ) is also pivotally mounted and is latched to a two-armed lever ( 14 ) held under the action of a spring element ( 13 ). One arm ( 14 ') of the two-armed lever ( 14 ) works with an electric magnet ( 15 ) which can be connected to an excess temperature, a safety switching device, while the other arm ( 14 '') is responsive to the occurrence of overpressure in the flow system of the water heater Overpressure protection ( 16 ) is affected.

The snap spring contact arrangement ( 8 ), three of which are required in a water heater with a three-phase connection, are held on an insulating support ( 17 ) and separated from one another by intermediate webs ( 18 , 18 '). The two U-legs of the snap or spring contact arrangement ( 8 ), of which one ( 6 ) carries the movable contact ( 7 ) of the operating switch contact device and the other ( 9 ) carries the movable contact ( 10 ) of the safety switching device, are flat Web ( 19 ) connected to each other. The contact arrangement ( 8 ) is fixed and fastened to the insulating support ( 17 ) with the flat web ( 19 ). The insulating support ( 17 ) practically represents the connecting part between the operating switch contact device on the one hand and the safety switching device on the other. In the manufacture of the U-shaped contact arrangement ( 8 ) from a rolled metal strip, it is particularly expedient that the snap or spring springs transversely to the rolling device of the Metal strip are placed or trained to run. As a result, the relaxation behavior (flexural fatigue strength) that works better in this direction is used.

The function of the device described is as follows: With a corresponding water flow rate, the lifting diaphragm in the differential pressure cell ( 1 ) is raised accordingly by the dynamic pressure that occurs, and the switching plunger ( 2 ) is thus brought upwards. The movement of the switching plunger ( 2 ) is transmitted to the angle lever ( 4 ), which thereby pivots about its fulcrum and thereby also pivots the switching lever ( 5 ) which is operatively connected to it about its fulcrum. The contacted snap spring ( 6 ) of the contact arrangement ( 8 ) is relieved and goes into the closed position with the stationary counter contact ( 7 '). The heating circuit for the instantaneous water heater is now closed. In the event of a malfunction or catastrophe, the two-armed lever ( 14 ) of the safety switching device is actuated either by the overpressure safety device ( 16 ), which responds to overpressure, or by the electro-magnet ( 15 ) that maintains voltage at overtemperature, which causes the movable contact ( 10 ) Snap spring ( 9 ) with the stationary counter contact ( 10 ') in the closed position holding lever system ( 12 ) is triggered and the snap spring ( 9 ) with its contact ( 10 ) snaps into the open contact position or jumps.

Claims (7)

1.Electric instantaneous water heater, in particular for three-phase connection, with a multi-pole operating switching contact device closing the heating circuit when the tapping process is initiated and a safety switching device which interrupts the heating circuit at all poles, the operating switching contact device being actuated by means of a water switch which responds to differential pressure and the safety switching device is triggered when an overpressure or overpressure occurs , characterized in that the operating switching contact device and the safety switching device are combined into a single switching or structural unit and that a common double snap spring contact arrangement ( 8 ) is provided for both devices. 2. instantaneous water heater according to claim 1, characterized in that the snap spring contact arrangement ( 8 ) is integrally formed. 3. instantaneous water heater according to claim 1 or 2, characterized in that the contact arrangement ( 8 ) is U-shaped and has two springs ( 6 , 9 ), the one U-leg of this double spring contact arrangement ( 8 ) each having the movable contact ( 7 ) of the operating switch contact device and the other U-leg each carries the movable contact ( 10 ) of the safety switching device. 4. instantaneous water heater according to claim 2 or 3, characterized in that the two U-legs of the snap or spring ( 6 , 9 ) are interconnected by a flat web ( 19 ). 5. instantaneous water heater according to claim 4, characterized in that the snap or spring springs ( 6 , 9 ) with the flat web ( 19 ) on an insulating support ( 17 ) are fixed and attached. 6. instantaneous water heater according to claim 5, characterized in that the insulating body ( 17 ) is the connecting part between the operating switching contact device and the safety switching contact device. 7. instantaneous water heater according to claim 1 or one of the following, characterized in that the snap springs ( 6 , 9 ) of the U-shaped contact arrangement ( 8 ) are placed transversely to the production rolling direction.