Suction inlet body and vacuum cleaner

Abstract

To provide a suction port body that comprises a rotary brush normally rotating in a preceding manner and a rotary brush reversely rotating in a following manner and that can achieve both of frisky moving performance and dust removing performance adaptable to a variety of surfaces to be cleaned, and a vacuum cleaner.SOLUTION: A suction port body 16 determines in which direction crossing a rotation center line a plurality of rotary cleaning bodies 28 travel on the basis of the result of detection by a current detection circuit 98. A plurality of electric motors 29 are operated so that an auxiliary force generated in a traveling direction by the normally-rotating rotary cleaning body 28 can be greater than a resistance force generated in a direction opposite to the traveling direction by the reversely-rotating rotary cleaning body 28.SELECTED DRAWING: Figure 11

Description

Technical Field

[0001] Embodiments according to the present invention relate to a suction port body and a vacuum cleaner.

Background Art

[0002] There is known a suction port body including two rotating brushes and two electric motors that independently rotate and drive the two rotating brushes.

[0003] The two rotating brushes have a rotation center line extending in the width direction of the suction port body and are arranged in front of and behind the suction port body. The two rotating brushes sandwich the suction port. When the suction port body moves in the front-rear direction, the leading rotating brush rotates to assist the running of the suction port body, scrapes up dust on the surface to be cleaned backward, and guides it to the suction port, and the trailing rotating brush rotates to resist the running of the suction port body, scrapes up dust on the surface to be cleaned forward, and guides it to the suction port.

[0004] For the convenience of the following description, the rotation of the rotating brush that precedes and assists the running of the suction port body is called the leading forward rotation, and the rotation of the rotating brush that trails and resists the running of the suction port body is called the trailing reverse rotation.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The load on the motor that rotates the rotary brush depends on the rolling resistance between the rotary brush and the surface to be cleaned with which the rotary brush is in contact. In the environment where household vacuum cleaners are generally used, there are a plurality of surfaces to be cleaned with different properties mixed together. Representative examples of a plurality of surfaces to be cleaned with different properties are smooth surfaces to be cleaned with low rolling resistance such as wooden floors and flooring, and surfaces to be cleaned with high rolling resistance such as carpets. In addition, a surface to be cleaned such as a carpet has a fabric grain flow called the grain direction and the reverse grain direction. The rolling resistance between the grain direction of the carpet and the rotary brush and the rolling resistance between the reverse grain direction of the carpet and the rotary brush may also be different. That is, generally, the rolling resistance between the rotary brush and the surface to be cleaned with which the rotary brush is in contact in the environment where household vacuum cleaners are used varies greatly depending on the properties of the surface to be cleaned.

[0007] And the conventional suction inlet body includes a rotary brush that rotates forward in the forward direction and a rotary brush that rotates backward in the reverse direction. In such a conventional suction inlet body, for example, when the contact state between the rotary brush and the surface to be cleaned is set with emphasis on a smooth surface to be cleaned such as a wooden floor or flooring, on a surface to be cleaned with high rolling resistance such as a carpet, stop control for avoiding overloading of the motor, that is, safety control, may be frequently executed. In addition, in a suction inlet body in which a plurality of rotary brushes are rotationally driven by a single motor, the load borne by the single motor increases. This increase in load enhances the possibility that safety control for avoiding overloading is executed.

[0008] Also, in the conventional suction inlet body, when the contact state between the rotary brush and the surface to be cleaned is set with emphasis on a surface to be cleaned with high rolling resistance such as a carpet, the contact between the rotary brush and a smooth surface to be cleaned such as a wooden floor or flooring becomes insufficient, and the dust collection performance deteriorates. Furthermore, the magnitude relationship between the propulsive force acting on the surface to be cleaned from the rotary brush that rotates forward in the forward direction and the propulsive force acting on the surface to be cleaned from the rotary brush that rotates backward in the reverse direction greatly affects the comfort of the operation of the suction inlet body. For example, when these propulsive forces are balanced, these propulsive forces cancel each other out and do not contribute to either the forward operation or the backward operation of the suction inlet body.

[0009] Therefore, an object of the present invention is to propose a suction port body and a vacuum cleaner that include a rotation brush that rotates forward in the advancing direction and a rotation brush that rotates backward in the trailing direction, and that can achieve both smooth running performance and dust collection performance corresponding to various surfaces to be cleaned.

Means for Solving the Problems

[0010] The suction port body according to an embodiment of the present invention for solving the above problems includes a plurality of rotary cleaning bodies having parallel rotation center lines, a plurality of electric motors that generate a rotational driving force for the plurality of rotary cleaning bodies, a current detection circuit that individually detects the current flowing through each of the electric motors, and a control unit that controls the operation of the plurality of electric motors. The control unit determines, based on the detection result of the current detection circuit, in which direction any of the plurality of rotary cleaning bodies is advancing that intersects the rotation center line, and operates at least one of the electric motors so that the rotary cleaning body that precedes in the advancing direction rotates in the forward rotation direction to assist the advancement, and operates at least one other electric motor so that at least one of the rotary cleaning bodies that chases the preceding rotary cleaning body rotates in the reverse rotation direction, and operates the plurality of electric motors so that the assisting force generated by the rotary cleaning body rotating forward in the advancing direction is greater than the resistance force generated by the rotary cleaning body rotating backward in the opposite direction of the advancing direction. Detect the change in the traveling direction and determine in which direction the plurality of rotary cleaning bodies are traveling that intersects the rotation center line based on the difference in the current values flowing through at least two of the electric motors that separately rotationally drive at least two of the rotary cleaning bodies having different rotation directions, or based on the difference in the change in the current values flowing through at least two of the electric motors that separately drive at least two of the rotary cleaning bodies having different rotation directions 。

[0011] Further, a vacuum cleaner according to an embodiment of the present invention includes a cleaner main body, an electric blower that is housed in the cleaner main body and generates a negative pressure, and the suction port body that is fluidly connected to the electric blower.

[0012] Furthermore, the vacuum cleaner according to an embodiment of the present invention includes a plurality of rotary cleaning members having parallel rotation center lines, a plurality of electric motors that generate a rotational driving force for the plurality of rotary cleaning members, a current detection circuit that individually detects the current flowing through each of the electric motors, and a control unit that controls the operation of the plurality of electric motors. The control unit determines, based on the detection result of the current detection circuit, in which direction any of the plurality of rotary cleaning members is advancing across the rotation center line, operates at least one of the electric motors so that the rotary cleaning member preceding in the advancing direction rotates in the forward rotation direction to assist the advancement, operates at least one other of the electric motors so that at least one of the rotary cleaning members that follows the preceding rotary cleaning member rotates in the reverse rotation direction, and operates the plurality of electric motors so that the assisting force generated in the advancing direction by the rotary cleaning member rotating in the forward rotation direction is greater than the resistance force generated in the direction opposite to the advancing direction by the rotary cleaning member rotating in the reverse rotation direction. Detect the change in the traveling direction and determine in which direction the plurality of rotary cleaning bodies are traveling that intersects the rotation center line based on the difference in the current values flowing through at least two of the electric motors that separately rotationally drive at least two of the rotary cleaning bodies having different rotation directions, or based on the difference in the change in the current values flowing through at least two of the electric motors that separately drive at least two of the rotary cleaning bodies having different rotation directions 。

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0014] Embodiments of the suction port body and the vacuum cleaner according to the present invention will be described with reference to FIGS. 1 to 12.

[0015] FIG. 1 is a perspective view of a vacuum cleaner according to an embodiment of the present invention.

[0016] As shown in FIG. 1, the vacuum cleaner 1 according to the present embodiment is, for example, a stick type. The vacuum cleaner 1 includes a cleaner body 12 having a handle 11 and capable of being held and operated, a secondary battery 13 detachably attached to the cleaner body 12, an extension pipe 15 connected to the cleaner body 12, and a suction port body 16 connected to the extension pipe 15.

[0017] The vacuum cleaner 1 may be a canister type, an upright type, or a handy type. The vacuum cleaner 1 may be a cordless type powered by the secondary battery 13, or may be a wired type that obtains power from a commercial AC power supply via a power cord.

[0018] The cleaner body 12 includes a main body case 17 having a handle 11, an electric blower 18 housed in the main body case 17 and generating a suction negative pressure, a dust separation and collection unit 19 detachably provided on the main body case 17, and a main body control unit 21 mainly controlling the electric blower 18.

[0019] The vacuum cleaner main body 12 drives the electric blower 18 with the power stored in the secondary battery 13. The negative pressure generated by driving the electric blower 18 acts on the suction port body 16 via the dust separation and collection unit 19 and the extension pipe 15. The electric vacuum cleaner 1 sucks in air containing dust (hereinafter referred to as "dust-containing air") from the floor surface through the suction port body 16 and the extension pipe 15, separates the dust from the dust-containing air, collects and accumulates the separated dust, and exhausts the separated air.

[0020] The main body case 17 includes a cylindrical front half portion 17a arranged on the extension line of the extension pipe 15 in a side view, and a rear half portion 17b that bends from the front half portion 17a and gradually separates from the extension line of the extension pipe 15. Above the front half portion 17a of the main body case 17, a dust separation and collection unit 19 is provided. The rear half portion 17b of the main body case 17 extends rearward in a state where the suction port body 16 is placed on the floor (Figure 2).

[0021] The front portion of the main body case 17 has a main body connection port 23.

[0022] The main body connection port 23 is a detachable joint for the extension pipe 15. The main body connection port 23 protrudes forward from the cylindrical front half portion 17a of the main body case 17. The main body connection port 23 is a fluid inlet of the vacuum cleaner main body 12 and fluidly connects the extension pipe 15 and the dust separation and collection unit 19. By removing the extension pipe 15 from the vacuum cleaner main body 12, the main body connection port 23 also functions as a suction port when using the vacuum cleaner main body 12 alone.

[0023] The handle 11 is integrally provided on the main body case 17. The handle 11 is a part that the user grips by hand in order to clean the floor with the electric vacuum cleaner 1. The handle 11 arches from near the rear end portion of the dust separation and collection unit 19 to the rear end portion of the main body case 17. Also, the handle 11 is arranged to intersect with the extension line of the center line of the extension pipe 15.

[0024] Near the handle 11, an input unit 26 is provided within the range where the user holding the handle 11 can move their fingers.

[0025] The input unit 26 includes an operation start switch 26a that receives an operation start operation of the electric blower 18, an operation stop switch 26b that receives an operation stop operation of the electric blower 18, and a brush switch 26c that receives a start operation and a stop operation of power supply to the suction port body 16. The operation start switch 26a and the operation stop switch 26b are electrically connected to the main body control unit 21. The user of the vacuum cleaner 1 can selectively select the operation mode of the electric blower 18 by operating the input unit 26. The operation start switch 26a also functions as a operation mode changeover switch during the operation of the electric blower 18. In this case, the main body control unit 21 switches the operation mode in the order of strong → medium → weak → strong → medium → weak →... each time it receives an operation signal from the operation start switch 26a. Note that the input unit 26 may alternatively include a strong operation switch (not shown), a medium operation switch (not shown), and a weak operation switch (not shown) individually instead of the operation start switch 26a.

[0026] The dust separation and collection unit 19 is disposed on the upper surface side of the cleaner main body 12 and can be attached to and detached from the cleaner main body 12. The dust separation and collection unit 19 separates dust from the dust-containing air flowing into the cleaner main body 12, collects and accumulates it, and at the same time sends the clean air from which the dust has been removed to the electric blower 18. The dust separation and collection unit 19 may be a centrifugal separation method that centrifugally separates dust and air by utilizing the difference in mass between the dust and the air sucked by the vacuum cleaner 1, or a filtration separation method having a filter that filters out dust from the dust-containing air.

[0027] The electric blower 18 sucks air from the dust separation and collection unit 19 to generate a negative pressure (suction negative pressure).

[0028] The main control unit 21 includes a microprocessor and a storage device that stores various arithmetic programs, parameters, etc. executed by the microprocessor. The storage device stores various settings (arguments) related to a plurality of preset operation modes. The plurality of operation modes are associated with the output of the electric blower 18. Different input values (input value of the electric blower 18, target value of the current flowing through the electric blower 18) are set for each operation mode. Each operation mode is associated with an operation input received by the input unit 26. The main control unit 21 selectively selects an arbitrary operation mode corresponding to the operation input to the input unit 26 from among the plurality of preset operation modes. Further, the main control unit 21 reads the setting of the selected operation mode from the storage unit and operates the electric blower 18 according to the setting of the read operation mode.

[0029] The secondary battery 13 is also called a storage battery, a rechargeable battery, and a recharge battery. The secondary battery 13 stores the electric power consumed by the electric blower 18 and the main control unit 21. The secondary battery 13 may be fixed to the main body case 17 or may be detachable from the main body case 17. In other words, the vacuum cleaner 1 may or may not be able to appropriately replace a plurality of secondary batteries 13 for use. When the charge rate of the secondary battery 13 detachably attached to the vacuum cleaner 1 decreases, the operation of the vacuum cleaner 1 can be continued by replacing this secondary battery 13 with a fully charged secondary battery 13.

[0030] The extension pipe 15 and the suction port body 16 suck up the dust on the floor together with the air by the negative pressure acting from the electric blower 18 and guide it to the cleaner main body 12.

[0031] The extension pipe 15 is fluidly connected to the suction side of the electric blower 18 via the main body connection port 23 of the main body case 17 and the dust separation and collection unit 19. The extension pipe 15 has a length that substantially reaches the floor surface when the user holds the handle 11 of the vacuum cleaner main body 12. A detachable joint structure is provided at one end of the extension pipe 15 for attachment to and detachment from the main body connection port 23 of the vacuum cleaner main body 12. A detachable joint structure is provided at the other end of the extension pipe 15 for attachment to and detachment from the suction port body 16 of the vacuum cleaner main body 12. The extension pipe 15 may or may not be telescopic.

[0032] The suction port body 16 is capable of traveling or sliding freely on the floor surface with its bottom surface facing the floor surface such as a wooden floor or a carpet. The bottom surface of the suction port body 16 has a suction port 27. Further, the suction port body 16 includes a rotatable rotary cleaning body 28 and an electric motor 29 as a drive source for driving the rotary cleaning body 28. A detachable joint structure is provided at one end of the suction port body 16 for attachment to and detachment from the other end of the extension pipe 15. The suction port body 16 is fluidly connected to the suction side of the electric blower 18 via the extension pipe 15. The suction port body 16, the extension pipe 15, and the dust separation and collection unit 19 form a suction air passage from the electric blower 18 to the suction port 27.

[0033] When the operation start switch 26a is operated, the electric vacuum cleaner 1 starts the electric blower 18. For example, when the operation start switch 26a is operated while the electric blower 18 is stopped, the electric vacuum cleaner 1 first starts the electric blower 18 in the strong operation mode. When the operation start switch 26a is operated again, the operation mode of the electric blower 18 is changed to the medium operation mode. When the operation start switch 26a is operated three times, the operation mode of the electric blower 18 is changed to the weak operation mode, and the process is repeated in the same manner hereinafter. The strong operation mode, the medium operation mode, and the weak operation mode are a plurality of preset operation modes. The input value of the electric blower 18 in the strong operation mode is the largest, and the input value of the electric blower 18 in the weak operation mode is the smallest. The started electric blower 18 sucks air from the dust separation and collection unit 19, creating a negative pressure inside the dust separation and collection unit 19.

[0034] The negative pressure inside the dust separation and collection unit 19 acts on the suction port 27 through the main body connection port 23, the extension pipe 15, and the suction port body 16 in sequence. The vacuum cleaner 1 sucks in dust on the surface to be cleaned together with air by the negative pressure acting on the suction port 27 to clean the surface to be cleaned. The dust separation and collection unit 19 separates dust from the dust-containing air sucked into the vacuum cleaner 1 and accumulates it, while sending the air separated from the dust-containing air to the electric blower 18. The electric blower 18 exhausts the air sucked from the dust separation and collection unit 19 to the outside of the cleaner main body 12.

[0035] Next, the suction port body 16 will be described in detail.

[0036] FIG. 2 is a perspective view showing the suction port body according to an embodiment of the present invention from the right front.

[0037] As shown in FIG. 2, the suction port body 16 according to the present embodiment includes a substantially rectangular parallelepiped suction port main body 31 and a connection pipe 32 provided at the rear of the suction port main body 31.

[0038] Note that the front-back, left-right, and up-down directions of the suction port body 16 are described based on the user of the vacuum cleaner 1. The direction of the solid arrow X in FIG. 2 is the front or forward direction of the suction port body 16, and the opposite direction is the rear or backward direction. Also, the direction of the solid arrow Y in FIG. 2 is the left side of the suction port body 16, and the opposite direction is the right side. Further, the direction of the solid arrow Z in FIG. 2 is the upper side of the suction port body 16, and the opposite direction is the lower side.

[0039] The shape of the suction port main body 31 in plan view is a rectangular shape having a short side in the front-back direction and a long side in the left-right direction. That is, the dimension of the suction port main body 31 in the left-right direction, that is, the width dimension, is larger than the dimension of the suction port main body 31 in the front-back direction, that is, the depth dimension. The suction port main body 31 includes a lower case 35 and an upper case 36 covering the lower case 35.

[0040] The connecting pipe 32 is provided at the rear part of the suction port main body 31 and approximately at the center in the width direction. The connecting pipe 32 is a so-called Universal joint. The connecting pipe 32 includes a rotary connecting pipe 38 that can rotate with respect to the suction port main body 31, and a swing connecting pipe 39 that can swing with respect to the rotary connecting pipe 38.

[0041] The rotary connecting pipe 38 rotates around a center line (a line segment that coincides with the X-axis or a line segment parallel to the X-axis) extending in the front-rear direction of the suction port body 16. This center line bisects the suction port main body 31 into left and right parts.

[0042] The swing connecting pipe 39 swings around a line segment orthogonal to the rotation center line of the rotary connecting pipe 38, or a line segment parallel to a line segment orthogonal to the rotation center line of the rotary connecting pipe 38. The free end of the swing connecting pipe 39 is a joint that can be detachably attached to the free end of the extension pipe 15.

[0043] Figures 3 and 4 are plan views of the suction port body according to an embodiment of the present invention.

[0044] Figure 5 is a bottom view of the suction port body according to an embodiment of the present invention.

[0045] Figure 6 is a perspective view of the suction port body according to an embodiment of the present invention as viewed from below.

[0046] Figure 7 is a longitudinal sectional view of the suction port body according to an embodiment of the present invention taken along line VII-VII of Figure 3.

[0047] Figure 8 is a longitudinal sectional view of the suction port body according to an embodiment of the present invention taken along line VIII-VIII of Figure 3.

[0048] Note that in Figure 4, the upper case 36 is removed.

[0049] As shown in FIGS. 3 to 7, the suction port body 16 according to the present embodiment includes a suction port main body 31, a plurality of rotary cleaning bodies 28 rotatably supported by the suction port main body 31, a plurality of electric motors 29 as drive sources for generating the rotational driving force of the rotary cleaning bodies 28, a power transmission mechanism 41 for transmitting the driving force from each electric motor 29 to the corresponding rotary cleaning body 28, and a suction port body control unit 42 for controlling the operation of the electric motors 29.

[0050] The suction port main body 31 has a suction port 27 that opens toward the bottom surface 31a, a suction chamber 45 connected to the suction port 27, and a cleaning body chamber 46 that houses the rotary cleaning body 28.

[0051] The suction port main body 31 also includes a transparent wall 47 that partitions a part of the cleaning body chamber 46 and visually covers at least a part of the outer peripheral surface of the rotary cleaning body 28.

[0052] The cleaning body chamber 46 is partitioned outside the suction chamber 45. The cleaning body chamber 46 is open toward the bottom surface 31a of the suction port main body 31.

[0053] The suction chamber 45 is partitioned by a lower case 35, an air passage cover 48 housed inside an upper case 36 and covering a part of the lower case 35, and an air passage narrowing body 49 that narrows the wide suction port 27 in the left - right direction of the suction port main body 31 toward the central portion. In other words, the lower case 35, the air passage cover 48, and the air passage narrowing body 49 cooperate to partition the suction chamber 45.

[0054] The suction port main body 31 includes a plurality of rollers 50 that are grounded on the surface to be cleaned f to support the suction port main body 31. The plurality of rollers 50 are arranged on the bottom surface 31a of the suction port main body 31. The plurality of rollers 50 include rollers 50 arranged at each of the left and right ends of the suction port main body 31 and a roller 50 arranged at the central portion of the rear part of the suction port main body 31.

[0055] A space is partitioned between the lower case 35 and the upper case 36 of the suction port body 31. This space includes a motor chamber 51 for housing the motor 29, a mechanical chamber 52 for housing the power transmission mechanism 41, and a control chamber 53 for housing the suction port control unit 42. These motor chamber 51, mechanical chamber 52, and control chamber 53 may be connected or separated.

[0056] The control chamber 53 is arranged at the center of the front, rear, left, and right of the suction port body 31 in plan view.

[0057] The plurality of rotary cleaning bodies 28 have parallel rotation center lines. In other words, the rotation center lines of the plurality of rotary cleaning bodies 28 extend in the left - right direction of the suction port body 31. The plurality of rotary cleaning bodies 28 include a pair of rotary cleaning bodies 28 that sandwich the suction port 27 from the front and the rear of the suction port 27.

[0058] The motor 29 and the power transmission mechanism 41 are also in a pair and respectively correspond to each rotary cleaning body 28. One motor 29 rotationally drives one rotary cleaning body 28 via one power transmission mechanism 41. The other motor 29 rotationally drives the other rotary cleaning body 28 via the other power transmission mechanism 41.

[0059] The pair of motors 29 includes a motor 29 provided at one end in the width direction of the suction port body 31 and a motor 29 provided at the other end in the width direction of the suction port body 31. It is preferable that these pair of motors 29 are arranged at positions substantially the same distance from the center line that bisects the suction port body 31 left and right. By doing so, the rotation balance of the suction port body 31 around the flexible joint, that is, the connecting pipe 32, becomes uniform and the handling property is improved.

[0060] A pair of power transmission mechanisms 41 includes a power transmission mechanism 41 provided at one end in the width direction of the suction port body 31 and a power transmission mechanism 41 provided at the other end in the width direction of the suction port body 31. It is preferable that these pair of power transmission mechanisms 41 are arranged at positions substantially the same distance away from the center line that bisects the suction port body 31 left and right. By doing so, the rotation balance of the suction port body 31 around the universal joint, that is, the connecting pipe 32, becomes uniform and the handling performance is improved.

[0061] The rotary cleaning body 28 on the front side of the suction port 27 is called the front cleaning body 28F (first rotary cleaning body). The cleaning body chamber 46 that houses the front cleaning body 28F is called the front cleaning body chamber 46F (first rotary cleaning body chamber). The electric motor 29 corresponding to the front cleaning body 28F is called the front electric motor 29F, and the power transmission mechanism 41 corresponding to the front cleaning body 28F is called the front transmission mechanism 41F. The electric motor chamber 51 that houses the front electric motor 29F is called the front electric motor chamber 51F, and the machine chamber 52 that houses the front transmission mechanism 41F is called the front machine chamber 52F.

[0062] The rotary cleaning body 28 on the rear side of the suction port 27 is called the rear cleaning body 28R (second rotary cleaning body). The cleaning body chamber 46 that houses the rear cleaning body 28R is called the rear cleaning body chamber 46R (second rotary cleaning body chamber). The electric motor 29 corresponding to the rear cleaning body 28R is called the rear electric motor 29R, and the power transmission mechanism 41 corresponding to the rear cleaning body 28R is called the rear transmission mechanism 41R. The electric motor chamber 51 that houses the rear electric motor 29R is called the rear electric motor chamber 51R, and the machine chamber 52 that houses the rear transmission mechanism 41R is called the rear machine chamber 52R.

[0063] The front cleaning body chamber 46F, the suction port 27, and the rear cleaning body chamber 46R are arranged in the advancing direction of the suction port body 16. In other words, the front cleaning body 28F, the suction port 27, and the rear cleaning body 28R are arranged in the advancing direction of the suction port body 16. The front cleaning body 28F, the suction port 27, and the rear cleaning body 28R are arranged from the front side to the rear side of the suction port body 16. Further, the front cleaning body 28F, the air passage narrowing body 49, and the rear cleaning body 28R are arranged in the advancing direction of the suction port body 16. The front cleaning body chamber 46F, the suction port 27, and the rear cleaning body chamber 46R have substantially the same width dimension.

[0064] When the suction port body 16 is moving forward, the front cleaning body chamber 46F and the front cleaning body 28F move forward ahead of the rear cleaning body chamber 46R and the rear cleaning body 28R, and the rear cleaning body chamber 46R and the rear cleaning body 28R follow behind the front cleaning body chamber 46F and the front cleaning body 28F and move forward. When the suction port body 16 is moving backward, the rear cleaning body chamber 46R and the rear cleaning body 28R move backward ahead of the front cleaning body chamber 46F and the front cleaning body 28F, and the front cleaning body chamber 46F and the front cleaning body 28F follow behind the rear cleaning body chamber 46R and the rear cleaning body 28R and move backward.

[0065] The electric motor 29 rotates the rotary cleaning body 28 in the direction of sweeping and collecting dust on the surface to be cleaned f into the suction port 27 with the suction port main body 31 disposed on the surface to be cleaned f. That is, the front electric motor 29F rotates the front cleaning body 28F in the rotation direction Rf that assists the forward movement of the suction port body 16, and the rear electric motor 29R rotates the rear cleaning body 28R in the rotation direction Rr that assists the backward movement of the suction port body 16.

[0066] Hereinafter, when the suction port body 16 is moving forward, the rotation of the front cleaning body 28F in the rotation direction Rf that assists the forward movement is called the forward sequential rotation, and the rotation of the rear cleaning body 28R in the rotation direction Rr is called the backward reverse rotation. When the suction port body 16 is moving backward, the rotation of the rear cleaning body 28R in the rotation direction Rr that assists the backward movement is also the forward sequential rotation, and the rotation of the front cleaning body 28F in the rotation direction Rf is also the backward reverse rotation.

[0067] Also, the propulsive force Ff acting on the surface to be cleaned f from the rotary cleaning body 28 that rotates in the forward sequential rotation is called the assisting force, and the propulsive force Fr acting on the surface to be cleaned f from the rotary cleaning body 28 that rotates in the backward reverse rotation is called the resistance force.

[0068] The assisting force acts toward the front of the suction port body 16 if the suction port body 16 is moving forward, and acts toward the rear of the suction port body 16 if the suction port body 16 is moving backward. The resistance force acts toward the rear of the suction port body 16 if the suction port body 16 is moving forward, and acts toward the front of the suction port body 16 if the suction port body 16 is moving backward.

[0069] The permeable wall 47 partitions a part of each cleaning body chamber 46 and visually covers at least a part of the outer peripheral surface of each rotating cleaning body 28. Therefore, the suction port body 31 has at least one window portion 55 blocked by the permeable wall 47. This window portion 55 may be provided in each cleaning body chamber 46 or may be provided across a plurality of adjacent cleaning body chambers 46. The window portion 55 according to the present embodiment includes a front cleaning body window 55F provided in the upper case 36 so as to be able to visually observe the front cleaning body 28F and a rear cleaning body window 55R provided in the lower case 35 so as to be able to visually observe the rear cleaning body 28R.

[0070] The front cleaning body window 55F is located above the front cleaning body 28F and is open over the entire length of the front cleaning body 28F.

[0071] The rear cleaning body window 55R is located above the rear cleaning body 28R and is divided and open at two positions on the left and right of the rear cleaning body 28R in order to avoid the suction chamber 45 leading to the connecting pipe 32 through the upper part of the rear cleaning body chamber 46R. That is, the rear cleaning body window 55R includes a plurality of divided windows 55RL, 55RR divided in the direction along the rotation center line of the rear cleaning body 28R.

[0072] And the permeable wall 47 includes a first permeable wall 47A that blocks the front cleaning body window 55F and visually covers the front cleaning body window 55F, and a second permeable wall 47B that blocks the rear cleaning body window 55R and visually covers the rear cleaning body window 55R. Further, the second permeable wall 47B may be divided in the direction along the rotation center line of the rear cleaning body 28R. That is, the second permeable wall 47B may include a plurality of divided permeable walls 47BL, 47BR divided in the direction along the rotation center line of the rear cleaning body 28R. In other words, at least one permeable wall 47 includes a plurality of divided permeable walls 47BL, 47BR divided in the direction along the rotation center line of at least one rotating cleaning body 28.

[0073] The first permeable wall 47A is fixed to the upper case 36. The first permeable wall 47A extends from the top portion 28Fa, which is the portion of the pre-cleaning body 28F that is farthest from the surface f to be cleaned, along the rotation direction Rf of the pre-cleaning body 28F in a state where the suction port body 31 is disposed on the surface f to be cleaned. The second permeable wall 47B is fixed to the lower case 35. The second permeable wall 47B extends from the top portion 28Ra, which is the portion of the post-cleaning body 28R that is farthest from the surface f to be cleaned, along the rotation direction Rr of the post-cleaning body 28R in a state where the suction port body 31 is disposed on the surface f to be cleaned. In other words, the permeable wall 47 extends along the rotation direction of the rotary cleaning body 28 from the portions 28Fa and 28Ra, which are the portions of the corresponding rotary cleaning body 28 that are farthest from the surface f to be cleaned, in a state where the suction port body 31 is disposed on the surface f to be cleaned.

[0074] The first permeable wall 47A covers the upper part of the pre-cleaning body 28F and defines the front opening edge (the opening edge farthest from the suction port 27) of the pre-cleaning body chamber 46F. The first permeable wall 47A is a permeable member 56 that also serves as a part of the outer shell of the suction port body 31. That is, the lower case 35, the upper case 36, and the permeable member 56 cooperate to form the outer shell of the suction port body 31. The permeable member 56 may be integrated with the second permeable wall 47B in addition to the first permeable wall 47A. In other words, the permeable member 56 may be all or part of the plurality of permeable walls 47.

[0075] The permeable member 56 covers the upper case 36 and straddles the upper part of the post-cleaning body chamber 46R, and is connected to the lower case 35 behind the post-cleaning body window 55R. That is, the permeable member 56 cooperates with the second permeable wall 47B to double-cover the post-cleaning body window 55R. The permeable member 56 is a molded product or a formed product of a transparent or translucent resin.

[0076] The suction port 27 is disposed between the pre-cleaning body chamber 46F and the post-cleaning body chamber 46R. In other words, the suction port 27 is disposed between the pre-cleaning body 28F and the post-cleaning body 28R. The suction port 27 faces the surface f to be cleaned without being blocked by the pre-cleaning body 28F and the post-cleaning body 28R, and directly views the surface f to be cleaned.

[0077] The suction chamber 45 curves rearward of the suction port body 31 along the lower case 35 so as to cover the rear cleaning body chamber 46R, and is connected to the connecting pipe 32. A relay pipe 57 is provided between the suction chamber 45 and the connecting pipe 32. The relay pipe 57 serves as a base for supporting the connecting pipe 32. The relay pipe 57 is integrally formed with the air passage cover 48.

[0078] The front cleaning body chamber 46F is partitioned by the upper case 36, the lower case 35, the first permeable wall 47A of the permeable wall 47, and the air passage narrowing body 49. In other words, the upper case 36, the lower case 35, the first permeable wall 47A of the permeable wall 47, and the air passage narrowing body 49 cooperate to partition the front cleaning body chamber 46F. The front cleaning body chamber 46F is visible from the outside of the suction port body 31 through the first permeable wall 47A.

[0079] The rear cleaning body chamber 46R is partitioned by the lower case 35, the second permeable wall 47B of the permeable wall 47, and the air passage narrowing body 49. In other words, the lower case 35, the second permeable wall 47B of the permeable wall 47, and the air passage narrowing body 49 cooperate to partition the rear cleaning body chamber 46R. The rear cleaning body chamber 46R is visible from the outside of the suction port body 31 through the second permeable wall 47B.

[0080] The machine chamber 52 is partitioned at each of the left and right ends of the suction port body 31, in the non-existent parts of the front cleaning body chamber 46F, the suction port 27, and the rear cleaning body chamber 46R. The machine chamber 52 houses the shaft ends of the front cleaning body 28F and the rear cleaning body 28R. A roller 50 is provided at the bottom of the machine chamber 52.

[0081] The front-use machine chamber 52F is partitioned at the left end of the suction port body 31, in the non-existent parts of the front cleaning body chamber 46F, the suction port 27, and the rear cleaning body chamber 46R. The front-use machine chamber 52F houses the shaft ends of the front cleaning body 28F and the rear cleaning body 28R.

[0082] The rear working machine room 52R is at the right end of the suction port body 31 and is partitioned into a part where the front cleaning body chamber 46F, the suction port 27, and the rear cleaning body chamber 46R do not exist. The rear working machine room 52R houses the shaft ends of the front cleaning body 28F and the rear cleaning body 28R.

[0083] The motor room 51 overlaps the front cleaning body chamber 46F, the suction port 27, and the rear cleaning body chamber 46R in plan view and is arranged between the control room 53 and the machine room 52. In side view, the rotation center lines of the front cleaning body 28F, the rear cleaning body 28R, and the motor 29 are located at the respective vertices of a triangle. The motor room 51 houses the cylindrical motor 29 as close as possible to the front cleaning body chamber 46F and the rear cleaning body chamber 46R. That is, the bottom of the motor 29 is arranged below the top 28Fa of the front cleaning body 28F and the top 28Ra of the rear cleaning body 28R. In other words, the motor 29 has a part closer to the cleaning surface f than the line segment connecting the part 28Fa farthest from the cleaning surface f of the front cleaning body 28F and the part 28Ra farthest from the cleaning surface f of the rear cleaning body 28R, and is arranged between the front cleaning body 28F and the rear cleaning body 28R. Such an arrangement of the motor 29 and the configuration of the motor room 51 keep the height of the suction port body 31 lower than the sum of the height (diameter) of the rotating cleaning body 28 and the height (diameter) of the motor 29 even when the motor 29 is arranged above the rotating cleaning body 28.

[0084] The front motor room 51F is arranged on the left side of the suction port body 31 and is provided in the front working machine room 52F.

[0085] The rear motor room 51R is arranged on the right side of the suction port body 31 and is provided in the rear working machine room 52R.

[0086] If the front motor room 51F and the front working machine room 52F are provided together, the front motor room 51F and the front working machine room 52F may be arranged on the right side of the suction port body 31. In this case, the front transmission mechanism 41F is also arranged on the right side of the suction port body 31. The rear motor room 51R, the rear working machine room 52R, and the rear transmission mechanism 41R are arranged on the left side of the suction port body 31.

[0087] The rotation center line of the rotary cleaning body 28 is directed in the width direction of the suction port body 31. The rotary cleaning body 28 has brush hairs 59 extending radially. The brush hairs 59 are a plurality of brush filaments extending in the longitudinal direction of the rotary cleaning body 28 and arranged in the circumferential direction of the rotary cleaning body 28.

[0088] Most of the rotary cleaning body 28 may be accommodated in the cleaning body chamber 46, or most of the side surface portion of the rotary cleaning body 28 may be exposed outside the cleaning body chamber 46. It is preferable that the exposed portion of the rotary cleaning body 28 is a part of the front surface and a part of the back surface of the suction port body 31.

[0089] The electric motor 29 is provided with an output shaft 29a protruding into the machine chamber 52. The rotation center line of the output shaft 29a is substantially parallel to the rotation center line of the rotary cleaning body 28.

[0090] The power transmission mechanism 41 includes a driving gear 61 fixed to the output shaft 29a of the electric motor 29, a driven gear 62 provided on the rotary cleaning body 28, and an endless belt 63 wound around the driving gear 61 and the driven gear 62 to transmit driving force from the electric motor 29 to the rotary cleaning body 28.

[0091] Note that the electric motor 29 and the power transmission mechanism 41 may be accommodated inside the rotary cleaning body 28, that is, inside the cylindrical shaft portion corresponding to the base of the brush hairs 59.

[0092] The suction port control unit 42 operates the electric motor 29 with the electric power supplied from the cleaner main body 12 via the extension pipe 15.

[0093] The air passage constriction body 49 includes a partition wall 65 that partitions and separates the suction chamber 45 and the cleaning body chamber 46 and defines a part of the edge of the suction port 27, and a dust removal protrusion 66 that protrudes from the edge of the partition wall 65 and contacts the rotary cleaning body 28.

[0094] The partition wall 65 that divides the suction chamber 45 and the front cleaning body chamber 46F is called the front partition wall 65F. The front partition wall 65F defines the front edge of the suction port 27. The dust removal protrusion 66 that protrudes from the edge of the front partition wall 65F and contacts the front cleaning body 28F is called the front protrusion 66F.

[0095] The partition wall 65 that divides the suction chamber 45 and the rear cleaning body chamber 46R is called the rear partition wall 65R. The rear partition wall 65R defines the rear edge of the suction port 27. The dust removal protrusion 66 that protrudes from the edge of the rear partition wall 65R and contacts the rear cleaning body 28R is called the rear protrusion 66R.

[0096] A part of the inner surface of the suction chamber 45 (here, the rear inner surface of the suction chamber 45, the first remaining part of the inner surface of the suction chamber 45) faces the front partition wall 65F and has a curved surface 68 in an arc shape that bulges toward the front partition wall 65F. The curved surface 68 includes the inner surface of the rear partition wall 65R and the surface of the lower case 35 that is continuous with the inner surface of the rear partition wall 65R. The lower case 35 has an arc-shaped wall that partitions a part of the rear cleaning body chamber 46R. This wall surrounds the rear cleaning body 28R concentrically with a substantially uniform thickness and is smoothly continuous with the inner surface of the rear partition wall 65R.

[0097] The dust swept up from the surface to be cleaned f by the rotation of the front cleaning body 28F heads toward the curved surface 68 of the suction chamber 45. Then, the curved surface 68 smoothly guides the flying dust to the back side (downstream side) of the suction chamber 45.

[0098] In addition, a part of the inner surface of the suction chamber 45 (here, the inner surface on each of the left and right sides of the suction chamber 45, the second remaining part of the inner surface of the suction chamber 45) is connected to the partition wall 65 and has a funnel-shaped inclined surface 71 that narrows the air passage width toward the back side (downstream side) of the suction chamber 45. The inclined surface 71 is connected to the front partition wall 65F and the rear partition wall 65R. In other words, the inclined surface 71 is bridged between the front partition wall 65F and the rear partition wall 65R. There is a pair of inclined surfaces 71 on the left and right sides of the air passage narrowing body 49. The left and right inclined surfaces 71 are inclined so as to move away from the corresponding end of the air passage narrowing body 49 and to enter the back side of the suction chamber 45 as they approach the center of the air passage narrowing body 49. The left and right inclined surfaces 71 are separated without merging. The gap between the left and right inclined surfaces 71 is connected to the suction chamber 45 on the back side of the inclined surface 71. The inclined surface 71 smoothly guides the air sucked through the suction port 27 that is elongated and spreads in the width direction of the suction port body 16 to the rear side of the suction chamber 45 that is connected to the connecting pipe 32.

[0099] The inclined surface 71 has a step shape including a guide surface 72 facing the partition wall 65 in a vertical cross-sectional view of the suction port main body 31. The guide surface 72 faces the front partition wall 65F. This step-shaped portion may be a single step as shown in FIG. 7, or may be multiple steps. The step shape preferably reaches the entire width of the inclined surface 71. The bottom shape of each step may be flat or may be recessed. The guide surface 72 is preferably parallel to the front partition wall 65F. The guide surface 72 captures dust swept up by the front cleaning body 28F and guides it to the back side of the suction chamber 45. In addition, the guide surface 72 guides the end of the thread-like dust to the back side of the suction chamber 45 so that the middle part of the thread-like dust is sandwiched between the front cleaning body 28F and the surface to be cleaned f, and one or both ends of the thread-like dust float up toward the suction port 27 does not go over the rear partition wall 65R and approach the rear cleaning body 28R side.

[0100] The dust-removing protrusion 66 enters inside the rotation locus of the rotary cleaning body 28. The dust-removing protrusion 66 bounces the brush hairs 59 of the rotary cleaning body 28 as the rotary cleaning body 28 rotates. At this time, the dust-removing protrusion 66 bounces off the filamentous dust that adheres to the rotary cleaning body 28 and attempts to enter the cleaning body chamber 46 from the brush hairs 59, causing it to detach from the rotary cleaning body 28. The filamentous dust that has detached from the rotary cleaning body 28 is easily sucked into the suction port 27. That is, the dust-removing protrusion 66 can prevent the filamentous dust adhering to the rotary cleaning body 28 from entering the cleaning body chamber 46.

[0101] The dust-removing protrusion 66 is preferably provided across the entire width of the partition wall 65. The dust-removing protrusion 66 only needs to be able to deflect the brush hairs 59 of the rotary cleaning body 28. Therefore, the shape of the dust-removing protrusion 66 may be a comb shape as shown in FIGS. 5 and 6, or may be a plate shape with a uniform protruding length across the entire width. Since the rolling resistance of the rotary cleaning body 28 increases when the dust-removing protrusion 66 comes into contact, the shape of the dust-removing protrusion 66 is appropriately set according to the output of the electric motor 29.

[0102] When the ground contact surface of the suction port body 16 is taken as the reference surface, the front protrusion 66F is substantially parallel to the reference surface. The rear protrusion 66R protrudes inclined in a direction away from the reference surface.

[0103] Generally, the user advances the suction port body 16 to enter the suction port body 16 onto the surface f to be cleaned that has not been cleaned. At this time, the filamentous dust on the surface f to be cleaned moves from the front to the rear of the suction port body 16. By making the front protrusion 66F substantially parallel to the reference surface while inclining the rear protrusion 66R in a direction away from the reference surface, it becomes difficult for the filamentous dust to enter both the front cleaning body chamber 46F and the rear cleaning body chamber 46R.

[0104] Also, the rear partition wall 65R has a hole 73 that connects the suction chamber 45 and the rear cleaning body chamber 46R. The hole 73 is arranged within the range sandwiched between the left and right inclined surfaces 71. There may be a plurality of holes 73. The hole 73 discharges the dust that has entered the rear cleaning body chamber 46R into the suction chamber 45 so that the dust does not remain in the rear cleaning body chamber 46R.

[0105] In addition, the dust that has entered the pre-cleaning body chamber 46F is discharged forward of the suction port body 16 as the pre-cleaning body 28F rotates. That is, the dust that has entered the pre-cleaning body chamber 46F has more opportunities to be sucked into the suction port 27 during the forward movement of the suction port body 16 than the dust that has entered the post-cleaning body chamber 46R. Therefore, the front partition wall 65F does not necessarily need to have the holes 73 like the rear partition wall 65R.

[0106] Also, if dust enters the cleaning body chamber 46, the user can visually recognize the dust that has entered the cleaning body chamber 46 through the transparent wall 47. That is, the user can visually recognize whether dust has entered the pre-cleaning body chamber 46F through the first transparent wall 47A, and can visually recognize whether dust has entered the post-cleaning body chamber 46R through the second transparent wall 47B.

[0107] A protruding portion 75 having an acute longitudinal cross-sectional shape facing the post-cleaning body 28R is provided at a part of the opening edge of the post-cleaning body chamber 46R that faces the rear protrusion 66R. The protruding portion 75 is provided at the rear side portion of the opening edge of the post-cleaning body chamber 46R. When the suction port body 16 is used on a soft surface to be cleaned f such as a carpet, the suction port main body 31 sinks into the surface to be cleaned f. In such a case, the protruding portion 75 scrapes the surface to be cleaned f like a bulldozer blade and scrapes out the dust that has entered the carpet.

[0108] The protruding portion 75 preferably extends across the entire width of the post-cleaning body chamber 46R. Further, when the suction port body 16 is used on a hard surface to be cleaned f such as flooring, the protruding portion 75 may protrude below the bottom surface 31a of the suction port main body 31 toward the bottom of the suction port main body 31 within a range where it does not contact the surface to be cleaned f.

[0109] Note that the suction port body 16 may include three or more rotary cleaning bodies 28 including a front cleaning body 28F and a rear cleaning body 28R sandwiching the suction port 27 therebetween. That is, the suction port body 16 may include three or more cleaning body chambers 46 including a front cleaning body chamber 46F and a rear cleaning body chamber 46R partitioned outside the suction chamber 45 and sandwiching the suction port 27 therebetween, and three or more rotary cleaning bodies 28 including the front cleaning body 28F and the rear cleaning body 28R, and being disposed in the respective cleaning body chambers 46. In this case, it is preferable that the same number of cleaning body chambers 46 and rotary cleaning bodies 28 are provided. The electric motor 29, the electric motor chamber 51, the power transmission mechanism 41, and the machine chamber 52 may be provided in the same number as the cleaning body chambers 46 and the rotary cleaning bodies 28, or may be fewer than the cleaning body chambers 46 and the rotary cleaning bodies 28 as long as the plurality of rotary cleaning bodies 28 can be rotationally driven in the same direction. For example, the driving force of one electric motor 29 may be distributed by the power transmission mechanism 41 to rotationally drive the plurality of rotary cleaning bodies 28 in the same direction simultaneously. The electric motor 29, the electric motor chamber 51, the power transmission mechanism 41, and the machine chamber 52 may be more numerous than the cleaning body chambers 46 and the rotary cleaning bodies 28. For example, a plurality of electric motors 29 may cooperate to drive one rotary cleaning body 28.

[0110] Further, the suction port body 16 may include three or more transmission walls 47 including a first transmission wall 47A that visually covers the front cleaning body 28F and a second transmission wall 47B that visually covers the rear cleaning body 28R. In this case, each transmission wall 47 is provided in each cleaning body chamber 46. The transmission member 56 may be all or part of the three or more transmission walls 47.

[0111] FIG. 9 is a partial cross-sectional view of a suction port body according to an embodiment of the present invention.

[0112] As shown in FIGS. 5, 6, and 9, when a plurality of rotary cleaning bodies 28 move in a direction parallel to the rotation center line, that is, in the left-right direction of the suction port body 16, the suction port body 16 according to the present embodiment protrudes from the bottom surface 31a of the suction port main body 31 to move the suction port main body 31 away from the surface f to be cleaned, and includes a resistance reduction mechanism 81 that reduces the rolling resistance of the plurality of rotary cleaning bodies 28.

[0113] The resistance reduction mechanism 81 includes a guide portion 82 that extends in the left - right direction of the suction port main body 31 and is curved convexly upward, a roller 83 that is movable along the guide portion 82, and an induction magnetic force portion 85 that arranges the roller 83 at the central portion of the guide portion 82.

[0114] The guide portion 82 is curved in an upward - convex arch shape.

[0115] When the roller 83 is located at the central portion of the guide portion 82, it is preferably away from the surface f to be cleaned. When the suction port body 16 starts to move in either the left or right direction, the roller 83 contacts the surface f to be cleaned due to inertia force. When the movement of the suction port body 16 continues, the frictional force between the roller 83 and the surface f to be cleaned overcomes the magnetic force of the induction magnetic force portion 85 that attempts to arrange the roller 83 at the central portion of the guide portion, and the roller 83 protrudes from the bottom surface 31a of the suction port main body 31. The protruding amount of the roller 83 is determined by the height difference between the central portion and each end portion of the guide portion 82. When the roller 83 moves to each end portion of the guide portion 82 and protrudes from the bottom surface 31a of the suction port main body 31, the roller 83 contacts the surface f to be cleaned and expands the distance between the suction port main body 31 and the surface f to be cleaned. Then, the contact amount between the rotary cleaning body 28 and the surface f to be cleaned decreases, the rolling resistance decreases, and the ease of movement of the suction port body 16 in the left - right direction increases.

[0116] Note that the roller 83 may be a sled that moves the suction port body 16 away from the surface f to be cleaned and is movable on the surface f to be cleaned.

[0117] The induction magnetic force portion 85 has a fixed magnet 87 installed at the end portion of the guide portion 82 and a moving magnet 88 installed at the base portion of the roller 83. The polarities of the fixed magnet 87 and the moving magnet 88 are set in directions that repel each other. Due to the repulsion between the fixed magnet 87 and the moving magnet 88, the roller 83 is induced to the central portion of the guide portion 82, that is, the neutral position. Therefore, when the roller 83 is not installed on the surface f to be cleaned, it moves to the neutral position by the induction magnetic force portion 85.

[0118] Next, another example of the resistance reduction mechanism 81 of the suction port body 16 according to the present embodiment will be described. In the resistance reduction mechanism 81A described in each example, the same components as those of the resistance reduction mechanism 81 are denoted by the same reference numerals, and redundant descriptions are omitted.

[0119] FIG. 10 is a partial cross-sectional view of another example of the suction port body according to an embodiment of the present invention.

[0120] As shown in FIG. 10, in the suction port body 16 according to the present embodiment, when a plurality of rotary cleaning bodies 28 move in a direction parallel to the rotation center line, that is, in the left-right direction of the suction port body 16, the suction port body 16 protrudes from the bottom surface 31a of the suction port main body 31 and moves away from the suction port main body 31 from the surface f to be cleaned, and is provided with a resistance reduction mechanism 81A for reducing the rolling resistance of the plurality of rotary cleaning bodies 28.

[0121] The resistance reduction mechanism 81A includes a guide portion 82A that extends in the left-right direction of the suction port main body 31 and is curved upwardly convex, a roller 83 that is movable along the guide portion 82A, and a guiding magnetic force portion 85A that arranges the roller 83 at the central portion of the guide portion 82A.

[0122] The guide portion 82A is far from the bottom surface 31a of the suction port main body 31, and has a gently upwardly convex arched central portion and a pair of left and right parallel portions close to the bottom surface 31a of the suction port main body 31.

[0123] The guiding magnetic force portion 85A includes fixed magnets 87A installed at the left end portion of the left parallel portion, both end portions of the central portion, and the right end portion of the right parallel portion in FIG. 9B, and a moving magnet 88 installed at the base portion of the roller 83. The polarities of the fixed magnet 87A and the moving magnet 88 are set in directions opposite to each other. Due to the repulsion between the fixed magnet 87A and the moving magnet 88, the roller 83 is guided to the central portion of the guide portion 82A, that is, the neutral position. Therefore, when the roller 83 is not installed on the surface f to be cleaned, it is moved to the neutral position by the guiding magnetic force portion 85A.

[0124] Note that the suction port body 16 is movable in the front-rear direction along the short side of the suction port main body 31, and is movable left and right along the long side of the suction port main body 31 by the resistance reduction mechanisms 81 and 81A. The travel along the short side of the suction port main body 31 is defined as movement in the front-rear direction (the direction along the solid arrow X in FIG. 2), and the travel along the long side of the suction port main body 31 is defined as movement in the left-right direction (the direction along the solid arrow Y in FIG. 2). Since the suction port body 16 is connected to the extension pipe 15 via the connecting pipe 32 which is a flexible joint, when viewed from the user of the vacuum cleaner 1, it is also possible to travel with the short side of the suction port main body 31 facing the left-right direction of the user and the long side of the suction port main body 31 facing the front-rear direction of the user. In this case, the movement of the suction port main body 31 in the front-rear direction is the movement in the left-right direction as viewed from the user, and the movement of the suction port main body 31 in the left-right direction is the movement in the front-rear direction as viewed from the user. Hereinafter, for the convenience of explanation, the traveling direction of the suction port body 16 will be described in the coordinate system (solid arrows X, Y, Z in FIG. 2) of the suction port body 16.

[0125] FIG. 11 is a control block diagram of the suction port body according to an embodiment of the present invention.

[0126] As shown in FIG. 11, the suction port body 16 according to the present embodiment drives a plurality of electric motors 29 with electric power supplied from the secondary battery 13 mounted on the cleaner main body 12. The suction port body 16 includes a plurality of rotary cleaning bodies 28, a plurality of electric motors 29 provided for each of the rotary cleaning bodies 28 to individually generate a driving force for rotationally driving the rotary cleaning bodies 28, and a suction port body control unit 42 that controls the operation of the plurality of electric motors 29.

[0127] The suction port body control unit 42 is electrically connected to the secondary battery 13 by two electric wires 91 that reach the cleaner main body 12 through the extension pipe 15. One of the two electric wires 91 is the grounded electric wire 92, and the other of the two electric wires 91 is the non-grounded electric wire 93.

[0128] Then, the suction port control unit 42 includes a control power supply generation circuit 95 that steps down the power supplied from the secondary battery 13 and outputs control power, a reference voltage generation circuit 96 that outputs a reference voltage, a plurality of drive circuits 97 provided for each motor 29, a current detection circuit 98 that individually detects the current flowing through the motor 29, and a driving force difference control circuit 99 that collectively controls the currents flowing through the plurality of motors 29 based on the detection results of the current detection circuit 98. Each circuit is individually grounded.

[0129] The reference voltage generation circuit 96 generates a reference voltage for pulse width modulation (PWM) control using the power supplied from the control power supply generation circuit 95 and outputs it to the driving force difference control circuit 99. The reference voltage is a triangular wave. The reference voltage generation circuit 96 outputs a triangular wave by an operational amplifier.

[0130] Each drive circuit 97 includes a switching element that switches the power input to the corresponding motor 29. Each drive circuit 97 individually opens and closes the corresponding switching element by pulse width modulation control.

[0131] Each switching element opens and closes a non-grounded side wire 93 that supplies driving power from the secondary battery 13 to the corresponding motor 29. Each switching element is an element such as a triode AC switch (TRIAC), a reverse blocking three-terminal thyristor (SCR), or a MOSFET (metal-oxide-semiconductor field-effect transistor). Each switching element has a gate connected to the corresponding driving force difference control circuit 99. The switching element changes the input (driving current) of the motor 29 in response to a change in the gate current or gate voltage.

[0132] The current detection circuit 98 outputs a voltage value correlated with the detection result of the current flowing through each motor 29 to the driving force difference control circuit 99. The current detection circuit 98 includes a shunt resistor that converts the current flowing through each motor 29 into a voltage, and an amplifier circuit that amplifies the voltage converted by the shunt resistor and outputs it to the corresponding driving force difference control circuit 99. The amplifier circuit is a so-called differential amplifier circuit including one operational amplifier and four resistors. The current detection circuit 98 may be a plurality of circuits that are separately independent for each motor 29.

[0133] The driving force difference control circuit 99 compares the voltage value output by the current detection circuit 98 with the reference voltage output by the reference voltage generation circuit 96, and switches the switching element of the corresponding drive circuit 97.

[0134] Incidentally, generally, when a microcomputer or a control circuit for controlling the operation of a plurality of motors 29 is provided in the cleaner main body 12, the current flowing through the plurality of motors 29 is detected and synthesized on the side of the suction port body 16, and the detection result of this synthesized current is input to the microcomputer or control circuit on the side of the cleaner main body 12 to control the operation of the plurality of motors 29. Such a control mode is hereinafter referred to as "synthesized current control type".

[0135] Also generally, when a microcomputer or a control circuit for controlling the operation of a plurality of motors 29 is provided in the cleaner main body 12, the current flowing through the plurality of motors 29 is individually detected on the side of the suction port body 16, and the individually detected current is input to the microcomputer or control circuit of the cleaner main body 12 without being synthesized to control the operation of the plurality of motors 29. Such a control mode is hereinafter referred to as "individual control type".

[0136] And the synthesized current control type only needs to include at least two electric wires including a power supply line for supplying power from the cleaner main body 12 to the suction port body 16 and a signal line for transmitting the detection result of the synthesized current from the suction port body 16 to the cleaner main body 12 in order to establish the operation control of the plurality of motors 29.

[0137] On the one hand, for the individual control type, in order to establish the operation control of a plurality of motors 29, at least three electric wires are required, including a power supply line for supplying power from the cleaner main body 12 to the suction port body 16, and a plurality of signal lines for transmitting the detection results of the current flowing through each motor 29 from the suction port body 16 to the cleaner main body 12.

[0138] The combined current control type controls the inputs of a plurality of motors 29 collectively based on the combined current of the plurality of motors 29. That is, in the combined current control type, the microcomputer or control circuit of the cleaner main body 12 cannot individually grasp the load state of each motor 29. Therefore, there is a risk that the input of each motor 29 may become excessive or too small. If the input becomes excessive, the risk of layer short circuit in the motor 29 increases. On the other hand, if the input becomes too small, there is a risk that the rotational speed of the rotary cleaning body 28 decreases and the dust removal ability cannot be exerted.

[0139] Also, in the individual control type, while the microcomputer or control circuit of the cleaner main body 12 can individually grasp the load state of each motor 29, at least three electric wires are required between the cleaner main body 12 including the extension pipe 15 and the suction port body 16. When wiring three or more electric wires between the cleaner main body 12 and the suction port body 16, it leads to an expansion of the tunnel structure for passing the wiring and an increase in the weight of the electric cleaner 1. In other words, the individual control type hinders the miniaturization and weight reduction of the electric cleaner 1.

[0140] Therefore, the suction port body 16 according to the present embodiment is provided for each motor 29, and includes a current detection circuit 98 that individually detects the current flowing through the plurality of motors 29, and a driving force difference control circuit 99 that individually restricts the current flowing through the plurality of motors 29 based on the detection result of the current detection circuit 98. When at least one of the plurality of motors 29 is in an overload state, the current detection circuit 98 detects the motor 29 in the overload state, and the driving force difference control circuit 99 switches the switching element of the drive circuit 97 corresponding to the motor 29 in the overload state to restrict the current flowing through the motor 29 in the overload state. That is, the suction port body control unit 42 detects the current value flowing through each motor 29 by the current detection circuit 98, and when this current value becomes excessive, the driving force difference control circuit 99 restricts the current flowing through the motor 29 in the overload state. By doing so, the suction port body control unit 42 prevents layer short circuits from occurring in the motor 29 in the overload state while continuing the operation of the other motors 29 in the non-overload state.

[0141] Furthermore, the driving force difference control circuit 99 operates at least one motor 29 so that the rotary cleaning body 28 that precedes in the traveling direction rotates in the forward rotation direction to assist the traveling, and operates at least one other motor 29 so that at least one rotary cleaning body 28 that pursues the preceding rotary cleaning body 28 rotates in the reverse rotation direction.

[0142] In the present embodiment, when the suction port body 16 is moving forward, the driving force difference control circuit 99 drives and controls the front motor 29F so that the front cleaning body 28F rotates forward in the leading direction, and drives and controls the rear motor 29R so that the rear cleaning body 28R rotates reversely in the trailing direction. When the suction port body 16 is moving backward, the driving force difference control circuit 99 drives and controls the rear motor 29R so that the rear cleaning body 28R rotates forward in the leading direction, and drives and controls the front motor 29F so that the front cleaning body 28F rotates reversely in the trailing direction.

[0143] Further, the driving force difference control circuit 99 determines in which direction the suction port body 16 is moving, forward or backward, based on the detection result of the current detection circuit 98. In other words, the driving force difference control circuit 99 determines in which direction a plurality of rotary cleaning bodies 28 are moving in a direction intersecting their rotation center lines based on the detection result of the current detection circuit 98.

[0144] Note that the suction port body control unit 42 may be provided in the cleaner main body 12. That is, the control power supply generation circuit 95, the reference voltage generation circuit 96, the drive circuit 97, the current detection circuit 98, and the driving force difference control circuit 99 of the suction port body control unit 42 may be provided in the cleaner main body 12. Further, the control power supply generation circuit 95, the reference voltage generation circuit 96, the drive circuit 97, the current detection circuit 98, and the driving force difference control circuit 99 may be distributed and arranged in the cleaner main body 12 and the suction port body 16.

[0145] FIG. 12 is a graph showing an example of currents flowing through a plurality of electric motors of the suction port body according to an embodiment of the present invention.

[0146] FIG. 12 shows the time changes of the forward drive current value IF flowing through the front electric motor 29F, the rear drive current value IR flowing through the rear electric motor 29R, and the acceleration A in the front-rear direction of the suction port body 16.

[0147] Incidentally, the suction port body 16 travels or slides on the surface f to be cleaned by a force acting through an extension pipe 15 that extends obliquely upward to the rear (extends obliquely downward to the front as viewed from the user). The extension pipe 15 is connected to the suction port body 16 via a connecting pipe 32 that is a universal joint. When the suction port body 16 moves forward, a force that pushes forward and presses against the surface f to be cleaned acts on the suction port body 16 from the extension pipe 15. When the suction port body 16 moves backward, a force that pulls backward and separates from the surface f to be cleaned acts on the suction port body 16 from the extension pipe 15. That is, the suction port body 16 includes a connecting pipe 32 as a joint part that receives a force for advancing the plurality of rotary cleaning bodies 28 while applying a load to the surface f to be cleaned and receives a force for retracting the plurality of rotary cleaning bodies 28 while removing the load from the surface f to be cleaned.

[0148] Therefore, as shown in FIG. 12, when the suction port body 16 is moving forward, the rotational load acting on the electric motor 29 increases, and the forward drive current value IF and the backward drive current value IR increase. Also, when the suction port body 16 is moving backward, the rotational load acting on the electric motor 29 decreases, and the forward drive current value IF and the backward drive current value IR decrease.

[0149] Based on such a relationship, the driving force difference control circuit 99 determines whether the suction port body 16 is moving in the forward or backward direction.

[0150] Specifically, the driving force difference control circuit 99 detects a change in the traveling direction of the suction port body 16 based on the difference in the current values flowing through at least two electric motors 29 that separately rotationally drive at least two rotary cleaning bodies 28 having different rotational directions, and determines in which direction the plurality of rotary cleaning bodies 28 cross the rotation center line. That is, the driving force difference control circuit 99 detects a change in the traveling direction of the suction port body 16 based on the difference between the forward drive current value IF and the backward drive current value IR flowing through the forward motor 29F and the backward motor 29R that separately rotationally drive the front cleaning body 28F and the rear cleaning body 28R, respectively, and determines in which direction the plurality of rotary cleaning bodies 28 cross the rotation center line.

[0151] Further, the driving force difference control circuit 99 may detect a change in the advancing direction of the suction port body 16 based on the difference in the change in the current values flowing through at least two electric motors 29 that separately rotate at least two rotary cleaning members 28 having different rotational directions, and determine in which direction the plurality of rotary cleaning members 28 are advancing that intersects the rotation center line. That is, the driving force difference control circuit 99 may detect a change in the advancing direction of the suction port body 16 based on the difference in the change in the forward driving current value IF and the rear driving current value IR flowing through the front electric motor 29F and the rear electric motor 29R that separately rotate the front cleaning member 28F and the rear cleaning member 28R, respectively, and determine in which direction the plurality of rotary cleaning members 28 are advancing that intersects the rotation center line. In this case, the driving force difference control circuit 99 detects a change in the advancing direction of the suction port body 16 based on at least one of the temporal changes (the slopes in FIG. 12) of the forward driving current value IF and the temporal change (the slope in FIG. 12) of the rear driving current value IR, or based on the difference therebetween.

[0152] Furthermore, the driving force difference control circuit 99 may detect a change in the traveling direction based on the current value flowing through the motor 29 that rotationally drives at least one rotary cleaning member 28 that rotates in the forward direction, or based on a change in the current value flowing through the motor 29 that rotationally drives at least one rotary cleaning member 28 that rotates in the forward direction. The rolling resistance acting on the front cleaning member 28F immediately after the suction port body 16 changes its traveling direction from backward to forward is significantly larger than the rolling resistance acting on the rear cleaning member 28R immediately after the suction port body 16 changes its traveling direction from forward to backward. Immediately after the suction port body 16 changes its direction from backward to forward, the front cleaning member 28F rotates while applying a load to the surface to be cleaned f. In other words, immediately after the rotation direction of the front cleaning member 28F changes from reverse rotation in the rearward direction to forward rotation in the forward direction, the rolling resistance of the front cleaning member 28F increases rapidly. On the other hand, immediately after the suction port body 16 changes its traveling direction from forward to backward, the rear cleaning member 28R rotates while relieving the load from the surface to be cleaned f. In other words, immediately after the rotation direction of the rear cleaning member 28R changes from reverse rotation in the rearward direction to forward rotation in the forward direction, the rolling resistance of the rear cleaning member 28R decreases rapidly. Therefore, by alternately monitoring the forward drive current value IF flowing through the forward motor 29F and the rear drive current value IR flowing through the rear motor 29R, the driving force difference control circuit 99 can detect a change in the current value flowing through the motor 29 that rotationally drives at least one rotary cleaning member 28 that rotates in the forward direction, and can detect a change in the traveling direction of the suction port body 16. Such detection of the change in the traveling direction of the suction port body 16 by alternately monitoring the forward drive current value IF and the rear drive current value IR can also be achieved by detecting a change in the current value flowing through the motor 29 that rotationally drives at least one rotary cleaning member 28 that rotates in the reverse direction in the rearward direction.

[0153] Also, the driving force difference control circuit 99 may detect a change in the traveling direction and determine in which direction any of the plurality of rotary cleaning members 28 that intersect the rotation center line are traveling, based on the length of the duration of the peak current when the forward drive current value IF of the front motor 29F exceeds a predetermined determination current Id. As shown in FIG. 12, the duration of the peak current when the forward drive current value IF exceeds the determination current Id is shorter than the duration of the peak current when the rear drive current value IR exceeds the determination current Id. Here, focus on the current value flowing through the front motor 29F when the traveling direction of the suction port body 16 changes from backward to forward. When the traveling direction of the suction port body 16 changes from backward to forward, the front motor 29F starts to rotate forward first while being strongly pressed against the surface to be cleaned f. At this time, the forward drive current value IF flowing through the front motor 29F instantaneously increases. If the forward movement of the suction port body 16 continues, the rotational load of the front motor 29F decreases, and the forward drive current value IF flowing through the front motor 29F rapidly decreases compared to the rear drive current value IR flowing through the rear motor 29R that rotates backward. By capturing such a change in the current value, the driving force difference control circuit 99 can detect the traveling direction of the suction port body 16.

[0154] Furthermore, during the forward movement of the suction port body 16, the rotational load of the forward cleaning member 28F that rotates forward decreases. Therefore, as shown in FIG. 12, the forward drive current value IF has a tendency to gradually decrease after temporarily increasing. On the other hand, during the forward movement of the suction port body 16, the rotational load of the rear cleaning member 28R that rotates backward is always maintained at a high level. Therefore, as shown in FIG. 12, the rear drive current value IR always maintains a high value during the forward movement of the suction port body 16. Accordingly, by capturing the situation where the state where the rear drive current value IR is high and a high load is maintained on the rear motor 29R, and the state where the forward drive current value IF decreases after temporarily increasing overlap, the driving force difference control circuit 99 can detect the traveling direction of the suction port body 16.

[0155] When the assisting force acting on the surface f to be cleaned from the rotation cleaning body 28 rotating forward in sequence and the resistance force acting on the surface f to be cleaned from the rotation cleaning body 28 rotating backward in reverse balance each other, these propulsive forces cancel each other out and do not contribute to either the forward or backward movement of the suction port body 16. Also, when the resistance force is greater than the assisting force, the resultant force of the propulsive forces acts in the direction opposite to the traveling direction of the suction port body 16, making the user feel resistance.

[0156] Therefore, the driving force difference control circuit 99 of the suction port body 16 according to the present embodiment operates a plurality of electric motors 29 so that the assisting force generated by the rotation cleaning body 28 rotating forward in sequence in the traveling direction of the suction port body 16 is greater than the resistance force generated by the rotation cleaning body 28 rotating backward in reverse in the direction opposite to the traveling direction.

[0157] Note that the assisting force and the resistance force are regardless of differences in the configurations of the respective rotation cleaning bodies 28, for example, differences in the density of the brush bristles or the presence or absence of a silicon blade, but are forces generated as the plurality of rotation cleaning bodies 28 rotate while in contact with the same surface f to be cleaned, specifically, a cleaning surface f having substantially the same coefficient of friction. Therefore, under the condition that the front cleaning body 28F and the rear cleaning body 28R are in contact with the same surface f to be cleaned and no external force acts, the assisting force is always greater than the resistance force.

[0158] Also, the heights of the waves of the pre-drive current value IF and the post-drive current value IR shown in FIG. 12 change according to the magnitude of the rotational load of the corresponding motor 29. The rolling resistance on the cleaning surface f such as a carpet is greater than the rolling resistance on a smooth cleaning surface f such as a wooden floor or flooring. That is, the rotational load of the motor 29 that rotationally drives the rotary cleaning body 28 on the cleaning surface f such as a carpet is greater than the rotational load of the motor 29 that rotationally drives the rotary cleaning body 28 on a smooth cleaning surface f such as a wooden floor or flooring, and the current value flowing through the motor 29 that rotationally drives the rotary cleaning body 28 on the cleaning surface f such as a carpet is greater than the current value flowing through the motor 29 that rotationally drives the rotary cleaning body 28 on a smooth cleaning surface f such as a wooden floor or flooring. Therefore, the driving force difference control circuit 99 estimates the rolling resistance due to the friction of the cleaning surface f in contact with the rotary cleaning body 28 rotationally driven by the motor 29 based on the current value flowing through at least one of the plurality of motors 29, the change in the current value, or the magnitude of the peak current when the current value exceeds a predetermined second determination current.

[0159] Then, when the estimated rolling resistance is greater than a predetermined rolling resistance, for example, when the rotary cleaning body 28 is rotating on a carpet, the driving force difference control circuit 99 sends the first driving power to the plurality of motors 29. Also, when the estimated rolling resistance is less than or equal to the predetermined rolling resistance, for example, when the rotary cleaning body 28 is rotating on a smooth cleaning surface f such as a wooden floor or flooring, the driving force difference control circuit 99 sends a second driving power smaller than the first driving power to the plurality of motors 29. That is, the driving force difference control circuit 99 estimates the magnitude of the rolling resistance of the cleaning surface f in contact with the rotary cleaning body 28 from the rotational load of the motor 29, and changes the magnitude of the operating output of the motor 29 corresponding to the estimated magnitude of the rolling resistance of the cleaning surface f. By doing so, the suction port body 16 can maximize the dust collection performance with efficient power consumption suitable for the nature of the cleaning surface f. Also, even on a cleaning surface where the rolling resistance of the rotary cleaning body 28 changes between the warp and the weft like a carpet, the suction port body 16 can maximize the dust collection performance with efficient power consumption suitable for the nature of the cleaning surface f in both the case of advancing with respect to the warp and retreating with respect to the weft and the case of retreating with respect to the warp and advancing with respect to the weft.

[0160] The suction inlet body 16 obtains a self-propelling force generated from the difference between the assisting force and the resistance force. Therefore, the smaller the rotational torque of the motor 29 that rotates in the reverse direction later, the easier it is to increase the self-propelling force of the suction inlet body 16. However, the motor 29 that rotates in the reverse direction later plays an important role from the viewpoint of dust removal on the surface f to be cleaned. That is, when the rotational torque of the motor 29 that rotates in the reverse direction later is small, the dust removal performance of the suction inlet body 16 significantly deteriorates. Therefore, there is a trade-off relationship between the self-propelling force of the suction inlet body 16 and the dust removal performance of the suction inlet body 16. Such a problem is solved by adopting a motor 29 with a high rotational torque. However, if the rotational torque of the motor 29 is simply increased too much, there is a risk of bouncing off the dust instead of scraping it together. Therefore, the suction inlet body 16 according to the present embodiment appropriately sets the driving power (first driving power, second driving power) according to the nature of the surface f to be cleaned, thereby achieving both the self-propelling force of the suction inlet body 16, the dust removal performance of the suction inlet body 16, and the prevention of dust bouncing off of the suction inlet body 16.

[0161] Therefore, the ratio of the first driving power (the driving power corresponding to the surface f to be cleaned having a large rolling resistance like a carpet) to the second driving power (the driving power corresponding to the surface f to be cleaned having a small rolling resistance like a wooden floor or a flooring) is set, for example, to 13 to 7. Also, the ratio of the assisting force (propulsion force FF) to the resistance force (propulsion force FR) in the first driving power is set, for example, to 10 to 3, and the ratio of the assisting force (propulsion force FF) to the resistance force (propulsion force FR) in the second driving power is set, for example, to 5 to 2. These driving force setting ratios of the motor 29 preferably achieve both the self-propelling force of the suction inlet body 16, the dust removal performance of the suction inlet body 16, and the prevention of dust bouncing off of the suction inlet body 16.

[0162] Note that the second determination current, unlike the determination current Id, is preferably set to an appropriate value capable of determining the nature of the surface f to be cleaned.

[0163] Furthermore, the driving force difference control circuit 99 may estimate the time interval during which the plurality of rotary cleaning members 28 move back and forth in a direction intersecting the rotation center line based on the generation interval of the peak current in which the current value flowing through at least one of the plurality of electric motors 29 exceeds a predetermined third determination current Id3.

[0164] As shown in FIG. 12, in the section where the current values flowing through the plurality of electric motors 29, that is, the pre-driving current value IF and the post-driving current value IR, exceed the third determination current Id3, it can be seen that the suction port body 16 is moving forward. Note that the third determination current Id3 may be the same as the determination current Id, and it is preferably set to an appropriate value that can distinguish the back-and-forth movement of the plurality of rotary cleaning members 28 on various cleaning surfaces f with different properties.

[0165] Then, when the estimated time interval for the back-and-forth movement is shorter than a predetermined time interval, the driving force difference control circuit 99 sets the difference between the assisting force (propulsion force FF) generated by the forward-rotating rotary cleaning member 28 in the advancing direction of the suction port body 16 and the resistance force (propulsion force FR) generated by the backward-rotating rotary cleaning member 28 in the opposite direction of the advancing direction as the first difference. Also, when the estimated time interval is equal to or longer than the predetermined time interval, the driving force difference control circuit 99 sets the difference between the assisting force and the resistance force as the second difference, which is larger than the first difference. By doing so, when it is estimated that the interval of the back-and-forth time of the forward and backward movement of the suction port body 16, or the cycle of the forward and backward movement of the suction port body 16 is short and the suction port body 16 is moving at high speed, the difference between the assisting force and the resistance force is set to the smaller first difference to prioritize the dust removal force by the backward-rotating rotary cleaning member 28. Also, when it is estimated that the interval of the back-and-forth time of the forward and backward movement of the suction port body 16 is long and the suction port body 16 is moving slowly, the difference between the assisting force and the resistance force is set to the larger second difference to prioritize the assistance for traveling by the forward-rotating rotary cleaning member 28.

[0166] Incidentally, when it is estimated that the interval of the reciprocating time of the suction port body 16 for forward and backward movement, or the cycle of the forward and backward movement of the suction port body 16 is short and the suction port body 16 is moving at high speed, it is presumed that the user of the vacuum cleaner 1 is in a hurry to perform cleaning. In this case, even if the power consumption of the secondary battery 13 increases and the operation time is shortened, it is suitable for the user's benefit to enhance the dust removal ability.

[0167] Therefore, the magnitude of the resistance force that generates the first difference is set to be larger than the resistance force that generates the second difference. When the estimated time interval for reciprocation is shorter than a predetermined time interval, the driving force difference control circuit 99 sets the difference between the assisting force and the resistance force as the first difference, and increases the magnitude of the resistance force compared to the magnitude of the resistance force when the estimated time interval is equal to or longer than the predetermined time interval. In other words, when the estimated time interval for reciprocation is equal to or longer than the predetermined time interval, the difference between the assisting force and the resistance force is set as the second difference, and the magnitude of the resistance force is smaller than the magnitude of the resistance force when the estimated time interval is shorter than the predetermined time interval. By doing so, the suction port body 16 can achieve an appropriate balance between the self-propelling force that suits the user's characteristics and intentions and the dust scraping ability. In this case, if the second difference is larger than the first difference, the driving force difference control circuit 99 may maintain the propulsive force or may also change the propulsive force together with the resistance force.

[0168] Also, it is difficult for a user with weak arm strength to move the suction port body 16 at high speed. That is, when it is estimated that the interval of the reciprocating time of the suction port body 16 for forward and backward movement, or the cycle of the forward and backward movement of the suction port body 16 is long and the suction port body 16 is moving at low speed, it is presumed that the user of the vacuum cleaner 1 is a woman or a child with low arm strength. In this case, it is suitable for the user's benefit to reduce the power consumption of the secondary battery 13 and extend the operation time even at the expense of the dust removal ability.

[0169] Therefore, the magnitude of the driving force that generates the second difference is set to be smaller than the driving force that generates the first difference. When the estimated time interval for reciprocation is equal to or longer than a predetermined time interval, the driving force difference control circuit 99 sets the difference between the assisting force and the resistance force as the second difference, and reduces the magnitude of the driving force to be smaller than the magnitude of the driving force when the estimated time interval is shorter than the predetermined time interval. In other words, when the estimated time interval for reciprocation is shorter than the predetermined time interval, the difference between the assisting force and the resistance force is set as the first difference, and the magnitude of the driving force is larger than the magnitude of the driving force when the estimated time interval is equal to or longer than the predetermined time interval. By doing so, the suction port body 16 can achieve an appropriate balance between the self-propelling force that suits the characteristics and intentions of the user and the dust scraping ability. In this case, if the second difference is larger than the first difference, the driving force difference control circuit 99 may maintain the resistance force, or may change the resistance force together with the driving force. It is preferable to avoid a significant decrease in the dust removal ability of the rotary cleaning body 28 that rotates in the reverse direction later by maintaining the resistance force or setting a lower limit value for the resistance force.

[0170] These controls for increasing or decreasing at least one of the driving force and the resistance force in accordance with the high or low reciprocating speed of the suction port body 16 are not limited to two levels of high or low reciprocating speed, large or small driving force, and large or small resistance force, and may control a magnitude relationship of three or more levels, or may control a linear magnitude relationship.

[0171] Also, when the interval of the reciprocating time between the forward and backward movements of the suction port body 16 is short, it is presumed that the user has the arm strength to move the suction port body 16 quickly or has a request to finish the cleaning quickly. Therefore, the difference between the assisting force and the resistance force is set as the smaller first difference to prioritize the dust removal power of the rotary cleaning body 28 that rotates in the reverse direction.

[0172] Furthermore, when the interval of the reciprocating time between the forward and backward movements of the suction port body 16 is long, it is presumed that the user has low arm strength or is cleaning carefully. Therefore, the difference between the assisting force and the resistance force is set as the larger second difference to increase the self-propelling force of the suction port body 16 and provide a more comfortable operating feeling.

[0173] That is, the suction port body 16 can achieve an appropriate balance between the self-propelling force and the dust scraping ability that suit the characteristics and intentions of the user.

[0174] Also, when the suction port body 16 is retracted, the rear cleaning body 28R that rotates forward in the advancing order generates a greater driving force than the front cleaning body 28F that rotates reversely in the trailing order. If an attempt is made to advance the suction port body 16 in this situation, the user may experience a sense of discomfort as if being caught by the driving force that causes the suction port body 16 to try to move backward. Also, when attempting to advance the retracted suction port body 16, the force acting from the suction port body 16 to the surface f to be cleaned changes from a state of being lifted off the surface f to a state of applying a load to the surface f to be cleaned.

[0175] Therefore, the driving force difference control circuit 99 according to the present embodiment may operate the front motor 29F so that the difference between the assisting force and the resistance force becomes large immediately after it is determined that the traveling direction of the plurality of rotary cleaning bodies 28 has switched from retraction to advancement. By doing so, when the traveling direction of the suction port body 16 switches from retraction to advancement, the sense of discomfort such as being caught caused by the driving force that causes the suction port body 16 to try to move backward is reduced, and the ease of operation when starting to advance is improved.

[0176] As shown in FIG. 12, the acceleration A acting on the suction port body 16 reverses the tendency of increase and decrease when the suction port body 16 changes its traveling direction from forward to backward and from backward to forward. Therefore, as shown in FIG. 11, the suction port body 16 may be provided with an acceleration sensor 101 that detects the acceleration in the direction intersecting the rotation center line of the plurality of rotary cleaning bodies 28. The driving force difference control circuit 99 starts to determine the traveling direction based on the detection result of the current detection circuit 98 triggered by the reversal of the direction of the acceleration detected by the acceleration sensor 101. By doing so, the driving force difference control circuit 99 can more reliably determine whether the suction port body 16 is moving forward or backward. By acquiring the detection result of the acceleration sensor 101 at predetermined time intervals and averaging the slopes, the tendency of increase and decrease of the acceleration in the front-rear direction of the suction port body 16 can be grasped more accurately.

[0177] As described above, in the suction inlet body 16 and the vacuum cleaner 1 according to the present embodiment, a plurality of electric motors 29 are operated so that the assisting force generated by the forward-rotating rotary cleaning body 28 in the traveling direction is greater than the resistance force generated by the rearward-reversing rotary cleaning body 28 in the direction opposite to the traveling direction. Therefore, the suction inlet body 16 outputs a force that biases in the traveling direction. In the conventional suction inlet body, it was difficult to achieve both self-propelling power and dust removal ability on various cleaning surfaces with different properties. However, the suction inlet body 16 and the vacuum cleaner 1 according to the present embodiment can easily achieve both suitable self-propelling power and dust removal ability on various cleaning surfaces with different properties. These suitable self-propelling power and dust removal ability dramatically improve the comfort of the operation of the suction inlet body 16. Further, in the conventional suction inlet body, in order to cope with various cleaning surfaces with different properties, it was necessary to set the distance between the suction inlet body and the cleaning surface to a moderate value. However, the suction inlet body 16 and the vacuum cleaner 1 according to the present embodiment can bring the suction inlet main body 31 close to the cleaning surface f so that the suction ability is maximally exerted in common for various cleaning surfaces with different properties. Therefore, the dust removal ability of the rotary cleaning body 28 can be maximally exerted.

[0178] In addition, the suction inlet body 16 and the vacuum cleaner 1 according to the present embodiment can detect a change in the traveling direction based on the difference in the current values flowing through at least two electric motors 29 that separately rotationally drive at least two rotary cleaning bodies 28 having different rotational directions, or the difference in the change in these current values. Therefore, the suction inlet body 16 and the vacuum cleaner 1 can easily and surely grasp the traveling direction of the suction inlet body 16 without using a special device or detector.

[0179] Furthermore, the suction inlet body 16 and the vacuum cleaner 1 according to the present embodiment may detect a change in the traveling direction based on the current value flowing through the electric motor 29 that rotationally drives at least one forward-rotating rotary cleaning body, or the change in this current value. Therefore, the suction inlet body 16 and the vacuum cleaner 1 can easily and surely grasp the traveling direction of the suction inlet body 16 without using a special device or detector.

[0180] Further, the suction inlet body 16 and the vacuum cleaner 1 according to the present embodiment can detect a change in the traveling direction and determine in which direction the plurality of rotary cleaning bodies 28 are traveling across the rotation center line based on the duration of the peak current in which the current value flowing through the motor 29 that rotationally drives at least one rotary cleaning body 28 that rotates forward in advance exceeds a predetermined determination current Id. That is, the suction inlet body 16 and the vacuum cleaner 1 individually include a motor 29 that rotationally drives the rotary cleaning body 28 that rotates forward in advance and a motor 29 that rotationally drives the rotary cleaning body 28 that rotates backward later, and by individually detecting the current values flowing through these motors 29, it is possible to easily and surely grasp the traveling direction of the suction inlet body 16 without using a special device or detector.

[0181] Furthermore, the suction inlet body 16 and the vacuum cleaner 1 according to the present embodiment may start determining the traveling direction based on the detection result of the current detection circuit 98 triggered by the inversion of the direction of the acceleration in the front-rear direction of the suction inlet body 16 detected by the acceleration sensor 101. Therefore, the suction inlet body 16 and the vacuum cleaner 1 can detect the change in the traveling direction with higher accuracy and more precisely than simply detecting the change in the traveling direction only with the acceleration sensor 101. When the change in the traveling direction is detected only with the acceleration sensor 101, if the suction inlet body 16 once stops or moves at a substantially constant speed and the detection of the acceleration becomes extremely small, there is a risk of misdetecting or missing the detection of the change in the traveling direction.

[0182] In addition, the suction inlet body 16 and the vacuum cleaner 1 according to the present embodiment estimate the rolling resistance due to friction of the cleaning surface f in contact with the rotary cleaning body 28 rotationally driven by the electric motor 29 based on the current value flowing through at least one electric motor 29 of the plurality of electric motors 29, the change in the current value, or the magnitude of the peak current when the current value exceeds a predetermined second determination current. When the estimated rolling resistance is greater than a predetermined rolling resistance, the first driving power is sent to the plurality of electric motors 29. When the estimated rolling resistance is less than or equal to the predetermined rolling resistance, the second driving power smaller than the first driving power is sent to the plurality of electric motors 29. Therefore, the suction inlet body 16 and the vacuum cleaner 1 can maximize the dust collection performance with efficient power consumption suitable for the properties of the cleaning surface f. Further, even on a cleaning surface where the rolling resistance of the rotary cleaning body 28 changes between the pile direction and the reverse pile direction like a carpet, the suction inlet body 16 and the vacuum cleaner 1 can maximize the dust collection performance with efficient power consumption suitable for the properties of the cleaning surface f in both the case of moving forward with respect to the pile direction and moving backward with respect to the reverse pile direction and the case of moving backward with respect to the pile direction and moving forward with respect to the reverse pile direction, for any traveling direction.

[0183] In addition, the suction inlet body 16 and the vacuum cleaner 1 according to the present embodiment estimate the time interval during which the plurality of rotary cleaning bodies 28 travel back and forth in a direction intersecting the rotation center line based on the occurrence interval of the peak current when the current value flowing through at least one electric motor 29 of the plurality of electric motors 29 exceeds a predetermined third determination current Id3. When the estimated time interval is shorter than a predetermined time interval, the difference between the assisting force and the resistance force is set as the first difference. When the estimated time interval is equal to or longer than the predetermined time interval, the difference between the assisting force and the resistance force is set as the second difference greater than the first difference. Therefore, it is possible to achieve an appropriate balance between the self-propelling power and the dust scraping ability that match the characteristics and intentions of the user.

[0184] Furthermore, when a plurality of rotary cleaning members 28 move in a direction parallel to the rotation center line, the suction inlet body 16 and the vacuum cleaner 1 according to the present embodiment may be provided with a resistance reduction mechanism 81 that protrudes from the bottom surface 31a of the suction inlet main body 31 to move the suction inlet main body 31 away from the surface to be cleaned f and reduce the rolling resistance of the plurality of rotary cleaning members 28. **A. Therefore, the suction inlet body 16 and the vacuum cleaner 1 can reduce the contact amount between the rotary cleaning member 28 and the surface to be cleaned f not only when the suction inlet body 16 is moved in the front-rear direction, but also when the suction inlet body 16 is moved in the left-right direction, improving the ease of operation in all four directions of front, rear, left, and right.

[0185] In addition, when it is determined that the traveling direction of the plurality of rotary cleaning members 28 has switched from backward to forward, the suction inlet body 16 and the vacuum cleaner 1 according to the present embodiment operate a plurality of electric motors 29 so that the difference between the assisting force of the front cleaning member 28F and the resistance force of the rear cleaning member 28R becomes large. Therefore, when the traveling direction of the suction inlet body 16 switches from backward to forward, the suction inlet body 16 and the vacuum cleaner 1 reduce the sense of discomfort such as snagging caused by the propulsive force that tries to move the suction inlet body 16 in the backward direction, improving the ease of operation when starting to move forward.

[0186] Therefore, according to the suction inlet body 16 and the vacuum cleaner 1 according to the present embodiment, it is possible to achieve both the ease of traveling and the dust collection performance corresponding to various surfaces to be cleaned, by providing the rotary cleaning members 28 that rotate forward in the forward order and the rotary cleaning members 28 that rotate backward in the reverse order.

[0187] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and its equivalent scope.

Explanation of Reference Numerals

[0188] 1... Vacuum cleaner, 11... Handle, 12... Cleaner body, 13... Secondary battery, 15... Extension tube, 16... Suction inlet body, 17... Main body case, 17a... Front half, 17b... Rear half, 18... Electric blower, 19... Dust separation and collection unit, 21... Main body control unit, 23... Main body connection port, 26... Input unit, 26a... Operation start switch, 26b... Operation stop switch, 26c... Brush switch, 27... Suction port, 28... Rotating cleaning body, 28F... Front cleaning body, 28Fa... Top of the front cleaning body, 28R... Rear cleaning body, 28Ra... Top of the rear cleaning body, 28pr... Leading rotating cleaning body, 28fo... Trailing rotating cleaning body, 29... Electric motor, 29F... Front motor, 29R... Rear motor, 29a... Output shaft, 29pr... Leading drive motor, 29fo... Trailing drive motor, 31... Suction inlet main body, 31a... Bottom surface, 32... Connecting pipe, 35... Lower case, 36... Upper case, 38... Rotating connecting pipe, 39... Swing connecting pipe, 41... Power transmission mechanism, 41F... Front transmission mechanism, 41R... Rear transmission mechanism, 42... Suction inlet body control unit, 45... Suction chamber, 46... Cleaning body chamber, 46F... Front cleaning body chamber, 46R... Rear cleaning body chamber, 47... Permeable wall, 47A... First permeable wall, 47B... Second permeable wall, 47BL, 47BR... Divided permeable wall, 48... Air duct cover, 49... Air duct narrowing body, 50... Roll, 51... Electric motor chamber, 51F... Front motor chamber, 51R... Rear motor chamber, 52... Machine room, 52F... Front machine room, 52R... Rear machine room, 53... Control room, 55... Window part, 55F... Front cleaning body window, 55R... Rear cleaning body window, 55RL, 55RR... Divided window, 56... Transparent member, 57... Relay pipe, 59... Brush bristles, 61... Driving gear, 62... Driven gear, 63... Belt, 65... Partition wall, 65F... Front partition wall, 65R... Rear partition wall, 66... Dust removal protrusion, 66F... Front protrusion, 66R... Rear protrusion, 68... Curved surface, 71... Inclined surface, 72... Guide surface, 73... Hole, 75... Protrusion, 81, 81A... Resistance reduction mechanism, 82, 82A... Guide part, 83... Roll, 85, 85A... Inductive magnetic force part, 87, 87A... Fixed magnet, 88... Moving magnet, 91... Electric wire, 92... Grounded side electric wire, 93... Non-grounded side electric wire, 95... Control power generation circuit, 96... Reference voltage generation circuit, 97... Drive circuit, 98... Current detection circuit, 99... Driving force difference control circuit, 101... Acceleration sensor.

Claims

1. A plurality of rotary cleaning bodies having parallel rotation center lines, A plurality of electric motors that generate the rotational driving force of the plurality of rotary cleaning bodies, A current detection circuit that individually detects the current flowing through each of the electric motors, A control unit that controls the operation of the plurality of electric motors, and is provided with, The control unit, Based on the detection result of the current detection circuit, it is determined in which direction the plurality of rotary cleaning bodies are moving across the rotation center line, At least one of the electric motors is operated so as to rotate in the forward rotation direction that assists the rotation of the rotary cleaning body that precedes in the traveling direction, At least one of the other electric motors is operated so that at least one of the rotary cleaning bodies that follows the preceding rotary cleaning body rotates in the reverse rotation direction, The plurality of electric motors are operated so that the assisting force generated by the rotary cleaning body rotating in the forward rotation direction in the traveling direction is greater than the resistance force generated by the rotary cleaning body rotating in the reverse rotation direction in the opposite direction of the traveling direction, Based on the difference in the current values flowing through at least two of the electric motors that separately rotate at least two of the rotary cleaning bodies having different rotation directions, or the difference in the change in the current values flowing through at least two of the electric motors that separately drive at least two of the rotary cleaning bodies having different rotation directions, the change in the traveling direction is detected, and it is determined in which direction the plurality of rotary cleaning bodies are moving across the rotation center line. A suction port body.

2. The control unit detects a change in the traveling direction based on the length of the duration of the peak current in which the current value flowing through the electric motor that rotationally drives at least one of the rotary cleaning bodies rotating in the forward rotation direction exceeds a predetermined determination current, and determines in which direction the plurality of rotary cleaning bodies are moving across the rotation center line. The suction port body according to Claim 1.

3. An acceleration sensor that detects the acceleration in the direction in which the plurality of rotary cleaning bodies cross the rotation center line is provided, Based on the reversal of the direction of the acceleration, the determination of the traveling direction based on the detection result of the current detection circuit is started. The suction port body according to Claim 1 or 2.

4. The control unit estimates the rolling resistance due to the friction of the surface to be cleaned that the rotary cleaning body rotationally driven by the electric motor contacts based on the current value, the change in the current value, or the magnitude of the peak current in which the current value exceeds a predetermined determination current flowing through at least one of the plurality of electric motors, When the estimated rolling resistance is greater than a predetermined rolling resistance, the first driving power is sent to the plurality of electric motors. When the estimated rolling resistance is less than or equal to the predetermined rolling resistance, the second driving power smaller than the first driving power is sent to the plurality of electric motors. The suction port body according to any one of claims 1 to 3.

5. Based on the generation interval of the peak current in which the current value flowing through at least one of the plurality of electric motors exceeds a predetermined determination current, the control unit estimates the time interval during which the plurality of rotary cleaning members move back and forth in a direction intersecting the rotation center line. When the estimated time interval is shorter than a predetermined time interval, the difference between the assisting force and the resistance force is set as the first difference. When the estimated time interval is equal to or longer than the predetermined time interval, the difference between the assisting force and the resistance force is set as the second difference larger than the first difference. The suction port body according to any one of claims 1 to 4.

6. The magnitude of the resistance force that generates the first difference is greater than the resistance force that generates the second difference. The suction port body according to claim 5.

7. The magnitude of the resistance force that generates the second difference is smaller than the resistance force that generates the first difference. The suction port body according to claim 5.

8. A main body that rotatably supports the plurality of rotary cleaning members, When the plurality of rotary cleaning members move in a direction parallel to the rotation center line, a resistance reducing mechanism that protrudes from the bottom surface of the main body to move the main body away from the surface to be cleaned and reduces the rolling resistance of the plurality of rotary cleaning members. The suction port body according to any one of claims 1 to 7.

9. A joint portion that receives a force to advance the plurality of rotary cleaning members while applying a load to the surface to be cleaned and receives a force to retract the plurality of rotary cleaning members while removing the load from the surface to be cleaned. Immediately after the control unit determines that the traveling direction of the plurality of rotary cleaning members has switched from backward to forward, the control unit operates the plurality of electric motors so that the difference between the assisting force and the resistance force increases. The suction port body according to any one of claims 1 to 6.

10. A vacuum cleaner body, An electric blower housed in the vacuum cleaner body and generating a negative pressure, A suction port body according to any one of claims 1 to 9 that is fluidly connected to the electric blower. An electric vacuum cleaner comprising the same.

11. A plurality of rotary cleaning members having parallel rotation center lines, A plurality of electric motors that generate a rotational driving force for the plurality of rotary cleaning members, A current detection circuit that individually detects the current flowing through each of the electric motors; A control unit that controls the operation of the plurality of electric motors, and the control unit judges, based on the detection result of the current detection circuit, in which direction among the directions intersecting the rotation center line the plurality of rotary cleaning members are advancing; operates at least one of the electric motors so as to rotate in the forward rotation direction in which the rotary cleaning member preceding in the advancing direction assists the advancement; operates at least one other of the electric motors so that at least one of the rotary cleaning members that follows the preceding rotary cleaning member rotates in the reverse rotation direction; operates the plurality of electric motors so that the assisting force generated in the advancing direction by the rotary cleaning member rotating in the forward rotation direction is greater than the resistance force generated in the direction opposite to the advancing direction by the rotary cleaning member rotating in the reverse rotation direction; and a vacuum cleaner that detects a change in the advancing direction and judges in which direction among the directions intersecting the rotation center line the plurality of rotary cleaning members are advancing, based on a difference in current values flowing through at least two of the electric motors that individually rotationally drive at least two of the rotary cleaning members having different rotation directions, or a difference in changes in current values flowing through at least two of the electric motors that individually drive at least two of the rotary cleaning members having different rotation directions.

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