JP2019051193A - Washing machine - Google Patents

Abstract

To achieve a washing machine which includes a vibration isolating device which can efficiently reduce vibration transmission ratio from a water tub to an outer frame and which can suppress vibration of the outer frame occurring especially during a normal dewatering operation.SOLUTION: A washing machine includes: a drum 34 rotatably supported in the direction of a rotary shaft which is horizontal or inclined and for accommodating objects to be washed; a water tub 33 for accommodating the drum 34; an outer frame 30 for accommodating the water tub 33; a driving part 36 for rotationally driving the drum 34; and a vibration isolating device 31, disposed between a bottom part of the water tub 33 and a bottom part of the outer frame 30, for elastically supporting the water tub 33 with respect to the outer frame 30. The vibration isolating device 31 comprises: a main elastic body 51 for supporting the water tub 33; and a damping part 52 connected to the main elastic body 51 in parallel. The damping part 52 includes a damper 54 and a sub elastic body 53, and it is constituted by the damper 54 and the sub elastic body 53 being connected in series, and it can suppress the vibration of the outer frame 30 occurring especially during a normal dewatering operation.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a washing machine that performs a washing operation on clothes accommodated in a drum rotatably disposed in a water tank.

  The conventional washing machine is provided with a vibration-proof damper at the bottom of the water tank, so that the vibration of the water tank and the outer frame is reduced (see, for example, Patent Document 1).

  FIG. 7 is a cross-sectional view of a main part of a conventional washing machine. As shown in FIG. 7, the vibration isolator 131 is disposed between the bottom portion 130 a of the outer frame 130 of the washing machine and the bottom portion 133 a of the water tank 133. The vibration isolator 131 is a viscous damper that uses oil as a working fluid, and reduces the resonance vibration amplitude of the water tank 33 at the start of dehydration. The legs 141 are made of an elastic material such as rubber, and are arranged at the four corners of the bottom 130 a of the outer frame 130. With these configurations, the vibration of the water tank 133 is not transmitted as it is to the bottom 30a of the outer frame 30, and the vibration of the outer frame 130 of the washing machine, the noise caused by the vibration, and the vibration of the floor can be reduced.

JP 2011-167222 A

  However, in the conventional configuration described in Patent Document 1, the use of a vibration isolator having a strong damping force is effective in suppressing the resonance amplitude of the aquarium at a low rotational speed, but the stationary outer frame at a high rotational speed. This increases vibration and increases steady vibration during dehydration operation. On the other hand, if a vibration isolator having a weak damping force is used, it is effective for suppressing steady vibration of the outer frame, but the effect of suppressing resonance becomes small, and the start-up rate during the dehydration operation tends to be reduced. That is, there is a problem that it is difficult to achieve both the suppression of the tank resonance by adjusting the damping force and the steady vibration suppression of the outer frame.

  In addition, the washing machine described in Patent Document 2 reduces the damping force at high speed rotation compared to low speed rotation to reduce vibration transmission from the water tank to the outer frame at steady vibration, and steady operation at high speed rotation. It is intended to reduce the vibration of the outer frame during operation. However, this conventional configuration requires a complicated structure for adjusting the damping force. In addition, since the load of the water tank acts directly on the outer frame via the vibration isolator, the vibration obtained by the change in the damping force of the vibration isolator compared to increasing the mass of the water tank or reducing the support rigidity There was a problem that the effect of reducing the transmission rate was small.

  The present invention solves the above-described conventional problems, and includes a vibration isolator capable of efficiently reducing the vibration transmission rate from the water tank to the outer frame, and suppresses vibration of the outer frame that occurs particularly during dehydration operation. An object is to provide a washing machine.

In order to solve the above-described conventional problems, a washing machine of the present invention has a horizontal or inclined rotating shaft and is rotatably supported, and a drum for storing an object to be cleaned such as clothes, and a water tank for storing the drum. And an outer frame that houses the water tank, a drive unit that rotationally drives the drum, and a vibration isolator that is disposed between the bottom of the water tank and the bottom of the outer frame and elastically supports the water tank. The vibration isolator comprises a main elastic body that supports the water tank and a damping part connected in parallel to the main elastic body, the damping part comprising a damper and a sub-elastic body, The auxiliary elastic body is configured by being connected in series.

  With this configuration, the vibration of the water tank is transmitted to the damper via the secondary elastic body included in the damping portion of the vibration isolator. For this reason, a difference arises in the state of the stroke at the time of damping between the main elastic body and the damping part. Thereby, the vibration transmission rate can be reduced by changing the damping force transmitted from the water tank to the outer frame and appropriately selecting the rigidity and damping force of the vibration isolator. In particular, during steady-state vibration during dehydration operation, the excitation force due to the load of the water tank is transmitted to the damper via a secondary elastic body that expands and contracts, reducing the vibration force transmitted from the water tank to the outer frame, In addition, the vibration of the house can be effectively suppressed.

  The washing machine of the present invention provides a vibration transmission characteristic by providing a damping part in parallel with the main elastic body supporting the water tub in the vibration isolator, and arranging a secondary elastic body in series with the damper in the damping part. It is possible to effectively reduce the vibration transmission rate from the water tank to the outer frame. In particular, it is possible to suppress vibrations of the outer frame and the floor at the steady state during the dehydration operation in which the drum is rotated at a high rotational speed.

Side surface sectional drawing of the washing machine in Embodiment 1 of this invention Sectional drawing of the principal part of the vibration isolator of the washing machine in Embodiment 1 of this invention The figure which shows the vibration model of the vibration isolator of the washing machine in Embodiment 1 of this invention. The characteristic view which shows the vibration transmissibility of the vibration isolator of the washing machine in Embodiment 1 of this invention Sectional drawing of the principal part of the vibration isolator of the washing machine in Embodiment 2 of this invention Sectional drawing of the principal part of the vibration isolator of the washing machine in Embodiment 3 of this invention Side sectional view of a conventional washing machine

  A washing machine according to a first aspect of the present invention is supported rotatably in the direction of a horizontal or inclined rotating shaft, and stores a drum for storing an object to be cleaned such as clothes, a water tank for storing the drum, and an outer space for storing the water tank. A frame, a drive unit that rotationally drives the drum, and a vibration isolator disposed between the bottom of the water tank and the bottom of the outer frame and elastically supporting the water tank with respect to the outer frame, The vibration isolator comprises a main elastic body that supports the water tank and a damping part connected in parallel to the main elastic body, and the damping part includes a damper and a sub-elastic body, and the damper and the sub-elasticity It is a washing machine configured by connecting bodies in series.

  With this configuration, the excitation force related to the load of the water tank from the water tank to the outer frame is transmitted to the damper via the secondary elastic body. The vibration transmission characteristic is changed by changing the transmission path of the excitation force from the water tank to the outer frame by the combination of the damping part and the main elastic body configured by connecting the auxiliary elastic body and the damper in series. Thereby, the reduction rate of the vibration transmissibility when the number of revolutions of the drum is high can be greatly improved as compared with the case where there is no secondary elastic body. Therefore, the higher the number of revolutions of the drum, the lower the vibration transmission rate from the water tank to the outer frame, and the outer frame vibration during the dehydration steady operation can be effectively reduced.

  According to a second aspect of the invention, in particular, in the first aspect of the invention, the secondary elastic body is set to have a total length shorter than a length of the main elastic body when fully compressed, and the secondary elastic body has an outer diameter of the main elastic body. The inner diameter of the main elastic body is set to be smaller than the inner diameter of the main elastic body.

  Even if it is the structure which added the subelastic body by this structure, it can suppress to the same level as before, without extending the external size of a vibration isolator. In addition, the secondary elastic body is not fully compressed when the main elastic body is fully compressed, and the generation of noise in the secondary elastic body can be prevented.

  In a third aspect of the invention, in particular, in the second aspect of the invention, the damper includes a cylinder, a piston that reciprocates in the cylinder, and a rod that is fixed to the piston and protrudes from one end surface of the cylinder, and the main elasticity The body includes a first spring receiver disposed on the one end surface side of the cylinder, and a second spring disposed on the tip end side of the rod so that the rod is slidable and fixed to the water tank. The auxiliary elastic body is disposed between the second spring receiver and the rod, and is disposed closer to the cylinder than the second spring receiver. The second spring support includes a hollow cylindrical portion through which the rod penetrates and the auxiliary elastic body is disposed outside, and the second spring support has a length of the hollow cylindrical portion. Is configured to be shorter than the length of the secondary elastic body when fully compressed. .

  With this configuration, the hollow cylindrical portion can prevent the secondary elastic body from being bent due to the lateral vibration of the water tank, and can be regulated so that the secondary elastic body can normally stroke without contacting the rod. In addition, by making the length of the hollow cylindrical portion shorter than the length at the time of full compression of the secondary elastic body, the vertical amplitude of the water tank is increased, and even when the secondary elastic body is fully compressed, the hollow cylindrical portion is Therefore, it is possible to prevent the generation of abnormal noise in the vibration isolator.

  According to a fourth aspect of the present invention, in the second aspect of the present invention, in the second aspect, the damper includes a cylinder, a piston that reciprocates in the cylinder, and a rod that is fixed to the piston and protrudes from one end surface of the cylinder. The body includes a first spring receiver disposed on the one end face side of the cylinder, and a second spring fixed to the water tank, the rod being slidable on the tip end side of the rod. The secondary elastic body is disposed between the second spring receiver and the rod, and is arranged between the second spring receiver and the third spring receiver. The auxiliary elastic body is constituted by a hollow cylindrical viscoelastic body through which the rod passes.

  With this configuration, the viscoelastic body also has a function of restricting the sliding of the rod, and it is not necessary to provide a hollow cylindrical portion in the second spring support to restrict the sliding of the rod, thereby simplifying the components. Further, by using a hollow cylindrical viscoelastic body as the secondary elastic body, a damping force can be applied to the vibration isolator not only in the vertical direction but also in the horizontal direction. Thereby, the vibration isolator can effectively suppress the vibration in the lateral direction of the water tank at the time of resonance of the water tank that occurs when the rotation speed of the drum is low.

  In a fifth aspect of the present invention, in particular, in the first aspect, the damper includes a cylinder, a piston that reciprocates in the cylinder, and a rod that is fixed to the piston and protrudes from one end surface of the cylinder. The body includes a first spring receiver disposed on the one end face side of the cylinder, and a second spring receiver disposed on the tip end side of the rod so as to be integrated with the rod and fixed to the water tank. The secondary elastic body is disposed inside the cylinder.

  With this configuration, the secondary elastic body is provided in the cylinder, so that the secondary elastic body can be expanded and contracted without being bent in the cylinder, and a vertical damping force can be appropriately applied to the vibration isolator. In addition, the rod and the second spring support can be integrated, and the stroke space of the rod from the second spring support to the water tank side becomes unnecessary, and it is easy to secure the mounting space for the vibration isolator. Further, by integrating the rod with the second spring support, it is possible to prevent the generation of noise due to contact between the rod and other parts.

In a sixth aspect of the invention, in particular, in any one of the first to fifth aspects of the invention, the sub elastic body has higher rigidity than the main elastic body. With this configuration, when the drum rotation speed is low, the vibration of the secondary elastic body is relatively small, and the stroke amount of the main elastic body and the rod of the damper is almost equal, so that a damping force is easily generated by the damper, and the water tank The resonance amplitude can be kept small.

  In a seventh aspect of the invention, in particular, in any one of the first to sixth aspects of the invention, the main elastic body has a resonance frequency of the water tank that is a combination of the main elastic body and the sub-elastic body being a predetermined resonance frequency or less Thus, the rigidity is set low. With this configuration, it is possible to prevent the resonance frequency from becoming higher than before due to the insertion of the secondary elastic body, and also to reduce the vibration transmissibility during dehydration steady operation, and to reduce the vibration transmissibility over a wide frequency range. An effect is obtained.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the thing of the same structure as a prior art example attaches | subjects the same code, and abbreviate | omits description. Further, the present invention is not limited by this embodiment.

(Embodiment 1)
1 is a side sectional view of a washing machine according to Embodiment 1 of the present invention. FIG. 2 is a cross-sectional view of a main part of the vibration isolator 31 of the washing machine in the present embodiment. FIG. 3 is a diagram showing a vibration model of the vibration isolator 31 of the washing machine in the present embodiment. FIG. 4 is a diagram showing the characteristics of the vibration transmissibility of the vibration isolator 31 of the washing machine in the present embodiment.

  The structure of the washing machine in Embodiment 1 of this invention is demonstrated. As shown in FIG. 1, the washing machine includes a water tank 33, a drum 34 that accommodates an object to be cleaned such as clothes provided in the water tank 33, and a drive unit that rotates the drum 34. 36 and a vibration isolator 31 that suppresses vibration of the outer frame 30. The direction of the rotation axis of the drum 34 is set in a horizontal direction or a direction in which the front side of the washing machine is inclined upward.

  The outer frame 30 elastically supports the water tank 33 from below by two vibration isolation devices 31. One end of the vibration isolator 31 is connected to the lower part of the water tank 33, and the other end of the vibration isolator 31 is connected to the bottom of the outer frame 30. The two anti-vibration devices 31 are provided at positions (not shown) that are substantially symmetrical in the left-right direction with respect to the center of gravity of the water tank 33. Moreover, the two vibration isolator 31 is provided on the substantially gravity center of the water tank 33 in the front-back direction. Moreover, the water tank 33 is provided with a plurality of ribs (not shown) on the outer side surface. Thereby, the rigidity of the water tank 33 is improved and the deflection in each direction is suppressed.

  A suspension device 32 made of a tension spring is provided between the upper portion of the outer frame 30 and the upper portion of the water tank 33. The suspension device 32 elastically suspends and supports the water tank 33 and maintains the posture of the water tank 33.

  The drum 34 is provided with an opening 43 through which an object to be cleaned such as clothes is put in and out of the front side of the washing machine. A balancer device (not shown) is disposed in the opening 43 of the drum 34. This balancer device automatically corrects unbalance during rotation of the drum 34 due to uneven distribution of the object to be cleaned in the drum 34, and suppresses vibration.

  The drive part 36 consists of a brushless DC motor, and a rotational speed is controlled by inverter control. The drive unit 36 is disposed below the water tank 33 and rotates the drum 34 via a speed reduction mechanism 37 including a motor pulley, a drive belt, and a drum pulley.

The washing water supply unit 38 is provided at an upper portion in the outer frame 30 and supplies washing water into the water tank 33 and the drum 34. The water level detection unit 39 detects the water level of the washing water in the water tank 33. The drainage part 40 is provided in the lower part of the water tank 33, and drains the washing water in the water tank 33 outside the apparatus. The operation display unit 42 is provided in the upper part of the front surface of the washing machine, and displays operation course setting operations and setting contents by the user. The control device 41 is provided on the bottom of the outer frame 30. The control device 41 includes the drive unit 36 and the washing water supply unit 3 based on the setting content input by the operation display unit 42.
8. The drainage unit 40 and the like are sequentially controlled to perform a series of washing operations such as a washing process, a rinsing process, and a dehydrating process.

  Next, the structure of the vibration isolator 31 of the washing machine in this Embodiment is demonstrated. As shown in FIG. 2, the vibration isolator 31 in the present embodiment is composed of a main elastic body 51 and an attenuation part 52. The main elastic body 51 and the damping part 52 are connected in parallel. The damping part 52 is composed of a damper 54 and a secondary elastic body 53. The damper 54 and the secondary elastic body 53 are connected in series.

  The vibration isolator 31 is provided below the water tank 33 and elastically supports the water tank 33 from the bottom of the outer frame 30.

  Similarly, if the water tank 33 can be supported, the vibration isolator 31 may be provided on the upper part of the water tank 33. Moreover, if the stability of the support with respect to the water tank 33 can be ensured for any situation during the operation of the washing machine, the number of the vibration isolation devices 31 may be increased or decreased, or the arrangement may be changed. . Further, the suspension device 32 at the top of the water tank 33 may not be provided.

  Further, an anti-vibration rubber or the like may be provided between the vibration isolator 31 and the water tank 33 and the outer frame 30 so that the slight vibration and noise of the water tank 33 do not easily propagate to the outer frame 30.

  In the present embodiment, coil springs are used for the main elastic body 51 and the secondary elastic body 53. The damper 54 is an oil damper. Alternative members such as air springs and magnetic fluid dampers may be used as long as they can add rigidity and damping.

  The main elastic body 51 has an expansion / contraction amount such that there is no line-to-line contact of the main elastic body 51 at a large amplitude such as the resonance amplitude at the maximum unbalance amount in the dehydration process. Note that the rigidity of the main elastic body 51 is desirably small as long as the necessary rigidity is ensured. The smaller the rigidity is, the lower the resonance frequency can be, the resonance amplitude is reduced, and the vibration transmissibility in the high rotation speed range is also reduced. However, the required rigidity is the deformation of the inlet around the opening 43, even if the water tank 33 sinks and the relative position with the outer frame 30 shifts at the maximum capacity of washing water and clothes. The rigidity is such that the piping for the water tank 33 is not affected.

  The secondary elastic body 53 has a natural length that is shorter than the length of the main elastic body 51 when fully compressed. Further, the secondary elastic body 53 is set so that the outer diameter is set smaller than the inner diameter of the main elastic body 51 and is included in the main elastic body 51. The rigidity of the secondary elastic body 53 is set to be about 2 to 5 times larger than the rigidity of the main elastic body 51. Thereby, it is comprised so that the resonance of the water tank 33 can be suppressed effectively.

  The oil damper as the damper 54 includes a cylinder 54a in which oil is enclosed, a piston 54b that reciprocates in the oil to generate a damping force due to viscous resistance, and a rod rod 54c fixed to the piston 54b. ing. The rod 54c protrudes from one end surface of the cylinder 54a.

  Next, the structure regarding fixation of the said various component which comprises the vibration isolator 31 is demonstrated. The main elastic body 51 is disposed so as to enclose the rod 54c between a first spring receiver 55 provided on one end face side of the cylinder 54a and a second spring receiver 56 provided on the distal end side of the rod 54c. Is done. The sub-elastic body 53 is disposed between the second spring receiver 56 and a third spring receiver 57 provided integrally with the rod 54 c on the cylinder 54 a side from the second spring receiver 56.

The first spring support 55 is arranged so that the first spring support 55 does not vibrate with respect to the cylinder 54a.
It is fixed to one end of the cylinder 54a. The second spring receiver 56 is fixed to the water tank 33 so that the second spring receiver 56 does not vibrate with respect to the water tank 33, and is not coupled to the rod 54c. The third spring receiver 57 is fixed to the rod 54c so that the third spring receiver 57 does not vibrate with respect to the rod 54c. The third spring receiver 57 may be welded to the rod 54c, or may be fixed via a part such as an E-ring.

  Note that the first spring receiver 55 does not need to be integrated with the cylinder 541 as long as it does not move relative to the cylinder 54 a due to vibration of the main elastic body 51, and is inserted so as to contact the cylinder 541. It may be. Similarly, the second spring support 56 need not be integrated with the water tank 33 as long as it does not move with respect to the water tank 33, and may be inserted so as to be in contact with the water tank 33.

  Further, the second spring support 56 is provided with a hollow cylindrical portion 56a through which the rod 54c passes. The hollow cylindrical portion 56a extends from the lower surface of the second spring receiver 56 toward the cylinder 54a. The secondary elastic body 53 is disposed outside the hollow cylindrical portion 56a. The length of the hollow cylindrical portion 56 a is configured to be shorter than the length of the secondary elastic body 53 when fully compressed. The inner peripheral surface of the hollow cylindrical portion 56a and the outer peripheral surface of the rod 54c are configured to be slidable.

  As long as it is slidable, the hollow cylindrical portion 56a may have a larger inner diameter than the outer diameter of the rod 54c, or may be grease applied to the sliding portion. Moreover, it is good also as a structure where the rod 54c can stroke by using the bearing for linear motion comprised separately from the 2nd spring receiver 56. FIG.

  About the washing machine comprised as mentioned above, the operation | movement and an effect | action are demonstrated.

  After the user puts clothes and detergent into the drum 34 and presses the start button, the washing operation is started. First, a washing process is performed. The control device 41 operates the washing water supply unit 38 so that the washing water is supplied into the drum 34. When the water level detection unit 39 detects that a specified amount of washing water has been supplied into the drum 34, the control device 41 sends a signal to the washing water supply unit 38 to stop water supply.

  The control device 41 drives the drive unit 36 to rotate the drum 34. As the drum 34 rotates, the detergent dissolves in the washing water and penetrates into the clothing. The control device 41 rotates the drum 34 at a low speed of about 30 r / min, and performs washing for lifting and dropping clothes for a predetermined time. After completion of the washing process, the control device 41 operates the drainage unit 40 to discharge the washing water in which the dirt is dissolved out of the water tank 33.

  The control device 41 operates the washing water supply unit 38 to supply a specified amount of washing water into the drum 34. Then, a rinsing process is performed in which the detergent and dirt left on the clothes are rinsed out of the clothes. As in the washing process, the control device 41 rotates the drum 34 at a low speed of about 30 r / min, and performs a predetermined time and a predetermined number of times to lift and drop the clothes. When the last rinse is completed and the last drainage of the rinse process is completed, the control device 41 starts the dehydration process.

  When the washing operation enters the dehydration process, the rotation of the drum 34 gradually increases. At this time, the clothes that are biased in the drum 34 are rotated to swing the drum 34, and the water tank 33 is vibrated as an excitation force. This vibration is generated in the circumferential direction of the rotating shaft of the drum 34. This vibration energy is transmitted through the vibration isolator 31 and vibrates the outer frame 30.

When the rotational speed of the drum 34 reaches approximately 150 r / min to 250 r / min, resonance of the water tank 33 occurs and the water tank 33 vibrates greatly. In this vibration mode, the horizontal amplitude and the vertical amplitude of the water tank 33 are increased. Since the vibration isolator 31 is installed below the water tank 33 in a substantially vertical direction, the damping force in the vertical direction is large, but the damping force in the horizontal direction is small, and the vibration in the horizontal direction is larger than that in the vertical direction.

  When the rotation speed of the drum 34 further increases and reaches the target rotation speed, dehydration steady operation is performed. In the steady operation of dehydration, the drum 34 continues to rotate for several minutes at a high rotational speed of 700 r / min to 900 r / min.

  The vibration during the steady operation of the dehydration process is not the resonance frequency of the water tank 33 or the outer frame 30. Moreover, although the drum 34 correct | amends the imbalance of clothes by a balancer, it is difficult to balance completely, and the eccentric load remains. Due to the vibration characteristics of the rotating machine, the drum 34 continues to generate vibration due to the eccentric load even when the rotation speed increases. The vibration of the water tank 33 and the outer frame 30 generated by the vibration of the drum 34 becomes unpleasant noise for the user and leads to a vibration of the house, which causes a problem. For this reason, it is important to reduce the vibration transmission rate from the water tank 33 to the outer frame 30.

  The above-described resonance suppression of the washing machine and reduction of vibration transmissibility in the steady state are in a trade-off relationship. In a conventional washing machine, in order to suppress both of them, a variable damping unit that changes the damping force of vibration by the vibration isolator 31 in accordance with the rotation speed of the drum 34 or the damper stroke of the vibration isolator 31 has been used. It was. For example, a damper mounting method or a damper structure in which a damper force is strengthened when the water tank 33 resonates when the rotation speed of the drum 34 is low and a damper force is weakened when the drum 34 is steady at a high rotation speed. Ingenuity has been devised.

  However, in terms of vibration characteristics, the improvement of the vibration transmissibility obtained by weakening the vibration damping force in a steady state becomes a second-order lag element. For this reason, the reduction degree of the vibration transmissibility in the high rotation speed range is limited to about −20 dB / dec. That is, the vibration transmissibility reduction effect obtained by weakening the vibration damping force is small.

  The vibration isolator 31 of the washing machine in the present embodiment is configured to be a vibration model as shown in FIG. That is, the vibration isolator 31 is caused by the main elastic body 51 and the attenuation part 52 connected in parallel thereto. In addition, the damping part 52 is constituted by a secondary elastic body 53 connected in series with the damper 54.

  Specifically, for example, as described above with reference to FIG. 2, the main elastic body 51 includes a first spring receiver 55 provided on the cylinder 54a side and a first water tank 33 provided on the tip of the rod 54c. Between the two spring receivers 56. The sub-elastic body 53 is disposed between the second spring receiver 56 and a third spring receiver 57 provided integrally with the rod 542 on the cylinder 541 side of the second spring receiver 56. The damper 54 is connected in series with the secondary elastic body 53 via the third spring support 57.

  With this configuration, it is possible to realize the vibration isolator 31 in accordance with the vibration model shown in FIG.

FIG. 4 is a characteristic diagram showing the vibration transmissibility of the vibration isolator 31 of the washing machine in the present embodiment. As shown in FIG. 4, in the case of a vibration model such as the vibration isolator 31 in the present embodiment, the vibration transfer characteristic is a third-order transfer function, and the vibration transfer rate is about −40 dB / in the high frequency region. dec. Since the conventional washing machine is not provided with the secondary elastic body 53, the drum 34 rapidly decreases when the rotation speed exceeds the resonance frequency of the water tank 33, and the higher the rotation speed, the lower the vibration transmissibility limit. (Indicated by a dotted line in FIG. 4). Further, when the rigidity of the main elastic body 51 is made equal to that of the prior art, the resonance amplitude can be maintained and the steady vibration transmissibility can be reduced only by inserting the sub elastic body 53, but the resonance frequency is increased and vibration transmission is performed. The rate improvement region becomes narrow (indicated by a broken line in FIG. 4).

  Therefore, the vibration isolator 31 of the present embodiment includes the auxiliary elastic body 53 and the rigidity of the main elastic body 51 is set lower than the conventional rigidity. As a result, the resonance frequency can be suppressed to the same level as in the prior art, and an improvement effect of the vibration transmissibility can be obtained over a wide frequency range (shown by a solid line in FIG. 4).

  As described above, according to the vibration isolator 31 of the present invention, it is possible to reduce the vibration transmission rate from the water tank 33 to the outer frame 30 or the floor surface at the time of steady vibration at a high rotational speed, and at the time of resonance at a low rotational speed. The resonance of 33 can be effectively suppressed.

  Further, in the vibration isolator 31 of the washing machine according to the present embodiment, the rigidity of the secondary elastic body 53 is set higher than the rigidity of the main elastic body 51. With this setting, the damper 54 is more rigidly connected to the water tank 33, and the water tank 33 and the damper 54 are likely to vibrate in the same phase. Therefore, when the rotation speed of the drum 34 is low and the water tank 33 resonates, the strokes of the main elastic body 51 and the damper 54 are substantially the same.

  On the other hand, during steady operation where the rotation speed of the drum 34 is high, the secondary elastic body 53 easily vibrates in a phase opposite to that of the water tank 33 because it is in a frequency range sufficiently higher than the resonance frequency of the water tank 33. Become. Therefore, a difference occurs in the stroke state of the main elastic body 51 and the damper 54.

  With this configuration, when the number of rotations of the drum 34 is low, the damper 54 functions as a vibration damping unit and effectively suppresses resonance. Moreover, when the rotation speed of the drum 34 is high, the vibration energy is hardly transmitted from the water tank 33 to the outer frame 30, and the vibration transmission rate can be reduced.

  Furthermore, with this configuration, it is possible to arbitrarily select which of the resonance suppression at the time of low rotation of the drum 34 and the reduction of the vibration transmissibility at the time of high rotation should be configured to constitute the vibration isolation device 31. . That is, in order to improve the effect of suppressing the resonance when the drum 34 rotates at a low speed, the spring constant ratio of the secondary elastic body 53 to the main elastic body 51 may be increased or the damping force by the damper 54 may be set large. On the other hand, if the vibration insulation effect in the steady operation state at high rotational speed is to be improved, the spring constant ratio of the secondary elastic body 53 to the main elastic body 51 may be reduced or the damping force by the damper 54 may be reduced. . In this way, the rigidity of the secondary elastic body 53 and the damping force of the damper 54 may be changed according to the target value for vibration.

  Further, in the vibration isolator 31 of the washing machine according to the present embodiment, the rigidity of the main elastic body 51 is lower than that of the conventional one, and the resonance frequency of the spring system by the main elastic body 51 and the auxiliary elastic body 53 is conventional. It is comprised so that it may become an equivalent frequency. Thus, by inserting the secondary elastic body 53 in addition to the main elastic body 51, the combined support rigidity of the spring system is improved, and the resonance frequency of the water tank 33 is prevented from increasing, and the resonance frequency is increased. An increase in resonance amplitude can be prevented. Therefore, it is possible to improve both the resonance suppression of the water tank 33 when the drum 34 rotates at a low speed and the effect of vibration isolation between the water tank 33 and the outer frame 30 when the drum 34 rotates at a high speed.

Further, in the vibration isolator 31 of the washing machine in the present embodiment, the total length, which is the natural length of the secondary elastic body 53, is set shorter than the length of the main elastic body 51 when fully compressed. The outer shape of the sub-elastic body 53 is set smaller than the inner diameter of the main elastic body 51, and the sub-elastic body 53 is arranged so as to be included in the main elastic body 51. As a result, the secondary elastic body 5 is fully compressed when the main elastic body 51 is compressed.
3 is not fully compressed, and it is possible to prevent the secondary elastic body 53 from generating abnormal noise. Further, the sub-elastic body 53 is configured in a shape that can be included in the main elastic body 51, so that the vibration isolator 31 can be suppressed to a conventional outer size.

  The second spring receiver 56 is provided with a hollow cylindrical portion 56a through which the rod 54c passes, and the secondary elastic body 53 is provided outside the hollow cylindrical portion 56a of the second spring receiver 56. . Accordingly, the rod 54c and the second spring support 56 are regulated so that the sliding is performed smoothly, and the rod 54c can move without resistance in the axial direction, and the damping force can be transmitted appropriately. Further, since the movement in the vertical direction with respect to the axis of the rod 54c is restricted, it is possible to prevent the main elastic body 51 and the secondary elastic body 53 from bending in the horizontal direction against the vibration in the horizontal direction. Further, since the third spring receiver 57 is integrated with the rod 54 c, the load applied to the auxiliary elastic body 53 can be transmitted to the rod 542 without loss.

  Further, the length of the hollow cylindrical portion 561 is configured to be shorter than the length at the time of full compression of the auxiliary elastic body 53 disposed outside the hollow cylindrical portion 56a. Thereby, the presence of the hollow cylindrical portion 56a prevents the secondary elastic body 53 from being bent due to the lateral vibration of the water tank 33, and the secondary elastic body 53 can be regulated so that it can normally stroke without contacting the rod 54c. . In addition, since the length of the hollow cylindrical portion 56a is shorter than the length of the secondary elastic body 53 during full compression, the longitudinal amplitude of the water tank 33 is increased, and even when the secondary elastic body 53 is fully compressed, the hollow cylindrical portion 56a is hollow. The cylindrical portion 56a does not come into contact with the third spring receiver 57, and the generation of abnormal noise in the vibration isolator 31 can be prevented.

  In the present embodiment, the main elastic body 51 is configured on the water tank 33 side, and the attenuation portion 52 is configured on the outer frame 30 side. However, the present invention is not limited thereto. For example, conversely, the damping part 52 may be configured on the water tank 33 side, and the main elastic body 51 may be configured on the outer frame 30 side.

(Embodiment 2)
In the washing machine according to Embodiment 2 of the present invention, the secondary elastic body 63 of the vibration isolator 31 is configured by a hollow cylindrical viscoelastic body. Other configurations are the same as those in the first embodiment, and a description thereof will be omitted.

  FIG. 5 is a cross-sectional view of a main part of a vibration isolator 31 for a washing machine according to Embodiment 2 of the present invention. As shown in FIG. 5, the configurations of the main elastic body 51 of the vibration isolator 31 and the damper 54 of the damping unit 62 are the same as those in the first embodiment.

  The structures of the secondary elastic body 63 of the second spring receiver 66 and the damping part 62 are different. The secondary elastic body 63 is disposed between the second spring receiver 66 and the third spring receiver 57, and is configured by a hollow cylindrical viscoelastic body. The rod 54c is configured to penetrate the hollow cylindrical portion 63a of the secondary elastic body 63. As the viscoelastic body of the secondary elastic body 63, for example, by using an anti-vibration rubber, it is possible to have different spring performance and damping performance in the three axial directions. As a result, a damping force can be applied in a direction perpendicular to the axis of the rod 54c while having the same rigidity as the sub-elastic body 53 of the first embodiment.

  Further, the second spring receiver 66 provided on the distal end side of the rod 542 and fixed to the water tank 33 does not include a hollow cylindrical portion. In the vibration isolator 31 of the present embodiment, the secondary elastic body 63 formed of a hollow cylindrical viscoelastic body has a function of restricting sliding of the hollow cylindrical portion 56a of the second spring receiver 56 in the first embodiment. By having both, the rod 54c of the damper 54 can be normally stroked in the axial direction.

Further, the secondary elastic body 63 can apply a damping force in a direction perpendicular to the axis of the rod 54c by the viscoelastic body, so that the moving load is absorbed by the viscoelastic body even if the rod 54c moves in the lateral direction. It is possible to apply a damping force against lateral vibration.

  Further, since the movement of the rod 54c in the lateral direction can be restricted, it is possible to prevent the main elastic body 51 and the secondary elastic body 63 from bending in the lateral direction. Further, since the third spring receiver 57 is integrated with the rod 54c, the load applied to the auxiliary elastic body 63 can be transmitted to the rod 54c without loss.

  In the washing machine, clothes thrown into the drum 34 by the user are unevenly distributed. Thereby, the drum 34 is rotated in a state in which an eccentric load due to clothing is generated. However, the excitation force generated by the imbalance during the rotation of the drum 34 varies with each operation. Therefore, the washing machine is required to have a damping force with respect to the lateral excitation force.

  In the washing machine of the present embodiment, a hollow cylindrical viscoelastic body is used as the secondary elastic body 63 of the vibration isolator 31, so that a damping force is applied not only in the vertical direction but also in the horizontal direction of the washing machine. Is done. Thereby, the vibration isolator 31 can effectively suppress vibrations in the vertical and horizontal directions of the water tank 33 at the time of resonance of the water tank 33 that occurs when the rotation speed of the drum 34 is low.

(Embodiment 3)
In the washing machine according to Embodiment 3 of the present invention, the secondary elastic body 73 of the vibration isolator 31 is disposed inside the cylinder 54 a of the damper 54. Other configurations are the same as those of the first embodiment, and the description thereof is omitted.

  FIG. 6 is a cross-sectional view of a main part of a vibration isolator 31 for a washing machine according to Embodiment 3 of the present invention. As shown in FIG. 6, the configuration of the main elastic body 51 of the vibration isolator 31 and the damper 54 of the damping unit 72 is the same as that of the first embodiment.

  The configurations of the second spring support 76 and the sub-elastic body 73 of the damping portion 22 are different. The secondary elastic body 73 is composed of a viscoelastic body such as a vibration-proof rubber, and is disposed in the cylinder 54a and inserted between the rod 54c and the piston 54b. The tip of the rod 54c is integrated with the second spring support 76 fixed to the water tank 33.

  The secondary elastic body 73 has the same rigidity as the secondary elastic body 53 of the first embodiment. The secondary elastic body 73 may be a coil spring as long as it is an elastic body having the same rigidity as that of the first embodiment. At this time, a spring receiver may be provided on the rod 54c or the piston 54b so that the coil spring can be properly expanded and contracted. Further, if the secondary elastic body 73 is disposed in the cylinder 54a, it does not need to be directly coupled to the piston 54b. For example, even if it is inserted between both parts of the rod 54c divided into the upper and lower parts. Good.

  In the washing machine of the present embodiment, the secondary elastic body 73 of the vibration isolator 31 is provided in the cylinder 54a, so that the secondary elastic body 73 can be expanded and contracted without being bent in the cylinder 54a. Thereby, the damping force of the vertical direction of a washing machine can be added appropriately.

  Further, since the rod 54c is integrated with the second spring support 76, the rod 542 is prevented from sliding in the hollow cylindrical shape in the first embodiment or in the second embodiment with respect to lateral vibration. There is no contact with the viscoelastic body. Accordingly, it is possible to prevent the generation of abnormal noise due to the contact between the rod 54c and other parts.

In the first and second embodiments, since the rod 54c extends and contracts through the second spring receivers 56 and 66, the space in which the rod 54c can stroke in the space closer to the water tank 33 than the second spring receivers 56 and 66. Was necessary. In the vibration isolator 31 of the present embodiment, by integrating the second spring support 76 and the rod 54c, a space in which the rod 54c can stroke in the space closer to the water tank 33 than the second spring support 76 becomes unnecessary. The mounting structure of the vibration isolator 31 on the water tank 33 side can realize an equivalent structure.

  As described above, the washing machine according to the present embodiment is configured such that the secondary elastic body 73 of the vibration isolator 31 is disposed in the cylinder 54 a, so that the longitudinal damping force is appropriately adjusted during the operation of the damper 54. And the generation of abnormal noise can be prevented. Moreover, the attachment structure of the vibration isolator 31 can also be simplified.

  As described above, the washing machine according to the present invention includes an anti-vibration device that can efficiently reduce the vibration transmission rate from the water tub to the outer frame, and suppresses vibration of the outer frame that occurs particularly during dehydration operation. Therefore, it is not only useful as a rotary drum type washing machine, but also in a washing and drying machine equipped with the same vibration isolator, a dedicated drying machine, and a vertical washing machine and a vertical washing machine. Applicable.

30 Outer frame 31 Vibration isolator 32 Suspension device 33 Water tank 34 Drum 36 Drive part 51 Main elastic body 52, 62, 72 Damping part 53, 63, 73 Secondary elastic body 54 Damper 54a Cylinder 54b Piston 54c Rod 55 First spring support 56, 66, 76 Second spring support 56a Hollow cylindrical portion 57 Third spring support 63a Hollow cylindrical portion

Claims (7)

A drum that is rotatably supported in the direction of a horizontal or inclined rotating shaft, and that contains an object to be cleaned such as clothing;
A water tank containing the drum;
An outer frame for housing the water tank;
A drive unit for rotationally driving the drum;
A vibration isolator disposed between the bottom of the water tank and the bottom of the outer frame and elastically supporting the water tank with respect to the outer frame;
The vibration isolator comprises a main elastic body that supports the water tank, and a damping unit connected in parallel to the main elastic body,
The damping portion includes a damper and a secondary elastic body,
A washing machine configured by connecting the damper and the secondary elastic body in series. The sub elastic body is set to have a total length shorter than the length of the main elastic body when fully compressed,
The secondary elastic body has an outer diameter set smaller than an inner diameter of the main elastic body,
The washing machine according to claim 1, wherein the washing machine is configured to be included in the main elastic body. The damper has a cylinder, a piston that reciprocates in the cylinder, and a rod that is fixed to the piston and protrudes from one end surface of the cylinder,
The main elastic body includes a first spring receiver disposed on the one end face side of the cylinder and a first spring receiver disposed on the tip end side of the rod so that the rod is slidable and fixed to the water tank. Between the two spring receivers, the rod is included and disposed,
The secondary elastic body is disposed between the second spring support and a third spring support that is integral with the rod and disposed closer to the cylinder than the second spring support.
The second spring support includes a hollow cylindrical portion through which the rod penetrates and the auxiliary elastic body is disposed outside,
The length of the said hollow cylindrical part is a washing machine of Claim 2 comprised from the length at the time of the total compression of the said secondary elastic body. The damper has a cylinder, a piston that reciprocates in the cylinder, and a rod that is fixed to the piston and protrudes from one end surface of the cylinder,
The main elastic body includes a first spring receiver disposed on the one end face side of the cylinder and a first spring receiver disposed on the tip end side of the rod so that the rod is slidable and fixed to the water tank. Between the two spring supports,
The secondary elastic body is disposed between the second spring support and a third spring support that is integral with the rod and disposed closer to the cylinder than the second spring support.
The washing machine according to claim 2, wherein the secondary elastic body is constituted by a hollow cylindrical viscoelastic body through which the rod passes. The damper has a cylinder, a piston that reciprocates in the cylinder, and a rod that is fixed to the piston and protrudes from one end surface of the cylinder,
The main elastic body includes a first spring receiver disposed on the one end face side of the cylinder, and a second spring fixed to the water tank disposed integrally with the rod on the tip end side of the rod. Arranged between the spring support and
The washing machine according to claim 1, wherein the sub-elastic body is disposed inside the cylinder. The washing machine according to any one of claims 1 to 5, wherein the sub-elastic body has higher rigidity than the main elastic body. The rigidity of the main elastic body is set to be low so that a resonance frequency of the water tank by the combined use of the main elastic body and the sub elastic body is equal to or lower than a predetermined resonance frequency. The washing machine as described in.