JP2005034176A - Extension pipe and vacuum cleaner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an extension pipe capable of securing a passage of necessary and sufficient size inside the pipe while preventing it from being thick. <P>SOLUTION: It is assumed that the extension pipe 30 is provided with extendably and contractibly combined outer pipe 40 and inner pipe 50 and leads an air flow including dust. The inner pipe 50 consists of a metallic inner pipe body 52 and an inner pipe end member 51 made of synthetic resin. The inner pipe body 52 is movably inserted into the outer pipe 40. The inner pipe end member 51 projects from one end of the outer pipe 40 and connected to one end of the inner pipe body 52. As the inner pipe body 52 is made of metal, the thickness of the extension pipe is reduced while obtaining a required strength. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a telescopic extension pipe that guides a dust-containing airflow to a vacuum cleaner body, and a vacuum cleaner including the extension pipe.
[0002]
[Prior art]
In many cases, the vacuum cleaner is used by connecting a detachable extension pipe between a handle portion at the tip of the dust suction hose connected to the vacuum cleaner body and a connection pipe of the suction port body.
[0003]
Conventionally, as an extension tube, an extendable extension tube including an outer tube and an inner tube movably inserted in the outer tube is known (see, for example, Patent Document 1).
[0004]
[Patent Document 1]
JP 2001-17365 A (paragraphs 0023-0061, FIGS. 1-6)
[0005]
[Problems to be solved by the invention]
Patent Document 1 does not mention the material of the outer tube and the inner tube of the extension tube, but it is well known that these are made of synthetic resin.
[0006]
In order to press the suction port against the surface to be cleaned during cleaning, a diagonally downward force is applied to the extension pipe from the handle. Therefore, the extension tube needs to be strong enough to withstand such a force. As described above, in the configuration in which both the inner tube and the outer tube are made of synthetic resin, the strength is obtained by increasing the thickness of both tubes.
[0007]
For this reason, when making an extension pipe giving priority to the thickness of the inner pipe that defines the minimum cross-sectional area of the pipe passage of the extension pipe, the extension pipe must be made thicker, giving the design a harsh feeling. In addition, it is not preferable, and if the user's hand is small, it may be difficult to grasp and it is not preferable in terms of extending / contracting the extension tube. On the other hand, when the extension pipe is made with priority given to its thickness so that the outer pipe does not become thick, the inner pipe becomes thin, so a sufficiently small minimum cross-sectional area is secured in the pipe passage. It is easy to disturb.
[0008]
The problem to be solved by the present invention is to obtain an extension pipe capable of ensuring a necessary and sufficient size of the pipe passage while suppressing an increase in thickness and a vacuum cleaner including the extension pipe.
[0009]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides a metal inner tube body that is movably inserted into an outer tube and a metal inner tube body that is movably inserted into the outer tube, and one end of the inner tube body. A synthetic resin inner tube end member connected and protruding from one end of the outer tube is provided.
[0010]
In the present invention, since the strength of the metal inner tube main body of the inner tube that defines the minimum cross-sectional area of the tube passage of the extension tube is larger than that of the inner tube made of synthetic resin, it is movably inserted into the outer tube. The wall thickness of the inner pipe body can be reduced while ensuring the strength required for the inner pipe body. For this reason, when giving priority to the thickness of the inner tube, it is possible to reduce the thickness of the outer tube. Conversely, when giving priority to the thickness of the outer tube, the diameter of the inner tube is increased. It is possible to increase the minimum cross-sectional area of the pipe passage.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
[0012]
The vacuum cleaner denoted by reference numeral 1 in FIG. 1 includes a cleaner body 2, a dust suction hose 20, an extension pipe 30, and a suction port body 70.
[0013]
The vacuum cleaner body 2 is provided with, for example, a dust collection chamber (not shown) forming a dust collection unit in a main body case 10 formed by connecting an upper case 11 and a lower case 12, and an electric blower 16 and a cord reel device (not shown). Not built in).
[0014]
For example, a suction port 13 communicating with the dust collecting chamber is formed in the front portion of the main body case 10. The main body case 10 is provided with an opening / closing lid 14 for opening and closing an opening formed above the dust collection chamber, and a filter 17 made of a paper bag or the like is accommodated in the dust collection chamber through the opening. Reference numeral 15 in FIG. 1 denotes a traveling wheel, and the cleaner body 2 can be moved along the floor surface via a rotating wheel (not shown) attached to the lower surface of the front portion of the lower case 12. .
[0015]
The dust suction hose 20 has a flexible hose body 21 formed in a bellows shape, a connection tool 22 connected to one end of the hose body 21, and a handle 23 connected to the other end of the hose body 21. is doing. The dust suction hose 20 can removably fit the connector 22 to the suction port 13 and is connected to the main body case 10 by this fitting.
[0016]
A handle 24 is provided integrally with the handle portion 23. The handle 24 is provided with a plurality of control switches 25 for controlling the electric blower 16. Control signals from these control switches 25 are sent from a control device (not shown) in the main body case 10 via a wire (not shown) wired in the hose body 21 and a connection pin (not shown) of the connector 22 to which the wire is connected. ).
[0017]
A fitting portion 26 to which the extension tube 30 is detachably connected is formed at the distal end portion of the handle portion 23. For example, a female connector (not shown) that is in electrical contact with a connection pin 47a (described later) of the extension tube 30 is provided on the fitting portion 26, for example. A connecting piece of this connector is connected to an electric wire wired in the hose body 21 and is electrically connected to a power source via the cord reel device.
[0018]
A connection holding means 27 is provided at the distal end of the handle portion 23, for example, located above the fitting portion 26. The connection holding means 27 includes an engaging claw (not shown) that holds the extension pipe 30 connected to the fitting portion 26 in a connected state, an operation button 27a for releasing the connected state, and the like.
[0019]
The extension pipe 30 used detachably connected to the fitting portion 26 of the dust suction hose 20 will be described with reference to FIGS. The extension tube 30 includes an outer tube 40 and an inner tube 50 and is configured to be extendable and contractible.
[0020]
As shown in FIGS. 2, 3, 5, and 6, the outer tube 40 includes an outer tube main body 41 and a cover 42 that is integrally attached to the upper surface side of the outer tube main body 41. Both the outer tube main body 41 and the cover 42 are made of hard synthetic resin. A support base 48 is formed integrally with a non-connection end portion (an end portion disposed near the suction port body 70 in use) of the outer tube body 41 by forming a wire cover through hole 48d. The wire cover through-holes 48d extend in the axial direction of the outer tube main body 41, and both ends in the axial direction are open.
[0021]
As shown in FIGS. 2 and 3, the non-connection end portion 41 </ b> A of the outer tube main body 41 is fitted with a larger inner diameter than other portions of the outer tube main body 41 from the end surface to a predetermined depth. A hole 41a is formed. A first guide ring 43 is accommodated in the inner part of the fitting hole 41a, and a second guide ring 45 having a flange 44 is accommodated on the opening end side. Furthermore, the seal ring 46 is accommodated in the fitting hole 41a so as to be sandwiched between the guide ring 43 and the guide ring 45 made of synthetic resin. The flange portion 44 is formed with an electric wire cover through hole 44a facing the electric wire cover through hole 48d and communicating with the storage portion 31 described later through the electric wire cover through hole 48d.
[0022]
Both guide rings 43 and 45 guide the inner tube main body 52 when the inner tube main body 52 described later moves in the outer tube main body 41 in the axial direction. The seal ring 46 functions to prevent external air from flowing in between the inner peripheral surface of the outer tube main body 41 and the outer peripheral surface of the inner tube main body 52.
[0023]
In the upper part of the outer tube main body 41 in FIG. 2, a guide groove 41 b that extends in the axial direction is formed in the outer tube main body 41. A stopper 57 provided on the outer surface of the insertion end 51B of the inner tube main body 52 is slidably fitted in the guide groove 41b. The stopper 57 prevents the inner tube main body 52 from rotating with respect to the outer tube 40 in the circumferential direction. Further, the stopper 57 can abut against the partition portion 41be of the outer tube main body 41 that forms the boundary between the guide groove 41b and the fitting hole 41a, and the inner tube 50 is prevented from being detached from the outer tube main body 41 by this contact. It is supposed to be.
[0024]
A cover 42 is attached to the upper side of the outer tube main body 41 by screws 81 and locking bodies 82 shown in FIG. A storage portion 31 (see FIGS. 2, 3, and 6) sealed by the inner surface of the cover 42 and the outer peripheral surface of the outer tube main body 41 is formed extending in the axial direction of the outer tube main body 41. The storage portion 31 is isolated from the inner space of the outer tube main body 41, that is, from the tube passage through which the dust-containing airflow passes during cleaning. On the outer peripheral surface of the outer tube main body 41 facing the storage portion 31, two conductive rails 47 formed of a thin plate made of a conductive material are spaced apart from each other by a predetermined distance as shown in FIG. It is fixed by a screw 80 (see FIG. 5).
[0025]
A pair of connection pins 47a made of a conductive material as a first terminal is connected to an end portion of the outer tube 40 opposite to the non-connection end portion 41A, that is, the connection side end portion 41B inserted and connected to the fitting portion 26. Is provided so as to protrude from the storage portion 31. These connection pins 47 a are electrically connected to the conductive rails 47 in the storage portion 31. As the connection side end 41B is inserted into the fitting portion 26, the connection pin 47a is inserted and connected to the female connector of the handle portion 23.
[0026]
As shown in FIG. 5, the support base 48 of the outer tube main body 41 is formed with a locking member through hole 48 a that opens to the upper surface, and a spring receiving projection 48 b that protrudes from the upper surface. Further, the support base 48 is formed with a bearing portion 48c that is positioned between the locking body through hole 48a and the spring receiving projection 48b and faces each other in the width direction of the support base 48.
[0027]
As shown in FIG. 5, two locking holes 41f (in FIG. 5, only one side) are located on both sides in the width (diameter) direction of the non-connecting end portion 41A of the outer tube main body 41, respectively. (Shown) is formed. These locking holes 41f are configured to engage with plate-like locking claws 82a or hook-like locking claws 82b of the locking body 82.
[0028]
A boss 41k having a screw hole 41i is formed on the connection side end 41B side of the outer tube main body 41, and a pair of engagement grooves 41g for attaching the connection pin 47a is formed. An annular groove 41h is formed in the connection side end portion 41B, and the seal ring 46a is fitted and attached to the annular groove 41h. The seal ring 46a functions to prevent the inflow of air from the outside into the fitting portion 26 when the connection side end portion 41B of the outer tube 40 is fitted to the fitting portion 26 of the handle portion 23. Is.
[0029]
As shown in FIG. 5, a pair of fitting ribs 41c facing each other and extending in the axial direction are formed on the upper surface of the outer tube main body 41, and a conductive rail 47 is screwed between these fitting ribs 41c. The cover 42 has a side wall 42a fitted from the outside to the fitting rib 41c, and the cross section in the width direction is formed in a substantially U shape as shown in FIG. A rectangular opening 42b for exposing an operation knob 64 of the fixing means 60 described later is formed on the upper surface of the cover 42 that covers the support 48.
[0030]
A fitting hole 42c into which the locking body 82 is fitted is formed in both side walls 42a at one end of the cover 42 in which the opening 42b is formed. A hole 42 d through which the screw 81 passes is formed at the other end of the cover 42. The screw 81 is inserted into the hole 42d and screwed into the screw hole 41i of the boss 41k, and the locking member 82 is fitted into the fitting hole 42c to lock the locking claw 82a and the locking claw 82b. By engaging with the hole 41f, the cover 42 is attached to the outer tube main body 41 as shown in FIG.
[0031]
Although not shown, an engagement groove corresponding to a pair of engagement grooves 41 g formed in the outer tube main body 41 is formed at the other end of the cover 42. By connecting the cover 42 to the outer tube main body 41, the engagement groove (not shown) and the engagement groove 41g are combined so as to sandwich the connection pin 47a.
[0032]
2, 3, 5, 6, and the like, the inner tube 50 includes an inner tube end member 51, an inner tube main body 52, and an electric wire cover 53.
[0033]
The inner tube main body 52 is made of a metal, preferably a light metal, specifically aluminum or an alloy thereof, and is formed into a cylindrical shape shorter than the outer tube main body 41. The inner tube main body 52 is inserted into the outer tube main body 41 so as to be movable along the axial direction of the outer tube main body 41. The insertion end 51B of the inner pipe main body 52 located on the side opposite to the inner pipe end member 51 is provided with a recess 51h, and the stopper 57 is attached to the recess 51h. The stopper 57 is movable in a guide groove 41b formed in the outer tube main body 41 so as to extend in the axial direction.
[0034]
The inner pipe end member 51 is formed of the same kind of synthetic resin as the outer pipe main body 41 and is connected to one end of the inner pipe main body 52. The inner peripheral surface of the inner tube end member 51 and the inner peripheral surface of the outer tube main body 41 are continuous with each other without providing a step. As shown in FIG. 3, the inner tube end member 51 protrudes from one end portion of the outer tube main body 41 to the outside of the outer tube main body 41 even when the inner tube main body 52 is inserted into the outer tube main body 41 most deeply. Is to be arranged. In FIG. 3, reference numeral 52F denotes a flange formed at one end of the inner tube main body 52 and embedded in the inner tube end member 51, and the inner tube end member 51 is prevented from coming off by the flange 52F.
[0035]
A knob arrangement portion 51E is provided on the upper surface of the inner tube end member 51 (the surface that is the upper side during use). The knob placement part 51E is provided with ribs 51b having U-shaped groove bearings 51a located on both sides in the width direction and facing each other, and positioning ribs 51c are formed between the ribs 51b. ing. Between the rib 51b and the positioning rib 51c, a conductive connection piece 54a made of a metal spring plate is sandwiched and disposed. The connection piece 54a constitutes a connector. A U-shaped rib 51d is formed in the knob placement portion 51E, and an engaging claw through hole 51e is formed inside the U-shaped rib 51d.
[0036]
A through hole 51f is formed in the flange-shaped front wall 51g of the knob placement portion 51E. A pair of connection pins (not shown) provided in a connection pipe 72 (described later) of the suction port body 70 is inserted into the through hole 51f. The metal connection pin inserted into the through hole 51f contacts the connection piece 54a.
[0037]
The electric wire cover 53 includes a cover body 58 and a cover back cover 59 that extend in the axial direction of the inner tube 50. The cover body 58 and the cover back cover 59 are made of synthetic resin.
[0038]
The cover main body 58 has a knob cover portion 58a at one end portion in the longitudinal direction, and a plurality of engagement portions, for example, engagement holes 58b are formed at predetermined intervals along the longitudinal direction in portions removed from the cover body 58. Yes. These engaging portions can be made of recesses instead of holes. The knob cover portion 58a covers the knob arrangement portion 51E and is connected to the arrangement portion 51E by claw engagement. By this connection, the cover main body 58 is attached to the inner pipe 50 along the inner pipe main body 52 in a cantilever state. An opening 58c is formed in the knob cover portion 58a.
[0039]
A cover back cover 59 is attached by claw engagement to the back surface of the portion of the cover body 58 that is removed from the knob cover portion 58a, and a wiring passage 53a is formed between them. The wiring passage 53a is isolated from the inner space of the inner tube 50, that is, the inner passage through which the dust-containing airflow passes during cleaning. A plurality of electric wires 54 for power feeding and signal transmission / reception are passed through the wiring passage 53a. An insulating coating is used for the electric wire 54.
[0040]
A mounting base 55 made of an insulating material is attached to the other end of the cover main body 58 with screws 84. A pair of sliding contact pieces 56 are attached to the mounting base 55 as second terminals. These sliding contact pieces 56 are made of conductive metal plate springs, and can move along the conductive rails 47 while being elastically in contact with the pair of conductive rails 47 individually. One end of the electric wire 54 is connected to the sliding contact piece 56. The other ends of the electric wires 54 are connected to the connection pieces 54a.
[0041]
Between the knob arrangement part 51E and the knob cover part 58a covered with the knob arrangement part 51E, an operation knob 92 included in a fixing means 90 for holding the connection pipe 72 of the suction port body 70 in a connected state is arranged. Specifically, the shafts 93 protruding from both sides of the operation knob 92 are pivotally supported from below by the bearings 51a of the ribs 51b, and from above by bearings (not shown) formed on the knob cover portion 58a so as to face the bearings 51a. It is pivotally supported. The operation knob 92 attached to the inner pipe main body 52 by such a shaft support has an engaging claw 94 and is urged by an urging spring 95. When the operation knob 92 is urged by the urging spring 95, the engagement claw 94 penetrates the engagement claw through hole 51e and protrudes into the inner tube main body 52. ing.
[0042]
The inner tube 50 configured as described above is inserted into the outer tube main body 41 of the outer tube 40 with the inner tube main body 52 as the leading end of the insertion end 51B to which the stopper 57 is attached, and the electric wire cover 53 is slid into the sliding piece 56. Is inserted into the storage portion 31 with the end portion attached to the head as the head, and is combined with the outer tube 40 so as to be extendable and contractible. The electric wire cover 53 is inserted into the storage portion 31 through the electric wire cover through hole 44 a of the first guide ring 43 and the electric wire cover through hole 48 d formed inside the support base 48. Actually, a cover 42 is attached to the outer tube main body 41 after this penetration, and the storage portion 31 is made. Along with the attachment of the inner tube 50 to the outer tube 40, the sliding contact piece 56 accommodated in the storage portion 31 was pressed against the conductive rail 47, and the inner tube 50 was moved in the axial direction with respect to the outer tube 40. In this case, the sliding contact piece 56 moves while maintaining the pressure contact state with the conductive rail 47.
[0043]
The storage unit 31 is provided with fixing means 60 for positioning the inner tube 50 with respect to the outer tube 40. That is, as shown in FIGS. 3 to 5, the fixing means 60 moves in a direction to disengage the engaging body 61 from the engaging hole 58 b of the electric wire cover 53, and to disengage the engaging body 61 from the engaging hole 58 b. The operation knob 64 having a pressing projection 65b that presses the arm 66 and the locking body 61 to engage with the engagement hole 58b, and the biasing direction in which the locking body 61 is engaged with the engagement hole 58b. The biasing spring 69 biases the operation knob 64.
[0044]
The locking body 61 is formed in a cylindrical shape and has an annular flange 62 on the upper end side in the axial direction thereof, and the lower end portion is an engagement portion that is inserted into and removed from the engagement hole 58b. ing. The operation knob 64 includes a knob portion 65 formed in a bottomed box shape having a ceiling wall 65a and opened downward, and a pair of arms 66 that are integrally attached to the knob portion 65 and spaced apart from each other. Arm plate 67. A shaft 68 is formed on both side walls of the knob portion 65. The shaft 68 is pivotally supported from the lower side to the bearing portion 48c and from the upper side to a bearing portion (not shown) formed on the cover 42 so as to be opposed to the bearing portion 48c, thereby the operation knob 64 is supported by the support base. 48 is mounted for rotation.
[0045]
The arm plate 67 is integrated with the knob portion 65 by bonding or the like on both side walls of the knob portion 65. The front ends of both arms 66 are formed with contact protrusions 66a as contact portions having a curved cross section. The contact protrusion 66 a is in contact with the lower surface of the flange portion 62 of the locking body 61. Therefore, as the operation knob 60 rotates clockwise in FIGS. 2 and 3 with the shaft 68 as a fulcrum, the locking body 61 is moved upward. The engaging portion can be detached from the engaging hole 58b.
[0046]
As shown in FIG. 3, a pressing projection 65b and a spring receiving projection 65c are formed on the inner surface of the ceiling wall 65a of the knob portion 65 with a shaft 68 therebetween. Between the spring receiving projection 65c and the spring receiving projection 48b of the support base 48, a coiled biasing spring 69 is sandwiched for biasing the operation knob 60 to rotate counterclockwise in FIG. .
[0047]
For this reason, when the operation knob 60 is rotated counterclockwise in FIG. 3 by the biasing spring 69, the pressing protrusion 65 b presses the upper end surface of the locking body 61 to engage the locking body 61. The portion functions to engage with the engagement hole 58b. Further, when the operation portion 64a is pressed by the fingertip against the urging force of the urging spring 69 and the operation knob 60 is rotated in the clockwise direction, a force that presses the locking body 61 from above is apparent. Since it disappears, the locking member 61 moves upward and is detached from the engagement hole 58b by the spring force of the arm 66 that is in contact with the lower surface of the flange 62. In this detached state, the inner tube 50 can be moved in the axial direction with respect to the outer tube 40 by hand. As a result, the extension tube 30 can be expanded and contracted and adjusted to a desired length.
[0048]
Since the locking body 61 is engaged with the engagement hole 58b at the desired position by this length adjustment, the extension tube 30 is desired even if a strong force is applied to push the inner tube 50 into the outer tube 40 during cleaning. Therefore, the operability of the suction port body 70 during cleaning is not impaired.
[0049]
As described above, the extension tube 30 having the above-described configuration has the inner tube main body 52 of the inner tube 50 made of metal, so that the strength of the inner tube main body 52 is made of the entire inner tube made of synthetic resin. The inner tube main body 52 can be made thinner to ensure the strength required to withstand the operating force applied to the extension tube 30 during cleaning.
[0050]
For this reason, when the thickness of the inner pipe main body 52 that defines the minimum passage cross-sectional area in the extension pipe 30 through which dust-containing air passes during cleaning is set so as to ensure a predetermined passage cross-sectional area, The thickness of the outer tube 40 into which the inner tube main body 52 is movably inserted can be reduced by an amount corresponding to the thinner inner tube main body 52. By reducing the diameter, it is possible to suppress the extension tube 30 from giving a tight feeling, which is preferable in terms of design. Furthermore, even when the size of the user's hand is small, the extension tube 30 having a thickness that can be easily gripped when the extension tube 30 is expanded or contracted can be obtained. Of course, by reducing the diameter, the amount of material used to form the outer tube 40 can be reduced, and the weight and cost can be reduced.
[0051]
Conversely, when priority is given to the thickness of the outer tube 40, the inner tube that defines the smallest passage cross-sectional area in the extension tube 30 by thinning the inner tube body 52 inserted into the outer tube body 41. The inner diameter of the main body 52 can be increased. That is, it is possible to increase the minimum passage cross-sectional area, and it is possible to provide the extension pipe 30 that facilitates the passage of the dust-containing airflow.
[0052]
In the case of this embodiment, since the inner pipe body 52 is made of an aluminum-based metal, the inner pipe 50 can be lightened. As a result, the suction port body 70 side becomes lighter when viewed from the handle portion 23, and the operation of moving the suction port body 70 via the extension pipe 30 with the handle portion 23 becomes easy.
[0053]
The suction port body 70 shown in FIG. 1 is detachably fitted to and connected to the inner tube end member 51 that forms the tip of the inner tube 50. The suction port body 70 includes a suction port body main body 71 and a connection pipe 72. The suction port body 71 has a suction opening on the lower surface. The suction port body 71 incorporates a rotatable rotary cleaning body 73 partially protruding from the suction opening, and includes an electric motor 74 for driving the electrical components such as the rotary cleaning body 73 and a motor control circuit (not shown). Etc. are built-in.
[0054]
The connecting pipe 72 is located at the rear part of the suction port body 71 and at the center part in the width direction, and is rotatably attached via a joint structure (not shown). A pair of connection pins (not shown) that are electrically connected to the motor 74 and the motor control circuit are provided on both sides of the end of the connection pipe 72 that is fitted to the inner pipe end member 51. These connection pins are inserted into the through holes 51f of the front wall 51g and are electrically connected to the connection pieces 54a.
[0055]
As shown in FIG. 3, an engagement recess 72 a is formed at the distal end of the connection pipe 72 to engage and disengage the engagement claw 94 of the operation knob 92. For this reason, the suction port body 70 can be connected to the extension pipe 30 by fitting the connection pipe 72 to the inner pipe end member 51 and engaging the engagement claw 94 into the engagement recess 72 a. . When the suction port body 70 is removed from the extension pipe 30, the operation knob 92 is pushed against the urging force of the spring 95 by the fingertip to disengage the engagement claw 94 from the engagement recess 72a. This is done by pulling out from the inner tube 50.
[0056]
As described above, the inner pipe 50 of the extension pipe 30 has the inner pipe end member 51 made of a synthetic resin, and the fitting state of the connection pipe 72 with respect to the inner pipe end member 51 is held by the fixing means 90. Yes. For this reason, it can be held constant so that the fitting state does not become strong regardless of the force applied from the handle portion 23 obliquely downward toward the floor surface during cleaning, and the connection pin of the connection pipe 72 and the inner pipe end member 51. It is easy to guarantee the reliability of the electrical connection with the connection piece 54a. On the other hand, when the inner pipe end member 51 and the connection pipe 72 are connected by taper fitting, the fitting is strengthened by the oblique downward force, and the connection pipe 72 is connected from the inner pipe end member 51. Since the connection between the connection pin of the connection pipe 72 and the connection piece 54a of the inner pipe end member 51 is easily stressed, there is a possibility that a stable electrical connection cannot be guaranteed over a long period of use. Since the inner pipe end member 51 is made of synthetic resin, the fixing means 90 can be easily provided there, and the electrical connection between the connection pin of the connection pipe 72 and the connection piece 54a of the inner pipe end member 51 is achieved. Can be easily and reliably insulated.
[0057]
In addition, the extension pipe 30 is electrically conductive in the storage portion 31 formed by isolating the electrical connection between the outer pipe 40 and the inner pipe 50 accompanying the expansion and contraction from the pipe inner passage through which the dust-containing air of the outer pipe 40 passes. Since the operation is performed via the rail 47 and the sliding contact piece 56 that slides on the rail 47, the sliding portion is not exposed to an air flow containing dust during cleaning. For this reason, poor conduction due to dust contained in the airflow can be reliably prevented. In addition, the electric wire 54 to which the sliding contact piece 56 is connected is covered with the synthetic resin wire cover 53 of the inner tube 50 and the storage portion 31 is also surrounded by the synthetic resin material. The electrical insulation performance with respect to the conductive path extending across the tube 50 is excellent.
[0058]
The present invention is not limited to the one embodiment. For example, the outer tube main body 41 and the cover 42 can be made of metal. In addition, the present invention can be applied to a vacuum cleaner other than a canister as long as the vacuum cleaner includes a two-stage extendable extension pipe.
[0059]
【The invention's effect】
According to the present invention, it is possible to provide an extension pipe capable of ensuring a necessary and sufficient size of the pipe passage while suppressing an increase in thickness, and a vacuum cleaner including the extension pipe.
[Brief description of the drawings]
FIG. 1 is a perspective view of a canister-type vacuum cleaner according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view showing a part of the extension pipe provided in the vacuum cleaner of FIG.
3 is a cross-sectional view showing a connection relationship between the extension pipe of FIG. 2 and the connection pipe of the suction port body in a contracted state. FIG.
4 is a cross-sectional view of the extension tube along the line AA in FIG. 3;
5 is an exploded perspective view showing the extension tube of FIG. 2; FIG.
6 is a perspective view showing the extension tube of FIG. 2 in a state where the inner tube and the outer tube are separated from each other. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Electric vacuum cleaner, 2 ... Vacuum cleaner main body, 16 ... Electric blower, 17 ... Dust collection part filter, 20 ... Dust collection hose, 30 ... Extension pipe, 31 ... Storage part, 40 ... Outer pipe, 41 ... Outer pipe main body 42 ... Cover, 47 ... Conductive rail, 47a ... Connection pin (first terminal), 51 ... Inner tube end member, 52 ... Inner tube main body, 53 ... Electric wire cover, 54 ... Electric wire, 56 ... Sliding contact piece (second Terminal), 58 ... cover main body, 59 ... cover back cover, 71 ... suction port body main body, 72 ... connection pipe, 73 ... rotating cleaning body, 74 ... electric motor

Claims (3)

An extension pipe having an outer pipe and an inner pipe combined in a stretchable manner to guide a dust-containing air flow, wherein the inner pipe is movably inserted into the outer pipe, and the inner pipe main body. An extension pipe comprising an inner pipe end member made of synthetic resin connected to one end of the main body and protruding from one end of the outer pipe. The extension pipe according to claim 1,
The outer tube has a storage portion extending in the axial direction of the outer tube, and a first terminal is provided at the other end portion of the outer tube, and is electrically connected to the first terminal to be axially connected to the outer tube. A conductive rail extending to the storage portion is provided,
The inner pipe has an electric wire cover that is connected to the inner pipe end member and extends in the axial direction of the inner pipe and is movably inserted into the storage portion, and the electric pipe cover is slidably contacted with the conductive rail. A contact piece is attached, a second terminal is provided on the inner tube end member, and an electric wire having both ends electrically connected to the second terminal and the sliding contact piece is incorporated in the wire cover. ing. The operation of the electric blower in the main body of the vacuum cleaner causes the dust on the surface to be cleaned from the suction port which is communicated to the dust collecting part of the main body of the vacuum cleaner via the dust suction hose and the extension pipe and is moved along the surface to be cleaned. A vacuum cleaner that uses the extension pipe according to claim 1 or 2 as the extension pipe in the vacuum cleaner that sucks in and collects the sucked dust in the dust collecting portion.

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