JP4009137B2 - Recoil starter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention rotates a rope reel by pulling a recoil rope wound around the rope reel, and transmits the rotation of the rope reel to a drive pulley connected to the engine side via a one-way rotation mechanism such as a centrifugal ratchet. The present invention also relates to a recoil starter that starts the engine by the rotation of the drive pulley.
[0002]
[Prior art]
The rotation of the rope reel rotated by pulling the recoil rope is transmitted to the cam, and the drive pulley on the engine side is rotated via a one-way rotation mechanism such as a centrifugal ratchet engaged with and disengaged from the cam. In the recoil starter, a damper spring is interposed between the front rope reel and the cam and both are elastically connected to transmit the rotation of the rope reel to the cam via the damper spring. A horizontal recoil starter capable of absorbing a shock transmitted to a hand due to a fluctuation or the like is known from Japanese Utility Model Laid-Open No. 2-149872.
[0003]
[Problems to be solved by the invention]
In the above prior art, the damper spring is disposed on the outer peripheral surface of the rope reel and the cam, one end of the damper spring is bent in the radial direction and engaged with the rope reel, and the other end is bent in the axial direction. And is fitted into an opening formed in the cam. Since the damper spring is attached in a free state between the rope reel and the cam, the damper spring vibrates with respect to the rope reel and the cam due to the vibration of the driving engine after the engine is started. In general, parts such as rope reels and cams are made of a plastic material for cost and weight reduction, and wears the engaging part of the rope reel and the opening of the cam that are always in contact with the damper spring, and the damper spring. There is a problem that the play in the rotational direction may occur between the rope reel and the cam and the function at the time of starting the engine is deteriorated.
[0004]
The present invention solves the above-described problems of the prior art, suppresses vibration of the damper spring due to vibration during engine driving, and functions at the time of engine start operation due to wear of cams, rope reels, etc. formed of plastic material It is an object to prevent the decrease and improve the durability of the coil starter.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, the recoil starter of the present invention is a recoil starter for starting the engine by transmitting the rotation on the drive unit side rotated by the pulling of the recoil rope to the drive pulley on the engine side via the centrifugal ratchet. The drive unit includes a rope reel wound with a recoil rope and a cam that transmits rotation to a drive pulley on the engine side via a centrifugal ratchet, and an annular recess is opposed to the joint surface of the rope reel and the joint surface of the cam, respectively. The damper spring is accommodated in the annular recess, and both ends of the damper spring are locked to the rope reel and the cam, respectively, and the rope reel and the cam are rotationally connected via the damper spring. What annular recess the winding outer diameter formed on the rope reel or the cam in a free state And somewhat larger than the diameter of the peripheral wall surface of Kano outside the damper spring is brought into close contact with the outer peripheral wall surface of one of the annular recess of the rope reel or cam, characterized in that is housed.
[0006]
According to a second aspect of the present invention, there is provided a recoil starter for starting the engine by transmitting rotation on the drive unit side driven by pulling of the recoil rope to a drive pulley on the engine side through a centrifugal ratchet. A rope reel wound with a rope and a cam that transmits rotation to a drive pulley on the engine side via a centrifugal ratchet, and an annular recess is formed on each of the joint surface of the rope reel and the joint surface of the cam, with accommodating the damper spring are engaged thereby locked to both ends of the damper spring to the rope reel and the cam to rotate connecting the rope reel and the cam through a damper spring in said annular recess, said free length of the damper spring larger set than the length between the bottom surface of each of the annular recess formed in the rope reel and the cam, the damper Characterized in that the pulling was housed in a compressed state between the bottom surface of the annular recess.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described based on examples shown in the drawings. As shown in FIG. 1, the recoil starter of the present invention pulls the handle 3 coupled to the end of the recoil rope 2 exposed to the outside of the case 1, thereby driving the drive unit accommodated in the case 1. Is rotated, and the engine is started by rotating the crankshaft of the engine by the rotation of the drive unit.
[0008]
As shown in FIGS. 2 to 4, the rope reel 4 around which the recoil rope 2, one end of which is drawn out of the case 1, is rotatable about a reel support shaft 5 that is formed to protrude inside the case 1. The one end side of the recoil rope 2 wound around the rope reel 4 is fixed to the rope reel 4, and the other end of the recoil rope 2 is pulled out to the outside of the case 1, A handle 3 for manually pulling the recoil rope 2 is coupled. By pulling the handle 3, the recoil rope 2 is pulled out from the rope reel 4, and the rope reel 4 is driven to rotate about the reel support shaft 5.
[0009]
Between the side surface of the rope reel 4 and the inner wall surface of the case 1, the rope reel 4 rotated by pulling the recoil rope 2 is rotated in the reverse direction, and the drawn recoil rope 2 is wound around the rope reel 4. A recoil spring 6 for returning is disposed. One end side of the inner periphery side of the recoil spring 6 is fixed to the case 1 and the other end portion of the outer periphery side is fixed to the rope reel 4. When the rope reel 4 is rotated by pulling the recoil rope 2, the recoil spring 4 is rotated. The rotational force is stored in the recoil spring 6, and the rope reel 4 is rotated in the reverse direction with the rotational force stored in the recoil spring 6 by releasing the recoil rope 2, and the recoil rope 2 is rewound onto the rope reel 4. Operates as follows.
[0010]
A cam support shaft 7 is formed concentrically on the inner side of the reel support shaft 5 formed in the case 1, and the cam supports the rotation of the rope reel 4 to the crank shaft side on the engine side. 8 is rotatably supported. The cam 8 is formed with a cam claw 11 which is engaged with and disengaged from a centrifugal ratchet 10 formed on a drive pulley 9 connected to a crankshaft of the engine in the circumferential direction. By engaging with the ratchet 10, the rotation on the cam 8 side is transmitted to the crankshaft of the engine via the drive pulley 9. After the engine is started, the drive pulley 9 is rotated by the engine, so that the centrifugal ratchet 10 is rotated in a direction away from the cam claw 11 by centrifugal force, and the rotation transmission between the engine side and the cam 8 side is cut off. Is done.
[0011]
Annular recesses 12 and 13 are formed on opposite sides of the rope reel 4 and the cam 8 so as to face each other, and the rope reel 4 and the cam 8 are rotationally connected in the annular recesses 12 and 13. A damper spring 14 is accommodated. As shown in FIG. 5, the damper spring 14 is formed in the shape of a torsion coil spring, and a locking end 15 obtained by bending the end bent in the horizontal direction into a U-shape is formed on one end of the damper spring 14. Is formed. The locking end 15 is accommodated in a locking groove 16 formed continuously with the annular recess 12 on the outer peripheral side of the annular recess 12 of the rope reel 4 so that the rope reel 4 and the damper spring 14 rotate in the rotational direction. Connected to A locking end 17 bent in the axial direction is formed on the other end side of the damper spring 14, and the locking end 17 extends from the groove bottom of the annular recess 13 of the cam 8 to the cam 8. The other end side of the damper spring 14 is rotationally connected to the cam 8 by being inserted into a locking hole 18 formed so as to penetrate the upper surface side.
[0012]
As shown in FIG. 2, the diameter of the outer peripheral wall surface 19 of the annular recess 12 formed in the rope reel 4 is slightly smaller than the diameter of the outer peripheral wall surface 20 of the annular recess 13 formed in the cam 8. Further, the outer diameter of the damper spring 14 in a free state is formed so as to be larger than the diameter of the outer peripheral wall surface 19 of the annular recess 12 of the rope reel 4. When assembling the damper spring 14 in the annular recess 12 of the rope reel 4, the other end side of the damper spring 14 is placed along the winding direction while the locking end 15 on one end side of the damper spring 14 is accommodated in the locking groove 16. By rotating, the winding diameter of the damper spring 14 is reduced and fitted into the annular recess 12. As a result, the damper spring 14 is accommodated elastically in close contact with the outer peripheral wall surface of the annular recess 12.
[0013]
The cam 8 is assembled to the cam spindle 7 so that the locking end 17 formed on the other end side of the damper spring 14 is inserted into the locking hole 18 formed in the cam 8, and the tip of the cam spindle 7 is A screw 22 is fastened to the portion via a restraining plate 21, and the cam 8 and the rope reel 4 can be rotated by the restraining plate 21 so that the annular recesses 12 and 13 face each other via the cam 8. As a result, the cam 8 is rotated via the damper spring 14 in the forward direction and the reverse direction as the rope reel 4 rotates.
[0014]
Next, the operation of the recoil starter of the above embodiment will be described. Before the engine starting operation, the centrifugal ratchet 10 formed on the drive pulley 9 connected to the crankshaft of the engine is in the state of being moved inward by the action of the spring, and the cam claw 11 formed on the cam 8 It is arranged at the position where it touches. When the recoil rope 2 is pulled, the rope reel 4 is rotated, and the cam 8 is rotated via the damper spring 14 integrally therewith. The cam claw 11 of the cam 8 contacts the centrifugal ratchet 10 to rotate the drive pulley 9 via the centrifugal ratchet 10 and the crankshaft connected to the drive pulley 9 is rotated. As a result, the rotational load increases and the load on the cam 8 increases, but the damper spring 14 is twisted to absorb this load, so that no impact is directly transmitted to the recoil rope 2 side. At the same time, the rotational force on the rope reel 4 side is stored in the damper spring 14. At this time, the damper spring 14 is twisted so that the outer diameter of the winding is reduced and is separated from the peripheral wall of the concave portion of the rope reel 4, but is elastically held between the rope reel 4 and the cam 8 by the locking end portions 15 and 17 at both ends. Has been.
[0015]
Further, when the rope reel 4 is rotated and the rotational force exceeds the starting resistance of the engine, the rotational force of the rope reel 4 caused by the pulling of the recoil rope 2 and the rotational force stored in the damper spring 14 are released to the cam 8 side. Since the torque is transmitted to the drive pulley 9 via the centrifugal ratchet 10, the crankshaft is rotated at once and the engine is started. At this time, the damper spring 14 whose diameter has been reduced returns to its original diameter and is brought into close contact with the peripheral wall surface 19 of the annular recess 12 of the rope reel 4. When the engine is started and the crankshaft is rotated, the centrifugal ratchet 10 is rotated outward by the action of centrifugal force and does not come into contact with the cam claw 11 of the cam 8. When the recoil rope 2 is loosened after the engine is started, the rope reel 4 is rotated in the reverse direction by the rotational force accumulated in the recoil spring 6, and the recoil rope 2 is rewound onto the rope reel 4.
[0016]
At this time, the cam 8 is rotated in the reverse direction integrally with the rope reel 4 via the damper spring 14, but after the engine is started, the centrifugal ratchet 10 is rotated outward as described above. The eight cam claws 11 can rotate without contacting the centrifugal ratchet 10. In the rare event that the engine does not start with a single operation, the cam 8 rotates in the reverse direction via the damper spring 14 together with the rope reel 4 when the recoil rope 2 is returned for re-operation. 8 cam claws 11 abut on the back side of the centrifugal ratchet 10 and rotate the centrifugal ratchet 10 outward against the biasing force of the spring, so that the cam 8 and the rope reel 4 are prevented from rotating in the reverse direction. There is no.
[0017]
When the engine is started, vibrations during operation of the engine are propagated to the recoil starter. However, the damper spring 14 is elastically adhered and accommodated in the peripheral wall surface 19 in the annular recess 12 formed in the rope reel 4. Therefore, relative vibration between the damper spring 14 and the rope reel 4 or the cam 8 does not occur, and wear of the locking groove 16 and the locking hole 18 due to vibration of the damper spring 14 can be prevented. . Therefore, even if the components such as the rope reel 4 and the cam 8 are formed of a plastic material, sufficient durability can be exhibited.
[0018]
FIG. 6 shows a recoil starter according to another embodiment. In this embodiment, the diameter of the outer peripheral wall surface 20 of the annular recess 13 formed on the cam 8 side is set to the diameter of the peripheral wall surface 19 of the annular recess 12 of the lobe reel 4. The damper spring 14 is accommodated in close contact with the peripheral wall surface 20 of the annular recess 13 of the cam 8. FIG. 7 shows still another embodiment. In this embodiment, the free length of the damper spring 14 is the length between the bottom surfaces 23 and 24 of the annular recesses 12 and 13 formed in the rope reel 4 and the cam 8. The damper spring 14 is accommodated in a compressed state between the bottom surfaces 23 and 24 in the annular recesses 12 and 13. According to these embodiments, the vibration of the damper spring 14 can be effectively prevented and the wear of the engaging portion between the rope reel 4 and the cam 8 can be prevented.
[0019]
【The invention's effect】
As described above, according to the present invention, the damper spring is interposed between the rope reel around which the recoil rope is wound and the cam that transmits the rotation of the rope reel to the crankshaft side of the engine. The damper spring is brought into close contact with the peripheral wall surface of the annular recess using the elasticity of the damper spring on the reel or cam side, or is housed in a compressed state between the bottom surfaces. Without vibration in the annular recess, it is possible to prevent wear of the rope reel and cam locking groove and the locking hole formed of plastic material, and it is possible to prevent deterioration of the function at the start operation due to backlash due to wear. The durability of the recoil starter can be improved.
[Brief description of the drawings]
1 is a front view of a recoil starter according to an embodiment of the present invention. FIG. 2 is a longitudinal side view of the same recoil starter as in FIG. 1. FIG. 3 is a rear view of the recoil starter as in FIG. FIG. 5 is a rear view of the recoil starter with the driving pulley removed. FIG. 5 is a perspective view of the rope reel, damper spring and cam of the embodiment of FIG. 1. FIG. 6 shows the main part of the recoil starter according to another embodiment of the present invention. FIG. 7 is a cross-sectional view showing the main part of a recoil starter according to still another embodiment.
DESCRIPTION OF SYMBOLS 1 Case 4 Rope reel 8 Cam 9 Drive pulley 12 Annular recessed part 13 Annular recessed part 14 Damper spring 15 Engagement end part 16 Engagement groove 17 Engagement end part 18 Engagement hole 19 Peripheral wall surface 20 Peripheral wall surface 21 Holding plate 22 Screw 23 Bottom surface 24 Bottom

Claims (2)

In a recoil starter for starting the engine by transmitting the rotation on the drive side rotated by the pulling of the recoil rope to the drive pulley on the engine side through the centrifugal ratchet, a rope reel on which the drive unit winds the recoil rope; The engine-side drive pulley includes a cam for transmitting rotation via a centrifugal ratchet, and an annular recess is formed on the joint surface of the rope reel and the joint surface of the cam, respectively , and a damper spring is provided in the annular recess. The damper spring is housed and both ends of the damper spring are locked to the rope reel and the cam, respectively, and the rope reel and the cam are rotationally connected via the damper spring, and the winding outer diameter of the damper spring in a free state is set to the rope reel or the cam. somewhat than the diameter of one of the outer peripheral wall surface of the annular recess formed in the cam is set larger, the damper Recoil starter the pulling in close contact with the outer peripheral wall surface of one of the annular recess of the rope reel or cam, characterized in that is housed. In a recoil starter for starting the engine by transmitting the rotation on the drive side rotated by the pulling of the recoil rope to the drive pulley on the engine side through the centrifugal ratchet, a rope reel on which the drive unit winds the recoil rope; The engine-side drive pulley includes a cam for transmitting rotation via a centrifugal ratchet, and an annular recess is formed on the joint surface of the rope reel and the joint surface of the cam, respectively , and a damper spring is provided in the annular recess. The both ends of the damper spring are locked to the rope reel and the cam, respectively, and the rope reel and the cam are rotationally connected via the damper spring, and the free length of the damper spring is formed on the rope reel and the cam. It is set larger than the length between the bottom surface of each of the annular recess, the annular concave damper spring Recoil starter, characterized in that is housed in a compressed state between the bottom surface.

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