JPS6390666A - Starter for engine - Google Patents

Abstract

PURPOSE:To improve quality of mounting to an engine, by a method wherein shaft parts are arranged in series, and a recessed part for bearing and a recessed part for fixed contact are formed in the rear bracket of an electric motor. CONSTITUTION:The shaft parts of an electric motor, generating a rotation force for starting an engine during energization, a pinion mechanism, transmitting the rotation force to an engine through a pinion 20, mounted to the one end of an output rotary shaft 17, and an electromagnetic switch 25, exerting a thrust force for moving the output rotary shaft 17 and bringing the electric motor into an energized state, are disposed in series. In which case, a rotary shaft 3 of the armature of the electric motor formed in a tubular manner, and a sleeve bearing 33, pivotally supporting the rear part of the output rotary shaft 17, is engaged with the inner peripheral surface of a pipe. A rear bracket 7 of the electric motor is molded by using plastic, a recessed part 7d for a bearing, with which to engage a bearing 8 pivotally supporting the rear part of the rotary shaft 3 of the armature, is formed in the front part of the rear bracket, and a recessed part 7b, internally of which a fixed contact 40 is situated, is formed in a range of from the rear end part to the front part of the rear bracket. This constitution enables reduction of the overall length and the size of a device, and decrease of the weight thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Utilization Denominator] The present invention relates to an engine starter used for an automobile engine or the like, and particularly to an improvement of one incorporating a planetary gear reduction device.

[Conventional technology]

Conventionally, an example of this type of starter incorporating a planetary gear reduction device is shown in FIG. 2. In the figure, 100 is an armature of a DC motor, which is composed of the elements described below. 101 is armature core, 1
02 is an armature rotating shaft with an armature core 101 provided in the middle part, and a commutator 103 is fitted into the rear part of the armature 100. An armature coil 104 wound around an armature core 101 is connected to this commutator 103.

Reference numeral 105 denotes a brush and a retainer that come into contact with the commutator 103, and are connected to the rear bracket 107 with bolts 106. A bearing 108 supports the armature rotating shaft 102 at its rear end, and is fitted into a recess of the rear bracket 107.

109 is a yoke of a DC motor, and a plurality of permanent magnets 109a that generate a field in the armature 100 are fixedly installed on the inner peripheral surface, and the end surface of the yoke 109 has internal teeth constituting a planetary gear reduction device. A front bracket 111 with a gear 110 fitted thereon is attached as shown. Armature rotating shaft 1
A spur gear 112 is formed at the front end of 02, and a plurality of planetary gears 113 mesh with both this and the internal gear 110.

A bearing 114 is fitted onto the inner circumferential surface of the planetary gear 113, and is supported by a support pin 115. Reference numeral 116 denotes a flange to which this support bin 115 is fixed, and constitutes an arm of the planetary gear reduction device, and an output rotating shaft 117 is placed at the rear. A sleeve bearing 118 is fitted onto the inner circumferential surface of the protrusion of the internal gear 110, and supports the output rotating shaft 117. 119 is the output rotation shaft 117
This sleeve bearing is fitted into a recess on the rear inner circumferential surface of the armature rotating shaft 102, and supports the front end of the armature rotating shaft 102.

120 is a steel ball disposed between both ends of the armature rotation shaft 102 and the output rotation shaft 117 and has the function of transmitting and receiving thrust. 121 is a helical ball formed on the outer periphery of the intermediate portion of the output rotation shaft 117. Overrunning clutch 1 with spline teeth
22 is spline-fitted so as to be slidable back and forth. 12
3 is an output shaft 117 that regulates the amount of axial movement of the pinion 124 connected to the overrunning clutch 122;
125 is a sleeve bearing that supports the output rotating shaft 117 at the front end;
It is fitted onto the inner surface of the front end of the front bracket 111.

Reference numeral 126 denotes a lever molded from plastic resin and having a rotating shaft 126a in the middle part, and is connected to the electromagnetic switch 12.
7 plunger 128 and overrunning clutch 12
129 is a movable contact, which is attached to the rod 131 via an insulator 130, and the rod 131 is slidably attached to the rod 113 so as to be able to slide back and forth.
It is inserted in 2. 133 is a fixed contact, nut 13
4, it is fixed to a cap 135 which is an insulator. Reference numeral 136 designates an excitation coil that energizes the plunger 128, which is wound around a bobbin 137 made of plastic resin and is housed in a case 138. A lead wire 139 connects the fixed contact 133 and the brush of the brush and retainer 105.

Next, the operation will be explained. By closing a starter switch (not shown), the excitation coil 136 of the electromagnetic switch 127 is energized, and the plunger 128 is energized and moves backward to push the rod 131 backward, causing the movable contact 1
29 and the fixed contact 133 are brought into contact. As a result, power is supplied to the armature 100 from the fixed contact 133 via the lead wire 139, the brush and the retainer 105, and the armature 100 generates rotational force. The rotation of the W machine 100 is transmitted from the spur gear 112 to the planetary gear 113, and is then decelerated by the planetary gear reduction mechanism and transmitted to the overrunning clutch 122. At this time, the pinion 124 engaged with the overrunning clutch 122 is rotationally driven.

On the other hand, the force of the plunger 128 biased as described above rotates the lever 126 in the counterclockwise direction about the rotating shaft 126a, causing the overrunning clutch 12 to rotate.
2 along with the pinion 124 forward along the axis. As a result, the pinion 124 meshes with, for example, a ring gear fixed to a flywheel attached to the crankshaft of an engine (not shown).

After the engine starts, the overrunning clutch 1
22 is separated from the pinion 124, and only the pinion 124 idles.

[Problem that the invention seeks to solve]

Conventional engine starters are configured as described above, so the electromagnetic switch and the DC motor body are configured with parallel shafts, and when installed on the engine, the space for the SM switch is reduced by excluding the engine or engine section. It is necessary to secure it on the vehicle side, which causes problems such as restrictions on the engine layout in the vehicle.Also, in order to prevent the tip of the front bracket from interfering with, for example, the flywheel inside the engine transmission housing, There were problems such as the shape of the flywheel being limited.

This invention was made to solve the above-mentioned problems.The electromagnetic switch and the electric motor are connected in series and are compactly configured. Furthermore, the bearing of the output rotating shaft can be configured in a cantilevered manner, making it easy to install. The purpose is to obtain an excellent engine starter.

[Means for solving problems]

The engine starter according to the present invention includes an electric motor having a tubular armature rotation shaft, a pinion mechanism that transmits the rotational force of the electric motor to the engine side through a pinion provided on the output rotation shaft at the time of engine starting, and a rotational force generated when the starter switch is turned on. Each shaft part of an electromagnetic switch is arranged in series to apply thrust to the output rotation shaft to move the output rotation shaft forward by electromagnetic force, and to turn on a switch having a moving contact and a fixed contact to energize the electric motor. In this engine starter, the output rotating shaft is cantilevered by providing a sleeve bearing for supporting the output rotating shaft on the inner peripheral surface of the tubular armature rotating shaft, and the rear bracket of the electric motor is made of plastic, and the rear The front part of the bracket is provided with a recess into which a bearing for supporting the rear part of the armature rotating shaft is fitted, and a recess into which a fixed contact is installed extends from the rear end of the rear bracket to the front thereof. .

[For production]

In the engine starter according to the present invention, the armature rotating shaft, the output rotating shaft, and the electromagnetic switch shaft are arranged in series on one axis, and the bearing of the output rotating shaft is held cantilevered by a sleeve bearing, and the rotating axis of the output rotating shaft is The armature rotating shaft is supported by a bearing fitted in the bearing recess at the front of the rear bracket, and the armature rotating shaft is supported by the bearing recess at the front of the rear bracket. The fixed contact is installed inside the rear bracket by utilizing the space of the recess provided from the end to the front, and the rear bracket portion is fully utilized for bearings and switches.

〔Example〕

An embodiment of the present invention will now be described with reference to the drawings.

In Fig. 1, the front refers to the right side of the corresponding component, and the rear refers to the left side, and 1 is the armature of the DC motor,
It consists of the elements described below. 2 is an armature core, 3 is a tubular armature rotating shaft having an armature core 12 attached to its intermediate part and a pipe hole 3a, and the extension surface intersects the axis at a predetermined angle, for example, a planar brush contact that is perpendicular to the armature core. Surface 4a
A face type commutator 4 having a
The armature coil 5 wound around the armature coil 5 is connected as appropriate.

6 is a brush and a retainer, and a spring 6 is placed on the rear side.
is urged forward by a, and the brush tip touches the brush contact surface 4.
It is pressed against a. Reference numeral 7 denotes a rear bracket for a DC motor made of plastic, which accommodates the brush and retainer 6 so as to be movable back and forth, and has a plurality of holder holes 7a provided in parallel with the central axis, and a plurality of holder holes 7a provided in parallel with this axis. A recessed portion 7b formed further forward from the rear end on the axis side of 7a.
and has. In addition, the rear bracket 7 has a shaft circumferential through hole 7C in the front-rear direction, which is the axial direction, in the center of the bottom surface of the recess 7b, and a bearing provided at the front end of the rear bracket 7, which is the front end of the shaft circumferential through hole 7C. It has a recessed portion 7d. moreover,
The rear bracket 7 is inserted into the holder hole 7 from the inner peripheral surface of the recess 7b.
The hole 7e of the recess 7b that communicates with
7g of through-holes for screws provided, for example, perpendicularly to the
has. A bearing 8 supports the rearmost end of the armature rotating shaft 3, and is fitted into the bearing recess 7d.

Reference numeral 9 denotes a yoke of a DC motor whose rear end surface abuts against the front end surface of the rear bracket 7, and a plurality of permanent magnets 9a that generate a field in the armature 1 are fixedly installed on the inner peripheral surface. As shown in the figure, a front bracket 10 having an internal gear 10a constituting a planetary gear device is attached to the stepped outer edge of the front end surface using its stepped rear edge.

This front bracket 10 has a hole diameter reduced by a plurality of stepped recesses formed inside from the rear to the front, and an internal gear 10a formed on the inner peripheral surface of the rear.
It has a bearing recess 10b formed in the inner middle part, a small diameter hole 10c in the front part, and a screw hole 10d formed forward from the rear end surface.

11 is a spur gear as a sun gear formed around the front end of the armature rotating shaft 3; 12 is a planetary gear;
and the internal m gear 10a meshes with both of them.

13 is a bearing fitted to the inner peripheral surface of the planetary gear 12, 14 is a support bin that supports the bearing 13, and 15 is an overrunning clutch having a conventional overrunning clutch mechanism, which is located on the inner periphery near the axis. It is possible to engage or disengage from an overrunning clutch inner 15A having helical spline teeth 15a provided on the surface and an inner protrusion 15b which makes the hole diameter smaller than this inner diameter at the front thereof, and a support pin 14 at the rear thereof. The overrunning clutch outer 15B is fixed to the overrunning clutch outer 15B, the overrunning clutch inner 15A, and the overrunning clutch outer 15B.

A bearing 16 is fitted into the overrunning clutch inner 15A to support a radial load, and is fitted into the recess 10b of the front bracket 10.

Reference numeral 17 denotes an output rotating shaft having a recess 17a on the rear end surface, and a spline fitting tooth 18 having a diameter larger than the pipe inner diameter of the front end opening of the armature rotating shaft 3 is formed in the middle part. Slidably splined. Reference numeral 19 denotes the front side surface of the spline fitting tooth 18 which is closer to the axis of the output rotating shaft 17 than the root of the tooth, and the inner protrusion 15b.
The output rotating shaft 17 is always biased rearward by a spring interposed between the rear end face of the output rotating shaft 17 and the rear end surface of the output rotating shaft 17. 20 is a pinion fitted to a straight spline 21 formed at the front end of the output rotation shaft 17, 22 is a stopper provided at the front end of the output rotation shaft 17, and the recess at the rear of the pinion 2o and the output rotation shaft This is to lock the pinion 20, which is biased forward 2ζ by a spring interposed between the steps 17, to the output rotating shaft 17.

23 is fitted into the inner peripheral surface of the tube hole 3a of the armature rotating shaft 3,
A sleeve bearing 24 is located at the center of the front end of the yoke 9 and supports the rear part of the output rotation shaft 17 inserted from the front end opening of the tube hole 3a, and enables linear movement and rotational movement of the output rotation shaft 17 in the front-rear direction. The armature rotating shaft 3 is supported between the armature core 2 mounting portion and the spur gear 11 by a bearing fitted in a certain bearing hole.

25 is an electromagnetic switch directly connected to the rear of the DC motor having the armature 1, and has a switch mechanism for supplying power to the armature 1 during excitation and a mechanism for applying thrust to the output rotating shaft 17, as described below. It consists of the elements described in . 26! This case has an opening on the 71i'iJ end side, and the front end surface is in a state of abutting against the rear end surface of the rear bracket 7. Reference numeral 27 denotes a fin portion at the front of the case 26 that protrudes outward from the rear bracket 7 and has a bolt hole in the front-rear direction, and 28 is inserted into the hole of the fin portion 27 and screwed into the screw hole 10d, thereby connecting the case 26 to a DC motor. Fasten and rear bracket 7
This is the bolt that connects the 29 is a bobbin around which the excitation coil 30 is wound and housed in the case 26 with the winding hole facing in the front-rear direction. Reference numeral 31 denotes a plunger made of ferromagnetic material, which has a hollow part 31a at the rear and which is inserted into the case 26 to hold the bobbin 2.
The plunger pipe portion 31b is movably fitted loosely into the winding hole No. 9, and has a hole in the front-rear direction that connects to the hollow portion 31a at its front portion. 32 fits into the inner peripheral surface of the opening of the case 26 and fixes the bobbin 29 with a step, and a bearing hole 32 is provided in the center.
The core 33 having the shape a is a spring interposed between the rear end surface of the core 32 and the front step at the rear of the plunger 31, and urges the plunger 31 rearward. 34 is a bearing fitted into the bearing hole 32a of the core 32, and the plunger pipe portion 31b.
is supported on a shaft so that it can move forward and backward.

Reference numeral 35 denotes a plunger rod having a T-shaped longitudinal section, the rear end of which is disposed within the hollow portion 31a, and the rear end surface is pushed forward by a spring 36A disposed rearward within the hollow portion 31a. The front part from the rear end thereof has a rond shape, passes through the plunger pipe part 31b, passes through the shaft circumferential through hole 7c, and is further inserted into the armature rotation shaft 3 from the rear end opening, and is inserted into the armature rotation shaft 3 from the rear end. Bearing 36B fitted into end tube hole 3a
It is supported by a shaft. The front end surface of the plunger rod 35 is always in contact with the steel ball 37 that is in contact with the recess 17a.

Reference numeral 38 denotes an insulator mounted on the outer peripheral surface of the front end of the plunger tube 31b in the space between the recess 7b and the core 32, and has a step on the front edge.

Reference numeral 39 denotes a movable contact having a fitting hole, which is fitted into the stepped portion of the insulator 38.

Reference numeral 40 denotes an L-shaped fixed contact, which is disposed inside the recess 7b, with one side thereof facing the movable contact 39.

A screw 41 is connected to one side of the fixed contact 40 on the opposite side to the other side, and is projected to the outside of the rear bracket 7 through the screw through hole 7g, and a nut 42 is screwed into this projected portion. As a result, the external terminal is configured and the fixed contact 40 is fixed to the rear bracket 7.

Note that, except for the fixed contacts 40 that are connected to a DC power supply (not shown), the rest are connected to the e-side brush and holder 6 by lead wires (not shown), and the e-side brush and holder 6 are connected to the e-side brush and holder 6 by lead wires (not shown). connected by wires. Further, the Φ side terminal of the DC power source is externally connected to the unconnected fixed contact 40 by fastening a lead wire 42 (not shown). Further, the DC power supply is connected to the exciting coil 3 via a starter switch (not shown).
Connected to 0.

Next, the operation of one embodiment of the present invention will be explained.

When the starter switch is open,
Since the excitation coil 30 is in a de-energized state, it is not excited, and the force applied to the plunger 31 (only the force of the spring 33) is biased backward by the spring 33, so that the plunger 31 and the plunger rod 35 move within the movement range. It is positioned at the rear within the

Therefore, the output rotating shaft 17 does not receive thrust from the Ti magnetic switch 25, but is biased backward by the spring 19, so that the front end surface of the armature rotating shaft 3 and the rear surface of the spline fitting teeth 18 are aligned. It is positioned backward to the position shown in the figure. Further, at this time, the movable contact 39 is separated from the fixed contact 40, so that the fixed contact 40 is in a floating state, and power is not supplied to the armature 1 from the DC power supply, and the armature 1 is stopped.

By closing the starter switch, the excitation coil 30 is energized and excited, and the plunger 31 is urged forward and moved by the electromagnetic force caused by this excitation. Due to this movement, the movable contact 39 also moves forward, and the movable contact 39 comes into contact with the fixed contact 40.

Due to this contact, the fixed contacts 40 are short-circuited via the movable contact 39, and the current from the DC power source is transferred to the fixed contacts 40.
(from the brush electrically connected to the fixed contact 40 and the brush of the retainer 6), flows through the chair-shaped commutator 4, and further flows through the armature coil 5 to reach the ground side. The rotational force generated by such energization of the armature 1 is transmitted from the spur gear 11 to the planetary gear 12, and is transmitted to the overrunning clutch 15 as a revolving force of the planetary gear 12. Since the overrunning clutch 15 is engaged by the action of the roller 15c, the revolution force transmitted to the overrunning clutch 15 is transmitted from the spline-fitting helical spline teeth 15a to the spline-fitting teeth 18. As a result, the output rotating shaft 17 rotates together with the pinion 20 at a reduced speed relative to the rotation of the armature 1.

On the other hand, as the plunger 31 biased forward as described above pushes the plunger rod 35 forward via the spring 36A, the output rotating shaft 17 receives a forward thrust from the plunger rod 35 via the steel ball 37. This thrust causes the pinion 20 to move forward together with the pinion 20 against the force of the spring 19.

At this time, the spline fitting teeth 18 move forward while fitting into the helical spline teeth 15a to change their fitting position. The pinion 20, which is projected forward from the small diameter hole 10c by the forward movement of the output rotating shaft 17, meshes with a ring gear on the outer periphery of a flywheel attached to the engine.

Therefore, the rotational force of the armature 1 is transmitted to the ring gear in a decelerated form by the binion mechanism, thereby starting the engine.

Immediately after the engine starts, the rotational force of the engine is transmitted to the pinion 20 via the ring gear, so the pinion 20 speeds up its rotation together with the output rotating shaft 17, and the overrunning clutch 15 is activated by the action of the roller 15c caused by this rotation. The pinion 20 is separated from the output rotating shaft 17.
It idles with etc.

Further, when the starter switch is opened after starting the starter, the starter returns to the initial state (the state shown in the figure).

In the above embodiment, a face-type commutator is used as the commutator, but a conventional commutator may also be used.

Furthermore, in the above embodiment, a planetary gear reduction mechanism is provided between the armature rotation shaft and the output rotation shaft, but if there is no need to reduce the rotational speed of the output rotation shaft, a planetary gear reduction mechanism may be used. It's fine even if there isn't.

Further, in the above embodiment, a permanent magnet is used to generate the magnetic field of the electric motor, but the same effect can be obtained even if a coil is wound around the magnetic pole core.

Further, in the above embodiment, the fixed contact 40 and the e-side brush 6 are connected by a lead wire, but the lead wire may not be used and only direct contact may be made through the hole 7e.

〔Effect of the invention〕

As described above, according to the present invention, an electric motor generates a rotational force for starting an engine when energized, and when the engine is started, the rotational force of the electric motor is transmitted to the engine through a pinion provided at one end of an output rotating shaft. A thrust for moving the output rotation shaft forward in the direction of its rotation axis is applied to the output rotation shaft by the electromagnetic force generated when the pinion mechanism and the starter switch are turned on, and a switch having a moving contact and a fixed contact is turned on. Above B:h
Each shaft part of an electromagnetic switch for energizing the motor is arranged in series, the armature rotating shaft of the motor is tubular, and a sleeve bearing for supporting the rear part of the output rotating shaft is fitted on the inner peripheral surface of the pipe. The rear bracket of the electric motor is molded from plastic, and a bearing recess for fitting a bearing for supporting the rear part of the armature rotating shaft is provided in the front part of the rear bracket. Since it is constructed so that a recessed portion in which the fixed contact is disposed in the front portion is provided, the overall length can be shortened and the size can be reduced, and the weight can also be reduced, making it extremely easy to wear.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an engine starter according to an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional engine starter. In the figure, 1... armature, 3... armature rotation axis,
3a...Inside pipe, 4...Face type commutator, 6
...Brush and retainer, 7...Rear bracket, 7
m... Hole for holder, 7b... Recessed part, 7d... Recessed part for bearing, 7e... Hole in the recessed part, 7f... Recessed part in the recessed part, 7
g... Through hole for screw, 8... Bearing, 10... Front bracket, 10a... Internal gear, 11... Sun gear, 12... Planetary gear, 15... Over Running clutch, 15a...helical spline tooth, 1
7... Output rotating shaft, 18... Spline fitting teeth, 1
9... Spring, 20... Pinion, 23... Sleeve bearing, 25... Electromagnetic switch, 30... Excitation coil, 31... Plunger, 31a... Hollow part, 31b... Plunger pipe section, 33... Spring, 35
...Plunger rod, 36A...Spring, 38...Insulator, 39...Movable contact, 40...Fixed contact, 42
...Naruto.

Claims (3)

[Claims] (1) An electric motor that has a tubular armature rotation shaft and generates rotational force for starting the engine when energized, and is provided so as to be movable forward along the axis of rotation in response to thrust when the engine is started. It also has an output rotating shaft at its front end with a pinion that meshes with the starting ring gear on the engine side, a pinion mechanism that transmits the rotational force transmitted from the electric motor to the ring gear at the time of starting, and a starter switch that turns on the starter switch. is energized, and the electromagnetic force generated by the energization urges the movable body forward to provide the above-mentioned thrust, and turns on a switch whose contact portion includes a fixed contact and a movable contact attached to the intermediate portion of the movable body. and an electromagnetic switch for energizing the electric motor, the engine starter having a rear part of the output rotating shaft and a rod-shaped front part of the movable body inserted into a pipe of the armature rotating shaft from opposite directions. A sleeve bearing for supporting the rear part of the output rotating shaft is fitted onto the inner circumferential surface of the tube of the armature rotating shaft, a rear bracket of the motor is molded with plastic, and the armature rotating shaft is attached to the front part of the rear bracket. A starter for an engine, characterized in that a bearing recess into which a bearing for supporting a rear end is fitted is provided, and a recess into which the fixed contact is disposed extends from the rear end to the front of the rear bracket. (2) The commutator fitted to the rear part of the armature rotating shaft is a face-type commutator having a flat contact surface that contacts the brush tip of the brush and the retainer, and the bearing recess of the rear bracket and the rear bracket 2. The engine starter according to claim 1, further comprising a holder hole in which the brush and retainer are movably housed in a portion of the rear bracket around the recess. (3) The moving body is made of a ferromagnetic material, the rear part is hollow, the front part is connected to the hollow, and the plunger has a hole in the direction of movement, which is the direction of the central axis, and the rear end is arranged in the hollow. A plunger rod is biased forward by a spring disposed at the rear and has a rod shape from the rear end to the front, and the movable contact is connected to the fixed contact via an insulator on the outer periphery of the front part of the plunger. Claim 1, characterized in that it is attached so as to face the contact surface of the
The engine starter according to item 1 or 2.