This invention relates to a drum type washing machine including a rotating tub inclined rearwardly downward.
FIG. 17 illustrates one of conventional drum type washing machines. The illustrated washing machine comprises an outer cabinet 201 and a water tub 202 elastically supported by a plurality of suspension mechanisms 203 in the cabinet. A rotating tub 204 is rotatably mounted in the water tub 202. A bearing housing 206 is mounted on the rear of the water tub 202. The rotating tub 204 has a rotational shaft 205 supported on a bearing 207 housed in the bearing housing 206.
An electric motor 209 is provided below the water tub 202. A driven pulley 208 is mounted on the rotational shaft 205 of the rotating tub 204. A driving pulley 210 is mounted on a rotational shaft 209a of the motor 209. A transmission belt 212 extends between the pulleys 208 and 210. The driven pulley 208, the driving pulley 210 and the transmission belt 212 constitute a belt transmission mechanism 211. In this construction, torque developed by the motor 209 is transmitted via the belt transmission mechanism 211 to the rotating tub 204, whereby the rotating tub is rotated.
Household drum type washing machines are usually installed on a floor. A user bends his or her knees to put and take laundry into and out of the rotating tub. The prior art has proposed a drum type washing machine with a rotating tub inclined rearwardly downward so that the interior of the rotating tub can easily be viewed when laundry is put into and taken out of the rotating tub. However, the following problems result from this construction. That is, laundry moves to a deep interior of the rotating tub when it is rotated. As a result, an amount of vibration or oscillation produced during rotation of the rotating tub is increased.
The belt transmission mechanism particularly tends to produce vibration for the reason that the driving pulley slips during high-speed rotation or for other reasons. Accordingly, when the rotating tub is inclined rearwardly downward, the vibration produced by the rotating tub is further increased. Further, the water tub swings upon vibration of the rotating tub. To prevent collision of the water tub against the outer cabinet, a sufficient distance needs to be ensured between the water tub and the cabinet. For this purpose, the size of the cabinet needs to be increased when a large amount of vibration is produced from the rotating tub.
Therefore, an object of the present invention is to provide a drum type washing machine which includes a rotating tub inclined rearwardly downward for improvement in the easiness of access to the rotating tub and can yet reduce an amount of vibration.
The present invention provides a drum type washing machine comprising an outer cabinet including a front further including a front panel having a laundry access opening and a door provided on the front panel to close and open the access opening, the front of the cabinet being inclined at an angle relative to a vertical axis, a water tub provided in the cabinet, a rotating tub provided in the water tub so as to be inclined rearwardly downward so that the inclination angle of the front of the cabinet is smaller than an inclination angle of a front of the rotating tub relative to the vertical axis and an electric motor provided on a rear wall of the water tub for directly driving the rotating tub.
According to the above-described construction, the efficiency in the access to the rotating tub or in putting or taking laundry into and out of the rotating tub can be improved since the rotating tub is inclined rearwardly downward can be restrained. Further, the inclination of the front of the rotating tub can be set so that the laundry is readily put into and taken out of the rotating tub, and the inclination of the front of the cabinet can be set so that an increase in the size of the cabinet is prevented. Additionally, the door can be prevented from being inadvertently closed in the open state. Further, since the rotating tub is directly driven by the motor, an increase in the amount of vibration or noise produced during rotation of the rotating tub due to the provision of the rotating tub inclined rearwardly downward.
The motor is preferably of an outer rotor type. An outer rotor type motor has a smaller axial dimension and develops a higher torque than an inner rotor type motor. Accordingly, an increase in a back-and-forth dimension of the outer cabinet can be limited when the outer rotor type motor is provided on the rear wall of the water tub.
The rotating tub preferably has an axis of rotation inclined in an angular range between 10 and 20 degrees relative to a horizontal axis. Consequently, since the interior of the rotating tub can be viewed widely from the front area to the deep interior, the efficiency in the access to the rotating tub can further be improved.
The outer cabinet preferably has an access opening formed in a front wall thereof. The drum type washing machine further comprises a door for closing and opening the access opening of the cabinet, a door-opening operation detecting element detecting an operation for opening the door and a control element stopping the motor by means of electric braking, the control element stopping the motor when a detecting operation has been carried out by the door-opening operation detecting element. The motor is braked on the basis of any door-opening operation effected by another previously performed operation. Consequently, since the rotating tub is stopped in a short time from the time of an actual opening of the door, the safety can be improved. Particularly when the rotating tub is directly driven by the motor, the motor can be stopped in a shorter time by the electrical braking than by the mechanical braking. This further improves the safety.
The outer cabinet preferably has an access opening formed in a front wall thereof. The drum type washing machine further comprises an operation control element controlling a washing operation, and a switch indicative of execution of the washing operation. The operation control element prohibits the washing operation until the switch is operated when the door has been opened after start of the washing operation. When the door is opened after start of the washing operation, it is not restarted until the switch is operated and execution of the washing operation is instructed. Consequently, an inadvertent rotation of the rotating tub can be prevented and accordingly, the safety can be improved.
The invention also provides a drum type washing machine comprising an outer cabinet, a water tub provided in the cabinet so as to be inclined rearwardly downward, the water tub having a rear wall, a rotating tub provided in the water tub so as to be inclined rearwardly downward, an electric motor provided on the rear wall of the water tub for directly driving the rotating tub, and a dryer provided for drying laundry in the rotating tub and including a blower disposed at a back of the upper rear wall of the water tub in the cabinet. In this construction, the water tub is inclined rearwardly downward and the blower is disposed at the back of an upper rear wall of the water tub in the cabinet. When the water tub is inclined rearwardly downward as well as the rotating tub, a dead space results from the construction at the back of the upper rear wall of the water tub in the cabinet. Since the blower is disposed at the back of the upper rear wall of the water tub, the dead space can effectively be used.
The water tub is preferably inclined rearwardly downward. In this construction, the drum type washing machine further comprises a drain pump for draining the water tub, the drain pump being disposed below a front lower portion of the water tub in the cabinet. When the water tub is inclined rearwardly downward as well as the rotating tub, a dead space results from the construction at the back of the lower rear wall of the water tub in the cabinet. Since the drain pump is disposed at the back of the lower rear wall of the water tub, the dead space can effectively be used.
The front panel of the cabinet has a smaller inclination than the front of the rotating tub relative to a vertical axis. Consequently, the outer cabinet can be prevented from an increase in the back-and-forth dimension thereof.
The front of the rotating tub has an inclination ranging between 5 and 20 degrees and the front of the cabinet has an inclination set so as to be smaller than an inclination of the rotating tub by or above 2 degrees and so as to range between 3 and 15 degrees. Consequently, the outer cabinet can be prevented from an increase in the back-and-forth dimension thereof with an efficiency in the work for putting and taking the laundry into and taking out of the rotating tub.
The front panel of the cabinet preferably includes a portion located lower than the access opening and formed into a vertical face. Consequently, an increase in the back-and-forth dimension of the lower portion of the outer cabinet can particularly be prevented.
The invention further provides a drum type washing machine comprising an outer cabinet having a front including a front panel having a laundry access opening and a door provided on the front panel to close and open the access opening, the front of the cabinet being inclined at an angle relative to a vertical axis, a water tub provided in the cabinet, a rotating tub provided in the water tub so as to be inclined rearwardly downward so that the inclination angle of the front of the cabinet is smaller than an inclination angle of a front of the rotating tub relative to the vertical axis, and an electric motor driving the rotating tub. Since no special parts are required for the air supply port, the construction of the washing machine can be simplified.
The drum type washing machine preferably further comprises bellows connecting laundry access opening and an opening of the water tub and a dryer for drying laundry in the rotating tub, the dryer including a hot air generator for generating hot air. In this construction, the water tub is inclined rearwardly downward and the bellows have an air supply port through which the hot air is supplied from the hot air generator into the rotating tub. Consequently, since no special parts are required for the air supply port, the construction of the washing machine can be simplified.