JP5637724B2 - Backpack type blower - Google Patents

Description

  The present invention relates to a backpack-type blower that is used in, for example, a blower cleaner or a chemical spreader that collects fallen leaves and garbage with a high-speed airflow.

  As can be seen in Patent Document 1 or Patent Document 2, the conventional back blower has a fan case in which an engine (including an electric motor; the same applies hereinafter) is mounted on a frame that is carried on the back of an operator. . The fan case is a hollow housing that contains a fan that rotates parallel to the back. The fan case has a circular shape following the rotation of the fan, and the front side (the side facing the back) surrounds the center of rotation of the fan. And the exhaust ports are opened in the tangential direction of the peripheral surface. The engine is supported on the back side of the fan case via an air cooling unit (a unit incorporating a small fan that takes in part of the outside air from the fan case), and the fan case and the engine are integrally covered with a cover.

  The fan case is attached to the frame leaving a gap with respect to the air intake, and sucks outside air from the air intake according to the rotation of the fan. The sucked outside air flows radially outward along the blades of the fan, forms a swirl flow along the circulating inner surface, travels toward the exhaust port, and is injected from the exhaust port through the injection nozzle through the flexible pipe. . The engine is air-cooled by taking a part of the outside air sucked from the air intake of the fan case along the continuous cover from the back side of the fan case by the action of the air cooling unit.

JP 2004-308273 A JP 09-067815 A

  The conventional back fan has a problem that the structure of the fan case changes according to the engine as a result of the structure of the back side being different depending on the engine to be installed even in the same fan case. This means that a part of the outside air that has been sucked in is sent along the cover to air-cool the engine, and, as will be described later, the fan case that supports the frame and the engine must be highly integrated. It is a restriction by etc. However, as described above, in addition to the problem that the structure of the fan case changes according to the engine, there is also a problem that all the outside air sucked from the intake port cannot be used for blowing air (decrease in engine use efficiency).

  Also, in order to take in outside air from the air intake vent, the front side of the fan case cannot be brought into contact with the operator's back, so the fan case remains in the frame that makes contact with the operator's back while leaving a gap with respect to the air intake. Had to be partially supported and attached. This means that a connection structure that stably supports the fan case and the engine (the engine is supported by the fan case) with respect to the frame is essential, which increases the overall configuration and reduces the degree of freedom in design. It was a cause. In addition, structural considerations were necessary to prevent the air intake on the back side of the fan case from sucking the clothes and hair of workers.

  Therefore, in the back blower, the cooling of the engine is not impaired, and the efficiency of the engine is increased, so that it is not necessary to change the structure of the fan case depending on the engine. In order to increase the degree of freedom in design, we focused on the relationship between the fan case and the engine.

As a result of the study, a fan blower that carries a fan case with a built-in fan and an engine that rotates the fan on the back of the fan case, the fan case has a suction port at a position surrounding the rotation center of the fan on the back support surface. each exhaust port in the tangential direction of the circumferential surface opened, before Symbol opens a through opening axis coincides with the rotation center of the fan, contacting surface or fitting the mounting plate is projected the rotation shaft of the engine to the support surface solid constant is engaged, by mounting the fan to a rotating shaft which projects into the interior of the fan case from the through-opening, leaving a gap relative to the inlet, to support the engine to the support surface through the attachment plate Te becomes, by freely exchanging a mounting plate which was the same the contact surface relationship or fitting relationship with the support surface is the knapsack blower can freely change the combination of the fan case and engine

  The back blower of the present invention opens on the back side (opposite side to the back) of the fan case, and sucks outside air from an air inlet having a gap with respect to the engine, and the engine in the vicinity of the rotating shaft mainly flows the outside air. Is cooled by air. In this case, since it is not necessary to guide part of the outside air from the fan for air cooling, the engine can be easily air-cooled by being exposed to the outside without covering the engine. Since all the outside air that has been sucked is sent to the exhaust port, the amount of air blown from the injection nozzle can be increased even if the same engine is used with the same output.

As described above, the engine does not need to be covered with a cover continuous from the fan case, and is supported by the fan case only by fixing the attachment plate in contact with or fitting to the support surface. Now, by freely replace the support surface and the mounting plate and the preparative with plate with the same the contact surface relationship or engagement relationship can freely change the combination of the fan case and engine. Since the fan case is usually a resin member, a support surface having the same specification may be integrally formed even if the shape or size changes. In the engine, the mounting plate holding the bearing that supports the rotating shaft may be exchangeable.

  The carrying type blower of the present invention can cool the engine by the outside air sucked from the intake port, and the effect that the utilization efficiency of the engine can be improved by sending all the sucked outside air to the exhaust port is obtained. . And since the fan case does not require a frame because the front side can be brought into contact with the back of the operator (actually a cushion sheet or the like is interposed), the increase in the overall configuration is suppressed, Moreover, the freedom degree of design can be raised. In addition, since the air inlet is on the back side of the fan case, there is an advantage that it is unnecessary to consider the structure so as not to suck the clothes and hair of the worker.

Further, knapsack blower of the present invention, by freely exchange preparative with plates, a combination of a fan case and the engine becomes free, it becomes possible to configure the fan case separately from the engine. If you turn it over, you can use engines with different specifications while using the same fan case. This brings about an effect of reducing the manufacturing cost and the management cost due to the common use of parts, and improving the convenience of allowing only the engine to be replaced with an existing fan case, for example.

It is a front-back direction partial sectional view in an example of a backpack type blower to which the present invention is applied. It is a rear view of the backpack type air blower of this example. FIG. 3 is a rear view corresponding to FIG. 2 and illustrating an engine of a backpack type blower of this example. It is a front view of only the engine of the backpack type blower of this example. It is a perspective view showing the fan in the backpack type air blower of this example, the back side member of a fan case, and a protection net.

  An embodiment for carrying out the present invention will be described with reference to the drawings. As shown in FIGS. 1 to 3 (all belts, cushion pads, etc. are not shown), the fan case 1 and the engine 2 are arranged in the same order as in the prior art. 1 is different from the prior art in that an intake port 123 for taking in outside air is provided on the back side and the engine 2 is supported by the fan case 1 leaving a gap with respect to the intake port 123. For this reason, since it is not necessary to form a gap with respect to the operator's back on the front side of the fan case 1, the frame is omitted, and the front side of the fan case 1 having a flat copy surface is brought into contact with the operator's back. (Actually, a cushion pad is attached to the front side of the fan case 1, but the cushion pad is not shown in FIG. 1).

  The fan case 1 has the same configuration as that of the conventional type, that is, a resin-made hollow housing with a fan 3 that rotates in parallel with the back, and the front view shape (= rear view shape) has a circular shape following the rotation of the fan. The front side member 11 and the back side member 12 that are divided in the front and rear directions are integrated by bolts with the fan 3 built-in. The front side member 11 is provided with a plurality of reinforcing ribs extending vertically and horizontally on the front side to increase the rigidity as a member and to flatten the copying plane including the front edge of the reinforcing rib so as to contact the operator's back. . The exhaust port 13 protrudes in a tangential direction of the peripheral surface (in this example, diagonally downward to the right when viewed from the back, see FIGS. 2 and 3), and is divided into a front side member 11 and a back side member 12 respectively. A part is formed. For example, a flexible pipe (not shown) is connected to the exhaust port 13 via a connection adapter 131.

  As shown in FIG. 4, the air inlet 123 is a gap between a plurality of support ribs 121 projecting radially inward from the inner periphery of the circular opening provided in the back side member 12 at equal intervals in the circumferential direction. It is in a position surrounding the rotation center of the fan 3. More specifically, the air inlet 123 is opened at a position corresponding to a curved plate provided inside the twisted blade 31 of the fan 3 in the radial direction. The support rib 121 supports a circular support surface 122 that includes a rotation center of the fan 3 and has a circular shape when viewed from the back. The support surface 122 opens a through opening 124 whose axis coincides with the rotation center of the fan 3. The engine 2 is supported by the support surface 122 by causing the mounting plate 22 from which the rotating shaft 21 protrudes to come into contact with the support surface 122 and fixed by bolting. The support surface 122 and the mounting plate 22 are specified in a positional relationship in which they are assembled by fitting a pair of positioning protrusions 125 and positioning hole portions 222 provided at four locations on the 0 degree and 90 degree diagonal lines. The positioning projection 125 protrudes through a through hole provided in the inner peripheral annular plate 141 of the protective net 14 and fits into the positioning hole 222 of the mounting plate 22.

  The fan case 1 of this example covers all the intake ports 123 with an annular protective net 14 in order to prevent foreign matter from entering from the intake ports 123 and to prevent the operator from pushing their fingers. Yes. The protective net 14 is an integrally molded product made of resin in which a net is formed between an inner peripheral annular plate 141 that contacts the outer peripheral edge of the support surface 122 and an outer peripheral annular plate 142 that contacts the cover 4 from the inside. The inner peripheral annular plate 141 is sandwiched between the outer peripheral edge of the support surface 122 and the outer peripheral edge of the mounting plate 22 to be fixed. The positional relationship of the protective net 14 with respect to the support surface 122 is specified by the engagement of the annular convex portion 126 of the support surface 122 and the notched concave portion 143 of the inner peripheral annular plate 141 provided at four locations on 45 ° and 135 ° diagonal lines. . Instead of the protective net 14 of this example, for example, a net formed integrally with the support rib 121 may be used, or conversely, a metal or resin net made integral with the mounting plate 22 may be used.

  The engine 2 has a mounting plate 22 mounted on the front side that is circular in a rear view and has a size corresponding to the support surface 122 that supports a rotating shaft 21 connected to an output shaft (not shown) by a bearing 221. As described above, the rotating shaft 21 protrudes into the fan case 1 from the through opening 124 of the support surface 122 with which the mounting plate 22 is in contact, and the fan 3 is mounted. The mounting plate 22 is fixed in contact with the support surface 122, so that the mounting plate 22 functions as a support member for stably supporting the engine 2 to the fan case 1, and the structure with respect to the support surface 122 is matched. It also functions as an attachment adapter that allows the engine 2 to be attached to the same fan case 1. From this point, the mounting plate 22 as the mounting adapter may be fitted to the support surface 122 by a fitting relationship as well as a contact surface relationship as in this example.

  The fan 3 is an impeller that sucks in air from the axial direction and exhausts it in the radial direction. A large number of twisted blades 31 are provided on the side surface of the truncated cone-shaped body 32 having a concave curved side surface on the back side, and A matched hollow insertion shaft 33 is integrally provided. The torsional blade 31 in the fan 3 of this example is formed of a three-dimensional curved surface having a different cross-sectional shape inside and outside the radius. The outer side in the radial direction of the twisted blade 31 is a flat plate extending parallel to the axial direction and extending in the radial direction so that the outside air can be easily guided toward the inner peripheral surface (outer side in the radial direction) of the fan case 1. Is a curved plate that protrudes in the axial direction compared to the outside in the radial direction and is inclined toward the upstream in the rotational direction, thereby making it easy to take in outside air. In the fan 3 of this example, a wedge piece 212 is press-fitted between the six-section sectional recess 331 of the insertion shaft 33 into which the rotation shaft 21 is inserted and a plane formed at a point-symmetrical position of the rotation shaft 21 to the rotation shaft 21. An idling nut 211 is screwed onto a male screw at the tip of the rotating shaft 21 protruding from the end of the insertion shaft 33 to prevent idling, and the rotating shaft 21 is mounted.

  The backpack type blower of this example covers the fan case 1 with the cover 4, and forms a handle 41 by forming a space penetrating in the front and rear at the upper edge of the cover 4, projecting downward and projecting horizontally. A stand 42 having legs is attached to the lower edge. The stand 42 is a separate member from the cover 4 and is attached by being externally fitted to an attachment projection (not shown) protruding downward from the lower edge of the cover 4. Since the backpack type blower of the present invention does not need to guide outside air toward the engine 2, it is not necessary to cover the engine 2 with a cover. Further, the frame is omitted because there is no possibility that the operator's back may block the air intake. The cover 4 covering the fan case 1 is a member provided with a grip 41 and a stand 42 instead of the omitted frame.

  The cover 4 of the present example is a resin box having a substantially rectangular outer shape in a rear view that is large enough to wrap the fan case 1 except for the circular opening including the air inlet 123 and the support surface 122 other than the front side that contacts the operator's back. In addition to being directly screwed to the back side member 12 of the fan case 1, the pin is engaged with the outer peripheral annular plate 142 of the protective net 14 (see FIG. 1) to fix the position. Since the cover 4 is sized to enclose the fan case 1, it has a function of protecting the fan case 1 and a function of determining the design of the entire apparatus in place of the fan case 1. This means that the external appearance of the entire apparatus can be changed by changing the external shape of the cover 4. For example, the position or shape of the grip 41, the external shape of the stand 42, or the stand 42 can be changed. The design of the back blower can be changed by changing the mounting position.

1 Fan case
11 Front side member
12 Rear side member
121 Support rib
122 Support surface
123 Air intake
13 Exhaust port
14 Protective net 2 Engine
21 Rotation axis
22 Mounting plate 3 Fan 4 Cover

Claims (1)

In a shoulder-type blower that carries a fan case with a built-in fan and an engine that rotates the fan,
The fan case has an air intake opening at the position surrounding the rotation center of the fan at the support surface on the back side and an air exhaust opening in the tangential direction of the peripheral surface .
Opening a through opening axial to the rotation center of the front Symbol fans are matched, and fixed by a mounting plate which is protruded to the axis of rotation of the engine causes surface contact or fitted to said supporting surface, from the through-opening of the fan case By attaching a fan to the rotating shaft protruding inside, leaving a gap with respect to the intake port, the engine is supported on the support surface via the mounting plate ,
A backpack type blower characterized in that the combination of the fan case and the engine can be freely changed by making the mounting plate having the same contact surface relationship or fitting relationship with the support surface interchangeable .

Images