JP5416262B2 - Recoil starter - Google Patents

Description

  The present invention relates to a recoil starter for starting an engine by rotating a rope reel by pulling a recoil rope and transmitting the rotation of the rope reel to a drive pulley connected to a crankshaft of the engine.

  The rope reel is rotated by pulling the recoil rope wound around the rope reel, and the rotation of the cam rotated by the rotation of the rope reel is coupled to the crankshaft of the engine via a clutch mechanism such as a centrifugal clutch. In a recoil starter that is transmitted to a rotary member such as a flywheel magnet or a drive pulley and rotates the crankshaft of the engine via the rotary member to start the engine, a buffer is stored between the rope reel and the cam. By interposing a force means, the shock accumulation means prevents the shock due to a sudden load fluctuation on the engine side from being transmitted to the rope reel side, and the rotation force of the rope reel is accumulated in the buffer accumulation means. The engine can be started easily by releasing the rotational force stored in the buffer storage means. It is known to have (for example, see Patent Document 1).

The conventional mechanism includes a rope reel that is rotated by towing a recoil rope, a cam that transmits rotational force to a starting pulley that is connected to a crankshaft of an engine via a clutch mechanism, and a spring that serves as a buffer energy storage unit. And a spring case that accommodates each of the springs is rotatably supported by a support shaft formed in the case, and a one-way ratchet mechanism is formed between the rope reel and the spring case to rotate the rope reel in the engine starting direction. When the rope reel is rotated by pulling the recoil rope, the spring case is rotated integrally via the one-way ratchet mechanism, and the rotation of the rope reel is transferred to the starting pulley via the spring case. The start pulley rotates due to the engine starting resistance. The rotational force of the stop to the rope reel to the spring is to be accumulated force. Further, a one-way clutch is formed between the support shaft and the spring case to prevent the spring case from rotating in the reverse direction.
JP 2001-132591 A

  However, in the conventional recoil starter, for example, a starter case is fixed to a housing on the engine side with a bolt. In addition, each part is independent, and these are assembled one by one with screws or the like, which increases the number of assembly steps and takes time to complete.

  An object of the present invention is to provide a recoil starter that solves the above-described problems, facilitates assembly of components, and reduces the time required for assembly to improve work efficiency.

In order to solve the above-mentioned problem, the invention according to claim 1 of the present invention provides a reel support shaft at the center of a starter case attached to a housing on the engine side, and a rope reel provided rotatably around the reel support shaft. In the recoil starter that pulls out the recoil rope to rotate the rope reel and transmits this rotational force to the drive pulley coupled to the engine side to start the engine, the contact surface portion between the starter case and the housing (fan cover, etc.) A U-shaped guide groove that guides the withdrawal of the recoil rope to the outer peripheral edge of the starter case by forming a positioning portion by projections and depressions on the housing, and locking and fixing the starter case to the housing by a snap fit. Is formed with an opening .

According to the invention of claim 1, to form the positioning portion by the irregularities on the surface-contacting portion of the starter case and the housing, and engagement fixing by snap-fitting the starter case with respect to the housing, the outer peripheral edge of the starter case Since the U-shaped guide groove for guiding the withdrawal of the recoil rope is opened , the assembling work of the starter case is facilitated, and positioning and fixing can be realized with a simple structure.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. The recoil starter of the present invention includes a starter case 2 fixed to an engine-side housing 1 and provided with a reel support shaft 3 at the center, a spiral spring 4 disposed opposite to the bottom of the starter case 2, and a reel support shaft at the center. 3 is provided with a cylindrical shaft portion 6 that can be rotatably fitted and a rope reel 5 provided with a rope storage groove 8 of a recoil rope 7 on the outer peripheral side, and slides in the thrust direction outside the cylindrical shaft portion 6. A ratchet 10 that can be arranged, a ratchet guide 11 that is attached to the shaft end of the reel support shaft 3, and a return spring 12 that is provided between the ratchet guide 11 and the ratchet 10. Has been.

  The engine-side housing 1 is formed with a circular opening 14 for accommodating the drive pulley 13, and a hook-shaped locking portion 15 and a positioning recess 16 are formed at equal intervals on the periphery of the opening 14. .

  As shown in detail in FIG. 3, the starter case 2 is formed in a pan shape and is disposed at a position facing the drive pulley 13 coupled to the engine side. A cylindrical reel support shaft 3 is formed at the center of the circular bottom 17, and a ventilation hole 18 is formed at the peripheral edge of the bottom 17. In addition, positioning convex portions 20 and locking portions 21 are formed at equal intervals on the outermost peripheral edge of the starter case 2. Further, a U-shaped guide groove 19 (see FIG. 3) is formed in the outer peripheral edge portion 29 to guide the withdrawal of the recoil rope 7.

  The starter case 2 is positioned by engaging the positioning convex portion 20 with the positioning concave portion 16 of the housing 1 and snap-fitting the locking portion 21 of the starter case 2 to the vertical locking portion 15 of the housing 1. It is elastically locked to the housing 1.

  Note that the positioning concave portion 16 and the convex portion 20 are not limited to the illustrated form. A concave portion is formed in the housing 1 and a convex portion is formed in the starter case 2, and the housing 1 may not be made of metal but may be made of synthetic resin.

  As shown in FIG. 4, the rope reel 5 forms a spiral spring storage portion 22 on the outer peripheral side of one end of the central cylindrical shaft portion 6, and protrudes radially on the outer peripheral side of the spiral spring storage portion 22. A rope storage groove 8 is formed through a support piece 23, and a spiral spring 4 for rewinding and rotating the rope reel 5 is stored and disposed in the spiral spring storage portion 22, and one end thereof is attached to the starter case 2. The other end is fixed to the rope reel 5. The rope storage groove 8 has a U-shaped cross section and opens outward.

  A rope terminal storage portion 24 is formed between the support pieces 23 on the inner peripheral side of the rope storage groove 8. A notch 26 is formed in the groove wall 25 on the reel support shaft 3 side of the rope storage groove 8. The notch 26 is opened on the same side as the rope end storage portion 24, and the rope end storage portion 24 and the notch 26 of the groove wall 25 are formed to be continuous.

  On the opposite side of the spiral spring housing portion 22 of the rope reel 5, an annular wall 27 that is substantially parallel to the cylindrical shaft portion 6 is formed to project, and an engaging portion 28 is formed by cutting out a part of the annular wall 27. ing. The engaging portion 28 includes an inclined surface 28 a and a locking surface 28 b that follows the inclined surface 28 a, and the locking surface 28 b is formed in parallel with the axial direction of the cylindrical shaft portion 6.

  Next, as shown in FIG. 5, the ratchet 10 is formed by projecting ratchet arms 30 opposite to each other from an annular ratchet body 10a. Four engagement portions 31 are provided on the inner peripheral side of the ratchet body 10a. Projecting and a locking edge 32 is formed between the two engaging portions 31 facing each other.

  The ratchet 10 is formed so that the front and back are symmetrical. This is because it is not necessary to confirm the front and back when the ratchet 10 is assembled, and the assembling work is facilitated.

  Next, as shown in FIGS. 6A and 6B, the ratchet guide 11 guides the sliding of the ratchet 10 and prevents the ratchet 10 from coming off. A disk-shaped ratchet guide body 11a having a mating fitting hole 33 is formed with a spring receiving recess 34 on one surface, and a pair of locking pieces 35 projecting from the other surface. A locking jaw 36 is formed at the tip of the piece 35. The locking piece 35 has a narrow base and a wide tip. The tubular shaft portion 6 of the rope reel 5 is formed to fit between the two locking pieces 35.

  The ratchet guide 11 is rotatably disposed outside the cylindrical shaft portion 6, and is a saddle-shaped set spring that is latched and attached to an annular groove portion 37 (see FIG. 3) formed on the outer periphery of the shaft end of the reel support shaft 3. 38 (see FIG. 2). The set spring 38 is housed in the spring receiving recess 34 of the ratchet guide 11. For this reason, since the set spring 38 always rotates together with the ratchet guide 11, friction is applied to the ratchet guide 11, which becomes a sliding resistance when the ratchet guide 11 rotates.

  The ratchet 10 is slidably mounted along the locking piece 35 of the ratchet guide 11. That is, the locking jaw 36 at the tip of the locking piece 35 of the ratchet guide 11 is elastically locked to the locking edge 32 of the ratchet 10 by snap fitting, so that the locking piece 35 is engaged on both sides of the locking edge 32. It is sandwiched between the joint portions 31. For this reason, the ratchet 10 rotates with the ratchet guide 11, is guided by the locking piece 35, and slides along the axial direction of the reel support shaft 3.

  The return spring 12 is a coil spring and is disposed between the ratchet guide main body 11 a and the ratchet 10. For this reason, the ratchet 10 is always urged so as to be in a position on the base side of the cylindrical shaft portion 6.

  Next, as shown in FIG. 7, the drive pulley 13 is fixed to the crankshaft 41 of the engine, and an annular wall 40 is formed so as to surround the crankshaft 41, and the end of the annular wall 40 is inclined. An engaging portion 42 is formed which includes a surface 42a and a locking surface 42b following the surface 42a. The locking surface 42 b is formed in parallel with the axial direction of the crankshaft 41. The inclined surface 42a is opposite to the inclined surface 28a of the rope reel 5 when viewed from the radial direction.

  The annular wall 40 of the drive pulley 13 is configured to be located inside the outer peripheral edge portion 29 of the rope reel 5.

  As shown in FIG. 1, a part of the crankshaft 41 (or a part of the nut on the crankshaft) is inserted and arranged in the internal space of the reel support shaft 3 of the starter case 2. Thus, the reel support shaft 3 is supported by the starter case 2 being fixed by the positioning irregularities 16 and 20 and the locking portions 15 and 21 on the outer peripheral edge thereof, and also by the crankshaft 41 of the engine. It is supported.

  By the way, when assembling a recoil starter with the above-described components, first, several parts are sub-assembled as shown in FIGS.

  That is, the recoil rope 7 is wound around the rope reel 5, the spiral spring 4 is accommodated in the spiral spring accommodating portion 22, and one end thereof is locked to the rope reel 5. In this way, the reel subassembly A is completed. When the terminal of the recoil rope 7 is stored in the terminal storage part 24, the knot 7a is made in advance as described above and pushed into the notch 26 and the terminal storage part 24 as shown in FIG. Since the operation of passing is unnecessary, the storing operation can be performed easily and quickly.

  Similarly, the return spring 12 is mounted on the outer side of the locking piece 35 of the ratchet guide 11, the ratchet 10 is further fitted, the return spring 12 is bent, and the locking jaw 36 at the tip of the locking piece 35 is attached to the ratchet 10. The locking edge 32 is locked by snap fitting. In this way, the ratchet subassembly B is completed.

  When assembling the above subassemblies A and B to the starter case 2, first, the cylindrical shaft portion 6 of the reel subassembly A is fitted and mounted on the reel support shaft 3 of the starter case 2. Next, the ratchet subassembly B is fitted and attached to the outside of the cylindrical shaft portion 6. Then, a set spring 38 is locked and attached to the shaft end of the reel support shaft 3. With this process, the main body of the recoil starter is completed on the engine. The recoil rope 7 may be pulled out from the guide groove 19 (see FIG. 3) of the starter case 2.

  Next, when the recoil starter is assembled to the housing 1 of the engine, as shown in FIG. 1, the positioning recess 16 on the outer peripheral edge of the starter case 2 is fitted into the protrusion 20 of the housing 1, and the starter case 2 What is necessary is just to latch the latching | locking part 21 to the latching | locking part 15 of the housing 1 by a snap fit. Thereby, the starter case 2 is fixed in a positioned state.

  As described above, the recoil starter is completed by assembling several parts in advance to prepare the subassemblies A and B, and assembling these subassemblies A and B to the starter case 2 sequentially. Moreover, since no screws are used, the work efficiency is good and the assembly can be easily and quickly in a short time.

  In addition, since the starter case 2 having the reel support shaft 3 is mounted by snap fitting, the assembly work is facilitated, and a part of the engine crankshaft 41 (or a part of the nut on the crankshaft) is reeled. Since it is inserted and arranged in the inner space of the support shaft 3, when the recoil rope 7 is pulled out strongly and the rope reel 5 is rotated, the starter case 2 is deformed by receiving a strong force on the pull-out side, but the reel support shaft 3 is a crankshaft. Since it is supported by 41, deformation is suppressed. Therefore, the rope reel 5 can be smoothly rotated and the engine can be started stably.

  In particular, in the ratchet subassembly B, the ratchet 10 and the return spring 12 may be disposed outside the locking piece 35 of the ratchet guide 11 and the tip of the locking piece 35 may be locked to the ratchet 10 by snap fitting. Therefore, it can be assembled integrally in advance. When assembling to the starter case 2, the above-described sub-assembly is simply fitted to the cylindrical shaft portion 6 of the rope reel 5, so that the number of assembling steps can be reduced.

  Further, since the ratchet guide 11 can be prevented from coming off and friction can be applied to its rotation only by locking and mounting the set spring 38 in the annular groove 37 at the shaft end of the reel support shaft 3, work such as screwing can be performed. Compared to the above, it is much easier, and it is not necessary to provide a separate friction applying means, and the number of assembling steps can be reduced.

  Furthermore, since the positioning portion by the concavo-convex portions 16 and 20 is formed on the contact surface portion between the starter case 2 and the housing 1 and the starter case 2 is locked and fixed to the housing 1 by a snap fit, the starter case 2 is assembled. Work becomes easy and positioning and fixing can be realized by a simple structure.

  Next, the usage mode of the above-described recoil starter will be described. When the recoil rope 7 is pulled out strongly and the rope reel 5 is rotated, the inclined surface of the annular wall 27 engages with the ratchet arm 30 of the ratchet 10. Since the ratchet guide 11 cannot be rotated by the frictional force of the set spring 38, the ratchet 10 in the standby position moves in the axial direction as shown by the dotted line in FIG. 1 against the return spring 12 along the inclined surface 28a. Then, it is locked to the locking surface 28b. Since the locking surface 42b of the annular wall 27 of the drive pulley 13 is located on the shaft end side, the ratchet arm 30 contacts the locking surface 42b. Since the ratchet 10 rotates together with the rope reel 5 when it hits the locking surface 42b, the rotation of the rope reel 5 is transmitted to the drive pulley 13 via the ratchet 10, the drive pulley 13 rotates, and the engine starts. When the engine is started, the rotation of the drive pulley 13 is faster than the rotation of the rope reel 5, so that the inclined surface 42a of the drive pulley 13 is engaged with the ratchet arm 30, and the ratchet arm 30 is in the standby position along the inclined surface 42a. Extruded to the side. Further, the ratchet 10 returns to the standby position by the spring force of the return spring 12. When the pulling force of the recoil rope 7 is released, the rope reel 5 rotates reversely by the rewinding force of the spiral spring 4, so that the recoil rope 7 is rewound onto the rope reel 5 and the engine starting operation is completed.

It is a vertical side view of the recoil starter of the embodiment of the present invention. Rear view of the recoil starter Perspective view of starter case Rope reel perspective view Ratchet perspective view (A) (b) is a perspective view of a ratchet guide Perspective view of drive pulley (A) (b) is explanatory drawing of the assembly method of a recoil starter

2 Starter case 3 Reel spindle 5 Rope reel 7 Recoil rope

Claims (1)

A reel support shaft is provided at the center of the starter case attached to the housing on the engine side, the recoil rope is pulled out from the rope reel provided rotatably around the reel support shaft, and the rope reel is rotated. In a recoil starter that is transmitted to a drive pulley coupled to the engine and starts the engine,
While forming a positioning portion by unevenness on the contact surface portion between the starter case and the housing (fan cover, etc.), the starter case is locked and fixed to the housing by a snap fit ,
A recoil starter characterized in that a U-shaped guide groove is formed in the outer peripheral edge of the starter case to guide the withdrawal of the recoil rope .

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