JPS609226B2 - Defrost control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for defrosting frost formed on an evaporator of a refrigeration device such as a refrigerator, or an extra-conductive coil of a heat pump, and particularly to an improvement of a device that generates a defrosting command. Pertains to.

By integrating the operation of compressors in refrigeration equipment such as subordinates and refrigerators,
There are devices in practical use that issue a defrosting command when the accumulated time reaches, for example, 8 hours, but in this case, the time is set so that defrosting is completed even under adverse conditions such as an outside temperature of 30°C. There is.

Therefore, even if the outside air temperature is, for example, 10°C, a defrost command will be issued if the cumulative operating time has elapsed for 8 hours, but at this time there will be substantially less frost and the outside air temperature will be maintained at around 10°C thereafter. In some cases, there may be no problem even if defrosting is performed after 8 hours. However, even though the amount of frost on the food is small, defrosting is performed for the same amount of time as when there is a large amount of frost, which causes a loss in power consumption and an increase in the temperature inside the refrigerator. The purpose of the present invention is to eliminate these drawbacks, and its purpose is to automatically control the defrost interval according to changes in outside temperature or humidity, and to perform efficient defrosting and reduce unnecessary power consumption. The purpose of the present invention is to provide a defrosting control device that is capable of avoiding the consumption of air and minimizing time loss due to switching.

The present invention provides a competitive point operating member that operates an electrical contact for defrosting control, a motor that drives the contact operating member, and a motor that is located between the contact operating member and the motor to control the movement of the contact operating member. , consisting of a speed change mechanism that can change at least from high speed to low speed or from low speed to high speed depending on the outside temperature or humidity, and the speed change mechanism is configured with a toggle motion mechanism driven by a thermal displacement member such as a bellows or diaphragm. In addition, the speed change mechanism is configured to maintain its speed regardless of changes in outside temperature or humidity that occur during the movement range of the contact actuating member. Even if the temperature or humidity changes during the contact switching operation, the speed change operation can be prevented from occurring, and malfunctions can be avoided when the traverse point is switched.

One embodiment will be described below based on the drawings. Figure 1~
In FIG. 3, a case 1 surrounds the main parts of the defrosting control device, and is composed of an upper case 2 and a lower case 3.

Electrical contacts, generally designated 4, are contacts 4a', 4b', 4
Consisting of three contact plates 4a, 4b, 4c having c',
It is inserted and supported within a locking groove 5 formed integrally with the lower case 3. The members indicated by 6 as a whole are contact operating members for switching the electrical contacts 4, and include a lower cam surface 7 that engages with the tips of the contact plates 4a and 4b, and an upper cam surface that engages with the tips of the contact plate 4c. The cam member 9 includes a cam member 9 which is integrally formed with a cam member 8 having the same shape and a stepped shape, and a cam drive member 10 which rotates the cam member 9 in one direction. A shaft 11 of the cam member 9 is rotatably supported in bearing holes 12 and 13 formed in the upper and lower cases 2 and 3, and a cam drive member 10 is rotatably supported with the shaft 11 below the cam member 9. ing. The cam driving member 10 and the cam member 9 are arranged so that the cam member 9 can be moved in only one direction by the engagement between the ratchet teeth 14 formed on the inner periphery of the lower end of the cam member 9 and the ratchet melon T5 formed on the outer periphery of the upper end of the cam driving member 10. The contact plates 4a, 4b, and 4c are prevented from being damaged by either rotating the cam member 9 or, conversely, by allowing the cam member 9 to rotate in only one direction by external force. Next, the operations of the lower cam surface 7, the upper cam surface 8, and the contact plates 4a, 4b, and 4c of the cam member 9 will be explained.

In the state shown in Figure 1, contacts 4a' and 4b' are closed, and contact 4b'
, 4c' are open. In this state, when the cam member 9 further rotates in the direction of the arrow EOM, while the contact plate 4c is on the peak 8' of the upper cam surface 8, the contact plate 4a moves from the peak 7' of the lower cam surface 7 to the upper cam surface. Contact plate 4 on top of peak 8' of 8
c, the contact 4 opens as shown in FIG. 6, and at the same time contacts 4a' and 4c' close. In this state, the rotation of the cam member 9 is temporarily stopped by the electrical connection described later, but when the rotation starts again, only the contact plate 4c falls from the peak 8' of the upper cam surface 8, as shown in FIG. Contact 4a' and contact 4c' open, and almost at the same time, contact 4b on Yamato 7' of lower cam surface 7 falls onto contact plate 4a, and contact 4
b' and contact 4a' are closed. This state is the same as the initial state as shown in FIG. Next, a mechanism generally designated by 16 is a speed change mechanism for switching the rotation of the contact actuating member 6 between high speed and low speed according to changes in temperature or humidity. 17
For example, the second shaft is a deceleration output shaft of a synchronous motor 8 that rotates once, and projects inward from the lower surface of the lower case 3, to which a gear A is fixed.

Reference numeral 19 denotes a transmission member, the upper end shaft 20 of which competes with the shaft 22 of the upper case 2, and the lower end shaft 21 of which competes with the shaft 22 of the lower case 3.
It is supported so that it can rotate freely.

The lower end 211 of the transmission member 19 rotatably supports a stage gear 24 in which a gear B with a small number of teeth is formed in the upper part and a gear C with a large number of teeth in the lower part are integrally formed in two stages. On the other hand, the shafts 25 and 26 provided in the transmission section 19 have step gears 24
A gear D, which is always in mesh with the gear B of the step gear 24, and a gear E, which is always in mesh with the gear C of the stepped gear 24, are each rotatably supported. The gears D and E are arranged so as to selectively mesh with the gear A of the deceleration output shaft 17 of the synchronous motor 8 as the transmission member 19 rotates. The rotation range of the speed change member 19 is formed in the lower case 3. This is determined by the stopper 27 and the notch 28 formed in the transmission member 19. Furthermore, cylindrical parts 29 and 30 without teeth at the upper and lower ends of gear A
are formed, and gears D and E are also formed with corresponding cylindrical portions 31 and 32 which are in green contact with the cylindrical portions 29 and 30, respectively.
This prevents gears A and D or gears A and E from meshing excessively, and also eases assembly and molding costs and facilitates work. The gear C is connected to a connecting gear F, and the connecting gear F is further connected to the lower segment gear G of the stepped gear 33 at all times. The upper gear of the one-stage gear 33 has two teeth in the embodiment, and meshes with the gear 1 formed on the cam drive member 101 of the contact operating member 6.
Rotate 0 intermittently. Another element of the transmission mechanism 16 is a toggle motion mechanism shown at 34, which consists of a toggle rod 36 rotatably supported by a pivot 35, a toggle push shear 37, and a toggle spring 38 that biases the push shear 37 in one direction. Become. The tip of the toggle pusher 37 is always brought into contact with a toggle slide 39 formed in the transmission village 19 by a toggle ring 38, and the center of the toggle slide 39 is aligned with the axes of the shafts 21 and 22. Reference numeral 40 denotes a toggle operating member supported on a pivot 41 so as to be freely rotatable, and a pair of fork-shaped arms 4
2 and 43 are formed, and a pressure receiving part 46 that receives a pin 45 of a bellows 44 and a leg part 48 that locks a load spring 47 are formed.

49 is an adjustment screw for adjusting the spring force of the load spring 47, and 50 is a fixed shaft of the spring 47.

The bellows 44 also has a slot 5 formed in the lower case 3.
1 is inserted and supported. Further, 52 is a capillary tube, 53 is a heat-sensitive cylinder, and 54 is a stopper for regulating the movement of the toggle operating member 40. A mechanism generally designated by 55 forcibly prevents the speed change mechanism 16 from changing speed according to the rotational position of the contact actuating member 6, and connects the gear D and the gear A or the gear E and the gear A at a certain time using a bellows 44. This is a shift holding mechanism that maintains the speed change regardless of its function. This speed change holding mechanism 5
Reference numeral 5 denotes a holding rod whose one end rests against a peak 56' of a holding cam surface 56 formed at the top of the cam member 9, and whose other end rests against a protrusion 57 formed integrally with the toggle actuating member 4. 58
Contains. 59 is a guide rail that supports the holding rod 58 in a slidable manner.

In the state shown in FIG. 1, one end of the holding rod 58 is at the peak 56', and at this time the temperature or humidity decreases and the bellows 4
4 is compressed, the force of the load spring 47 prevents the toggle actuating member 40 from rotating in the direction of the arrow Q, thereby eliminating movement of the toggle rod 36 and maintaining the engagement between the gears D and A. . In the embodiment, this holding corresponds to the switching of the contact plates 4a, 4b, 4c, and the gear F is rotated at high speed at this time. 4 and 5 are electrical wiring diagrams and refrigeration circuit diagrams of the refrigeration system, in which 101 is a thermostat for detecting the internal temperature of a refrigerator (not shown), 102 is an electric motor of a compressor 102', 103 is defrost heater, 104
105 is a temperature fuse, and 105 is a defrosting completion detection thermostat that turns off at a predetermined temperature.

106 is an evaporator, 107 is a fan motor that circulates cooled air, 108 is a capillary tube, 109 is a condenser, and 110G is an accumulator.

As is clear from FIG. 4, when the thermostat 101 is closed and the compressor motor 102 is operated, the heater 10
3 and thermal fuse 104 to operate the synchronous motor 18 at the same time, however, the impedance of the synchronous motor 18 does not allow enough current to flow to substantially heat the heater 103. When the synchronous motor 18 integrates the operation of the compressor motor 102 for a predetermined period of time, the contact plate 4a and the contact plate 4b are connected, and the operation of the compressor motor 102 is stopped. At the same time, the contact plate 4a closes the contact plate 4c. Then, the defrost heater 03 is energized via the defrost completion detection thermostat 105, but at this time, the synchronous motor 1
8 is short-circuited via the defrosting completion detection thermostat 105 by the contact plates 4a and 4c, and since no alternating voltage is applied, no current flows and the operation is stopped. Then, when the frost in the evaporator 106 melts and the ambient temperature rises, the defrosting completion detection thermostat 105 detects this temperature and opens the circuit, cutting off the power to the defrosting heater 103. Then, the synchronous motor 8 starts operating again, and the contact plate 4a and the contact plate 4c
The circuit is opened, the contact plate 4a and the contact plate 4b are closed, and the cooling operation is restarted, and the synchronous motor 18 continues to operate.
Next, the operation of the transmission mechanism 16 in the above-mentioned horizontal transmission will be explained.

In the state shown in Figure 7, gear A and gear D are meshing, and gear A
, Gear D, Gear B, Gear C, Gear F, Gear G, Gear Day,
A gear train called gear L drives the cam section 9 at high speed. When the temperature or humidity decreases, the heat-sensitive cylinder 53 senses this and the bellows 44 contracts. Then, the force of the load spring 47 moves the toggle actuating section 40 in the direction of arrow Q. This movement is performed by the toggle spring 3 at the arm 43.
8, the toggle rod 36 is rotated in the direction of arrow S. And the toggle pusher 37 is the toggle slide 39
Gear A and gear D are kept in mesh until they pass the center point (dead point), and the toggle actuating member 40 rotates in the direction of arrow Q, and the toggle rod 36 passes the dead point and rotates in the direction of arrow S. Then, toggle rod 36
is rapidly rotated in the direction of the arrow S by the force of the toggle spring 35 to rotate the transmission member 19 in the direction of the arrow 'r', and the eighth
As shown in the figure, release the mesh between gear A and gear D,
Gear A and gear E are engaged. That is, gear A,
The cam member 9 is rotated at a low speed by a gear train of gear E, gear C, gear F, gear G, gear E, and gear 1. Further, when the temperature or humidity increases and the bellows 44 expands, the toggle actuating member 40 is rotated in the direction of arrow P against the force of the load spring 47.

Then, the arm 42 rotates the toggle rod 36 in the direction of arrow R, the toggle pusher 37 slides on the toggle slide 39, and when the dead point is passed, the transmission member 1 is rapidly rotated.
The cam member 9 is rotated in the direction of the arrow U to release the mesh between the gear A and the gear E, and the mesh between the gear A and the gear D is brought back to the state shown in FIG. 7, and the cam member 9 is rotated at high speed again. make it move. Therefore, depending on changes in temperature or humidity, the cam member 9 is automatically rotated at a high speed when the temperature is high or at a low speed when the temperature is low or high. When the temperature is high, the interval between defrost commands can be shortened and the interval between defrost commands can be tightened, and when the temperature is low or the temperature is low, the interval between defrost commands can be shortened and extended. Therefore, the defrost timing can be controlled according to changes in the amount of frost formed on the evaporator 106. , efficient defrosting is possible.Furthermore, since a toggle motion mechanism 34 is provided for switching from high speed to low speed or from low speed to high speed, the cutting time is short and the accumulation of cutting loss time does not have an adverse effect.

Furthermore, the use of thermal displacement members such as bellows or diaphragms eliminates the need for electrical connections and easily provides the necessary switching force. In addition, since the speed change holding mechanism 55 forcibly maintains the operation of the speed change mechanism 16 when the electrical contacts 4 are switched, the speed change operation is prevented from occurring due to changes in temperature or humidity during the switching operation of the contacts. Prevents malfunctions when the contacts are activated. When using this device to defrost a heat source coil placed outdoors in a heat pump, the lower the outside temperature or humidity, the greater the amount of frost formation, so when the outside temperature is high, rotate the cam member at a low speed to By rotating the cam member at high speed when the temperature is low, the defrosting efficiency of the heat pump can be improved.

As described above, the present invention includes a point operating section for operating an electrical contact for defrosting control in a device that issues a defrosting command, a motor for driving the contact operating member, and a motor for driving the contact operating member and the motor. and a speed change mechanism that can change the movement of the contact actuating member from at least high speed to low speed or from low speed to high speed according to the outside temperature or humidity, so that the defrosting interval can be changed according to changes in the outside temperature or humidity. It can be controlled automatically, allowing efficient defrosting and reducing power consumption.

Furthermore, since the transmission mechanism is constructed with a toggle motion mechanism driven by a thermal displacement member such as a bellows or diaphragm, there is little time loss during switching, and even if there are many fluctuations in temperature or humidity around the switching set temperature or humidity. , the accumulation of loss time is small, no electrical connection is required for switching, and the force necessary for switching can be easily obtained. Furthermore, by temporarily holding the speed change mechanism at a high speed or low speed side at a specific point within the movement range of the contact actuator, regardless of the outside temperature or humidity, the temperature or humidity can be adjusted to This has the effect of preventing a shift operation from occurring even if the shift occurs, and avoiding malfunctions when cutting the bush point.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a defrosting control device showing an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line n--lo in FIG. 1, and FIG. 3 is a cross-sectional view taken along line m-m in FIG. 4 and 5 are electrical wiring diagrams and refrigerant circuit diagrams showing an example of application to a refrigeration system, FIG. FIG. 8 is a plan view and a partial plan view showing the gear shift operating state with respect to FIG. 1. 4...-Electrical contacts, 4a, 4b, 4c...
・・Contact plate ``6...Contact operating member, 9...
・Cam member, 10...Cam drive member, 16...
...Transmission mechanism, 18...Synchronous motor, 19
...... Speed change member, 34... Toggle motion mechanism, 37... Toggle pusher, 39... Toggle slide, 40... Toggle operating member, 44
...Bellows, 53 ...Thermosensitive tube, 56
・・・・・・Shift holding mechanism. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] 1. A device that issues a defrosting command, comprising: a contact operating member that operates an electrical contact for defrosting control; a motor that drives the contact operating member; and a combination of the contact operating member and the motor. In between, there is provided a speed change mechanism capable of converting the movement of the contact actuating member from at least high speed to low speed or from low speed to high speed according to outside temperature or humidity, and the speed change mechanism is driven by a thermal displacement member such as a bellows or a diaphragm. A defrosting control device characterized by being configured with a toggle motion mechanism. 2. The defrosting control device according to claim 1, wherein the speed change mechanism maintains its speed regardless of changes in outside temperature or humidity that occur during the movement range of the contact operating member.