CN101389861A

CN101389861A - Linear compressor and drive unit therefor

Info

Publication number: CN101389861A
Application number: CNA2007800068638A
Authority: CN
Inventors: J-G·舒伯特
Original assignee: BSH Bosch und Siemens Hausgeraete GmbH
Current assignee: BSH Hausgeraete GmbH
Priority date: 2006-02-28
Filing date: 2007-01-09
Publication date: 2009-03-18
Also published as: DE102006009232A1; EP1991777A1; WO2007098970A1; PL1991777T3; EP1991777B1; US20090129955A1; RU2429376C2; RU2008135043A

Abstract

The drive unit for a linear compressor comprises a frame (1) and an oscillation body (12), connected to the frame (1) by means of a membrane spring (6) and guided to move back and forth in relation to the frame in a straight line. A coil spring (17) is connected to the oscillation body (12) and the frame and may be extended and compressed in the direction of the movement.

Description

Linear compressor and driver element thereof

Technical field

The present invention relates to linear compressor, it is particularly useful for the refrigeration agent in the compression refrigerating apparatus; And relate to the driver element that the oscillating piston that is used to drive this linear compressor moves.

Background technique

Patent publication us US6596032B2 discloses a kind of linear compressor, and its driver element comprises framework and is installed in oscillating body in the described framework via diaphragm spring.Oscillating body comprises permanent magnet; Be rigidly connected to the piston rod of described permanent magnet; And being connected to the piston of piston rod by knuckle joint, wherein said piston can to-and-fro motion in cylinder body.The electromagnet that the moving through of piston is placed in around the cylinder body is driven, wherein said electromagnet and permanent magnet interaction.The disc-shaped membrane flat spring is screwed on the central authorities of piston rod, and the outer rim of diaphragm spring is connected to fork, wherein said fork encirclement cylinder body, electromagnet and permanent magnet.

Compare with the spring of many other types, diaphragm spring has such advantage, and it can only be out of shape with respect to orientation of oscillation with meeting at right angles difficultly.Therefore, oscillating body can only move in the mode with one degree of freedom, and unlike the oscillating body that suspends from helical spring, for example it always has the three degree of freedom of translational motion, and if motion be limited to single degrees of freedom and require guide.This guide need not to be used to be bearing in the oscillating body on the diaphragm spring.Therefore, the moving of the piston that the moving of this oscillating body can convert in the mode of low frictional loss in the compressor, wherein said piston must be directed along the path of strict straight line.

Oscillating body and diaphragm spring have formed oscillatory system, and its resonant frequency is determined by the quality of oscillating body and diaphragm spring and the rigidity of diaphragm spring.Diaphragm spring allows only little oscillation amplitude, and this is because each deflection of oscillating body is relevant with the stretching, extension of diaphragm spring.Less oscillation amplitude means, is difficult to make that reliably the dead volume (dead volume) of cylinder body is less.Yet dead volume is big more, and the efficient of compressor is just low more.Short stroke makes that also cylinder body is configured to have the diameter bigger with respect to length, thereby realizes specific performance properties.Arm and a leg is the corresponding bigger piston periphery of sealing.

Another selection that increases performance be with diaphragm spring make unusual rigidity, thereby increase resonant frequency.Yet the rigidity of diaphragm spring is big more, means that also the danger that stands to lose efficacy at specific oscillation amplitude spring is just big more.This means, for fear of inefficacy, if spring rate is big more amplitude must be caught more little, thereby by this way non-availability can in this gratifying increase.

Summary of the invention

The purpose of this invention is to provide a kind of driver element that is used for linear compressor, comprise framework and oscillating body, wherein said oscillating body is installed in the described framework via diaphragm spring, wherein said diaphragm spring allows the dangerous big stroke of not losing efficacy of oscillating body, thereby can obtain high-performance at the small piston diameter.

The realization of this purpose is that except diaphragm spring helical spring is connected to oscillating body and framework, and can extend and compression along the direction that moves.Thereby can separately guide the function of oscillating body and the function of interim storage kinetic energy.Helical spring only is suitable for the line constraint oscillating body that limits along accurately a little, but is not difficult it is sized to keep the amplitude of the expectation of moving of oscillating body and the desired frequency that moves, and does not have the danger of material failure.Diaphragm spring must have only little material thickness, thereby obtains the big oscillation amplitude of expectation.This diaphragm spring will only allow the lower resonant frequency of oscillating body, if diaphragm spring is the sole body that must finish interim energy memory function.Yet by connecting the spring of two types abreast, all three requirements can be implemented simultaneously, that is to say accurate guiding at oscillating body, significantly and the requirement of high oscillation frequency.

Ideally, each spring should only apply power and not apply torque on oscillating body.For this reason, preferably around the straight line setting of the imagination, wherein the center of gravity of oscillating body can realize to-and-fro motion along the straight line of the described imagination to helical spring.Straight line preferably overlaps with helical spring longitudinal axis.

In order to prevent that diaphragm spring from applying torque or in order to minimize this torque, diaphragm spring preferably has the axis of symmetry that overlaps with straight line, or straight line position symmetry plane thereon.

In order to be transferred to oscillating body and without any torque, a helical spring end preferably acts on the periphery of latch plate from helical spring power, and oscillating body is connected to the center of latch plate.

In order to make diaphragm spring be out of shape a little along movement direction, it preferably has a plurality of bend arms, and an end of each arm is fixed to framework and the other end is fixed to oscillating body.

In order to improve the precision that oscillating body guides along straight line, at least two diaphragm springs preferably are set, they act on along on the zone of the oscillating body of vibration movement direction separation.

Theme of the present invention or linear compressor, it comprises the working room; Thereby in described working room, finish the piston of to-and-fro motion compression working fluid; And driver element as defined above, wherein said driver element is connected to described piston to drive described to-and-fro motion.In order to make this linear compressor compactness, advantageously partly surround by spiral winding for the working room.

Description of drawings

To know other characteristics of the present invention and advantage by the reference accompanying drawing from the explanation of following illustrative examples, wherein:

Fig. 1 shows the perspective view according to linear compressor of the present invention;

Fig. 2 shows a diaphragm spring in two diaphragm springs of linear compressor of Fig. 1;

Fig. 3 shows along the schematic cross sectional views of the linear compressor of imagination straight line G;

Fig. 4 shows the optional embodiment of the diaphragm spring of linear compressor; And

Fig. 5 shows another simplified embodiment of diaphragm spring.

Embodiment

The framework 1 of linear compressor comprises substrate 2, is extended with the

protuberance

3,4,5 of plate or rib form from described substrate.Such as shown in Figure 2 two diaphragm springs 6 are screwed on the narrow side of two protuberances 3 in opposite directions.Diaphragm spring 6 comprises edge section 7 respectively, and wherein said edge section seating the end face of protuberance 3, is extended with Z-shaped or S shape elastic arm (spring arm) 8 from the end of described edge section.Meeting in the central section 9 of diaphragm spring 6 each other in each end away from the elastic arm 8 of edge section 7, forms three

holes

10,11 in described central section.Oscillating body 12 utilizes screw or rivet (not shown) fixing between two diaphragm springs 6, and wherein said screw or rivet extend through the upper-side hole and the lower-side hole 10 of diaphragm spring 6.Hole 11 has formed the passage that is used for piston rod 13, and described piston rod extends between at oscillating body 12 and by the compressor assembly 14 of protuberance 5 carrying.

Two electromagnets 15 are arranged on every side of permanent magnetism oscillating body 12 and are in the hollow space that is surrounded by protuberance 3 and diaphragm spring 6, the described electromagnet and electric current can be flowed through, thereby between them, produce reciprocal magnetic field, described magnetic field make oscillating body 12 from it as shown in Figure 1 along the equilibrium position deflection (deflect) of straight line G, described straight line is along the center of gravity of or other direction extend past oscillating body 12.

Straight line G is extend past piston rod 13 and compressor assembly 14 vertically, and forms the axis of symmetry of two latch plates 16 simultaneously, and wherein said latch plate is being pressed against the outer side surface of two diaphragm springs 6 by helical spring 17.Fig. 3 shows along the longitudinal sectional view of the linear compressor of this straight line G.Latch plate 16 has spine respectively, and described spine extends around the edge of the recessed side that deviates from from diaphragm spring 6, and described spine is the fixing last lap of the helical spring 17 of seating on latch plate 16 radially.The opposite ends of helical spring 17 is fixed by the protuberance that extends in spring respectively.Smooth protuberance on the plate 4 that protuberance is a framework 1; Another protuberance 19 is parts of compressor housing 14.

Helical spring 17 extends between latch plate 16 and their protuberance 18 or 19 of supporting respectively, thereby at the non-return some place that moves of oscillating body 12, one of helical spring 17 is not tensioning.Therefore, helical spring 17 pushes latch plate 16 consistently and abuts against diaphragm spring 6, even is operating and oscillating body 12 when vibrating at compressor.Therefore, need not the diaphragm spring 6 that latch plate 16 is fixed to their contacts, thereby keep contact constant between them.Because the power of spring 17 acts on each latch plate 16 in the whole zone of latch plate 16 in quite equally distributed mode, so low torque causes making that the axle of latch plate tilts with respect to straight line G.Yet even this torque occurs, because do not have physical connection between latch plate 16 and diaphragm spring 6, this torque is not transferred to diaphragm spring.Because latch plate 16 is towards diaphragm spring 6 constrictions, thus they the power of helical spring 17 G very closely along the line is transferred in the diaphragm spring 6, thereby even because power heterogeneous distributes on the diaphragm spring 6 that is caused the torque of effect still less.Therefore, diaphragm spring 6 and the oscillating body 12 that supported by them only bear roughly exactly the power that aligns along the direction of straight line G by helical spring 17, and do not have to excite outer the moving of the online G of center of gravity of oscillating body 12.

The height symmetry of two diaphragm springs 6 also helps them to guide oscillating body 12 exactly along the line.

The schematic representation of Fig. 3 also shows the internal structure of compressor assembly 14.Can in the inner room 20 of compressor assembly 14, realize to-and-fro motion by the piston 21 that piston rod 13 is kept, thereby will also export refrigerant compressed in the refrigeration agent suction chamber 20 once more at pressure tube 23 places via suction pipe 22.The annular space 24 of extension is communicated with pressure tube 23 in cup-shaped around chamber 20.The edge of piston 21 was brushed along the partition wall 25 between chamber 20 and the annular space 24, formed a plurality of narrow passages 26 in described partition wall, and some refrigerant compressed can flow out from annular space 24 by described narrow passage gets back in the chamber 20.The refrigeration agent that returns forms the air cushion between the edge of partition wall 25 and piston 21, and this air cushion has prevented that piston 21 from contacting with direct friction between the partition wall 25 and be so the wearing and tearing maintenance of compressor assembly 14 is lower.By means of the accurate oscillating body 12 of guiding in straight line, described straight-line pass being by diaphragm spring and suspending of

helical spring

6,17 and obtained, and the low gas flow rates in the passage 26 are enough to produce and efficiently prevent the air cushion that rubs.

For the incorrectness a little that aligns mutually of compensation drive unit and compressor assembly, otherwise this also can cause piston 21 to rub on wall 25, and two deflectable point of weakness 27 of elasticity form in piston rod 13.The deflection a little of these point of weakness 27 make the center of gravity can compensate oscillating body 12 along the little deviation between the central longitudinal axis of its straight line G that moves and chamber 20 or even compensate non-parallel degree a little between the two.

The simple embodiment of diaphragm spring is shown in the Figure 4 and 5.The spring 6 of Fig. 4 ' roughly corresponding to half diaphragm spring among Fig. 3 only has two and bends to S shape or Z-shaped arm, and described arm extends to central section 9 from edge section 7.Spring 6 at Fig. 5 " in, crooked arm is by straight-arm 8 " to be replaced.Although strictly speaking, the free end of described straight-arm be inaccurate along straight line but move along camber line, but this deviation is insignificant in following situation, if the amplitude of oscillating body is constrained to, the cross component that moves of oscillating body is less than piston transverse movement.

Claims

1. driver element that is used for linear compressor, comprise framework (1) and oscillating body (12), wherein said oscillating body is connected to described framework (1) and guides into permission by at least one diaphragm spring (6) and carries out straight reciprocating motion with respect to described framework, it is characterized in that, helical spring (7) acts on described oscillating body (12) and the described framework, and can extend and compression along movement direction.

2. driver element according to claim 1 is characterized in that, described helical spring (17) extends on every side at straight line (G), can move in to-and-fro motion along the center of gravity of the described oscillating body of described straight line (12).

3. driver element according to claim 2 is characterized in that, described straight line (G) overlaps with the longitudinal axis of described helical spring (17).

4. according to claim 2 or 3 described driver elements, it is characterized in that described straight line (G) is the axis of symmetry of described diaphragm spring (6) or the part of the axis of symmetry.

5. according to the arbitrary described driver element of aforementioned claim, it is characterized in that an end of described helical spring (17) acts on the periphery of latch plate (16), described oscillating body (12) is being pressed at the center of wherein said latch plate.

6. according to the arbitrary described driver element of aforementioned claim, it is characterized in that described diaphragm spring (6) comprises a plurality of bend arms (8), an end of each arm is fixed to described framework (1) and the other end (9) are fixed to described oscillating body (12).

7. driver element according to claim 6 is characterized in that, each arm (8) has two sections along the different direction bending.

8. according to the arbitrary described driver element of aforementioned claim, it is characterized in that, also comprise secondary diaphragm spring (6) at least, and first and second diaphragm springs (6) act on the zone of the described oscillating body (12) that the direction that moves along vibration separates.

9. a linear compressor comprises working room (20); In described working room (20) thus in finish the piston (21) of to-and-fro motion compression working fluid; And according to the arbitrary described driver element of aforementioned claim, wherein said driver element is connected to described piston (21) and realizes described to-and-fro motion to drive.

10. linear compressor according to claim 9 is characterized in that, piston rod (13) extends between described piston (21) and described oscillating body (12) along described straight line (G).

11., it is characterized in that described working room (20) are surrounded by described helical spring (17) at least in part according to claim 9 or 10 described linear compressors.