EP2738498A2

EP2738498A2 - Refrigerator

Info

Publication number: EP2738498A2
Application number: EP13194636.0A
Authority: EP
Inventors: Wentao Diao; Benhe Dou; Jianfeng Zhang
Original assignee: BSH Bosch und Siemens Hausgeraete GmbH
Current assignee: BSH Hausgeraete GmbH
Priority date: 2012-12-01
Filing date: 2013-11-27
Publication date: 2014-06-04
Also published as: CN203286843U; EP2738498A3

Abstract

Disclosed is a refrigerator. The refrigerator includes a storage space (2) capable of keeping a low-pressure state; a vacuum pump (3), including a pump body (31) for defining a pump cavity (30), an air inlet (321, 322) communicating with the pump cavity (30), an air outlet (331, 332) communicating with the pump cavity (30), a piston (36) accommodated in the pump cavity (30), and a driving device for driving the piston (36) to move in the pump cavity (30); and an air exhaust path (4), connected to the storage space (2) and the air inlet (321, 322). As suggested, the driving device includes a coil (381, 382), wherein the coil is capable of generating an electromagnetic force for driving the piston to move in the pump cavity, so as to suck air in the storage space into the pump cavity via the air inlet and discharge air out of the pump cavity via the air outlet.

Description

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a refrigerator, and more particularly to a refrigerator having a storage space capable of keeping a low-pressure state.

Related Art

A refrigerator capable of preserving articles in a low-pressure environment is known in the prior art. Such a refrigerator generally has a storage chamber capable of being evacuated (also referred to as "vacuum chamber" in the industry). By exhausting at least part of air in the storage chamber, air content in the storage chamber is reduced so as to weaken oxidation of food, thereby prolonging preservation time and quality of the food.
Chinese Invention Patent CN 101331970 B discloses a vacuum preservation system and a control method thereof, including a low-pressure chamber/vacuum chamber, a vacuum pump and an air exhaust path connected between the vacuum pump and the low-pressure chamber, wherein when the vacuum pump operates, air in the low-pressure chamber can be exhausted through the air exhaust path.
In the prior art, a vacuum pump for a refrigerator includes a motor, a cylinder, a crank rod mechanism driven by the motor, and a piston accommodated in the cylinder and driven by the crank rod mechanism to reciprocate in the cylinder. Such a vacuum pump has a relatively large volume and a high cost.
Therefore, it is necessary to develop a small and relatively inexpensive vacuum pump applied to a refrigerator.

SUMMARY OF THE INVENTION

One objective of the present invention is to solve at least one of the above technical problems, thereby providing a refrigerator having a more reliable low-pressure storage system.
Therefore, one aspect of the present invention provides a refrigerator. The refrigerator includes: a storage space capable of keeping a low-pressure state; a vacuum pump, including a pump body for defining a pump cavity, an air inlet communicating with the pump cavity, an air outlet communicating with the pump cavity, a piston accommodated in the pump cavity, and a driving device for driving the piston to move in the pump cavity; and an air exhaust path, connected to the storage space and the air inlet; the refrigerator is characterized in that, the driving device includes a coil, wherein the coil is capable of generating an electromagnetic force for driving the piston to move in the pump cavity, so as to suck air in the storage space into the pump cavity via the air inlet and discharge air out of the pump cavity via the air outlet.
The piston is directly driven to move in the pump cavity through an electromagnetic force, and therefore it is unnecessary to use a motor or a transmission mechanism to drive the piston, which helps to greatly reduce the volume and parts of the vacuum pump, so that it can be expected to obtain a small and relatively inexpensive vacuum pump.
Other individual features or those combined with other features to be regarded as characteristics of the present invention are set forth in the following appended claims.
According to a preferred embodiment of the present invention, the coil is fixed to the pump body.
According to a preferred embodiment of the present invention, the coil is disposed around the pump cavity.
According to a preferred embodiment of the present invention, the coil is fixed to an end portion of the pump body.
According to a preferred embodiment of the present invention, the refrigerator includes two groups of coils each fixed to a corresponding end of the pump body.
According to a preferred embodiment of the present invention, the two groups of coils supply power simultaneously or alternately.
According to a preferred embodiment of the present invention, the pump body includes a cylinder barrel and an end cover connected to an end portion of the cylinder barrel, and the air inlet and/or the air outlet is located on the end cover
According to a preferred embodiment of the present invention, the pump body includes a first end and a second end opposite each other, the piston is located between the first end and the second end, and the first end and the second end are each disposed with at least one air inlet and at least one air outlet.
According to a preferred embodiment of the present invention, the air exhaust path includes a multi-way pipe connected to each of the air inlets, and the multi-way pipe includes a plurality of branches connected in parallel and each connected to each of the air inlets.
According to a preferred embodiment of the present invention, the pump body includes a first end and a second end opposite each other, the piston is located between the first end and the second end, the first end is disposed with at least one air inlet and at least one air outlet, and the second end is kept in communication with air.
According to a preferred embodiment of the present invention, the piston includes a magnet.
According to a preferred embodiment of the present invention, the refrigerator includes a shock attenuation device for buffering a motion of the piston.
According to a preferred embodiment of the present invention, the shock attenuation device includes a magnet and/or a spring connected to the piston.
According to a preferred embodiment of the present invention, the refrigerator includes a reset magnet arranged along a middle portion of the pump cavity.
The structure and other invention objectives as well as beneficial effects of the present invention will be more comprehensible with reference to the accompanying drawings and the description about the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

As a part of the specification and for facilitating further comprehension of the present invention, the following accompanying drawings illustrate specific implementation manners of the present invention, and describe the principle of the present invention together with the specification.

FIG. 1 is a schematic view of a refrigerator according to one preferred embodiment of the present invention;
FIG. 2 is a schematic view of a refrigerator according to another preferred embodiment of the present invention;
FIG. 3 is a schematic view of a vacuum pump according to yet another preferred embodiment of the present invention;
FIG. 4 is a schematic view of a vacuum pump according to yet another preferred embodiment of the present invention;
FIG. 5 is a schematic view of a vacuum pump according to yet another preferred embodiment of the present invention; and
FIG. 6 is a schematic view of a vacuum pump according to yet another preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Referring to FIG. 1, a refrigerator 1 has a heat-insulating inner space 10. The inner space 10 may be defined by a cabinet (not shown) having heat-insulating materials, and is closed or opened through a door (not shown) connected to the cabinet.
The refrigerator 1 has a storage space 2 capable of keeping a low-pressure state. The storage space 2 may be formed by a storage unit 11 mounted in the inner space 10, and also may be directly defined by the inner space 10.
The refrigerator 1 has an air exhaust system 12 for at least partially exhausting air in the storage space 2. The air exhaust system 12 includes a vacuum pump 3 and an air exhaust path 4 connected between the storage space 2 and the vacuum pump 3. The air exhaust path 4 may be defined by at least one pipe and at least one pipe joint.
The air exhaust system 12 may include a mechanical valve 8 located in the air exhaust path 4 and for stopping external air from entering the storage space 2. The mechanical valve 8 may be disposed on the storage unit 11. The mechanical valve 8 may have a deformable valve plate, and under the action of a difference between internal and external pressures, the valve plate is deformed and sealed in an air exhaust channel on the storage unit 11. The mechanical valve 8 may adopt the existing scheme, for example, the scheme disclosed in Patent Application No. CN200910028963.1 submitted by the applicant, which is therefore not described more herein.
The air exhaust system 12 includes a detection unit 9 for judging whether the storage space 2 has reached a preset pressure. The detection unit 9 may include a pressure sensor for detecting an air pressure.
In this embodiment, the detection unit 9 is connected to the air exhaust path 4, which judges a pressure in the storage space 2 by detecting a pressure of the air exhaust path 4. In an alternative embodiment, the detection unit 9 also may directly detect the pressure of the storage space 2.
The air exhaust system 12 further includes a branch 5 connected with the air exhaust path 4. One end of the branch 5 is in fluid communication with the air exhaust path 4, while the other end is connected with external air, i.e., connected with an atmospheric pressure. The effect of the branch 5 lies in that, after the vacuum pump 3 ends work, the branch 5 is opened so that air flows to the air exhaust path 4 through the branch 5, the pressure in the air exhaust path 4 is equivalent to the atmospheric pressure, and therefore a pressure differential is established on two sides of the mechanical valve 8, and the mechanical valve 8 may be closed, thereby preventing air from entering the storage space 2 from the air exhaust channel.
The branch 5 is provided with a solenoid valve 7 for controlling opening or closing of the branch 5. The solenoid valve 7 is connected with a controller 6 through work, and decides whether to open or close the branch according to a signal from the controller 6.
FIG. 2 is a schematic structural view of a vacuum pump according to one preferred embodiment of the present invention. As shown in FIG. 2, the vacuum pump 3 includes a pump body 31 defining a pump cavity 30, at least one air inlet 321, 322, at least one air outlet 331, 332, a piston 36 accommodated in the pump cavity 30, and a driving device for driving the piston 36 to reciprocate in the pump cavity 30.
The pump body 31 may include a cylinder barrel 311 and end covers 3121, 3122 connected to end portions of the cylinder barrel 311. In this embodiment, two ends of the cylinder barrel 311 are open and are respectively closed by the end covers 3121, 3122 connected to a corresponding end of the cylinder barrel 311, and when two end walls of the vacuum pump 3 are provided with air inlets or air outlets, such a construction is particularly advantageous.
The piston 36 is accommodated in the pump cavity 30 and is capable of reciprocating along the pump cavity 30. Relative to the piston 36, the pump cavity 30 is partitioned into a first cavity 301 located on one side of the piston 36 and a second cavity 302 located on the other side of the piston 36. A peripheral surface of the piston 36 and an inner wall surface of the pump cavity 30 are preferably sealed therebetween. In this embodiment, the piston 36 includes a magnet.
One end of the air inlets 321, 322 is connected with the air exhaust path 4, and the other end may be in fluid communication with the pump cavity 30. The vacuum pump 3 includes an air inlet check valve 323 capable of closing the corresponding air inlet 32.
The air exhaust path 4 may include a multi-way pipe (not shown) connected with each of the air inlets 321, 322, and the multi-way pipe includes a plurality of branches connected in parallel and each connected to each of the air inlets 321, 322.
In this embodiment, the vacuum pump 3 is provided with two air inlets 321, 322, each of the air inlets 321, 322 is located at a corresponding end portion of the pump body 31, and communicates with a corresponding one of the first cavity 301 and the second cavity 302. Preferably, each of the air inlets 321, 322 is located on the corresponding end covers 3121, 3122.
One end of each of the air outlets 321, 322 may be in fluid communication with a corresponding portion of the pump cavity 30, and the other end is in fluid communication with the outside. Air in the pump cavity 30 may be exhausted through the air outlets 331, 332. The vacuum pump 3 includes an air exhaust check valve 333 capable of respectively closing the air outlets 331, 332.
In this embodiment, the vacuum pump 3 is provided with two air outlets 331, 332, each of the air outlets 331, 332 is located at a corresponding end portion of the pump body 31, and communicates with a corresponding one of the first cavity 301 and the second cavity 302. Similar to the air inlets 321, 322, each of the air outlets 331, 332 is located on the corresponding end covers 3121, 3122.
The driving device includes coils 381, 382 for directly driving the piston 36 to move in the pump cavity 30 through an electromagnetic force. In this embodiment, the coils 381, 382 are respectively fixed to a first end 315 and a second end 316 of the pump body 31. Arrangement manners (directions) of the coils 381, 382 are exactly the same, and when the two coils 381, 382 are powered with an alternating current at the same time, distributions of magnetic lines of force of the coils 381, 382 located on two sides of the piston 36 are exactly the same. Supposing a magnetic field generated by the coil 381 at a certain moment has an attractive effect on the piston 36 including a magnet, and a magnetic field generated by the coil 382 has a repellent effect on the piston 36, under the simultaneous effects of the two magnetic fields, the piston 36 may move to the first end 315, at this time, the first cavity 301 adjacent to the first end 315 is an exhaust stroke, air in the first cavity 301 is exhausted out of the first cavity 301 through the opened air outlet 331, and the air inlet 321 communicating with the first cavity 301 is closed; the second cavity 302 adjacent to the second end 316 is a suction stroke, that is, the air inlet 322 communicating with the second cavity 302 is opened, air can be sucked into the second cavity 302 from the storage space 2 through the opened air inlet 322, and the air outlet 332 keeps closed; when the current is reversed, the magnetic field generated by the coil 381 has a repellent effect on the piston 36, and the magnetic field generated by the coil 382 has an attractive effect on the piston 36, and under the simultaneous effects of the two magnetic fields, the piston 36 moves towards the second end 316, at this time, the first cavity 301 is a suction stroke, and the second cavity 302 is an exhaust stroke.
The vacuum pump 3 may include a shock attenuation device fixed to each of the end covers 3121, 3122 and used for buffering the piston 36 to move. In this embodiment, the shock attenuation device includes magnets 391, 392 fixed onto each of the end covers 3121, 3122 and with poles opposite to those of the piston 36.
Due to the use of the alternating current, a change of the magnetic line of force is 50 Hz/s, therefore the stroke of the piston 36 may not be great. Meanwhile, the repellent effect of the shock attenuation magnets 391, 392 at two sides on the piston 36 may facilitate the piston 36 to be located at a central position of the pump cavity 30 when in the stationary status.
In the embodiment as shown in FIG. 3, a reset magnet 40 is added to a central position of the cylinder barrel 311. In an axial direction along the pump cavity 30, poles of the reset magnet 40 are opposite to those of the piston 36, which may avoid a situation where the piston 36 cannot be restored to the central position when in the stationary status. The rest work principles of the embodiment shown in FIG. 3 are identical to those in FIG. 2, which are not repeated herein.
As a variation of the embodiments shown in FIG. 2 and FIG. 3, the coils located at two ends of the pump body 31 also may supply power alternately and alternately generate an electromagnetic field having an attractive force on the piston having a magnet. Preferably, the two coils are supplied with a direct current, so as to easily control magnetic fields generated by the coils.
As another variation of the embodiments shown in FIG. 2 and FIG. 3, the piston no longer includes a magnet, but is made of iron, and when one of the two coils located in the pump body 31 is powered, the magnetic field generated by the coil generates an attractive force on the piston made of iron, and the piston moves towards the coil; when the coil on the other end is powered, the piston moves towards the other coil on the other end of the pump body, and reciprocate in this way so that the vacuum pump sucks air from the storage space and exhausts the air to the outside.
FIG. 4 is a schematic structural view of a vacuum pump 3a according to another preferred embodiment of the present invention. A difference between this embodiment and the embodiments shown in FIG. 2 and FIG. 3 lies in the position of the coil. In the embodiment shown in FIG. 4, the coil 38a surrounds the cylinder barrel 311 externally. When the coil 38a is powered (e.g., 220 V/230 V/110 V, 50 Hz/60 Hz), an electromagnetic field generated by the coil 38a may affect the piston 36 including a magnet.
Supposing at a certain moment, the electromagnetic field generated by the coil 38a makes the piston 36 move to the first end 315, at this time, the first cavity 301 is an exhaust stroke, and the second cavity 302 is a suction stroke; when the current is reversed, the piston 36 may move to the second end 316, at this time, the first cavity 301 is a suction stroke, and the second cavity 302 is an exhaust stroke. Due to the use of the alternating current, a change of the magnetic line of force is 50 Hz/s or 60 Hz/s, therefore the stroke of the piston 36 may not be great, and under the action of the middle reset magnet 40, the piston 36 can be located at a central position when in the stationary status.
In the above embodiment, if the stroke of the piston 36 is less than the lengths of the first cavity 301 and the second cavity 302, the shock attenuation magnets 391, 392 fixed on two ends of the pump body 31 also may be cancelled.
In the above embodiment, the shock attenuation device is formed by a magnet, however, in an alternative embodiment, the shock attenuation device 39 also may be formed by a spring connected to the piston 36, for example, a spring disposed in the first cavity and/or the second cavity and connected to the piston 36.
In the above embodiment, the vacuum pump includes two air inlets and two air outlets, however, the present invention should not be limited thereto, and may have other embodiments. For example, in the embodiment shown in FIG. 5, the vacuum pump 3b only includes a pair of air inlet 321 and air outlet 331 communicating with the first cavity 301. The second cavity 302 is kept in communication with air, and an air inlet capable of communicating with the storage space 2 is no longer included. The coil 38b capable of being supplied with an alternating current is fixed to the first end 315 having an air inlet 321 and an air outlet 321 at the pump body 31. When the current supplied to the coil 38b is forward, a magnetic field generated by the coil 38b generates an attractive force on the piston 36 including a magnet, so that the piston 36 moves towards the first end 315, the first cavity 301 is an exhaust stroke, the air inlet 321 is closed, and the air outlet 331 is opened; when the current supplied to the coil 38b is reversed, the magnetic field generated by the coil 38b generates a repellent force on the piston 36 including a magnet, so that the piston 36 moves towards the second end 316 to make the first cavity 301 sucks air from the storage space 2 through the opened air inlet 321, and at this time, the air outlet 331 is closed.
As shown in FIG. 5, the vacuum pump 3b may include shock attenuation springs 391b, 392b respectively connected between a corresponding side of the piston 36 and the first end 315 or the second end 316.
The embodiment shown in FIG. 6 serves as a variation of the embodiment shown in FIG. 5, and the coil 38c located at the first end of the pump body 31 is intermittently supplied with a direct current. When the coil 38c is powered, a magnetic field generated by the coil 38c generates an attractive force on the piston 36 including a magnet, so that the piston 36 moves towards the first end, the first cavity 301 is an exhaust stroke, the air inlet 32 is closed, and the air outlet 33 is opened; when the coil 38c is disconnected, the piston 36 moves towards the second end of the pump body 31 under the repellent force of the shock attenuation magnet 391. Preferably, the repellent force of the shock attenuation magnet 391 on the piston 36 also may act on the piston 36 located at the rightmost end of the pump cavity 30. The docking position of the piston 36 and the stroke of the piston 36 may be determined depending on a joint force of the magnet on the piston 36 and the shock attenuation magnet 391.

In the embodiment shown in FIG. 6, the refrigerator may further include a reset magnet 40 located at a middle position of the pump body 31.

REFERENCE NUMERALS

Refrigerator 1	Inner space 10
Storage unit 11	Air exhaust system 12
Storage space 2	Vacuum pump 3, 3a, 3b, 3c
Air exhaust path 4	Mechanical valve 8
Detection unit 9	Branch 5
Solenoid valve 7	Controller 6
Pump cavity 30	Pump body 31
Air inlet 321, 322	Air outlet 331, 332
Piston 36	Cylinder barrel 311
End cover 3121, 3122	First cavity 301
Second cavity 302	Air inlet check valve 323
Air exhaust check valve 333	Coil 381, 382, 38a, 38b, 38c
First end 315	Second end 316
Shock attenuation magnet 391, 392	Reset magnet 40
Shock attenuation spring 391b, 392b

Claims

A refrigerator (1), comprising:
a storage space (2) capable of keeping a low-pressure state;

a vacuum pump (3, 3a, 3b, 3c), comprising a pump body (31) for defining a pump cavity (30), an air inlet (321, 322) communicating with the pump cavity (30), an air outlet (331, 332) communicating with the pump cavity (30), a piston (36) accommodated in the pump cavity (30), and a driving device for driving the piston (36) to move in the pump cavity (30); and

an air exhaust path (4), connected to the storage space (2) and the air inlet (321, 322),

characterized in that:
the driving device comprises a coil (381, 382, 38a, 38b, 38c), wherein the coil (381, 382, 38a, 38b, 38c) is capable of generating an electromagnetic force for driving the piston (36) to move in the pump cavity (30), to suck air in the storage space (2) into the pump cavity (30) via the air inlet (321, 322) and discharge air out of the pump cavity (30) via the air outlet (331, 332).
The refrigerator (1) according to claim 1, characterized in that, the coil (381, 382, 38a, 38b, 38c) is fixed to the pump body.
The refrigerator (1) according to claim 1 or 2, characterized in that, the coil (38a) is disposed around the pump cavity (30).
The refrigerator (1) according to claim 1 or 2, characterized in that, the coil (381, 382, 38b, 38c) is fixed to an end portion of the pump body (31).
The refrigerator (1) according to claim 4, characterized by further comprising two groups of coils (381, 382) each fixed to a corresponding end of the pump body (31).
The refrigerator (1) according to claim 5, characterized in that, the two groups of coils (381, 382) supply power simultaneously or alternately.
The refrigerator (1) according to any one of claims 1 to 6, characterized in that, the pump body (31) comprises a cylinder barrel (311) and an end cover (3121, 3122) connected to an end portion of the cylinder barrel (311), and the air inlet (321, 322) and/or the air outlet (331, 332) is located on the end cover (3121, 3122).
The refrigerator (1) according to any one of claims 1 to 7, characterized in that, the pump body (31) comprises a first end (315) and a second end (316) opposite each other, the piston (36) is located between the first end and the second end, and the first end and the second end are each disposed with at least one air inlet (321, 322) and at least one air outlet (331, 332).
The refrigerator (1) according to claim 8, characterized in that, the air exhaust path (4) comprises a multi-way pipe connected to each of the air inlets (321, 322), and the multi-way pipe comprises a plurality of branches connected in parallel and each connected to each of the air inlets (321, 322).
The refrigerator (1) according to any one of claims 1 to 7, characterized in that, the pump body (31) comprises a first end (315) and a second end (316) opposite each other, the piston (36) is located between the first end (315) and the second end (316), the first end (315) is disposed with at least one air inlet (321) and at least one air outlet (331), and the second end (316) is kept in communication with air.
The refrigerator (1) according to any one of claims 1 to 10, characterized in that, the piston (36) comprises a magnet.
The refrigerator (1) according to any one of claims 1 to 11, characterized by further comprising a shock attenuation device (391, 392, 391b, 392b) for buffering a motion of the piston (36).
The refrigerator (1) according to claim 12, characterized in that, the shock attenuation device comprises a magnet and/or a spring connected to the piston.
The refrigerator (1) according to any one of claims 1 to 13, characterized by further comprising a reset magnet (40) provided along a middle portion of the pump cavity (30).