JPH0643828B2 - Engine starter - Google Patents

Description

Detailed Description of the Invention A. OBJECT OF THE INVENTION (1) Field of Industrial Use The present invention relates to an engine starting device, and in particular, an output shaft rotatably driven by a starting motor is rotatably and immovably supported in a housing, and the output shaft At the tip, a pinion gear that advances and retreats in the axial direction so as to be disengaged from the ring gear of the engine is slidably fitted via a spline, and is connected to this pinion gear, and a moving rod that penetrates the center of the output shaft,
An electromagnetic device capable of shifting this in the forward direction of the pinion gear is connected, and further, the moving rod is slidably engaged with a guide hole provided in the output shaft and abuts against the inner end wall of the guide hole to regulate the forward limit of the pinion gear. The present invention relates to a starting device of the type in which a stopper member is provided, and a return spring for biasing the moving rod in the backward direction via the stopper member is provided between the inner end wall of the guide hole and the stopper member.

(2) Prior Art Such a starting device is disclosed in Japanese Patent Application Laid-Open No. 57-148056.

(3) Problems to be Solved by the Invention In the engine starting device disclosed in the above publication, the return spring for the moving rod is arranged so that the pinion gear (and therefore the moving rod) starts to move forward smoothly with the operation of the electromagnetic device. Since the spring force is set to be relatively weak, this return spring cannot be effectively used as a cushioning means when the pinion gear reaches the forward limit, that is, when the pinion gear reaches the forward limit, the stopper member acts as an output shaft. However, there is a problem in that noise is generated by impacting the inner wall of the guide hole.

The present invention has been proposed in view of the above, and when the pinion gear reaches the forward limit, the stopper member can be slowly brought into contact with the inner end wall of the guide hole of the output shaft to solve the noise problem of the conventional device. (EN) Provided is an engine starting device having a simple structure that can effectively solve a problem that noise is generated at a meshing portion of a pinion gear and a ring gear due to torque fluctuation during engine cranking. With the goal.

B. Configuration of the Invention (1) Means for Solving the Problems In order to achieve the above object, the present invention provides a starter for an engine of the type described above, wherein a pinion gear is provided between an inner end wall of the guide hole and a stopper member. Is a return spring, which is a buffer spring for performing a buffering operation until the forward limit is reached after a predetermined meshing state with the ring gear is reached and for causing the stopper member to abut the guide hole inner end wall slowly. In contrast, the spline is formed in a helical shape so as to generate an axial component force that pushes the pinion gear in the forward direction while giving a buffering action to the buffer spring when the output shaft is driven. It is characterized by

The buffer spring may be made of metal or rubber.

(2) Operation According to the above configuration, when the moving rod is moved forward by the operation of the electromagnetic device, the pinion gear can be quickly moved forward and meshed with the ring gear of the engine without being restrained by the buffer spring at the beginning. .

Then, when the pinion gear enters a predetermined meshing state with the ring gear and the driving torque is applied from the output shaft to the pinion gear by the operation of the starting motor, the buffer spring effectively exhibits the buffer function. Therefore, the stopper member is brought into contact with the inner end wall of the guide hole slowly without impact, so that the forward limit of the pinion gear can be quietly controlled, and the engine torque during cranking can be reduced. If there is fluctuation, the pinion gear moves forward and backward in the meshed state with the ring gear accordingly, and accordingly, the shock absorbing member can exert a shock absorbing function to absorb the torque fluctuation.

(3) Examples Hereinafter, examples of the present invention will be described with reference to the drawings.
First, in FIG. 1 showing a first embodiment of the present invention, a transmission housing generally designated by reference numeral H comprises a front housing 1 and a rear housing 2 which are detachably joined to each other. And an electromagnetic switch S (corresponding to the electromagnetic device of the present invention) for activating it are mounted in parallel with each other as follows.

That is, the stator 3 of the starting motor M and the rear bearing bracket 4 are sequentially stacked on the rear surface of the rear housing 2, and they are fixed to the front housing 1 by the bolts 5 together with the rear housing 2. The rotor shaft 6 of the starting motor M is supported by the rear housing 2 and the bearing bracket 4 via a ball bearing 7 and a bearing bush 8, respectively, and the output end, that is, the front end of the rotor shaft 6 projects into the transmission housing H. ing.

In the electromagnetic switch S, a switch cylinder 10 holding a solenoid 9 is fixed to the rear housing 2 with screws 11. Inside the solenoid 9, a fixed iron core 13 connected to the switch cylinder 10 via a yoke 12 and a movable iron core 14 that moves forward and backward with respect to the front surface thereof are arranged.
A return spring 15 for urging the movable iron core 14 in a direction separating from the front surface of the fixed iron core 13 is contracted between the members 14. The movable iron core 14 has a switch operating rod 1 penetrating the fixed iron core 13.
6 is integrally formed, and a movable contact 17 is slidably attached to the tip thereof, and the movable contact 17 is normally held at the tip position of the switch operating rod 16 by the elastic force of the compression spring 18. . A terminal cap 19 made of an insulating material is fixed to the rear end of the switch cylinder 10, and a pair of terminal bolts 20 penetrating the end wall of the switch cylinder 10 is fixed to the inner end of the bolts 20. A pair of fixed contacts 21 facing the movable contact 17 are formed. One of the pair of terminal bolts 20 has a conductive wire connected to the power source,
Conductors (not shown) connected to the starting motor M are connected to the other, respectively.

Further, the movable iron core 14 is also integrally formed with an operating rod 22 with a hook 22a that projects into the transmission housing H.

In the transmission housing H, an output shaft 23 that is parallel to the rotor shaft 6 and the operating rod 22 at an intermediate position, and a one-way transmission device that transmits a driving force from the rotor shaft 6 to the output shaft 23 in one direction. And the output shaft 23 has ball bearings 24, 2 on the front and rear housings 1, 2 respectively.
It is rotatably supported via 5 and cannot move in the axial direction.

The one-way transmission device T includes a driven gear 27 having a small-diameter drive gear 26 formed at the output end of the rotor shaft 6 and a large-diameter driven gear 27 concentric with the output shaft 23 and meshing with the drive gear 26.
And a one-way clutch C interposed between the output shaft 23 and the one-way clutch C. The one-way clutch C is integrally provided with the driven gear 27 on the outer periphery and has a pair of bearing bushes 2.
A clutch outer 30 rotatably supported by the output shaft 23 via 8, 29, a clutch inner 31 integrally formed on the outer peripheral portion of the output shaft 23 and disposed in the clutch outer 30, and the clutches thereof. Outer and inner 30,3
The wedge roller 32 is interposed between the two rollers. Thus, the one-way clutch C has a one-way transmission function of transmitting torque from the clutch outer 30 or the driven gear 27 to the clutch inner 31 or the output shaft 23 but interrupting reverse load transmission as usual. To have.

The output end of the output shaft 23 projects to the front surface of the front housing 1, and the cylindrical boss 33a of the pinion gear 33 is fitted on the outer periphery of the output end of the output shaft 23 so as to be slidable back and forth via a helical spline 34 (see FIG. 5). Are combined. At a predetermined forward position of the pinion gear 33, an engine ring gear 35 meshing with the pinion gear 33 stands by. Above helical spline 3
4 is when the output shaft 23 drives the pinion gear 33,
It has a lead angle that can generate an axial component force that pushes the pinion gear 33 in the forward direction, that is, the direction in which it meshes with the ring gear 35.

The output end of the output shaft 23 extends forward beyond the axial centerline L of the ring gear 35. This prevents the pinion gear 33 from tilting due to its driving reaction force when the pinion gear 33 drives the ring gear 35. Gears 33 and 35
The proper meshing state of is maintained.

The open front surface of the cylindrical boss 33a of the pinion gear 33 is closed by a dustproof plate 37 which is caulked and fixed to the pinion gear 33, thereby preventing dust and the like from entering the boss 33a.

The pinion gear 33 is shifted to a meshing position with the ring gear 35 when the electromagnetic switch S is operated, and a pinion moving device D for that purpose is provided in the transmission housing H as follows.

The pinion moving device D has a moving rod 38 that slidably penetrates through the shaft center portion of the output shaft 23. At the front end of the moving rod 38, the dustproof plate 37 of the cylindrical boss 33a and the boss 33 thereof are provided.
A pressing flange 38a that can move forward and backward is formed between the retaining ring 36 and the retaining ring 36 that is engaged with the inner wall of the flange 3a.
A barrel-shaped buffer coil spring 39 is contracted between 8a and the dustproof plate 37.

The rear portion of the hollow portion of the output shaft 23 is enlarged to form a guide hole 40, and a cylindrical stopper member 41 that slides into the guide hole 40.
Is fixed on the moving rod 38 by a retaining ring 42, and a return coil spring 43 for urging the moving rod 38 in the backward direction via a flange 41a formed on the outer periphery of the rear end of the stopper member 41.
Is contracted to the guide hole 40.

As shown in FIG. 2, the flange 41 of the stopper member 41
A notch 44 is provided on the outer peripheral surface of a, and this is a guide hole 40.
And a ventilation hole that communicates with each inside of the transmission housing H.
Therefore, the stopper member 41 can slide in the guide hole 40 without being resisted by the air therein.

The stopper member 41 has the front end thereof at the inner end wall 4 of the guide hole 40.
By contacting 0a, the forward limit of the pinion gear 33 is regulated, and a bottomed spring accommodating hole 51 whose one end is opened to the guide hole 40 is formed on the inner periphery of the stopper member 41. A buffer spring 52 is provided in the spring accommodating hole 51.
Are mounted on the return spring 43 substantially concentrically.

As shown in FIG. 5, the buffer spring 52 is provided in the guide hole 40.
The tip is projected into the guide hole 40 with a predetermined space 1 between the inner end wall 40a and the inner end wall 40a. The interval 1 corresponds to the moving stroke from the backward movement of the pinion gear 33 to the predetermined engagement with the ring gear 33.

As shown in FIG. 6, the buffer spring 52 has a spring constant larger than that of the return spring 43 and can exert a repulsion larger than the forward force of the moving rod 38 by the operation of the electromagnetic switch S. The force is smaller than the axial component force exerted on the pinion gear 33 by the helical spline 34 when the output shaft 23 is driven.

Further, as shown in FIG. 4, the pinion moving device D has a lever holder 45 fixed to the transmission housing H.
And a shift lever 47 pivotally supported by the pivot pin 46, and an overload spring 48 formed of a torsion coil spring wound around the outer periphery of the pivot pin 46. Then, the shift lever 47 engages the rear end of the moving rod 38 with the first arm 4
7a and a bifurcated second arm 47b that sandwiches the pivot pin 46 and extends in the opposite direction.
First and second locking arms 48a and 48b of the overload spring 48 are locked to the rear surfaces of a and 47b, respectively. At that time, a predetermined torsion torque is applied as a set load to the coil portion of the spring 48, and the second locking arm 48b is bridged between the two forked second arms 47b of the shift lever 47, and the bridge portion has the above-mentioned operation. The hook 22a of the rod 22 is locked and connected. In the above, the effective length of the second locking arm 48b of the spring 48 is the lever 47.
Is shorter than that of the first arm 47a. Therefore, the movement of the operating rod 22 can be accelerated and transmitted to the moving rod 38 by the ratio of the arm lengths.

The retracted positions of the pinion gear 33, the moving rod 38, and the shift lever 47 by the action of the return spring 43 are restricted by the back surface of the first arm 47a of the shift lever 47 contacting the stopper portion 2a formed on the inner wall of the rear housing 2. It

A pinion housing 49 that receives the rear half of the pinion gear 33 retracted from the ring gear 35 is continuously provided at the front end of the transmission housing H, and an inlet 49a of the pinion housing 49 is widened outward to extend the pinion gear 33. It is designed to guide the storage in the pinion housing 49. Rainwater, washing water, and the like that have entered the inlet 49a are guided to the tapered surface of the inlet 49a and quickly discharged to the outside of the lower portion.

Further, the pinion housing 49 has a drain hole 50 which communicates the inside with the outside below the inlet 49a, and the drain hole 50 has a downward slope toward the outlet. Therefore, even if water should enter the pinion housing 49, it can be immediately drained from the drain hole 50.

On the other hand, at the rear end of the pinion gear 33, a closing wall 33b that integrally connects the respective teeth is formed, and this closing wall 33b prevents water from entering the inside of the pinion housing 49 through the teeth of the pinion gear 33. Also, it is useful for reinforcing the teeth of the pinion gear 33.

Next, the operation of this embodiment will be described. When the engine start switch is operated to energize the solenoid 9 of the electromagnetic switch S, the movable iron core 14 is attracted to the fixed iron core 13 and the operating rod 22 is overloaded. The shift lever 47 is rotated around the pivot pin 46 in the counterclockwise direction in FIG. 1 via the load spring 48, and the first arm 47a causes the moving rod 38 to move forward against the force of the return spring 43. (To the left in Figure 1)
Push. When the moving rod 38 is moved forward, the pressing flange 38 a moves the pinion gear 33 forward to the meshing position with the ring gear 35 via the buffer spring 39. At this time,
If the tooth traces of both gears 33 and 35 do not match and the tooth flanks collide, the moving rod 38 leaves the pinion gear 33 at the collision position, and the buffer spring 39 is compressed to prevent dust. The movable iron core 14 moves forward to the abutting position with the plate 37, retracts to the close contact position with the fixed iron core 13 while twisting the overload spring 48, and the elastic deformation of the both springs 39, 48 causes the gears 33, 35 to move. The shock from a collision is absorbed.

On the other hand, the movable contact 17 comes into contact with the pair of fixed contacts 21 almost at the same time that the movable iron core 14 is attracted to the fixed iron core 13, and energizes the starting motor M to activate it.

Then, according to the rotation of the rotor shaft 6, the output shaft 23 is decelerated by the driving gear 26 and the driven gear 27, and further via the one-way clutch C, so that the output shaft 23 produces a large driving torque. The pinion gear 33 is rotated.

In the initial rotation of the pinion gear 33, the ring gear 3
When 5 and the tooth trace match, the pinion gear 33 moves forward by the elastic force stored in the overload torsion coil spring 48 and enters a meshing state with the ring gear 35.

At this time, first, the buffer spring 5 is moved by restarting the forward movement of the moving rod 38.
2 comes into contact with the inner end wall 40a of the guide hole 40 to reduce the moving impact of the moving rod 38. Next, when a drive torque is applied to the pinion gear 33 from the output shaft 23 via the helical spline 34, the pinion gear 33 moves to the helical spline 34.
Is moved forward together with the moving rod 38 and the stopper member 41 by the axial component force generated in step S3, compressing the return spring 43 and the buffer spring 52, and moving the stopper member 41 to the inner end wall 40 of the guide hole 40.
It is brought into contact with a and the forward movement of the pinion gear 33 is stopped.
As a result, the stopper member 41 comes into contact with the guide hole inner end wall 40a slowly. The rotation of the pinion gear 33 is delayed by the amount of forward movement of the output shaft 23, and the shock-absorbing drive torque of the output shaft 23 is absorbed by the buffer spring 52 during that time. Therefore, the pinion gear 33 drives the ring gear 35 without causing shock. Then, the crankshaft of the engine can be cranked.

If torque fluctuation occurs in the crankshaft during cranking of the engine, the pinion gear 33 moves back and forth in the axial direction accordingly, and the buffer spring 52 expands and contracts to absorb the torque fluctuation.

From the above, as shown in the test results of FIG. 8, the noise level (A) of the device of the present invention is the noise level (B) of the conventional device.
Than in the peak value.

FIG. 7 shows a second embodiment of the present invention. Prior to the stopper member 41, an abutting member 60 capable of abutting against the inner end wall 40a of the guide hole 40 is slid into a spring accommodating hole 51 of the stopper member 41. The configuration is the same as that of the previous embodiment except that the stopper ring 61 regulates the forward movement of the contact member 60 with respect to the stopper member 41 to apply a predetermined set load to the buffer spring 52. The parts corresponding to those in the previous embodiment are designated by the same reference numerals.

When the engine is started, the ring gear 35 rotates at a high speed, and the pinion gear 3 rotates at a speed faster than the rotation of the driven gear 27.
If 3 is driven, the one-way clutch C is disengaged and the reverse load of the ring gear 35 is not transmitted to the starter motor M side, and the overrun can be prevented.

When the start switch is turned off after the start, the movable iron core 14 of the electromagnetic switch S is returned to the initial position by the elastic force of the return spring 15, and the movable contact 17 is separated from the fixed contact 21 to deactivate the start motor M. At the same time, the moving rod 38 retreats by the elastic force of the return spring 43, disengages the pinion gear 33 from the ring gear 35, and stores it in the pinion housing 49.

C. EFFECTS OF THE INVENTION As described above, according to the present invention, between the inner end wall of the guide hole and the stopper member, the pinion gear performs a buffering operation from a predetermined meshing state with the ring gear until the forward limit is reached. A buffer spring for gently contacting the stopper member with the inner end wall of the guide hole is interposed substantially concentrically with the return spring compressed between the inner end wall of the guide hole and the stopper member. Since the spline between the tip of the output shaft and the pinion gear is formed in a helical type so as to generate an axial component force that pushes the pinion gear in the forward direction while giving a buffering action to the buffer spring when the output shaft is driven, When the moving rod is moved forward by the operation of the device, the pinion gear is initially not restrained by the buffer spring and can move forward quickly and lightly so as to be quickly meshed with the ring gear of the engine. Then, since the pinion gear enters a predetermined meshing state with the ring gear and the driving torque is applied to the pinion gear from the output shaft by the operation of the starting motor, the buffer spring can effectively exert the buffering function. The contact with the inner wall of the hole can be done slowly without impact, and the forward limit of the pinion gear can be controlled quietly at all times, and if torque fluctuation occurs in the engine during cranking of the engine, Accordingly, since the pinion gear advances and retreats in the axial direction in the meshed state with the ring gear, the cushioning function can be exerted by the cushioning member according to the advance and retreat, and the above torque fluctuation can be effectively absorbed. It can greatly contribute to the reduction of the amount of noise generated when starting the engine and the improvement of the durability of the starting device.

Moreover, since the buffer spring is housed in the guide hole of the output shaft substantially concentrically with the return spring, the buffer spring can be easily installed without major modification to the conventional device. If both the return spring and the return spring are formed to have a relatively large diameter so that they can be accommodated comfortably, the weight of the output shaft can be increased and the weight thereof can be reduced.

Further, as described above, the buffer spring slowly moves the stopper member into contact with the inner wall of the guide hole so as to quietly control the forward limit of the pinion gear. Since it is also used as a torque fluctuation reducing means that absorbs the torque, the stopper member also serves as a retainer for the return spring and the buffer spring, which greatly contributes to downsizing of the device and simplification of the structure. You can

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of a main part showing a first embodiment of the present invention, FIGS. 2 and 3 are views taken along line II-II and III-III of FIG.
FIG. 4 is an exploded perspective view of a main part thereof, FIG. 5 is an enlarged view of the main part of FIG. 1, FIG. 6 is a characteristic diagram of a return spring and a buffer spring,
FIG. 7 is an enlarged view similar to FIG. 5 showing a second embodiment of the present invention, and FIG. 8 is a noise level comparison diagram of the present invention device (A) and the conventional device (B). H ... Transmission housing, M ... Starting motor, S ... Electromagnetic switch as electromagnetic device, 33 ... Pinion gear, 34 ... Helical spline,
35 ... Ring gear, 38 ... Moving rod, 40 ... Guide hole, 40a ... Inner end wall, 41 ... Stopper member, 43 ...
... Return spring, 51 ... Spring accommodating hole, 52 ... Buffer spring

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Eiichi Kimura 1-2681 Hirosawa-machi, Kiryu-shi, Gunma Prefecture Mitsuba Electric Manufacturing Co., Ltd. (56) References JP 57-148056 (JP, A) 18-9831 (JP, Y1)

Claims (1)

[Claims] 1. An output shaft (23) rotatably driven by a starter motor (M) is rotatably and immovably supported in a housing (H), and an output shaft (23) has a tip end of an engine. A pinion gear (33) that advances and retreats in the axial direction so as to be disengaged from the ring gear (35) is slidably fitted via a spline (34), and is connected to the pinion gear (33) to connect the pinion gear (33) to the central portion of the output shaft (23). Moving rod (38)
To an electromagnetic device (S) capable of shifting the pinion gear (33) in the forward direction of the pinion gear (33).
8) A stopper member which is slidably engaged with a guide hole (40) provided in the output shaft (23) and abuts on an inner end wall (40a) of the guide hole (40) to restrict the forward limit of the pinion gear (33). (41) is provided, and a return spring (43) for urging the moving rod (38) in the backward direction via the stopper member (41) is provided with an inner end wall (40a) of the guide hole (40) and the stopper member. In an engine starting device which is contracted between the pinion gear (33) and an inner end wall (40a) of the guide hole (40) and the stopper member (41).
During a predetermined meshing state with the ring gear (35) until reaching the forward limit, a buffering operation is performed to prevent the stopper member (41) from contacting the inner end wall (40a) of the guide hole (40). A buffer spring (52) for performing the operation slowly is interposed substantially concentrically with the return spring (43), and the spline (34) is connected to the buffer spring (5) when the output shaft (23) is driven.
A starting device for an engine, characterized in that it is formed in a helical type so as to generate an axial component force for pushing the pinion gear (33) in the forward direction while giving a buffering action to 2).