JP2006291722A - Engine start device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an engine start device reducing the number of components and provided with a start mode change over means, which can be easily installed. <P>SOLUTION: This device is provided with a rotary drive part D, a buffer/accumulation means 130, 131 buffering drive of the drive part while accumulating power, and a rotary driven part M starting an engine by release of accumulated power of the buffer/accumulation means 130, 131. When power accumulated by the buffer/accumulation means 130, 131 becomes accumulation power necessary for engine start, the accumulated power is released and transmitted to the rotary driven part M to start engine via the rotary driven part M. A first engagement and disengagement member 141 which consists of an elastic member engaging and disengaging with the buffer/accumulation means 130, 131 and preventing/permitting reverse rotation of the buffer/accumulation means at a time of start, is included. The first engagement and disengagement member 141 can dispence with a conventional torsion spring which consists of rigid material for urging the first engagement and disengagement member. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a starter for an internal combustion engine, and preferably a buffer / accumulation means is interposed between a rotation drive unit and a rotation follower, and the power of the rotation drive unit is transmitted via the buffer / accumulation unit. The first start mode that is directly transmitted to the rotation follower and the power stored in the buffer / power storage means when desired, by storing the power of the rotation drive unit exclusively in the buffer / power storage means The present invention relates to an engine starter having mode switching means for switching to a mode with a second start mode in which the rotation follower is rotated.

  A manual starter for an internal combustion engine usually rotates a recoil reel by pulling a recoil rope, and transmits the rotation of the recoil reel to the crankshaft of the engine to start the engine. The engine starter of the present invention not only needs to increase the pulling speed of the recoil rope to some extent, but also has a long pulling length. For this reason, an internal combustion engine cannot be easily started for an elderly person or a person with weak power. Therefore, an engine starting device that can easily start an internal combustion engine even by a person having a small recoil rope pulling force is disclosed in, for example, Japanese Utility Model Laid-Open No. 1-91075 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2001-132591 (Patent Document). Document 2), Japanese Patent Application Laid-Open No. 2002-327666 (Patent Document 3), Japanese Patent Application Laid-Open No. 2003-269300 (Patent Document 4), Japanese Patent Application Laid-Open No. 2001-65435 (Patent Document 4), etc. .

  Of these, in order to start the engine with the engine starting device of Patent Document 1, the stopper member is previously engaged with the ratchet on the driven side, the recoil rope is pulled an appropriate number of times, and the recoil drum is rotated to be sufficient for the energy storage spring. If the spring force is accumulated and the stopper member and the ratchet are disengaged at the time of starting the engine, the crankshaft is rotated by the spring force of the power storage spring to start the engine. When accumulating the spring force in the energy storage spring, an extra load from the engine is not applied, so a force sufficient to wind up the recoil spring and the energy storage spring is sufficient. As a result, the pulling force of the recoil rope can be small, and even a person with weak power can easily perform the pulling operation of the recoil rope and can start the engine reliably when necessary.

  On the other hand, the engine starting devices disclosed in Patent Documents 2 to 4 exclude the stopper member from the engine starting device disclosed in Patent Document 1, and the spring force accumulated in the accumulator mainspring exceeds the maximum load in the compression stroke of the engine. Until the spring force of the spring is not released until the spring force of the spring exceeds the maximum load in the compression stroke of the engine, the spring force is released and the crank is rotated to automatically start the engine. Let

  Here, Patent Documents 2 and 3 are substantially provided with the above-mentioned functions, although a part of the mechanism is different. The difference in the mechanism is that Patent Document 2 supports the mainspring storage box, which is a part of the buffering / accumulating means, on the support shaft via the one-way clutch, whereas Patent Document 3 discloses the mainspring storage box. One-way rotating means is provided which is rotatably supported by the support shaft and which allows only rotation in the engine rotation direction on the outer peripheral portion of the mainspring storage box. As described above, providing the one-way rotating means on the outer peripheral portion of the mainspring storage box is more advantageous in terms of design and processing than providing the same-direction rotating means on the rotating shaft portion. In any case, the engine starting devices of these documents 2 and 3 are configured so that the mainspring storage box can be rotated only in one direction by the pulling operation of the recoil rope, and the spring force stored in the mainspring is maintained.

  On the other hand, in the above-mentioned Patent Document 4, a mainspring storage box integrated with a recoil reel around which a recoil rope is wound is rotatably supported on a support shaft without interposing a one-way clutch or the like, and accumulates power in a mainspring spring. If the recoil rope pulling operation is stopped in the middle of the operation, the mainspring storage box is reversed together with the coil reel in the direction opposite to the driving direction of the engine to release the spring force of the mainspring.

  Further, the engine starting device of Patent Document 5 includes a mainspring accumulating mechanism, a manual recoil reel that causes the mainspring accumulating mechanism to accumulate rotational force, and rotation on the output side of the mainspring accumulating mechanism to prevent accumulation. A reset lever having a stopper that holds the applied rotational force up to a predetermined torque, and a transmission mechanism that transmits the accumulated rotational force to the crankshaft of the internal combustion engine when the stopper is released. The reset lever can be manually switched from the stop position to the free position, and the engine can be automatically started by the same operation as in Patent Document 2. That is, according to this engine starting device, unless the reset lever is operated and the stopper is set to the free position in a normal state, the stopper is at the stop position and prevents the output side of the mainspring energy storage mechanism from rotating. In this state, pulling the recoil rope several times to cause the mainspring energy storage mechanism to store sufficient energy to start the engine, and at the same time, the reset lever automatically moves to the free position to start the engine. Therefore, even a weak person can easily operate the engine.

  By the way, according to the engine starting device of Patent Document 1, even if the recoil rope is pulled when the stopper member is not engaged with the second ratchet, the second ratchet causes the outer end portions of the recoil drum and the second spring to be pulled. Since it rotates together with the case to be fixed, no spring force is accumulated in the second spring, and the engine cannot be started. Therefore, in order to start the engine with this engine starting device, it is necessary to engage the stopper member with the second ratchet in advance. In addition, according to this starting device, the required spring force is not accumulated unless the recoil rope pulling operation is performed a plurality of times. Therefore, for an operator having a normal force, it is troublesome to start and it is difficult to get used to it.

  On the other hand, in the engine starting devices of Patent Documents 2 to 4, since the engine can be automatically started simply by pulling the recoil rope, the working efficiency is improved if the working space is wide and stable. However, even if you try to prun trees using a chainsaw equipped with this engine starter, for example, it is an unstable work site that is inevitably high and has poor footing, and there are other branches and leaves in the vicinity. Due to the overhang, it is often impossible to increase the pulling operation of the recoil rope.

  Further, the engine starting devices disclosed in Patent Documents 2 to 4 are also mounted on a shoulder-type, for example, a brush cutter, which performs work with the engine on the back. This backpack-type mower has an engine and a long operation pipe connected by a flexible pipe, and a flexible shaft is inserted through the flexible pipe and the transmission inserted through the operation pipe. The rotating blade attached to the tip of the operation tube is rotated by the rotation of the transmission shaft coupled with the shaft. In addition to the flexible pipe, a plurality of wires and lead wires are interposed between the engine and the connecting end of the operation tube. In order to start the engine of such a backpack type mower, for example, a long operation tube is gripped with the left hand and the recoil rope is pulled with the right hand.

  Since the pulling operation at this time carries the engine on the back, the operation handle of the recoil rope is pulled forward from the front. This operation is not only very difficult to operate, but also requires a very large pulling force as compared with the case where the recoil rope is pulled forward. During this engine starting operation, the rotating blade at the tip must be held in the air while paying attention to the surrounding area while holding the front end of the long operation tube with the left hand. .

  In particular, in the engine starting devices disclosed in Patent Documents 2 and 3, even if the pulling operation of the recoil rope is stopped halfway and the rope is automatically returned to the original state wound around the recoil reel, the spring Since the reversal of the storage box is sealed by the one-way rotating means, the stored power stored in the mainspring is maintained as it is. It is easy for the engine to start unexpectedly due to the release of the accumulated power. In that regard, even if the engine starting device of Patent Document 4 stops the pulling operation of the recoil rope halfway and releases the recoil rope, the spring storage box and the recoil reel are brought together by the reaction force of the stored spring force. Since the recoil rope is automatically rewound and the spring is automatically released from the stored power, the engine is not inadvertently started.

  On the other hand, the engine starting device disclosed in Patent Document 5 is reset when a sufficient amount of stored force is stored to start the engine in the buffer / power storage means by pulling the recoil rope when the stopper is applied. The lever automatically moves and the stopper comes off, and the engine starts automatically. Therefore, even in this device, it is impossible to arbitrarily select the engine start time. Also, in order to start the engine by moving the reset lever to the free position, the recoil rope must be pulled large and quickly as in the conventional case. Therefore, at the work site where the operation space around the high place and the surroundings is narrow as described above and the pulling operation of the recoil rope is difficult, the recoil rope is pulled several times at that site and the engine is started. If this pulling operation is also impossible, it is a manual operation, which is extremely inefficient.

  By the way, in the engine device disclosed in the above-mentioned Patent Document 1, it is not possible to examine at a glance how many times the recoil rope pulling operation is performed, the spring can store a sufficient accumulated force to start the engine. Therefore, the recoil rope pulling operation is often performed an extra number of times. Or, when the number of operations for pulling the recoil rope is small, the engine is not started even if the stopper is removed, and the stored power of the folding angle stored in the mainspring is released. In addition, the above Patent Documents 2 to 4 cannot predict the time when the spring stores enough power to start the engine. For this reason, the spring force of the mainspring fluctuates during long use, and the engine start time is likely to be shifted, which cannot be predicted.

  On the other hand, in the engine starting device of Patent Document 5 described above, when the stored power sufficient to start the engine is accumulated in the mainspring during the recoil rope pulling operation, the engine is automatically and reliably started. Insufficient pulling operation is eliminated. However, as in Patent Documents 2 to 4, it is difficult to predict the start timing. In addition, the recoil rope pulling operation is performed in advance, and the engine cannot be started with a simple operation at an arbitrary place at an arbitrary time.

  In order to solve the various problems of the conventional manual engine starter at the same time, the present applicant previously proposed an invention according to Japanese Patent Application No. 2004-173578 (Patent Document 6). The basic configuration includes a rotation driving unit that rotates by a pulling operation of the recoil rope, and a rotation driven unit that transmits the rotation of the rotation driving unit, and a buffer and a rotation between the rotation driving unit and the rotation driven unit. An accumulating means is interposed, and the buffer / accumulating means accumulates power while buffering by driving the rotary drive unit in the process of driving the rotary drive unit, and the rotational follower unit is driven by the accumulated force. In the starting device of the engine to be driven, the buffer / accumulation means starts from a first start mode in which the rotation of the rotation drive unit is directly transmitted to the rotation follower via the buffer / accumulation means. , The rotation of the rotation drive unit is stored exclusively in the buffer / power storage means, and the mode is changed to the second start mode in which the stored power stored in the buffer / power storage means is released and the rotation follower is rotated when desired. Mode switching means for switching; The first and second engagement / disengagement members that engage / disengage the buffer / accumulation means and the rotation follower to prevent / allow reversal of the buffer / accumulation means and the rotation follower, respectively. And a single operating means for linking and disengaging the first and second engaging / disengaging members.

With this configuration, the engine is started by pulling the recoil rope at a stroke in the state of the first start mode in a normal wide work site, but the first start mode is set to the second in a place where the recoil rope pulling operation is difficult. After switching to the start mode and pulling the recoil rope in a place where it is easy to perform the pulling operation in advance and storing the necessary energy in the buffering / accumulating means, switching the mode switching operation means, for example, one-push switching By switching from the second start mode to the first start mode using a switch or the like, the engine can be started instantly. The switching mode after the engine is started is always the first start mode, that is, the first and second engaging / disengaging means are disengaged from the buffering / accumulating means and the driven portion. In this first start mode, for example, as in the engine starter disclosed in Patent Document 4 described above, after stopping the recoil rope pulling operation, the spring force stored in the buffering / accumulating means is reduced. It comes to have the same function as the model released naturally. Therefore, in the first start mode, even if the recoil rope pulling operation is stopped and left before the engine starts, the stored power is spontaneously released from the buffer / power storage means and disappears. The engine can be prevented from starting.
Japanese Utility Model Publication No. 1-91075 JP 2001-132591 A JP 2002-327666 A JP 2003-269300 A JP 2001-65435 A Japanese Patent Application No. 2004-173578

After making the proposal by the above-mentioned patent document 6, as a result of further examination, it was found that the following problems existed.
According to the embodiment shown in FIG. 2 of Patent Document 6, each of the first and second engaging / disengaging members has a square shape, and its bent portion is close to the upper wall surface of the bottom portion of the cover case body. It is pivotally mounted alongside. The first engagement / disengagement member includes an engagement / disengagement claw portion that engages / disengages with the outer peripheral ratchet formed in the buffer / accumulation means, and an operation portion that rotates the engagement / disengagement claw portion around a bent portion, The engaging / disengaging claw portion is biased by a torsion spring in a direction to engage with the outer peripheral ratchet teeth of the buffering / accumulating means. One second engagement / disengagement member includes an engagement / disengagement claw portion that engages / disengages with the ratchet of the rotation follower portion and an operation portion that rotates the engagement / disengagement claw portion around a bent portion, It is urged in one direction by a torsion spring in the direction of engagement with the ratchet.

  Further, a slide switch is attached to the upper end portion of the cover case body so as to be slidable in the front-rear direction. The slide switch has a structure in which the upper part is bent upward and the bulging upper surface has a large number of uneven surfaces, and the slit is formed in the cover case body so as to protrude downward from the lower surface. And a slide piece. This slide piece and the tip of the operation part of the second engaging / disengaging member are connected by a link piece. One end of the link piece is attached to the distal end of the operation portion of the second engaging / disengaging member so as to be relatively rotatable, and the other end of the link piece is slidably attached to a slit formed in the slide piece.

  In the state where the second engagement / disengagement member is detached from the ratchet via the link piece, the distal end portion of the operation portion of the second engagement / disengagement member is the first engagement / disengagement member. The distal end portion of the operating portion of the detaching member is pushed down from above, and the engaging / disengaging claw portion of the first engaging / disengaging member is disposed so as to be disengaged from the outer peripheral ratchet teeth of the buffering / accumulating means. On the other hand, by sliding the slide switch in the opposite direction, the first and second engaging / disengaging members are mutually restrained from linking with the link piece, and are buffered by the elasticity of each torsion spring. The outer peripheral ratchet teeth of the force storage means and the ratchet of the rotation follower are rotated in the direction in which they are engaged with each other.

As described above, the switching means between the first start mode and the outer two start mode disclosed in Patent Document 6 includes the first and second engagement / disengagement members, the two torsion springs, the slide switch, and the second engagement. It consists of as many as six link pieces that connect the removal member and the slide switch, and its assembly is extremely complicated.
SUMMARY OF THE INVENTION An object of the present invention is to provide an engine starter having start mode switching means that reduces the number of parts and can be easily assembled.

  An object of the present invention is to provide a rotational drive unit, which is a basic configuration of the present invention, a buffer / power storage unit that stores power while buffering power by rotating the rotary unit by driving the drive unit, and the buffer / power storage unit. A rotation follower that starts the engine by releasing the stored power of the engine, and when the stored power stored in the buffer / power storage means is the stored power necessary for starting the engine, the stored power is released and the An engine starter that is transmitted to a rotational follower and starts the engine via the rotational follower, and engages / disengages the buffer / accumulation means to prevent / allow reversal of the buffer / accumulation means. It has a first engagement / disengagement member and switching operation means for engaging / disengaging the first with the buffer / accumulation means, and the first engagement / disengagement member is made of an elastic member. This is effectively achieved by the engine starting device.

  According to a preferred aspect, the first engagement / disengagement member is provided at one end thereof with a pivot portion pivotally attached to the case body of the engine starter, and an engagement / disengagement extending from the pivot attachment portion. A leaf spring portion is extended on the opposite side of the pivot attachment portion, and a pin parallel to the axis of the pivot attachment portion projects from the tip of the leaf spring portion. According to a further preferred aspect, the second engaging / disengaging member has a character-like second engaging / disengaging member that is connected to the engaging / disengaging operation of the first engaging / disengaging member. The central part has a pivot part pivotally attached to the cover of the engine starter, and has an engagement / disengagement claw part on one end side, and a long hole is formed on the other end part. An engagement / disengagement claw portion is biased in a direction to engage with the rotation follower portion, the pin of the first engagement / disengagement member is inserted into a long hole of the second engagement / disengagement member, and the pin is a leaf spring portion It is urged | biased by the direction which engages with the said buffer storage means by the spring force of.

  More preferably, the switching operation means rotates the second engagement / disengagement member against the bias to release the engagement with the rotation follower and rotates the second engagement / disengagement member. In response to the movement, the pin of the first engagement / disengagement member is slid in the elongated hole of the second engagement / disengagement member, and the first engagement / disengagement member is rotated against the spring force of the leaf spring portion, An operation member for releasing the engagement between the engagement / disengagement claw portion of the first engagement / disengagement member and the buffer / accumulation means is provided.

  Further, it is preferable that the operation member is pivotally attached to a case body of the engine starting device, and a cam surface is formed on a surface facing the second engagement / disengagement member. The buffer / accumulation part preferably has a mainspring barrel that engages with and disengages from the first engagement / disengagement member, and an accumulation spring that has one end supported by the incense box and the other end supported by the rotation follower, The rotary follower has a ratchet wheel that engages and disengages with the second engaging / disengaging member. Furthermore, it is preferable to have a torque limit mechanism that operates when the accumulated force by the buffering / accumulating means exceeds a load necessary for starting the engine.

Effect

  In the above basic configuration of the present invention, the operational effects of the switching means for the first and second start modes are described in detail in the above-mentioned Patent Document 6, and the details thereof are referred to the same Document 6, and here The effect regarding the said 1st engagement / disengagement member which is the main structures of this invention is demonstrated.

  The operation member according to the present invention includes a first and second engagement / disengagement member, and a switch for connecting and disengaging the first and second engagement / disengagement members to and from the buffer / accumulation means and the rotation follower. Since it is composed of four parts, that is, an operation member and one torsion spring that always urges the second engaging / disengaging member in a direction in which the second engaging / disengaging member is engaged with the rotation follower, the number of parts is larger than the conventional one. Not only will it be reduced, but its assembly is extremely simple. This is because the first engagement / disengagement member is composed of an elastic member, so that a torsion spring is not required for the first engagement / disengagement member, and the elastic shape of the first engagement / disengagement member is appropriately designed, It is possible to change the connecting operation of the first and second engaging / disengaging members. Specifically, for example, the operation of disengaging the first engagement / disengagement member from the buffering / accumulating means is slightly delayed from the operation of disengaging the rotation engagement portion of the second engagement / disengagement member. As a result, after sufficiently transmitting the accumulated force enough to start the engine to the rotary follower, the engagement between the first engagement / disengagement member and the buffer / accumulation means is released, and the remaining accumulated force is released, and the accumulated energy is released. Do not leave extra energy in the mainspring.

  In addition, even in the present invention, using the spring barrel and the spring for power storage that have been conventionally used for the buffering and power storage means, and using the ratchet wheel that is also widely used for the rotation follower, There is no need to procure special parts for the present invention.

  Further, if a torque limit mechanism is further provided in the rotating part of the engine starting device, it is detected that the accumulated force by the buffer / accumulating means exceeds the load necessary for starting the engine, so that no further accumulation is performed. Makes it possible to As a result, when this torque limit mechanism is activated, it is not necessary to store energy in the buffer / accumulation means any more, and the recoil rope can be pulled without excess or deficiency, and unnecessary pulling operation is unnecessary. When the necessary storage force is stored in the buffering / accumulating means, the signal generating means is activated together with the operation of the torque limit mechanism, for example, to generate a sound or light notification signal. You can easily know that it was activated.

Hereinafter, a preferred embodiment of an engine starter according to the present invention will be specifically described with reference to the drawings. In the present embodiment, a power transmission mechanism between a starter of a small air-cooled internal combustion engine applied to the chainsaw and the engine is exemplified. However, the same type of engine starter and a brush cutter equipped with the engine, Of course, the present invention is applied to various portable work machines such as a rotary saw.
FIG. 1 is an exploded perspective view showing an arrangement relationship of constituent members when the engine starter according to the present embodiment is assembled. FIG. 2 shows an assembly structure of the engine starter and the crankshaft of the engine according to the present embodiment. FIG.
As indicated by phantom lines in FIG. 2, a fan 106 is fixed to the crankshaft 105 of the engine, and a rear surface of the fan 106 on the engine starter side is a component member of a centrifugal clutch mechanism described later. A pivotal support portion 106 a that pivotally supports the shape engaging / disengaging member 107 is integrally formed with the crankshaft 105 interposed therebetween. A pair of the pivot portions 106a are arranged with a phase difference of 180 ° across the crankshaft 105, and the shape thereof is a fan shape when viewed from the engine starter side. The hook-like engagement / disengagement member 107 is pivotally attached to these pivotal support portions 106a. As shown in FIG. 2, the hook-like engagement / disengagement member 107 has a shape in which a claw portion 107b that is bent at a right angle to one end of the hook-like engagement / disengagement portion main body 107a rises when viewed from the side. A screw insertion hole is formed through which a set screw 106b to be screwed into the pivotal support portion 106a is inserted. A torsion spring (not shown) is interposed between the hook-shaped engagement / disengagement member 107 and the fan 106, and the claw portion 107b is always pressed against the crankshaft side by the elasticity of the torsion spring. Yes.

  In the engine starter 100 according to the present embodiment, the rotational center of the rotational follower M that is rotatably attached to the cylindrical boss 101a of the half case body 101 and the axial center of the crankshaft 11 on the engine side face each other. It is assembled in this way. As shown in FIG. 2, all the constituent members of the engine starter 100 are accommodated in the half case body 101 on the side opposite to the engine. As shown in the figure, a cylindrical boss portion 101a projects from the half case body 101 toward the crankshaft side. An inner thread is cut on the inner surface of the cylindrical boss portion 101a, and constituent members of each engine starting device 100 described below are sequentially assembled to the cylindrical boss portion 101a and fixed by a set screw 102.

  As shown in FIG. 1, the engine starter 100 includes a rotation driving unit D and a rotation driven unit M. The rotational drive part D is formed with a recoil spring 110 that abuts and fixes the outer hook end 110a to the inner surface of the half case body 101, and a circular hole 112 that is fitted around the cylindrical boss part 101a at the center. A mainspring case 113 that houses the same recoil spring 110, contacts the inner surface of the half case body 101 together with the outer hook end 110a of the mainspring 110, and a recoil rope 115 having a grip 114 at one end. And a recoil reel 116 around which the recoil rope 115 is wound with the other end of the recoil rope 115 wound around and fixed to a part of the circumferential surface.

  As shown in FIGS. 1 and 3, one rotational follower M includes a ratchet wheel 120 in which first and second ratchet portions 121 and 122 having different diameters are integrally arranged on a coaxial line. As shown in FIGS. 4 and 5, a circular protrusion 123 having a center O ′ at a position deviated from the rotation center O of the ratchet wheel 120 protrudes from the central portion of the back surface of the ratchet wheel 120 on the rotation drive part D side. A U-shaped notch groove 123a toward the center O ′ is formed in a part of the peripheral edge of the circular protrusion 123. A second engagement / disengagement member 142 described later engages / disengages with the ratchet teeth 121a of the large-diameter first ratchet portion 121, and the ratchet teeth 122a of the small-diameter second ratchet portion 122 include the crank as shown in FIG. The said claw part 107b which is a structural member of the centrifugal clutch mechanism attached to the axis | shaft 105 engages / disengages. According to the illustrated example, the first ratchet portion 121 and the second ratchet portion 122 have four ratchet teeth 121a and 122a, and both the ratchet portions 121 and 122 allow only rotation in the same direction. The engaging surface is provided on the side opposite to the direction in which rotation is allowed. Since the small-diameter second ratchet portion 122 is engaged with the claw portion 107b, the mainspring barrel 130, which is a part of the buffering / accumulating means in the present invention, rotates in the accumulating direction until the engine is started. It is put in the state stopped without following.

  As shown in FIGS. 1 and 2, between the rotation driving unit D and the rotation driven unit M, the mainspring barrel 130 which is a buffer / accumulation unit of the present invention and the accumulator stored in the mainspring barrel 130. A mainspring 131 is interposed. According to the present embodiment, as shown in FIG. 6 with a part broken away, the outer hook portion 131a of the energy storage spring 131 is formed on the inner peripheral surface of the mainspring housing portion 130a of the mainspring barrel 130. A plurality of protrusions 130b for engaging the power storage spring 131 in the power storage direction protrude at equal intervals. The shape of the protrusion 130b is an engagement surface 130b-1 for engaging the outer hook 131a of the energy storing spring 131 when rotating in the energy storing direction of the recoil reel 116. An inclined surface 130b-3 that is gently inclined downward toward the inner peripheral surface of the accommodating portion 130a from the apex portion 130b-2 toward the counter-accumulation direction is formed. On the other hand, the inner hook portion 131b of the power storage spring 131 is fitted and fixed to the U-shaped notch groove 123a formed in the circular protrusion 123 of the ratchet wheel 120 of the rotation driven portion M. The open surface on the driven portion side of the mainspring barrel 130 is closed by an annular cover 133 to restrict the axial movement of the power storage spring 131 housed inside.

  The protrusion 130b constitutes a part of the torque limit mechanism. When the accumulated force of the energy storing spring 131 reaches a sufficient amount to start the engine, the protrusion 130b is engaged with the outer hook portion 131a. Cannot be maintained, the engagement with the outer hook portion 131a is disengaged, and the outer hook portion 131a passes over the protrusion 130b one after another, so that no further power can be stored in the power storage spring 131. The sound generated when the outer hook 131a exceeds the protrusion 130b informs the outside that the accumulated force of the energy storing spring 131 has reached its limit. In the present embodiment, the torque limit mechanism is configured between the mainspring barrel 130 and the accumulator mainspring 131. However, for example, the rotation follower M may be provided with a torque limit mechanism.

  As shown in FIGS. 6 and 7, the outer circumferential surface of the mainspring barrel 130 is allowed to rotate in the power accumulation direction (clockwise in FIG. 6) of the power accumulation spring 131 housed therein. A plurality of outer peripheral ratchet teeth 130c as a one-way rotation mechanism for preventing rotation are integrally formed with a pitch difference alternately. A ratchet mechanism is generally used as the one-way rotating mechanism, but various other types of one-way rotating mechanisms can be adopted, and the installation site is not necessarily limited to the outer peripheral surface of the mainspring barrel 130. The first engagement / disengagement member 141 is engaged / disengaged with the outer peripheral ratchet teeth 130c. On the other hand, a small ratchet portion 132 is formed at the center of the back surface of the mainspring barrel 130 facing the recoil reel 116 as shown in FIG. 7, and the portion of the recoil reel 116 facing the small ratchet portion 132 is formed. As shown in FIG. 1, an engagement / disengagement claw bar 116a that elastically engages / disengages with the ratchet teeth 132a of the small ratchet portion 132 is provided to rotate the mainspring barrel 130 only in the direction of power accumulation. . The engagement surface of the outer peripheral ratchet teeth 131c with the second engagement / disengagement member 142 is directed in the direction of accumulation of the energy storing spring 131, and the small ratchet portion 132 provided on the back side of the spring barrel 130. The engagement surface of the ratchet tooth 132a with the engagement / disengagement claw bar 116a is directed in a direction opposite to the engagement surface of the ratchet tooth 121a of the first ratchet portion 121 of the ratchet wheel 120 of the rotation follower M. .

  According to the illustrated example, the ratchet teeth 132a of the small ratchet portion 132 are formed integrally with the mainspring barrel 130 with a phase difference of 90 °, and the engagement / disengagement claw bar 116a is opposed to the mainspring barrel side of the recoil reel 116. Two of them are arranged point-symmetrically with respect to the rotation center of the recoil reel 116 with a phase difference of 180 ° at the peripheral edge thereof, and one end thereof is pivotally attached to the peripheral edge of the recoil reel 116. The engaging / disengaging claw bar 116a is always urged in a direction to engage with the ratchet teeth 132a by a torsion spring 116b (not shown). The pair of engaging and disengaging claw hooks 116a are engaged simultaneously with two ratchet teeth 132a of the four ratchet teeth 132a arranged with a phase difference of 180 °, so that the recoil reel 116 and the spring barrel 130 are engaged with each other. Only the recoil reel 116 can rotate in the direction of energy accumulation and in the direction of anti-energy accumulation.

  Here, in this embodiment, the two engaging / disengaging claw rods 116 a of the recoil reel 116 engage with the two ratchet teeth 132 a of the small ratchet portion 132 formed on the back side of the mainspring barrel 130. In this state, by pulling the recoil rope 115 and rotating the recoil reel 116 in the accumulating direction, and rotating the mainspring barrel 130 in the same accumulating direction (clockwise in FIG. 6), the second engagement / disengagement is performed. A sufficient accumulating force is applied to the accumulator mainspring 131 with the ratchet wheel 120 in a stopped state with the member 142 engaged. When sufficient energy is stored in the energy storage spring 131, the engagement of the second engagement / disengagement member 142 and the ratchet wheel 120 is disengaged, and the engine (not shown) is instantly started.

  FIG. 8 is an enlarged view of the first engagement / disengagement member 141 that engages / disengages with the outer peripheral ratchet teeth 130 c of the mainspring barrel 130. FIG. 9 shows the second engagement / disengagement member 142 that engages / disengages with the large-diameter first ratchet portion 121 of the ratchet wheel 120. Here, since the main spring barrel 130 is made of plastic, the first engaging / disengaging member 141 is also made of plastic, and the second engaging / disengaging member 142 is made of a sheet metal material.

  As shown in FIG. 8, the first engaging / disengaging member 141 has a disk-like pivoting portion 141a and a triangular plate-like engaging / disengaging claw portion 141b extending from the pivoting portion 141a. The other half is the same as the pivoting portion 141a that extends in the reverse direction from the pivoting portion 141a substantially perpendicular to the straight line connecting the center of the pivoting portion 141a and the tip of the engaging / disengaging claw portion 141b. A thick plate spring portion 141c and a pin 141d projecting in parallel with the axis of the pivot portion 141a from one side surface of the free end of the plate spring portion 141c are provided. The leaf spring portion 141c has a base portion 141c-1 slightly protruding in the radial direction of the pivot attachment portion 141a, and a circular direction in a direction opposite to the extending direction of the engagement / disengagement claw portion 141b following the base portion 141c-1. It comprises a curved portion 141c-2 that curves and projects in an arc. In addition, a loose insertion hole 141 a-1 for loosely inserting a shaft portion protruding from the inner surface of the half case body 101 is formed in the pivot portion 141 a.

  The first engagement / disengagement member 141 having the above configuration is a part of the characteristic part of the present invention. Due to its unique configuration, the first engagement / disengagement member 142 of the second engagement / disengagement member 142, which will be described later, can be simply assembled. In addition to inserting the pin 141d at the tip into the long hole 142b and easily attaching it to a predetermined position of the half case body 101, it can be easily attached, and the engaging / disengaging claw portion 141b can be attached as in the conventional case. A torsion spring for restraining the main spring barrel 130 in the direction of engagement with the outer peripheral ratchet teeth 130c is unnecessary, and the number of parts of the entire switching mechanism between the first start mode and the second start mode can be reduced. The mechanism can be simplified.

  As shown in FIG. 9, one of the second engaging / disengaging members 142 is entirely formed in a square shape, has a pivoting portion 142a at the center thereof, and has one end portion of the first engaging / disengaging member 141. A long hole 142b into which the pin 141d is inserted is formed. Further, the other end portion has an engagement / disengagement claw portion 142c protruding in the thickness direction of the second engagement / disengagement member 142. The first and second engaging / disengaging members 141 and 142 are pivotally mounted side by side at positions close to the upper wall surface of the half case body 101. The engagement / disengagement claw portion 141b of the first engagement / disengagement member 141 is engaged / disengaged with an outer peripheral ratchet tooth 130c formed on the outer peripheral surface of the mainspring barrel 130, and the engagement / disengagement claw portion 142c of the second engagement / disengagement member 142 is engaged with the ratchet. The second engagement / disengagement member 142 engages / disengages with the large-diameter first ratchet portion 121 by a torsion spring 144 while engaging / disengaging with the large-diameter first ratchet portion 121 of the wheel 120. Is being energized. Further, the first and second engaging / disengaging members 141 and 142 are pivotally attached to predetermined positions of the half case body 101 as described above, and the first engaging / disengaging member 141 is inserted into the elongated hole 142b of the second engaging / disengaging member 142. When the first pin 141d is inserted, the spring force of the leaf spring portion 141c of the first engagement / disengagement member 141 is always biased in a direction to engage with the ratchet wheel 120.

  In the present embodiment, as shown in FIG. 10, a turn which is an operation means for performing the engagement / disengagement operation of the second engagement / disengagement member 142 and the ratchet wheel 120 at the upper end portion of the half case body 101. A dynamic switch 143 is attached. As shown in FIGS. 3 and 10, the rotation switch 143 has a phase difference of approximately 130 ° from the knob 143b protruding in the radial direction from the disk-like pivoting portion 143a, and the radial switch from the disk-like pivoting portion 143a. And a bottom wall portion of the half case body 101 so as to face the upper surface of the end portion of the second engaging / disengaging member 142 on the side where the elongated hole 142b is formed. Is pivotally supported via a boss (not shown). Here, the pin 141d of the first engaging / disengaging member 141 is loosely inserted into the elongated hole 142b.

  Now, when the knob 143b of the rotation switch 143 is rotated from the left position indicated by the phantom line to the right side indicated by the solid line in FIG. 10, the trapezoidal protrusion 143c of the rotation switch 143 is disengaged from the second engagement / disengagement. The second engagement / disengagement member 142 is separated from the upper surface of the end of the member 142 on the side where the elongated hole 142b is formed, and the second engagement / disengagement member 142 is caused by the spring force of the torsion spring 144 and the leaf spring portion 141c of the first engagement / disengagement member 141. The ratchet teeth 121a are engaged. At the same time, the first engagement / disengagement member 141 is also engaged with the outer peripheral ratchet teeth 130 c of the mainspring barrel 130 by the spring force of the leaf spring portion 141 c of the first engagement / disengagement member 141.

  That is, when the rotation switch 143 is rotated clockwise as shown in FIGS. 10 and 11, the first and second engagement / disengagement members 141 and 142 respectively cause the outer ratchet teeth 130 c of the mainspring barrel 130 and the ratchet wheel. Engage with 120 large-diameter ratchet portions 121. This state is the second start mode, and when the recoil rope 115 is pulled and the recoil reel 116 is rotated in this state, the mainspring barrel 130 rotates in the direction of power accumulation, but the first engagement / disengagement member 141 and the outer ratchet teeth The rotation in the opposite direction is stopped because 130c is engaged. At this time, the ratchet wheel 120 of the rotation follower M receives a force in a direction to release the spring force of the power storing spring 131, but the second engagement / disengagement member 142 is engaged, so that the rotation stops at all. It has been. Therefore, when the recoil rope 115 is pulled and the recoil reel 116 is rotated, the mainspring barrel 130 rotates in the power storage direction, and only the power storage of the power storage spring 131 is performed exclusively with the ratchet wheel 120.

  Here, even if the pulling operation of the recoil rope 115 is stopped halfway and the hand is released from the recoil rope 115, the accumulated force is held between the mainspring barrel 130 and the ratchet wheel 120 as it is. Therefore, for example, in a place where a pulling operation by a weak person or a pulling operation of the recoil rope 115 can not be performed freely, the recoil rope 115 is pulled in several times and the engine is started in the energy storage spring 131. If the first and second engaging / disengaging members 141 and 142 are disengaged after switching to the first starting mode after storing sufficient spring force, the engine can be started instantly. Whether or not the accumulated force stored at this time has reached a sufficient force to start the engine can be surely known from the notification signal generated by the operation of the torque limit mechanism described above.

  In order to switch to the first start mode, when the rotation switch 143 is rotated from the position of the solid line shown in FIG. 10 to the position on the left side of the imaginary line, the length of the second engaging / disengaging member 142 is changed as shown in FIG. The trapezoidal protrusion 143c of the rotation switch 143 that is separated from the upper surface on the side where the hole 142b is formed is pressed against the upper surface of the main body on the side where the long hole 142b is formed, and the torsion spring 144 and the first engagement member are pressed. The second engagement / disengagement member 142 is rotated in the clockwise direction against the spring force of the leaf spring portion 141c of the removal member 141. By this rotation, the engagement between the second engagement / disengagement member 142 and the first ratchet portion 121 of the ratchet wheel 120 is released. At the same time, the repulsive force of the leaf spring portion 141c of the first engagement / disengagement member 141 acts, and the engagement between the engagement / disengagement claw portion 141b of the first engagement / disengagement member 141 and the outer peripheral ratchet teeth 130c of the spring barrel 130 is released. This state is the first start mode.

  Thus, in the second start mode, when the accumulator mainspring 131 has sufficient accumulating power to start the engine, the outer ratchet teeth 130c of the mainspring barrel 130 and the first ratchet portion 121 of the ratchet wheel 120 When the first start mode is switched to the disengaged mode, the engine can be started instantly. Here, when the rotational speed of the engine exceeds a predetermined speed, the hook-like engagement / disengagement member 107 of the centrifugal clutch mechanism attached to the fan 106 on the engine side receives a centrifugal force, and as shown in FIG. The engagement between the claw portion 107b and the small-diameter second ratchet portion 122 of the ratchet wheel 120 is released, and the rotation of the ratchet wheel 120 is automatically stopped, but the rotation of the engine is continued.

  By the way, the above explanation is based on the recoil when the second engagement / disengagement member 142 is engaged with the first ratchet portion 121 of the ratchet wheel 120 of the rotation follower M and the rotation in the direction of accumulated energy is prohibited. When the mainspring barrel 130 is rotated in one direction via the recoil reel 116 by pulling the rope 115 to store power in the power storage spring 131, and the stored power becomes sufficient to start the engine, The second engagement / disengagement member 142 is operated to release the engagement with the first ratchet portion 121 and switch to the first start mode, and the second ratchet portion 122 which is a centrifugal clutch mechanism and the hook-like engagement / disengagement member 107 are engaged. The case where the engine is started while maintaining the engagement has been described.

  However, for the skilled worker, starting the engine after previously performing the power storage operation of the power storage spring 131 as described above is often avoided because it hinders the efficiency of the work. In the present embodiment, when the knob 143b of the rotation switch 143 is in the first start mode in which the knob 143b is rotated from the solid line position in FIG. 10 to the virtual line position, the recoil rope 115 is pulled to remove the recoil reel 116. The mainspring barrel 130 is rotated by rotating it. Before the accumulator mainspring 131 is sufficiently accumulated to exceed the engine maximum load, it is engaged with the hook-shaped engagement / disengagement member 107 of the centrifugal clutch mechanism attached to the fan 106 of the engine. The two ratchet portion 122 has not been able to rotate the crankshaft 105 yet and has stopped, and the rotation of the ratchet wheel 120 has also stopped. Here, when a sufficient spring force that exceeds the maximum load of the engine is stored in the energy storage spring 131, the ratchet wheel 120 is automatically rotated in the direction of releasing the energy storage, and the engine power is transmitted via the centrifugal clutch mechanism. The crankshaft 105 rotates to start the engine.

  If the pulling operation of the recoil rope 115 is stopped in the middle of this power accumulation, the mainspring barrel 130 and the ratchet wheel 120 are not engaged with the first and second engaging / disengaging members 141, 142. Then, the mainspring barrel 130 starts to reverse, and the spring force of the power storage mainspring 131 that has been stored up to then is automatically released. At this time, the spring force and shape of the first engagement / disengagement member are designed so that the ratchet wheel 120 starts reversing slightly earlier than the reversal of the mainspring barrel 130, and the rotational force of the ratchet wheel 120 is applied to the crankshaft. After a sufficient transmission, the mainspring barrel 130 starts to reverse. As a result, the stored power remaining in the stored power spring 131 after the engine has been started is naturally released, and there is no fear that the engine will be inadvertently started.

  In this embodiment, in order to improve the durability of the ratchet wheel 120, the shape of the ratchet teeth 121a of the first ratchet portion 121 is also improved. Usually, the ratchet teeth of this type of ratchet wheel are made in the shape of a flat right triangle having an engagement surface that rises radially outward from the wheel body. With the ratchet teeth having such a shape, even if the ratchet wheel and the ratchet claw portion to be engaged with and disengaged from the ratchet wheel are made of metal, the ratchet teeth 121a are increased as the number of engagement / disengagement with the second engagement / disengagement member 142 increases. Wear occurs on the engagement / disengagement surface of the ratchet and the engagement / disengagement surface of the ratchet pawl, and the engagement is disengaged even if a slight impact is applied. Further, when the claw portion of the second engagement / disengagement member 142 hits a corner portion formed between the rising base end portion of the engagement / disengagement surface of the ratchet tooth 121a and the main body of the ratchet wheel 120, the ratchet wheel A crack toward the center side of 120 may occur. In order to solve these problems, the surface of the ratchet teeth 121a and the ratchet pawls, in particular, has been subjected to a surface treatment such as nitriding on the engagement / disengagement surface to increase the surface hardness and avoid wear. However, the above problem has not been solved at all.

  Therefore, in the present embodiment, as shown in FIG. 4, the engagement / disengagement surface of the ratchet tooth 121a of the first ratchet portion 121 is inclined outward from the radial direction to the engagement / disengagement side with a predetermined inclination angle α. At the same time, a notch 121b having a required length is formed toward the center of the wheel at a corner formed between the rising base end of the ratchet tooth 121a and the wheel body. Yes. Since the engagement / disengagement surface of the ratchet tooth 121a is tilted from the radial direction toward the engagement / disengagement side with a predetermined inclination angle α, the base side of the engagement / disengagement surface is inclined at an inclination angle even if the tooth tip portion is worn. Due to α, the engaging / disengaging claw portion of the other party is surely gripped and locked at the time of engagement, and is not easily detached. Further, since the notch 121b is formed at the corner formed between the rising base end of the ratchet tooth 121a and the wheel body, the impact force acting on the corner is notched 121b. And the generation of cracks is eliminated, and the durability is further increased.

  When the second engaging / disengaging member 142 is manufactured from sheet metal by press working, as shown in FIG. 9, the other end opposite to the different end portion where the long hole of the second engaging / disengaging member 142 is formed. Is bent at a right angle to form the engaging claw 142c. By doing so, the engagement width of the engaging portion with the ratchet teeth 121a of the mating first ratchet portion 121 can be increased by the bent length of the engaging / disengaging claw portion 142c, and the first ratchet direction can be increased. In the engagement portion between the portion 121 and the engagement / disengagement claw portion 142c, the movement in the crank axis direction can be allowed to some extent, so that the engagement can be prevented from being released by a slight external force. In addition, when the second engagement / disengagement member 142 and the first ratchet part 121 are made of metal, if the material of the second engagement / disengagement member 142 is made lower in hardness than the material of the first ratchet part 121, The engagement / disengagement member side wears due to repeated use, and the wear also wears into a shape in which the engagement with the first ratchet portion 121 regulates the movement in the crank axis direction. It will be something.

It is a disassembled perspective view which shows the example of arrangement | positioning of the structural member of the engine starting apparatus which is typical embodiment of this invention. It is a longitudinal cross-sectional view which shows the example of an assembly structure of the engine starting device and a small engine. It is a perspective view which shows the structure of the rotation follower of the engine starter. It is a rear view of the ratchet wheel in the rotation follower. It is the perspective view which looked at the ratchet wheel from the back side. It is the front view seen from the engine side which partially shows the mainspring barrel of the buffering / accumulating part of the engine starting device. It is the perspective view which looked at the said mainspring barrel from the back side. It is a three-dimensional view of the 1st engagement / disengagement member engaged / disengaged with the outer periphery ratchet teeth of the mainspring barrel. It is a three-dimensional view of the 2nd engagement / disengagement member engaged / disengaged with the 1st ratchet part of the said ratchet wheel. It is explanatory drawing of the start mode switching operation in the said embodiment. It is the front view seen from the engine side which shows the state of the 1st and 2nd engagement / disengagement member when it exists in the 2nd start mode. It is the front view seen from the engine side which shows the state of the 1st and 2nd engagement / disengagement member when it exists in the 1st start mode.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Engine starter 101 Half case body 101a Cylindrical boss part 102 Set screw 105 Crankshaft 106 Fan 106a Pivoting part 106b Set screw 107 Hook-like engaging / disengaging member 107a Hook-like engaging / disengaging part main body 107b Claw part 110 Recoil spring 110a Outer hook End 112 Circular hole 113 Mainspring case 114 Grip 115 Recoil rope 116 Recoil reel 116a Engaging / disengaging claw rod 120 Ratchet wheels 121, 122 First and second ratchet portions 121a, 122a Ratchet teeth 123 Circular protrusion 123a (U-shaped ) Notch groove 130 Mainspring barrel 130a Mainspring housing portion 130b Protruding portion 130b-1 Engaging surface 130b-2 Apex portion 130b-3 Inclined surface 130c Outer peripheral ratchet teeth 131 Power saving spring 131a Outer hook portion 131b Inner hook portion 132 Small ratchet portion 132a Ratchet teeth 133 Annular cover 141, 142 First and second engaging / disengaging member 141a Pivoting portion 141b Engaging / disengaging claw portion 141c Leaf spring portion 141d Pin 142a Pivoting portion 142b Long hole 142c Engaging / disengaging claw Part 143 Rotation switch 143a Pivoting part 143b Knob part 143c Trapezoidal protrusion 144 Torsion spring D Rotation drive part M Rotation driven part O, O 'Center α Ratchet tooth inclination angle

Claims (7)

A rotation drive unit, a buffer / accumulation means for accumulating power while buffering the driving force of the drive unit, and a rotation follower for starting the engine by releasing the accumulated force of the buffer / accumulation means,・ When the stored power stored in the power storage means is the stored power necessary for starting the engine, the stored power is released and transmitted to the rotation follower, and the engine is started via the rotation follower. In the engine starter,
A first engagement / disengagement member that engages / disengages the buffer / accumulation means to prevent / allow reversal of the buffer / accumulation means, and a switching operation means that engages / disengages the first with the buffer / accumulation means And having
The first engaging / disengaging member is made of an elastic member.
An engine starter characterized by that.   The first engagement / disengagement member has, at one end thereof, a pivot attachment portion pivotably attached to the case body of the engine starter, and an engagement / disengagement claw portion extending from the pivot attachment portion, 2. The engine start according to claim 1, wherein a leaf spring portion is extended on the opposite side across the pivot attachment portion, and a pin parallel to the axis of the pivot attachment portion projects from the tip of the leaf spring portion. apparatus. In addition, a second engagement / disengagement member that is engaged with and disengaged from the first engagement / disengagement member and engages / disengages with the rotary drive unit is provided. It has a pivot part pivotally attached to the cover of the device, and has an engagement / disengagement claw part on one end side thereof, and a long hole is formed on the other end part. Urged in a direction to engage with the rotation follower,
The pin of the first engagement / disengagement member is inserted into the elongated hole of the second engagement / disengagement member, and the pin is biased in a direction to engage with the buffer accumulation means by the spring force of the leaf spring part.
The engine starter according to claim 2.   The switching operation means rotates the second engagement / disengagement member against its bias to release the engagement with the rotation follower, and receives the rotation of the second engagement / disengagement member. The first engaging / disengaging member is made to slide by sliding the pin of the first engaging / disengaging member in the long hole of the second engaging / disengaging member to rotate the first engaging / disengaging member against the spring force of the leaf spring portion. 4. The engine starting device according to claim 3, further comprising an operation member for releasing the engagement between the engagement / disengagement claw portion and the buffer / accumulation means.   5. The engine starter according to claim 4, wherein the operation member is pivotally attached to a cover of the engine starter so that a cam surface is formed on a surface facing the second engaging / disengaging member. . The spring / accumulation part has a mainspring barrel in which the first engagement / disengagement member is engaged / disengaged, and an energy storage spring in which one end is supported by the incense box and the other end is supported by the rotation follower,
The rotation follower has a ratchet wheel that engages and disengages with the second engaging / disengaging member.
The engine starting device according to any one of claims 1 to 5.   The engine starter according to claim 1 or 2, further comprising a torque limit mechanism that operates when the power accumulated by the buffering / power accumulation means exceeds a load necessary for engine start.

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