CN107388700B

CN107388700B - Refrigerator frost sensor

Info

Publication number: CN107388700B
Application number: CN201710041213.2A
Authority: CN
Inventors: 李晓
Original assignee: Chipsea Technologies Shenzhen Co Ltd
Current assignee: Chipsea Technologies Shenzhen Co Ltd
Priority date: 2017-01-20
Filing date: 2017-01-20
Publication date: 2020-08-21
Anticipated expiration: 2037-01-20
Also published as: CN107388700A

Abstract

The invention discloses a refrigerator frost sensor, which comprises a detection sensor and a reference sensor, wherein the detection sensor and the reference sensor are jointly arranged on an evaporation tube of a refrigerator evaporator, and the detection sensor comprises: the device comprises a base and at least two conductive pole pieces A; the reference sensor includes: the device comprises a base and at least two conductive pole pieces B; and a capacitive filler. The sensor provided by the invention fully utilizes the original structure of the refrigerator evaporator, can effectively reduce the complexity and volume of a frost detection structure, reduce the cost and improve the detection accuracy, thereby improving the defrosting effect of the refrigerator, improving the refrigeration efficiency and saving the electric energy.

Description

Refrigerator frost sensor

Technical Field

The invention belongs to the technical field of sensors, and particularly relates to a sensor for detecting frost condensation of a refrigerator.

Background

In the application of the refrigerator, the surface temperature of an evaporator used for refrigerating and heat exchanging is below zero; when moisture is present in the air, frost is easily formed and attached to the evaporator. After frost forms on the evaporator, the refrigeration efficiency can be seriously influenced, the refrigeration effect of the refrigerator is poor, and meanwhile, the power consumption is increased.

In the prior art, the refrigerator heats and defrosts the evaporator at regular time through the heating device, which obviously increases the power consumption of the refrigerator and has poor effect; for example, the timer may not initiate heater defrost when defrost is required; and the heating is started instead when defrosting is not needed, so that the waste of electric energy is caused.

In order to save electric power and improve defrosting effect, it is necessary to activate the heater for defrosting when frost is detected and it is confirmed that frost is indeed present.

In the patent application 201611046700.X, a capacitive frost detection device for a refrigerator and a method thereof are disclosed, which detect frost of the refrigerator through a sensor, and although the sensor for frost is mentioned, the specific structure of the sensor is not described in detail. In practice, in order to accurately detect the frost of the refrigerator, an on-site detection function must be realized, that is, the environment where the sensor is located must be consistent with the environment where the target component to be detected is located as much as possible, so that the frost condition of the target detection component can be accurately predicted through the sensor; in addition, the whole refrigerator production chain also needs to be considered, and the newly added sensor needs to change the existing production chain as little as possible, so that the effect of saving the overall cost is achieved.

Disclosure of Invention

Based on the above, the primary object of the present invention is to provide a frost sensor for a refrigerator, which can improve the accuracy of frost detection and reduce the cost, thereby improving the defrosting effect of the refrigerator, improving the refrigeration efficiency and saving the electric energy.

Another object of the present invention is to provide a frost sensor for a refrigerator, which makes full use of the original structure of an evaporator of the refrigerator and can effectively reduce the complexity and volume of a frost detection structure.

In order to achieve the purpose, the technical scheme of the invention is as follows:

the refrigerator frost sensor comprises a detection sensor and a reference sensor, wherein the detection sensor and the reference sensor are arranged on an evaporation tube of a refrigerator evaporator together, and the detection sensor and the reference sensor are arranged on the evaporation tube of the refrigerator evaporator together, wherein

The detection sensor comprises:

a base: the bracket is a bracket of the whole sensor and is divided into a positive base and a negative base; a groove is arranged on the pole piece for fixing the pole piece; the positive base and the negative base are coated and fixed on an evaporation tube of the refrigerator evaporator;

at least two conductive pole pieces A: positive and negative plates for forming a detection capacitor; the conductive pole piece A is fixed on the positive base and/or the negative base through the groove; the conductive pole piece A is in thermal contact with the evaporating tube through a heat-conducting insulating medium;

the reference sensor includes:

a base: the bracket is used for fixing the conductive pole piece B; and can be physically fixed on the evaporating pipe of the refrigerator evaporator;

at least two conductive pole pieces B: positive and negative plates for forming a reference capacitor; the two conductive pole pieces B are fixed on the positive base and/or the negative base through the grooves; the two conductive pole pieces B are in thermal contact with the evaporating tube through a heat-conducting insulating medium;

a capacitor filling member: the reference capacitor is used for filling the space between the two conductive pole pieces B of the reference capacitor.

The positive base and the negative base of the detection sensor are both provided with grooves to be coated and fixed on an evaporation tube of the refrigerator evaporator from two directions.

The conductive pole piece A is fixed on a positive base and/or a negative base of the detection sensor through a groove; the conductive pole piece B is fixed on the positive base and/or the negative base of the reference sensor through the groove, and meanwhile, the groove design enables the pole piece not to be in direct contact with the evaporation tube, and a proper gap is reserved, so that an electrical short circuit is avoided.

Furthermore, the detection sensor and the reference sensor share one base, and the detection sensor and the reference sensor can be physically fixed on an evaporation tube of the refrigerator evaporator; the conductive pole piece A and the conductive pole piece B are installed in a staggered mode to form a detection capacitor and a reference capacitor respectively;

the base is made of engineering plastics including but not limited to PF, POM and PVC materials.

Further, the capacitor filling piece and the base are made of the same material and are integrally formed.

Further, the conductive pole piece A and the conductive pole piece B adopt aluminum alloy sheets.

The heat-conducting insulating medium is heat-conducting silica gel.

Furthermore, the upper and lower surfaces of the conducting pole piece A and the conducting pole piece B are arranged in parallel with the axial direction of the evaporating tube, and the conducting pole piece A and the conducting pole piece B are arranged along the radial direction of the evaporating tube.

Or the upper and lower surfaces of the conducting pole piece A and the conducting pole piece B are perpendicular to the axial direction of the evaporating tube, and the conducting pole piece A and the conducting pole piece B are arranged along the axial direction of the evaporating tube.

The sensor provided by the invention fully utilizes the original structure of the refrigerator evaporator, can effectively reduce the complexity and volume of a frost detection structure, reduce the cost and improve the detection accuracy, thereby improving the defrosting effect of the refrigerator, improving the refrigeration efficiency and saving the electric energy.

Drawings

FIG. 1 is a schematic view of an evaporator tube of a refrigerator implemented in the prior art.

Fig. 2 is a front sectional view of a detection sensor implemented in the present invention.

Fig. 3 is a side cross-sectional view of a detection sensor embodying the present invention.

Fig. 4 is a front cross-sectional view of a reference sensor embodying the present invention.

Fig. 5 is a side cross-sectional view of a reference sensor embodying the present invention.

FIG. 6 is a schematic diagram of a first embodiment of a sensor according to the present invention applied to an evaporator tube of a refrigerator.

FIG. 7 is a schematic structural view of a second embodiment of the sensor of the present invention applied to an evaporator tube of a refrigerator.

Fig. 8 is a front cross-sectional view of a second embodiment of a sensor embodying the present invention.

Fig. 9 is a front cross-sectional view of a third embodiment of a sensor embodying the present invention.

Fig. 10 is a side cross-sectional view of a third embodiment of a sensor in accordance with the present invention.

FIG. 11 is a schematic structural view of a third embodiment of the sensor of the present invention applied to an evaporator tube of a refrigerator.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1, a currently common finned evaporator 100 for a refrigerator is shown, in which a frame 102 is used for fixing; the evaporation tube 101 is used for flowing condensate and gasifying the condensate so as to absorb heat and achieve the aim of refrigeration; the fins 103 are used to increase the heat exchange area, and therefore the fins 103 must be in good thermal contact with the evaporation tubes 101. The evaporating pipe is generally made of a copper pipe, the outer diameter of the evaporating pipe is cylindrical, and the common size of the evaporating pipe is generally 6-9 mm; the fins are made of aluminum alloy sheets, so that heat dissipation is facilitated. Usually, the evaporator frost starts from the evaporating pipe (low temperature) and mainly adheres to the fin, so when the frost is detected, the hot/wet environment of the fin needs to be fully simulated, the purpose of on-site detection can be achieved, and the detection accuracy is improved. In addition, for the existing evaporator, the production line is very mature, so the manufacturing cost is low; when frost is detected, the existing evaporator and the production line thereof should be improved as little as possible, so that the low cost can be realized.

Referring to fig. 2 and 3, a detection sensor 210 of an embodiment of the frost detecting sensor 200 is shown, wherein the detection sensor 210 includes a positive base 2105 and a negative base 2106, and is made of POM; the inner diameter of the positive and negative bases is just attached to the outer diameter of the copper pipe 101, so that the positive and negative bases can be tightly fixed on the evaporating pipe 101; the outer surface of the base is provided with a groove (such as a groove 2109) and can be extended with a prismatic table for fixing the conductive pole piece. The conductive pole pieces 2101-2104 adopt aluminum alloy sheets and are respectively inserted into the base through grooves; the groove design ensures that the conductive pole piece can not directly contact the evaporating tube 101, but a small gap of about 0.2-1 mm is reserved, and the electrical short circuit is avoided; the gaps between the pole pieces 2101-2104 and the evaporation tubes are in thermal contact by coating heat-conducting silica gel (as shown in 2108), thereby achieving the function similar to the fin 101 on the traditional evaporator 100.

For the sake of clarity of the drawing, only the grooves 2109 and the layer of heat-conducting silicone 2108 are illustrated, in practice there will be a corresponding groove and layer of heat-conducting silicone for each pole-piece pair.

Conductive pole pieces

2101 and 2102 form a detection plate capacitor C1, and conductive pole piece 2103 and conductive pole piece 2104 form a detection plate capacitor C2; during detection, C1 and C2 are in parallel connection, so that the conductive pole piece 2101 and the conductive pole piece 2103 are electrically shorted through a conducting wire to form an electrical node G1; conductive pole piece 2102 and conductive pole piece 2104 are electrically shorted by a wire to form electrical node P1. The nodes G1 and P1 are connected to a signal processing device, so that the capacity value change of the capacitor C1// C2 before and after frost condensation is identified.

The connection of the wires to the conductive pole pieces may be secured with screws, such as 2107.

Referring to fig. 4 and 5, a reference sensor 220 of an embodiment of the frost detecting sensor 200 includes a positive base 2205 and a negative base 2206, which are made of POM; the inner diameter of the positive base and the negative base is just matched with the outer diameter of the copper pipe 101, so that the positive base and the negative base can be tightly fixed on the evaporating pipe 101; the outer surface of the base is provided with a groove (shown as 2209) for fixing the pole piece. The pole pieces 2201-2204 are made of aluminum alloy sheets and are inserted into the base through grooves respectively; the grooves are designed so that the pole pieces can not directly contact the evaporating tube 101, but small gaps of about 0.2-1 mm are reserved, and electrical short circuit is avoided; the gaps between the pole pieces 2201-2204 and the evaporating tubes are in thermal contact by coating heat-conducting silica gel (as 2208), so that the function similar to that of the fins 101 on the traditional evaporator 100 is realized.

Pole pieces

2201 and 2202 form a reference plate capacitor C3, and pole piece 2203 and pole piece 2204 form a reference plate capacitor C4;

capacitance filling pieces

2210 and 2211 are respectively arranged between the plate capacitors C3 and C4; the capacitor filling member may be made separately or integrated with the base, and in fig. 3, the capacitor filling member 2210 is a part of the base 2205, and the capacitor filling member 2211 is a part of the base 2206. The existence of the capacitor filling piece enables no frost condensation space to be reserved between the plates of the capacitors C3 and C4, so that the capacitance value is not influenced by frost condensation or frost condensation. During detection, the C3 and the C4 are in parallel connection, so that the pole piece 2201 and the pole piece 2203 are electrically shorted through a conducting wire to form an electrical node G2; pole piece 2202 and pole piece 2204 are electrically shorted by a conductive line, forming electrical node P2. The nodes G2 and P2 are connected to a signal processing device, so that the capacity value change of the capacitor C3// C4 before and after frost condensation is identified.

The connection of the lead wires to the pole pieces may be secured with screws, such as shown at 2207.

The reference sensor 210 and the reference sensor 220 together constitute the frost detection sensor 200. In use, the signal conversion device determines the state of frost condensation of the refrigerator evaporator based on the ratio of the capacitance value of the sensing plate capacitor (C1+ C2) to the capacitance value of the reference plate capacitor (C3+ C4).

The base of the frost detecting sensor is made of POM material, and can also be made of other suitable engineering plastics, such as PVC \ PF (bakelite) \ PP, etc. The outer part of the evaporating pipe of the evaporator is round, and can be other shapes, such as square; correspondingly, the cross section of the inner cavity after the base is closed can be circular or square, but not limited to. The pole piece is made of aluminum alloy sheets, and other metal/alloy sheets with good electric conduction and heat conduction properties, such as stainless steel sheets, copper sheets and the like, can also be adopted; or other materials having both thermally and electrically conductive properties. The pole piece adopts rectangular upper and lower surfaces, and can also adopt other polygonal surfaces, such as three-shaped, arc-shaped, circular and the like. In addition, the mounting direction of the pole pieces is kept to be parallel to the axial direction of the evaporation tube, and the pole pieces are arranged in parallel along the radial direction of the evaporation tube; the arrangement is not limited to this, for example, the upper and lower surfaces of the pole piece may be perpendicular to the axial direction of the evaporating tube, or any other angle; the pole pieces can be arranged in parallel along the axial direction of the evaporation tube; or arranged in a fan shape along a radial direction in concentric circles as long as a plate capacitor can be constructed. In order to be compatible with the structure of the original evaporator better, the base can be hollowed out under the condition of ensuring the structural strength, so that the evaporating pipe has more contact areas with the outside air, and the heat dissipation characteristic of the original evaporating pipe is ensured. The capacitor filler is generally made of the same material as the base.

Referring to fig. 6, a schematic view of the frost detecting sensor 200 mounted on the evaporator 100 is shown. The detection sensor 210 and the reference sensor 220 are respectively arranged on an upper evaporation pipe and a lower evaporation pipe (actually, one evaporation pipe is communicated with the upper evaporation pipe and the lower evaporation pipe); the original evaporator only needs to cancel part of fins and install the sensor without any change; the sensor 200 can be fixed on the evaporating pipe 101 by screws or glue, and belongs to an external hanging type, so that the original evaporator production line is hardly changed. Referring to fig. 7, the detection sensor 210 and the reference sensor 220 are horizontally installed on the same evaporation pipe.

Referring to fig. 8, the frost detection sensor 400 realizes a detection sensor and a reference sensor on one base (a positive base 4004 and a negative base 4007). The pole piece 4001, the pole piece 4003 and the capacitance filler 4002 form a reference plate capacitor C5 of the reference sensor; the pole piece 4003, the pole piece 4006 and the capacitance filler 4005 form a reference plate capacitor C6 of the reference sensor; the pole piece 4001 and the pole piece 4008 form a detection panel capacitor C7 of the detection sensor; the pole piece 4008 and the pole piece 4006 constitute a reference plate capacitor C8 of the reference sensor. The

pole pieces

4001, 4003, 4006 and 4008 are all L-shaped folded pole pieces, so that two different capacitors can be formed. For example, one side of the pole piece 4001 may be joined to a side of the pole piece 4003 that is relatively parallel to form the base plate capacitor C5; meanwhile, the other side of the pole piece 4001 and the side of the pole piece 4008 which is relatively parallel form a detection plate capacitor C7. The folded angle of the pole piece can have a larger thermal contact area with the evaporating tube 101, thereby being beneficial to realizing the heat dissipation function of the original evaporator fin. The gaps between the evaporating tubes 101 and the corners of the pole pieces are connected by a heat-conducting silica gel layer (such as 4009).

Referring to fig. 9 and 10, a frost detection sensor embodiment 500 is shown, including a positive base 5006 and a negative base 5008; the pole piece 5001-5004; the pole pieces are arranged in a direction perpendicular to the surface of the evaporating tube 101, and the pole pieces are arranged in parallel along the axial direction of the evaporating tube 101. The pole piece 5001 and the pole piece 5002 which are arranged in parallel relatively and the capacitance filler 5005 form a reference plate capacitor C8; the pole piece 5003 and the pole piece 5004 which are arranged in parallel relatively form a detection panel capacitor C9; the distance between the pole pieces 5001-5002 is about 5 mm; the pole piece 5004 and the pole piece 5002 may be electrically shorted as the same pole piece in electrical characteristics, or may be combined into one pole piece. The pole piece is secured to the base by a groove and is in thermal contact with the evaporator tube 101 through a layer of thermally conductive silicone 5007. The capacitor filler 5005 and the base are integrated, and is greater than or equal to the overlapping area of the pole piece 5002 and the pole piece 5001.

Fig. 11 is a schematic view showing the frost detecting sensor 500 mounted on the evaporator 100. The sensor 500 is mounted in the lower left corner region of the evaporator tube 101 of the evaporator 100 with the pole piece oriented parallel to the fins.

In a word, the frost detection sensors avoid greatly changing the original evaporator through the externally-hung installation, the production line of the original evaporator is not influenced, and meanwhile, the pole pieces of the sensors can realize the function of the original evaporator fins (or equivalent parts), so that the frost detection sensors can be used as one part of the evaporator to realize the function of the traditional evaporator and have the function of frost detection.

Therefore, the sensor realized by the invention fully utilizes the original structure of the refrigerator evaporator, can effectively reduce the complexity and the volume of a frost detection structure, reduce the cost and improve the detection accuracy, thereby improving the defrosting effect of the refrigerator, improving the refrigeration efficiency and saving the electric energy.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims

1. The refrigerator frost sensor is characterized by comprising a detection sensor and a reference sensor, wherein the detection sensor and the reference sensor are jointly arranged on an evaporation tube of a refrigerator evaporator, and the detection sensor and the reference sensor are arranged on the evaporation tube of the refrigerator evaporator together, wherein

The detection sensor comprises:

a base: the bracket is a bracket of the whole sensor and is divided into a positive base and a negative base; a groove is arranged on the conductive pole piece A for fixing the conductive pole piece A; the positive base and the negative base are coated and fixed on an evaporation tube of the refrigerator evaporator;

the reference sensor includes:

at least two conductive pole pieces B: positive and negative plates for forming a reference capacitor; the two conductive pole pieces B are fixed on the positive base and/or the negative base through the grooves; the two conductive pole pieces B are in thermal contact with the evaporation tube through a heat-conducting insulating medium;

2. The frost sensor of claim 1 wherein said detection sensor and said reference sensor share a base, said base being physically secured to an evaporator tube of a refrigerator evaporator; and the conductive pole piece A and the conductive pole piece B are installed in a staggered mode to form a detection capacitor and a reference capacitor respectively.

3. The refrigerator frost sensor of claim 1, wherein said base is made of an engineering plastic including but not limited to PF, POM, PVC material.

4. The frost sensor of claim 3, wherein the capacitive filler and the base are formed of the same material and are integrally formed.

5. The refrigerator frost sensor of claim 1, wherein the pole piece is an aluminum alloy sheet.

6. The refrigerator frost sensor of claim 1, wherein said thermally conductive dielectric is thermally conductive silicone.

7. The frost sensor of claim 1, wherein the top and bottom surfaces of said conductive electrode pieces a and B are disposed parallel to the axial direction of the evaporator tube, and said conductive electrode pieces a and B are arranged along the radial direction of the evaporator tube.

8. The frost sensor of claim 1, wherein the top and bottom surfaces of said conductive electrode pieces a and B are disposed perpendicular to the axial direction of the evaporator tube, and said conductive electrode pieces a and B are arranged along the axial direction of the evaporator tube.