WO2019187113A1

WO2019187113A1 - Engine

Info

Publication number: WO2019187113A1
Application number: PCT/JP2018/013888
Authority: WO
Inventors: 小林　哲也; 泰則松原
Original assignee: 本田技研工業株式会社
Priority date: 2018-03-30
Filing date: 2018-03-30
Publication date: 2019-10-03
Also published as: DE112018007401T5; DE112018007401B4

Abstract

An engine (E) is provided with: an engine body (1); and a top cover (4) that covers the engine body (1), wherein at least a pair of engaging claws (45) are provided to lateral walls (42), on both sides, of the top cover (4) so as to extend downward, and a pair of engaging holes (31) with which the engaging claws (45) engage are provided to the engine body (1) side. Each of the engaging claws (45) is provided with a plate section (451) that is provided so as to extend downward, and a bulging section (452) that is provided to the leading end of the plate section (451) and that bulges inward from the plate section (451), and the bulging section (452) engages with the bottom surface (312b) of an inner wall section (312) of the corresponding engaging hole (31).

Description

engine

The present invention relates to an engine that can be mounted on a working machine such as a lawn mower or a high pressure washer.

An engine including an engine body and a top cover that covers the engine body is known. For example, the engine described in Patent Document 1 includes a vertical engine body that is mounted on a lawn mower and rotates a blade (cutting blade), and a top cover that covers the engine body.

Japanese National Utility Model Publication No. 02-137506

However, since the top cover described in Patent Document 1 is attached to the engine main body via bolts and nuts, it takes time to attach and detach, and there is a possibility that the maintenance performance of the engine is lowered. Therefore, it is conceivable to attach the top cover by engaging it with the engine body via the engaging claw, but in the case of attachment by engagement, when an external force such as an object hitting the top cover is applied, There is a possibility that the engagement of the engaging claws is released and the top cover is detached.

The present invention provides an engine capable of preventing the top cover from being detached from the engine body by preventing the engagement of the engagement claws from being released by an unintended external force.

The present invention
The engine body,
A top cover that covers the engine body,
The top cover has at least a pair of engaging claws extending downward on the side walls on both sides,
On the engine body side, a pair of engagement holes for engaging the pair of engagement claws are provided,
Each engaging claw
A plate portion extending downward;
A bulging portion provided at a distal end portion of the plate portion and bulging inward from the plate portion, and the bulging portion engages with a bottom surface of an inner wall portion of the engagement hole portion.

According to the present invention, even when an external force such as an object hitting the side wall of the top cover acts, the external force acts in the direction in which the engaging claw engages with the inner wall portion, so that the top cover can be prevented from coming off.

It is sectional drawing of the engine of one Embodiment of this invention. It is the perspective view which looked at the engine which removed the top cover from diagonally forward upper direction. It is a bottom view of a top cover and a recoil cover. FIG. 4 is a cross-sectional view taken along line AA in FIG. 3. FIG. 4 is a sectional view taken along line BB in FIG. 3.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. The engine E according to the present embodiment is a small general-purpose engine mounted on a walking lawnmower or the like, and includes an OHV vertical engine as the engine body 1. In this specification and the like, the axis direction of the crankshaft 9 is perpendicular to the vertical direction and the vertical direction, and the direction in which the piston 11 reciprocates is perpendicular to the front-rear direction, the vertical direction, and the front-rear direction in order to simplify and clarify the description. The direction to perform is defined as the left-right direction, and in the drawing, the front of the engine E is Fr, the rear is Rr, the left is L, the right is R, the upper is U, and the lower is D.

[engine]
As shown in FIGS. 1 and 2, the engine E of the present embodiment covers the engine main body 1, a recoil starter 2 that is disposed above the engine main body 1 and starts the engine main body 1, and covers the recoil starter 2. The recoil cover 3, the top cover 4 that covers the upper part of the engine E, the fuel tank 5 that stores the fuel of the engine body 1, the air cleaner 6 that purifies the intake air of the engine body 1, and the exhaust of the engine body 1 are silenced A muffler 7 to be discharged.

[Engine body]
As shown in FIG. 1, the engine body 1 includes an engine block 8 having a crankcase portion 8a and a cylinder portion 8b, a crankshaft 9 rotatably supported by the crankcase portion 8a in the vertical direction, and a cylinder portion. A piston 11 slidably fitted to 8b and connected to the crankshaft 9 via a connecting rod 10, an intake valve 12, an exhaust valve 13 and a spark plug 14 provided on the head portion 8c of the cylinder portion 8b; A head cover 15 that covers the head portion 8 c of the portion 8 b, a valve mechanism 16 that operates the intake valve 12 and the exhaust valve 13 according to the rotation of the crankshaft 9, and a flywheel 17 that is connected to the upper end portion of the crankshaft 9 .

[Top cover]
As shown in FIGS. 1 to 5, the top cover 4 is a resin part that allows some elastic deformation. The top cover body 41 covers the engine body 1 and the recoil starter 2 from above, and the top cover body 41. A pair of side walls 42 extending downward from both left and right end portions of the top cover body 41, a front wall 43 extending downward from the front end portion of the top cover body 41, and a rear wall 44 extending downward from the rear end portion of the top cover body 41. The top cover main body 41 of the present embodiment has a shape in which the central portion is curved upward, but may be a flat shape. Further, at the rear end portion of the top cover body 41 of the present embodiment, a hole 41 a for exposing the fuel filler port 51 of the fuel tank 5 to the upper side of the top cover 4 and the handle 21 of the recoil starter 2 are provided on the top cover 4. Holes 41b for leading upward are formed, but the presence or absence of these can be changed as appropriate.

The top cover 4 is detachably attached to the engine body 1 side in an engaged state. Hereinafter, the mounting structure of the top cover 4 will be described with reference to FIGS.

[Engaging claw]
On the left and right side walls 42 of the top cover 4, at least a pair of engaging claws 45 are extended downward. The top cover 4 of the present embodiment includes two pairs of engagement claws 45 arranged in the front-rear direction, that is, a total of four engagement claws 45, but the engagement claws 45 may be a pair or three or more pairs. Also good.

Each engagement claw 45 is provided at a plate portion 451 extending downward and a tip portion of the plate portion 451, and bulges inward (in a direction approaching the other engagement claw 45) from the plate portion 451. A bulging portion 452.

The plate portion 451 has a plate thickness direction in the left-right direction and is allowed to be elastically deformed in the left-right direction. The plate portions 451 of the pair of engaging claws 45 have their inner side surfaces 451a facing each other with a predetermined interval W1. The bulging portion 452 includes a substantially horizontal upper surface 452a along the left-right direction and the front-rear direction, and an inclined surface 452b inclined outward as it goes downward.

[Engagement hole]
The recoil cover 3 is provided with two pairs of engagement holes 31 that engage with the two pairs of engagement claws 45. Each engagement hole portion 31 extends in the vertical direction, and includes an insertion hole 311 into which the engagement claw 45 is inserted from above, an inner wall portion 312 defining an inner end of the insertion hole 311, and an outer end of the insertion hole 311. And an outer wall portion 313 that defines

The inner wall portion 312 of the pair of engaging hole portions 31 has an interval W2 between the outer side surfaces 312a substantially equal to the interval W1 described above, and a bulging portion 452 (upper surface 452a) of the engaging claw 45. A bottom surface 312b to be engaged is provided. In addition, an inclined surface 313a is provided at the upper end portion of the outer wall portion 313. The inclined surface 313a is inclined inward as it goes downward.

[Elastic member]
An elastic member 18 is provided between the recoil cover 3 and the top cover 4. The elastic member 18 may be provided on the recoil cover 3 side, or may be provided on the top cover 4 side. The elastic member 18 is compressed between the recoil cover 3 and the top cover 4 when the top cover 4 is attached.

[Attaching the top cover]
When the top cover 4 configured as described above is attached to the engine body 1 side, the two pairs of engagement claws 45 provided on the top cover 4 are inserted into the two pairs of engagement holes 31 (insertion) provided on the recoil cover 3. The hole 311) is inserted from above. At this time, the tip of the engagement claw 45 is guided to the insertion hole 311 along the inclined surface 313a formed at the upper end of the outer wall 313 of the engagement hole 31, so that the top cover 4 can be easily attached. In addition, the engagement claw 45 can be prevented from being damaged by the engagement claw 45 riding on the outer side of the outer wall portion 313 of the engagement hole portion 31.

When the two pairs of engagement claws 45 are inserted into the two pairs of engagement hole portions 31 (insertion holes 311) from above, the inclined surfaces 452b formed on the bulging portions 452 of the engagement claws 45 become the engagement hole portions. 31 is in contact with the upper end portion of the inner wall portion 312. When the top cover 4 is pushed downward in this state, the two pairs of engaging claws 45 are expanded while being elastically deformed so that the plate portions 451 of the two pairs of engaging claws 45 are opened to the outside by being guided by the inclined surface 452b. The exit 452 enters the insertion hole 311. Further, when the top cover 4 is pushed downward and the bulging portion 452 of the engaging claw 45 gets over the inner wall portion 312 of the engaging hole portion 31, the bulging portions 452 of the two pairs of engaging claws 45 are formed on the plate portion 451. While being displaced inward by the elastic restoring force, the upper surface 452a of the bulging portion 452 is engaged with the bottom surface 312b of the inner wall portion 312 of the engagement hole portion 31 from below. Thereby, the top cover 4 is restricted from moving upward, and is attached to the engine body 1 side in the engaged state.

In addition, the top cover 4 attached in this way has a direction in which the engaging claws 45 engage with the inner wall portion 312 of the engaging hole portion 31 even when an external force such as an object hitting the side wall 42 acts. That is, the engaging claw 45 acts in the direction of moving inward, so that the top cover 4 can be prevented from coming off. In addition, an elastic member 18 is provided between the recoil cover 3 and the top cover 4. When the top cover 4 is attached, the elastic member 18 is compressed between the recoil cover 3 and the top cover 4. Therefore, the vibration of the top cover 4 can be reduced.

[Removing the top cover]
When removing the top cover 4, the engagement between the engagement claw 45 and the engagement hole 31 is released and the top cover 4 is lifted upward. In the present embodiment, since the two pairs of engaging claws 45 are provided only on the left and right side walls 42 of the top cover 4, only by elastically deforming the both side walls 42 of the top cover 4 so as to expand in the left and right direction, The engagement between the bulging portion 452 of the engaging claw 45 and the inner wall portion 312 of the engaging hole portion 31 can be released, and then the top cover 4 can be easily removed by lifting the top cover 4.

On the other hand, when the top cover 4 is lifted so that the front wall 43 and the rear wall 44 intersecting the both side walls 42 of the top cover 4 are widened, an external force is applied to the side walls 42 of the top cover 4 so as to approach the inside. In this case, the external force acts in a direction in which the engaging claw 45 engages with the inner wall portion 312, that is, in a direction in which the engaging claw 45 moves inward, so that the top cover 4 does not come off. Accordingly, it is possible to prevent the top cover 4 from coming off due to an erroneous operation.

It should be noted that the above-described embodiment can be modified, improved, etc. as appropriate.
For example, although the engagement hole 31 of the above-described embodiment is provided in the recoil cover 3 attached to the engine main body 1, the engagement hole 31 may be provided directly in the engine main body 1 or the engine main body. You may provide in components other than the recoil cover 3 attached to 1. FIG.

[Summary]
This specification describes at least the following matters. In addition, although the component etc. which respond | correspond in the above-mentioned embodiment are shown in a parenthesis, it is not limited to this.

(1) Engine body (Engine body 1);
An engine (engine E) comprising a top cover (top cover 4) covering the engine body,
The top cover has at least a pair of engaging claws (engaging claws 45) extending downwardly on both side walls (side walls 42),
On the engine body side, a pair of engagement holes (engagement holes 31) with which the pair of engagement claws are engaged are provided.
Each engaging claw
A plate portion (plate portion 451) extending downward;
A bulging portion (bulging portion 452) provided at a tip portion of the plate portion and bulging inward from the plate portion, and the bulging portion is an inner wall portion (inner wall portion 312) of the engagement hole portion. And the bottom surface (bottom surface 312b) of the engine.

According to (1), in the engaging claw of the top cover, the bulging portion that bulges inward from the plate portion engages with the bottom surface of the inner wall portion of the engaging hole portion. Accordingly, even when an external force such as an object hitting the side wall of the top cover is applied, the external force is applied in a direction in which the engaging claw engages with the inner wall portion, so that the top cover can be prevented from coming off.

(2) The engine according to (1),
The engine, wherein the at least one pair of engaging claws are provided only on side walls on both sides of the top cover.

According to (2), since the engaging claws are provided only on the side walls on both sides of the top cover, when the maintenance of the engine body is necessary, the top cover is lifted so as to widen the both side walls of the top cover. Thus, the top cover can be easily removed. On the other hand, when the top cover is lifted so as to widen the front wall and the rear wall intersecting the both side walls of the top cover, an external force is applied so that the both side walls of the top cover approach the inside. In this case, the external force acts in the direction in which the engaging claw engages with the inner wall portion, so that the top cover can be prevented from coming off. Therefore, it is possible to prevent the top cover from being removed due to an erroneous operation.

(3) The engine according to (1) or (2),
The engine is provided with an inclined surface (inclined surface 313a) inclined inward as it goes downward in an outer wall portion (outer wall portion 313) of the engagement hole portion.

According to (3), since the outer wall portion of the engagement hole portion is provided with an inclined surface that is inclined inwardly toward the lower side, when the top cover is attached to the engine body side, the tip of the engagement claw The surface is guided to the engagement hole along the inclined surface. Thereby, attachment of a top cover can be made easy. Moreover, when attaching to an engine main body side, it can prevent that an engaging claw breaks because an engaging claw rides on the outer side of the outer wall part of an engaging hole part.

(4) The engine according to any one of (1) to (3),
The pair of engagement holes are provided in a recoil cover (recoil cover 3),
An engine in which an elastic member (elastic member 18) is provided between the recoil cover and the top cover.

According to (4), since the elastic member is provided between the recoil cover and the top cover, vibration can be reduced by crushing the elastic member when attaching the top cover.

E Engine 1 Engine body 3 Recoil cover 31 Engagement hole portion 312 Inner wall portion 312b Bottom surface 313 Outer wall portion 313a Inclined surface 4 Top cover 42 Side wall 45 Engagement claw 451 Plate portion 452 Swelling portion 18 Elastic member

Claims

The engine body,
A top cover that covers the engine body,
The top cover has at least a pair of engaging claws extending downward on the side walls on both sides,
On the engine body side, a pair of engagement holes for engaging the pair of engagement claws are provided,
Each engaging claw
A plate portion extending downward;
An engine comprising: a bulging portion provided at a tip portion of the plate portion and bulging inward from the plate portion, wherein the bulging portion engages with a bottom surface of an inner wall portion of the engagement hole portion.
The engine according to claim 1,
The engine, wherein the at least one pair of engaging claws are provided only on side walls on both sides of the top cover.
The engine according to claim 1 or 2,
The engine is provided with an inclined surface that is inclined inwardly toward an outer wall portion of the engagement hole portion as it goes downward.
The engine according to any one of claims 1 to 3,
The pair of engagement holes are provided in the recoil cover,
An engine, wherein an elastic member is provided between the recoil cover and the top cover.