JPH0655191B2 - Heating element such as electric water heater - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a heating element used in an electric water heater or the like for heating and keeping the contained liquid.

2. Description of the Related Art As a conventional heating element such as an electric water heater of this type, a heating element disclosed in, for example, JP-A-59-144417 is known.

This is a pair of left and right substrates 10 as shown in FIG. 8 and FIG.
The main heating wire 102 for high heat generation and the heat-retaining heating wire 103 for low heat generation are wound in two lines with one wire on each of
Insulating plates 104 and 105 are provided on both side surfaces of the main body 1, and the main heating wire 102 and the heat retaining heating wire 10 are provided on the side opposite to the mounting surface.
3 is pulled out, and the pull-out portion 106 is connected to the plurality of insulators 1.
In addition to covering with 07, the surface on the side opposite to the lead-out portion 106 was held in close contact with the heat transfer plate 108.

Problems to be Solved by the Invention In such a conventional configuration, the main heating wire 102 for high heat generation and the heat retention heating wire 103 for low heat generation are provided on the pair of left and right substrates 101.
Since it is a work of winding each one of the wires, it is good until one of the heating wires is wound on one board, but if you try to continue winding on the other board, the finished board becomes an obstacle. Workability is poor and both substrates 10
There is a problem that the heating wire is bent, broken, or loosened in the section A, which is the bridging section of No. 1, which greatly affects the performance and durability. Further, since the length of the heating wire is long, it is difficult to perform the work, and the cost of defective products is greatly affected.

The present invention solves the above-mentioned conventional problems, and can provide a heating element such as an electric water heater or the like that can significantly improve workability, is excellent in performance and durability, and is also advantageous in cost. It is intended.

Means for Solving the Problems In order to solve the above problems, the present invention separately wraps a pair of opposed substrates which are substantially symmetrical to each other, after winding a main heating wire having a rectangular cross section for heating a contained liquid, While passing the winding end of one end through the positioning holes provided in the pair of facing substrates,
A plurality of connection holes are provided between the positioning holes, both ends of the connection holes are spot-welded, and the other ends are appropriately pulled out, and both side surfaces of the substrate are covered with insulating plates to form a heat transfer plate. It is a pressure-bonded structure.

Action According to the above configuration, since the main heating wire can be separately wound around each substrate, the workability is good and the cost is also advantageous. Further, since the connection between the substrates is performed after the winding work, there is no problem such as bending, disconnection, or looseness of the heating wire, and the performance and durability are excellent.

Embodiment One embodiment of the present invention will be described below with reference to the accompanying drawings.

1 to 7, reference numeral 1 denotes a heat transfer plate having a central portion protruding upward in a substantially D shape to form an outer peripheral side edge 1a. The heat transfer plate 1 is a D-cut peripheral side portion. The temperature detection surface 1c is provided on the lower surface of the rim 1b, and the outer edge portion is airtightly fixed to the lower end of the cylindrical body by means such as welding to form the metal container 2. Reference numeral 3 is an exterior body that wraps the container 2 through a space.

On the lower surface of the heat transfer plate 1, a pair of left and right substrates 6 having a main heating wire 4 for boiling water and a heat-retaining heating wire 5 for heat retention wound in two strips are laminated between the upper and lower insulating plates 7 and 8. The first heat diffusion plate 9 having good heat conductivity is disposed on the upper surface of the upper insulating plate 7. The substrate 6 has a through hole in the center thereof, and the substrate 6 has a second heat diffusion plate 10 having a good thermal conductivity and a backing material 11 on the lower surface of the heat transfer plate 1 so as to provide a pressing margin. The heating element portion 12 is formed by being fixedly incorporated by spot welding or the like.

The main heating wire 4 and the heat-retaining heating wire 5 are wound around the substrate 6 of the heating element portion 12 after they are wound around different substrates 6 and then both substrates 6 are wound.
As shown in FIG. 5, the main heating wire 4 penetrates the winding ends 4a of the main heating wire 4 into the positioning holes 6a provided in the facing substrates 6, and then the main heating wires 4 are placed between the positioning holes 6a. A plurality of (2 to 3) connecting holes 6b are provided, and spot welding is performed here to join them.

As shown in FIG. 6, the heat retaining heating wire 5 is provided with L-shaped groove portions 6c at opposite ends of the substrate 6, and after winding the end portion of the heat retaining heating wire 5 around the groove portion 6c, both substrates 6 are wound. Groove 6c
The spaces are connected by a connecting member 13 made of a material having good electrical conductivity.

Numerals 14 and 15 are terminal plates which are provided on the opposite side of the connecting portion of the both heat generating wires 4 and 5 and constitute a lead-out portion. The terminal plates 14 and 15 are the main heat generating wire 4 and the heat retaining heat generating wire 5.
Are connected together and a terminal plate B15 is connected individually. The terminal plates A, B14, 15 and the main heating wire 4, the heat retaining heating wire 5
The heating wires 4 and 5 are arranged on the mounting holes 6a provided on the substrate 6, and the mounting surfaces 14a and 15a of the terminal plates A, B14 and 15 are positioned on the heating wires 4 and 5 to form a connection. We are welding.

Reference numeral 16 is a terminal pottery which insulates and holds the terminal plates A, B 14 and 15. Reference numeral 17 is a temperature-sensitive reed switch that is held in pressure contact with the temperature detection surface 1c. The temperature-sensitive reed switch 17 is a good conductor of heat and is integrated with the temperature fuse 18. Reference numeral 19 denotes a temperature controller provided in the center of the heat transfer plate 1, which is closely held by a spring or the like. The main heating wire 4 is electrically connected to the temperature controller 19, and the heat retention heating wire 5 is electrically connected to the temperature-sensitive reed switch 17 to form a parallel circuit. Further, the temperature fuse 18 is connected in series to form an electric water heater. is doing.

Next, the operation of the above configuration will be described. When water is poured into the container 2, the temperature of the water is detected by the temperature controller 19 and the temperature sensitive reed switch 17, and the main heating element 4 and the heat retaining heating element 5 are energized. Due to these heat generation, the hot water temperature rises. When the boiling water boiled, the temperature controller 19 turns off.
After that, the temperature-sensitive reed switch 17 controls the heat-retaining exothermic wire 5 to maintain a constant boiling temperature.

Here, since the main heating wire 4 of the heating element portion 12 is separately wound around the pair of left and right substantially symmetrical substrates 6, the workability is good and the cost is also advantageous.

In addition, the connection between the substrates 6 is such that the winding end 4a of the main heating wire 4 is passed through the positioning holes 6a provided in the facing substrates 6 and a plurality (2 to 3) of connections are made between the positioning holes 6a. Hole 6
Since it is only necessary to provide b and perform spot welding at the connecting hole 6b, a simple and reliable product can be obtained. As a result, twisting, bending, disconnection, etc. at the bridging part during conventional winding work Alternatively, there is no problem of sagging, and the performance and durability are excellent.

EFFECTS OF THE INVENTION As is clear from the description of the above embodiment, the heating element such as the electric water heater of the present invention has various excellent effects as follows.

(1) Since the main heating wire is separately wound around a pair of left and right substantially symmetrical substrates, workability is good, and cost is also advantageous.

(2) Since the connection between the pair of substrates is performed after the winding work, there is no problem such as twisting or bending during the winding work, disconnection or looseness during assembly, and the performance and durability are excellent.

(3) To connect a pair of boards, simply pass the winding end of the main heating wire through the positioning holes provided in the facing boards, and spot weld the connecting holes between the positioning holes. It's good, so you can get something simple and reliable.

(4) Since the winding work is performed for each substrate on one side, it is easy to develop the automatic winding.

[Brief description of drawings]

1 is a sectional view of an electric water heater using a heating element showing an embodiment of the present invention, FIG. 2 is an exploded perspective view of the heating element, and FIG. 3 is a partially cutaway plan view of the heating element. FIG. 4 is a partial sectional view of the same heating element, FIG. 5 is a sectional view of a joint portion of the main heating wire, FIG. 6 is a perspective view of a joint portion of the heat retaining heating wire, and FIG. 7 is the same heating wire. FIG. 8 is a cross-sectional view of a conventional heating element, and FIG. 9 is a plan view showing a winding state of the heating element. 1 ... Heat transfer plate, 4 ... Main heating wire, 4a ... Winding end, 6 ...
Substrate, 6a ... Positioning hole, 6b ... Connecting hole, 7,
8 ... Insulation plate.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuhiro Hirata 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Osamu Ohno 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. 72) Inventor Yasuhisa Tanaka 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (1)

[Claims] 1. A positioning member provided on a pair of substrates facing each other after winding a main heating wire having a rectangular cross-section for heating a contained liquid separately on a pair of left and right symmetrically facing substrates separately. Along with penetrating the hole, a plurality of connecting holes are provided between the both positioning holes, both ends of the connecting hole are spot-welded, and the other end is appropriately pulled out, and both side surfaces of the board are insulated. A heating element such as an electric water heater, which is covered with and is pressed against a heat transfer plate.