JP2834206B2 - Damper thermostat - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a damper thermostat that controls the temperature in a refrigerator by opening and closing a cold air intake port of a refrigerator.

2. Description of the Related Art In a refrigerator having a freezer compartment and a refrigerator compartment, cold air produced by an evaporator is sent into a refrigerator compartment through a duct. Here, the damper thermostat is attached to the duct opening, and the motor opens and closes when the temperature in the refrigerator rises, and closes when the temperature in the refrigerator falls. For example, Japanese Utility Model Application Laid-Open No. 61-23673 and Japanese Utility Model Application
The following describes the Dunbar Thermo disclosed in JP-A-205376. As shown in FIGS. 5 and 6, 1 is attached to the duct opening, and a housing having an opening 2 is a flap which can open and close the opening by rotatably operating the opening, and 4 urges the flap in a closing direction. It is a spring. 5 is an AC motor as a driving source,
Reference numeral 6 denotes a gear box for reducing the rotation of the motor 5, reference numeral 7 denotes a tilt cam interlocked with a gear, and reference numeral 8 denotes a pin which comes into contact with the tilt cam and opens and closes the flap 4.

The gear box 6 includes a motor output shaft 9, a first gear 10 meshing with the motor output shaft 9, and second gears 11 and 2 meshing with the first gear.
The third gear 12 has a gear portion 12a meshing with a number gear and a protrusion 12b having a large diameter portion and a small diameter portion, and the inclined cam 7 meshes with the third gear. 13 is a reed switch, 14 is a magnet, 15 is a magnet holding plate and a gear box 6
And the projection of the third gear 12 is always provided by a leaf spring 16.
It is urged to abut 12b.

The operation will now be described. The motor 5 rotates according to the temperature in the refrigerator, and the rotation is performed by the motor output shaft 9 and the first gear 1.
It is transmitted to the 0th and 2nd gears 11 and the 3rd gear 12 and transmitted to the inclined cam 7. Here, the tilt cam 7 rotates to rotate the pin 8
Can be converted into a linear motion, and the flap 3 can be displaced in the opening direction against the urging force of the spring 4 and can be displaced so as to be closed by the urging force of the spring 4. Here, it is necessary to stop the rotation of the motor 5 at the point where the flap 3 is opened and closed. For this reason, a projection 12b is provided on the third gear 12 that moves in conjunction with the inclined cam 7, and when the flap 3 is opened, the magnet holding plate 15 contacts the large diameter portion and the reed switch 13 is turned NO.
When the flap 3 is closed, the motor 5 is stopped by contacting the small diameter portion and turning off the reed switch 13.

Problems to be Solved by the Invention However, in the above configuration, there is a possibility that the open / close positions of the flap may vary due to the variation of each gear, magnet, and reed switch. In addition, parts such as a reed switch, a magnet, and a wiring board are required, so that there is a problem that it takes time to assemble. In addition, when the reed switch is mounted, trouble such as chipping of a glass tube occurs, and the contact is reliably opened and closed. However, there was a problem that was not sufficiently guaranteed.

According to the present invention, there is provided a tamper thermometer having a position detecting means, which accurately detects an open / close position of a flap and has a uniform opening / closing position due to a variation in each component, and is easy to assemble and surely contacts. It is to be convinced.

Means for Solving the Problems To solve the above problems, the present invention is provided in a cool air inflow duct, has an inlet portion and an outlet portion of the cool air, and is opened and closed by a blade of a rotary rotor between the inlet portion and the outlet portion. A housing having an opening having an opening, and a drive source for driving the rotor, two electrodes and a pressure-sensitive conductive rubber provided on the two electrodes are installed in the opening, and a wrong pressure-sensitive conductive rubber is provided on a blade of the rotor. It is characterized in that a metal part is provided which is in contact with the metal part.

The rotor driven by the drive unit contacts the opening,
When the opening is closed, the pressure-sensitive conductive rubber in the opening comes into contact with the metal part of the rotor, the two electrodes provided below the pressure-sensitive conductive rubber conduct, and a signal for stopping the driving of the driving unit is generated. generate.

Embodiment An embodiment of the present invention will be described with reference to FIGS. Reference numeral 20 denotes a rectangular housing having an annular concave portion 20a. The housing 20 has one bottom surface 21 and four side surfaces 22. One of the side surfaces has a cool air inlet 23, which communicates with the annular recess 20a.
It has two outlets 24a and 24b communicating with the annular concave portion 20a on a side surface perpendicular to 3. The annular recess 20a between the inlet 23 and the outlets 24a, 24b has two openings 25a, 25b at an angle of about 120 ° with respect to the respective outlets 24a, 24b. It is formed toward. Aperture
Each of the openings 25a and 25b includes an outer frame 26 and a window 27, and one of the openings has a recess 26a formed in the outer frame 26. The recess 26a is provided with two plate-shaped electrodes 28, A pressure-sensitive conductive rubber 29 is affixed on the top. The electrode 28 is connected to an external signal processing circuit (not shown).

The central part of the housing 20 has a cylindrical protrusion 30, and the protrusion 30 is hollow. Also, there is a recess 31 protruding from the annular recess 20a at an angle of about 60 ° with one opening 25a in the annular recess 20a of the housing 20, and the recess 31 similarly has a recess (not shown). Two electrodes (not shown) are formed therein, and a pressure-sensitive conductive rubber (not shown) is attached thereon. The electrodes (not shown) are also connected to an external signal processing circuit (not shown).

The hollow cylindrical protrusion 30 of the housing 20 has a DC motor 34 as a drive source and an output gear 34a.The motor 34 is mounted on the hollow cylindrical protrusion 30, and a disc-shaped base 36 holding a reduction gear 35.
Is stored, and the final stage 35a of the reduction gear 35 projects from the hole 30a of the cylindrical projection 30.

Further, a pin 37 is attached to the cylindrical projection 30 of the housing 20.
There is a rotor 38 rotatably mounted on the
38 is a cylindrical portion 38a holding the outer periphery of the cylindrical protrusion 30
And three rectangular blades 38b, 38c provided at an angle of about 120 ° to rotate in the annular concave portion 20a of the housing 20.
38D and a gear portion 38E provided inside the cylindrical portion 38a,
The gear portion 38E meshes with the final stage 35a of the reduction gear 35.
A high-density foam sealing material 39 for sealing is affixed to the blades 38b, 38c of the rotor 38, and is positioned to open and close the housing 20 openings 25a, 25b by rotation. The rest 38D of the blade portion is arranged so as to abut against the concave portion 31 of the housing 20.

Here, the blade portion 38b has an opening 25a of the housing 20.
A metal piece 40 having a sharp tip is embedded at a position where the metal piece 40 comes into contact with the pressure-sensitive conductive rubber 29 provided on the substrate. A metal piece 41 is embedded in the blade portion 38D at a position where the metal piece 41 comes into contact with a pressure-sensitive conductive rubber (not shown) provided in the concave portion 31 of the housing 20.

Further, a cover 42 covering the side facing the bottom surface 21 of the housing 20 is attached by screws 43. Note that a sealing foam (shown in the figure) is attached between the cover 42 and the housing 20.

Here, the operation of the embodiment of the present invention will be described. When the temperature in the refrigerator becomes lower than a predetermined temperature by a temperature sensor (not shown) in the refrigerator compartment, the motor 34 is connected to CH1 in the circuit of FIG.
With the drive signal, the motor 34 is connected to the rotor 38 via the reduction gear 35.
And the blades 38b, 38c of the rotor 38 rotate in a direction to close the two openings 25a, 25b provided in the annular concave portion 20a of the housing 20. Here, the pressure-sensitive conductive rubber 29 provided in the opening 25a comes into contact with the metal piece 40 provided in the blade portion 38b of the rotor 38, and when the rubber is pressed with a certain pressure, the pressure-sensitive conductive rubber 29 becomes conductive. Then, a signal current flows between the two electrodes 28, and as shown in the circuit of FIG. 4, the drive to the motor 34 is stopped and the motor 34 is held at the closed position. Conversely, when the temperature in the refrigerator becomes higher than the predetermined temperature, the motor 34 is connected to CH2 in the circuit of FIG.
The drive signal is input, and the motor 34 starts rotating in the opposite direction to the previous direction. At this time, the rotor 38 moves in a direction to open the openings 25a and 25b. And the third blade portion 38 of the rotor 38
The metal piece 41 of D comes into contact with the pressure-sensitive conductive rubber 34 of the concave portion 31 provided in the annular concave portion 20a of the housing 20 and is pressed by a certain pressure, thereby conducting between the two electrodes 33, and As shown in the circuit of FIG. 4, the drive to the motor 34 is stopped and held at the open position.

As described above, the metal piece is provided on the blade of the rotary rotor, and two electrodes and the pressure-sensitive conductive rubber are provided on the opening that is opened and closed by the blade to generate a signal current by pressing the metal piece of the rotor. (1) The position of the rotor is detected only by the conduction pressure of the pressure-sensitive conductive rubber in the opening and the convex part of the housing, and the variation of various parts is taken into account. Thus, the position of the rotor can be detected accurately and reliably, and the opening can be reliably opened and closed.

(2) The conduction of the pressure-sensitive conductive rubber can be changed depending on the contact state of the contacting metal pieces. For example, when the opening and the rotor blade contact, the gear is not damaged by the driving force of the motor. Adjustment can be made arbitrarily so as to secure a closing force for preventing infiltration of cool air.

(3) Since the detection device is composed of two electrodes, a pressure-sensitive conductive rubber, and a metal piece, the number of parts is small and assembly is easy. Since the signal current may be the base current of the transistor, switching can be performed reliably without contact contact or poor contact.

Advantageous Effects of Invention The present invention is provided at a cold air inflow duct opening, has an outlet portion communicating with the cold air inlet portion, and has a housing provided with an opening portion between the inlet portion and the outlet portion, and is rotatably provided in the housing. (1) The position of the rotor, which includes a rotor having blades for opening and closing the opening and a drive source for driving the rotor, and a detecting means (pressure-sensitive conductive rubber) for detecting opening and closing of the rotor is provided in the opening of the housing. The detection is determined only by the contact and pressurization of the pressure-sensitive conductive rubber provided on the housing opening and the metal piece provided on the rotor blade, that is, when the opening is closed by the rotor blade, the control circuit is controlled. Since the signal flows through the opening, it is possible to detect that the opening is closed reliably and accurately, and it is not affected by the variation in parts.

(2) Since the detecting means includes only two electrodes, pressure-sensitive conductive rubber, and a metal piece, it can be easily assembled and manufactured at low cost. Further, since the signal may be a minute current flowing through the base of the transistor, the switching can be performed without any contact soon.

 As described above, the present invention is very useful in practical use.

[Brief description of the drawings]

1 is an exploded perspective view of an embodiment of the damper thermometer according to the present invention, FIG. 2 is an enlarged view of a main part of FIG. 1, FIG. 3 is a sectional view of a main part of the damper thermometer of FIG. FIG. 1 is a control circuit diagram of the damper thermometer of FIG. 1, FIG. 5 is a side view of the conventional damper thermometer, and FIG. 6 is a detailed view of a gearbox portion of the damper thermometer of FIG. 20 ... Housing, 23 ... Cool air inlet, 24a, 24b ... Outlet, 25a, 25b ... Opening, 28 ... Electrode, 29 ... Pressurized conductive rubber, 34 ... Drive source, 38 ... Rotor, 38b, 38c, 38D…
... the wings.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References Japanese Utility Model Sho-59-18264 (JP, U) Japanese Utility Model Sho 62-115573 (JP, U) Japanese Utility Model Sho 62-194254 (JP, U) (58) Field (Int.Cl. ⁶ , DB name) F25D 17/08

Claims (1)

(57) [Claims] 1. A housing provided at a cool air inflow duct opening and having an outlet communicating with the cool air inlet, wherein an opening is provided between the inlet and the outlet, and a housing is rotatable in the housing. A rotor having a blade portion that opens and closes the opening, and a drive source that drives the rotor, two electrodes are provided in the housing opening, and a pressure conductive rubber is attached thereon, A damper thermostat, wherein a metal piece is provided at a position of the rotor in contact with the pressurized conductive rubber.