JP2000136885A - Geared motor for hot water supply machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve durability, increase torque, and improve magnetic noise resistance by forming a rotary shaft of a DC motor for driving a valve for a hot water supply machine with the torque transmitted from a transmitting part by an iron material, and supporting one end thereof by a resin made receiving part arranged on a case. SOLUTION: When a DC motor 1 is driven by a control signal from an outside control circuit, its rotation is transmitted to a rotary shaft 2, a warm gear 3, and the like in order, and a valve for the hot water supply machine is driven by a knurled groove part of an output gear. In this case, a rotary shaft 2 of the DC motor 1 is formed longer by an iron material such as, for example, SUS, bearing steel, and SK material. A tip end part of the rotary shaft 2 is supported by a resin made receiving part 12A made of, for example, polyacetal, nylon, and the like which is arranged on a lower case 12. A load torque to the warm gear 3 is increased, and a supporting part is prevented from abrading at once by force generated in a horizontal direction of the warm gear 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a geared motor for opening and closing a valve for controlling a hot water temperature of a gas or oil hot water heater.

[0002]

2. Description of the Related Art A valve of a water heater for controlling the temperature of a gas or oil water heater has unstable factors such as a problem of sticking after being left for a long period of time, a scale, and an increase in load due to fluctuations in water pressure. The requirements for geared motors for opening and closing valves are becoming stricter year by year.

FIG. 9 shows a conventional example of a geared motor for opening and closing a valve for controlling the temperature of a gas or oil water heater.
Shown in In FIG. 9, reference numeral 1 denotes a DC motor with a brush, which is rotated by a control signal from an external control circuit, and its rotational force is transmitted to the worm gear 3 through the rotating shaft of the DC motor 1 and further through other gears. After the torque is transmitted, power is transmitted to the valve of the water heater via the output gear, and the valve is driven.

The DC motor 1, the first worm gear 3 and the like are arranged on the lower case 12, and a tip 3A formed integrally with the first worm gear 3 is provided on the lower case 12. It is supported by the portion 12A. At this time, as the required specification of the load torque of the output gear that outputs power to the valve of the water heater increases, the load torque on the worm gear 3 also increases, and the force with which the worm gear 3 escapes in the horizontal direction increases. Therefore, there is a problem in that the tip portion 3A and the receiving portion 12A, which are made of resin, are quickly worn away.

Also, as described above, the first worm gear 3
, The torque is transmitted through other gears, and the power is transmitted to the valve of the water heater through the output gear. At this time, a plurality of gears for transmitting the rotation from the worm gear 3 to the output gear are provided. The shafts of the respective gears are supported by a lower case in which they are arranged and an upper cover that covers the lower case.

However, as shown in the side sectional view of FIG. 10, with respect to the fifth gear 7 for transmitting rotation to the above-mentioned output gear, its gear shaft 11A is composed of a lower case 12 and an upper cover 1.
3 is supported by an intermediate plate 14 and an upper cover 13 provided in the middle of the intermediate member 3. At this time, when the load torque described above is small, this structure is sufficient,
Problems have arisen as the load torque increases.

That is, when the load torque of the output gear increases, a counterclockwise or leftward load torque is applied to the fifth gear 7 according to the rotation direction as a reaction, and the force acts on the fifth gear shaft 11A, and The force acting on the fifth gear shaft 11A is applied to the upper cover 13 and the middle plate 14. Middle plate 1
When a force is applied to the fourth gear 4, the intermediate plate 14 moves in accordance with the force, and the meshing pitch between the gear (not shown) that transmits the rotation to the fifth gear 7 and the fifth gear 7 is out of order. Or, the mesh escaped, and the desired torque was not generated.

In addition, since the control unit of the water heater has been reduced in size, it is not uncommon to dispose an electromagnetic valve in the immediate vicinity of the geared motor, and the leakage magnetism of the electromagnetic valve adversely affects the Hall IC of the geared motor. do it,
A malfunction phenomenon of malfunctioning has also occurred.

[0009]

As described above, conventional geared motors for water heaters have the problem of component durability.
There is a problem that a desired torque cannot be obtained, and a problem that the leakage magnetism affects the Hall IC.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a geared motor for a water heater, which has improved performance and quality such as improved durability, increased torque and improved magnetic noise resistance. Is to do.

[0011]

According to the present invention, there is provided a DC motor driven by an external control signal, and a worm provided on a rotating shaft of the DC motor and rotating with the rotation of the rotating shaft. A gear, a transmission unit for transmitting rotation of the worm gear, and a case in which the DC motor, the worm gear, and the transmission unit are arranged, and a valve of the water heater using the rotational force transmitted by the transmission unit. A geared motor for a water heater configured to drive the rotating shaft, wherein the rotating shaft is made of an iron-based material,
One end thereof is supported by a resin receiving portion provided on the case.

Further, a support member for preventing the movement of the worm gear in the direction of the receiving portion is provided between the worm gear and the receiving portion.

A DC motor driven by an external control signal; a transmission unit for transmitting the rotation of the DC motor; a case in which the DC motor and the transmission unit are arranged; a cover for covering the case; A geared motor for a water heater that is configured to drive a valve of the water heater through an output gear by the rotational force transmitted by the transmission unit, wherein the transmission unit includes a plurality of gears, at least the A shaft of a preceding gear transmitting torque to the output gear and a shaft of a gear transmitting torque to the preceding gear are fixed by the case and the cover.

Further, there is provided a DC motor which rotates by a control signal from the outside, and a geared motor for a water heater which transmits the rotational force of the DC motor and drives a valve of the water heater via an output gear. A Hall IC for detecting a position of the output gear in the rotation direction, and a shield plate having a bent portion bent so as to surround the Hall IC and shielding external magnetism to the Hall IC. It is characterized by.

[0015]

(Embodiment 1) An embodiment of the present invention will be described with reference to the drawings. 2 and 3 are views showing the structure of a geared motor for a water heater according to the present invention, and FIG.
FIG. 2B is a top view, FIG.
FIG. 4 is a side sectional view, and FIG. 4 is a developed side view of a gear train showing the order of transmission of rotational force by gears of the geared motor for a water heater according to the present invention.

In FIGS. 2, 3 and 4, reference numeral 1 denotes a brushed DC motor which is a drive source of a geared motor for a water heater according to the present invention, and reference numeral 2 denotes a rotating shaft of the DC motor 1. Reference numeral 3 denotes a first worm gear, which is integrally fixed to the rotating shaft 2 by means of press fitting or the like, and rotates with the rotation of the rotating shaft 2, and the rotation of the first worm gear 3 is the second gear 4 and the third gear. The fifth gear, the fifth gear 6, the fifth gear 7, and the output gear 8 are configured to mesh with each other so as to be transmitted in this order.

At this time, the second gear 4 and the fourth gear 6 are rotatably supported on the second gear shaft 9, respectively. The third gear 5 is on the third gear shaft 10, and the fifth gear 7 is on the third gear shaft 10. The fifth gear shaft 11 is rotatably supported by the fifth gear shaft 11. The second gear 4, third gear 5, fourth gear 6, and fifth gear 7 constitute a transmission unit.

Reference numeral 12 denotes a lower case corresponding to a case in which the DC motor 1, the first worm gear 3, each gear and the like are arranged, and an upper cover 13 corresponding to a cover covered on the lower case 12 and a lower cover 12. A housing is constituted by the case 12. A Hall IC 16 is mounted on the printed circuit board 15 to detect the position of the output gear 8 in the rotation direction, and a magnet 17 is installed on the output gear 8 to detect the position of the output gear 8 in the rotation direction. A sensor is constituted by the IC 16 and the magnet 17.

Reference numeral 18 denotes an iron-based sheet material such as a silicon steel sheet, and a plurality of bent portions 1 as described later.
8A is a shield plate for reducing the magnetic influence on the Hall IC 16, and the printed board 15 and the shield plate 18 are fixed by screws 19.

Reference numeral 14 denotes an intermediate plate that presses the DC motor 1 from above and positions and fixes the printed circuit board 15 and the shield plate 18, and rotatably supports one end of the output gear 8. Reference numeral 20 denotes a lead wire for supplying power to the DC motor 1 and extracting a signal from the Hall IC 16. Note that the same components as those in the conventional example of FIGS. 9 and 10 are denoted by the same reference numerals.

Now, power is supplied to the DC motor 1 by a control signal from an external control circuit, and the DC motor 1
Is driven, as shown in the developed side view of FIG.
The rotation of the C motor 1 is the rotation shaft 2 → the first worm gear 3 →
The second gear 4 → the third gear 5 → the fourth gear 6 → the fifth gear 7 → the output gear 8, and the power is transmitted to the valve of the water heater by the knurled groove 8 </ b> A of the output gear 8 to move the valve.

As described above, the sensor for knowing the opening degree of the valve is composed of the magnet 17 and the Hall IC 16, and one magnet and two or three Hall ICs are used. At this time, by changing the arrangement of the Hall IC 16, a desired control angle can be achieved.

Also, as shown in the top view of FIG. 1, in this embodiment, unlike the conventional example of FIG. 9, the rotating shaft 2 of the DC motor 1 is elongated, and the tip of the first worm gear 3 shown in FIG. The end portion of the rotating shaft 2 is supported by a resin receiving portion 12A made of, for example, polyacetal, nylon, PBT, or the like provided on the lower case 12 in a shape without the portion 3A.

Thus, the distal end 3A of the first worm gear 3 made of resin is not supported by the receiving portion 12A made of resin, but is made of, for example, SUS, bearing steel, SK material, or the like.
Since the tip of the rotating shaft 2 made of an iron-based material such as SUM is supported, the load torque on the first worm gear 3 increases, so that the first worm gear 3 moves in the direction of arrow G in FIG. There is no need to worry that the supporting portion will be quickly worn away due to the generated force.

As shown in FIG. 5, between the worm gear 3 and the receiving portion 12A, a washer 2 which is a support member made of a material resistant to sliding wear such as a polyslider.
The first worm gear 3 may be prevented from moving in the direction of the receiving portion 12A with the interposition of the first worm gear 3. Details are as shown in FIG. 6, and in FIGS. 5 and 6, the same components as those in FIG. 1 are denoted by the same reference numerals.

In the case where the shaft length and the play tolerance of the DC motor 1 are large, the dimension of the press fitting of the worm gear 3 is most restricted by the construction method so that the large tolerance of the DC motor 1 is not absorbed. There is a possibility that the shaft tip of the rotating shaft 2 does not contact the concave portion 12B of the receiving portion 12A, or the shaft tip and the receiving portion 12A may strike. Shaft tip of rotary shaft 2 and receiving part 12
If the concave portion 12B of A does not hit, a thrust in the direction of the concave portion 12B of the worm gear 3 is applied to a thrust receiving portion (not shown) inside the DC motor, which causes wear.

At this time, the above-mentioned washer 21 shown in FIGS. 5 and 6 prevents the first worm gear 3 from moving in the direction of the receiving portion 12A due to the thrust and prevents the members inside the DC motor 1 from being worn. Can be.

As shown in detail in the side view of FIG. 7, in the conventional example of FIG. 10, the fifth gear shaft 11A for supporting the fifth gear 7 is supported by the upper cover 13 and the middle plate 14. On the other hand, in the present embodiment, the fifth gear shaft 11 is extended, and the fifth gear shaft 11 is fixed by the upper cover 13 and the lower case 12. That is, the shaft of the fifth gear 7, which is a gear at the preceding stage that transmits torque to the output gear 8, is fixed by the upper cover 13 and the lower case 12.

As shown in FIG. 3, the second gear shaft 9, which is the fixed shaft of the fourth gear 6 transmitting the rotation to the fifth gear 7, is also fixed by the lower case 12 and the upper cover 13, so that the output gear 8, the load torque of the lower case 12
And the upper cover 13 moves, the mesh pitch of the fourth gear 6 and the fifth gear 7 does not change. Therefore, a desired torque can be obtained without any escape of meshing. The fifth gear shaft 11 is a stepped shaft in order to avoid interference with the rotating shaft 2 of the DC motor 1.

FIG. 8 is a drawing showing the shield plate 18.
8A is a top view, FIG. 8B is a side view of FIG. 8A as viewed from the direction b, FIG. 8C is a side view of FIG. 8A as viewed from the direction c, and FIG. FIG. 2 shows a side view as seen from the direction. The shield plate 18 has a plurality of bent portions 18.
A, the shielding effect is higher as the number of the bent portions 18A is larger, but the structure is such that interference with other parts is avoided in the assembled product. According to the experiment, the shielding effect is fair if it is in all four corners.

In FIG. 8 (c), the magnetism toward the arrow F is concentrated on the bent portion 18A of the shield plate 18, and the magnetic flux density at the portion E is reduced. Since the Hall IC 16 is a surface mount type as shown in FIG. 3, the Hall IC 16 is easily affected by up and down magnetism.
When the Hall IC 16 is arranged so as to surround the H.16, that is, in the portion E shown in FIGS. 8A and 8C, a shielding effect can be obtained.

[0032]

According to the first aspect of the present invention, one end of the rotating shaft made of an iron-based material of the DC motor is connected to the D shaft.
Since it is supported by the resin receiving portion provided on the case where the C motor and the like are arranged, the supporting portion is not immediately worn out, and the durability can be improved.

According to the second aspect of the present invention, the worm gear provided on the rotating shaft of the DC motor is prevented from moving in the direction of the receiving portion supporting one end of the rotating shaft of the DC motor. Since the support member is provided between the worm gear and the receiving portion, the movement of the worm gear in the direction of the receiving portion due to the thrust is prevented, so that the members inside the DC motor can be prevented from being worn.

Further, in the invention according to claim 3 of the present invention, the shaft of a gear at the front stage for transmitting torque to an output gear for outputting torque for driving a valve of the water heater, The shaft of the gear transmitting the rotational force to the gear is D
Since the C motor and the like are fixed by the case and the cover, even if the load torque of the output gear increases, the meshing pitch between the gears does not change, and the desired torque is obtained and the torque Communication is assured.

According to the fourth aspect of the present invention, there is provided a hall IC for detecting a position in the rotation direction of an output gear for driving a valve of a water heater, and a fold formed to surround the hall IC. And a shield plate for shielding the Hall IC from external magnetism, so that the influence of external magnetic noise on the Hall IC can be reduced.

[Brief description of the drawings]

FIG. 1 is a top view showing a support state of a rotating shaft of a DC motor of a geared motor for a water heater according to the present invention.

FIGS. 2A and 2B show the structure of the geared motor for a water heater according to the present invention, wherein FIG. 2A is a top view and FIG.

FIG. 3 is a side sectional view showing a structure of a geared motor for a water heater according to the present invention.

FIG. 4 is an exploded side view of a gear train showing an order of transmitting torque by gears of the geared motor for a water heater according to the present invention.

FIG. 5 is another top view showing a state of supporting a rotating shaft of a DC motor of the geared motor for a water heater according to the present invention.

FIG. 6 is a structural diagram showing details of a support unit in FIG. 5;

FIG. 7 is a side sectional view showing a supported state of a fifth gear shaft of the present invention.

8 (a) is a top view, FIG. 8 (b) is a side view as viewed from the direction b, FIG. 8 (c) is a side view as viewed from the direction c, and FIG. 8 (d) shows the structure of the shield plate 18 of the present invention. It is the side view seen from the direction.

FIG. 9 is a top view showing a support state of a rotating shaft of a DC motor of a conventional geared motor for a water heater.

FIG. 10 is a side sectional view showing a state where a conventional fifth gear shaft is supported.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 DC motor 2 Rotating shaft 3 First worm gear 12 Lower case 12A Receiving part

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02K 23/68 H02K 7/116 5H623 // H02K 7/116 11/00 B (72) Inventor Motohiro Higuchi Osaka 1048 Okadoma, Kamon, Fumonma-shi F-term (reference) Matsushita Electric Works, Ltd. BB01 QQ02 RR02 UA08 5H623 GG11 JJ06

Claims (4)

[Claims] 1. A DC driven by an external control signal.
A motor, a worm gear provided on a rotation shaft of the DC motor and rotating with the rotation of the rotation shaft, a transmission unit for transmitting rotation of the worm gear, and the DC motor, the worm gear and the transmission unit are arranged. And a geared motor for a water heater configured to drive a valve of the water heater by the rotational force transmitted by the transmission unit, wherein the rotation shaft is made of an iron-based material, and A geared motor for a water heater, wherein one end is supported by a resin-made receiving portion provided on the case. 2. The water heater according to claim 1, wherein a support member for preventing the worm gear from moving toward the receiving portion is provided between the worm gear and the receiving portion. For geared motor. 3. A DC driven by an external control signal.
A motor, a transmission unit for transmitting rotation of the DC motor,
A case where the DC motor and the transmission unit are arranged;
A cover for covering the case, wherein the gearbox motor for a water heater is configured to drive a valve of the water heater via an output gear by a rotational force transmitted by the transmission unit, wherein the transmission unit includes a plurality of transmission units. A gear of a preceding stage transmitting torque to at least the output gear, and a shaft of a gear transmitting torque to the preceding gear are fixed by the case and the cover. Geared motor for water heater. 4. A DC rotating by an external control signal.
A motor and a geared motor for a water heater configured to transmit a rotational force of the DC motor and drive a valve of the water heater via an output gear, wherein a hole for detecting a position of the output gear in a rotation direction is provided. IC
A geared motor for a water heater, comprising: a bent portion bent so as to surround the Hall IC; and a shield plate for shielding external magnetism to the Hall IC.