CN105781846B

CN105781846B - Compact internal combustion engine starter with external electromagnetic switch

Info

Publication number: CN105781846B
Application number: CN201610364484.7A
Authority: CN
Inventors: 郑有存; 孟青; 吴伟; 郑淑荣; 孟现鑫
Original assignee: Shuozhou Santong Yida Automobile Electric Appliance Co ltd
Current assignee: Shuozhou Santong Yida Automobile Electric Appliance Co ltd
Priority date: 2016-05-26
Filing date: 2016-05-26
Publication date: 2020-06-09
Anticipated expiration: 2036-05-26
Also published as: CN105781846A

Abstract

The invention provides an internal combustion engine starter with a compact external electromagnetic switch, belongs to the technical field of internal combustion engine starters, and mainly solves the problems that the fault rate is high and the length of the whole engine is not easy to shorten in the prior art. Including drive shaft, shift fork, shell, external electromagnetic switch, motor shaft, its characteristics are: the device also comprises a one-way speed reducer and a buffer device; the one-way speed reducer comprises a speed reducer and a one-way device, wherein the speed reducer is a planetary gear reducer and comprises a first planetary reducer inner gear ring or a second planetary reducer inner gear ring and a speed reduction driving shaft; the one-way device comprises a first one-way speed reducer shell and a friction braking device; the first one-way speed reducer shell is barrel-shaped, the inner wall of the first one-way speed reducer shell is provided with a first spring roller groove, and the outer wall of the first one-way speed reducer shell is provided with a first outer clamping table; a casing of the one-way speed reduction device is sleeved on an inner gear ring of the planetary reducer. The buffer device is composed of a buffer block, an inner clamping table and an outer clamping table.

Description

Compact internal combustion engine starter with external electromagnetic switch

Technical Field

The invention belongs to the technical field of internal combustion engine starters, and particularly relates to an internal combustion engine starter with a compact external electromagnetic switch.

Background

At present, most internal combustion engine starters are speed reduction starters. No matter the starter of the eccentric speed reducing structure or the planetary speed reducing structure, the speed reducing structure and the isolator are sequentially and axially connected and installed on the same starter. The roller type isolator commonly used at present has high failure rate, and the length of the whole machine is not easy to shorten, thereby being the bottleneck of the technical development of the same power, miniaturization and light weight in the starter industry.

Disclosure of Invention

The invention aims to solve the problems of long length, rigid contact, overweight load of a shifting fork of an electromagnetic switch and high failure rate of a one-way device of the starter in the prior art, and provides an internal combustion engine starter with a compact external electromagnetic switch and a buffer device.

The technical scheme adopted by the invention for solving the technical problems is as follows:

the utility model provides a compact external electromagnetic switch's internal-combustion engine starter, includes drive shaft, shift fork, shell, external electromagnetic switch, motor pivot, its characteristics are: the device also comprises a one-way speed reducer and a buffer device; the one-way speed reducer comprises a speed reducer and a one-way device, wherein the speed reducer is a planetary gear reducer and comprises a first planetary reducer inner gear ring and a speed reduction driving shaft; the one-way device comprises a first one-way speed reducer shell and a friction braking device; the first one-way speed reducer shell is barrel-shaped, the inner wall of the first one-way speed reducer shell is provided with a first spring roller groove, and the outer wall of the first one-way speed reducer shell is provided with a first outer clamping table; the shell of the first one-way speed reducing device is sleeved on an inner gear ring of the first planetary speed reducer; the friction braking device comprises a spring and a roller which are positioned in a first spring roller groove; one end of the spring abuts against the side wall of the first spring roller groove, and the other end of the spring abuts against the roller through the spring seat or directly; the bottom of the first spring roller groove is made into a slope shape, and a gradual change gap is formed between the bottom of the first spring roller groove and the outer wall of the inner gear ring of the first planetary reducer;

the buffering device comprises a first inner clamping table positioned at the end part of the inner wall of a first shell, a first buffering block and a first outer clamping table positioned on the outer wall of a first unidirectional speed reducer shell, the first unidirectional speed reducer shell is positioned in the first shell, and a first hole on the first buffering block is sleeved on the first outer clamping table and positioned between the two first inner clamping tables;

the speed reduction driving shaft is provided with a spiral spline; the drive shaft is connected with the speed reduction drive shaft through a helical spline.

When the spring is a flat spring, the spring seat is a flat spring seat;

when the springs are two round springs, the spring seats are round spring seats;

the flat spring seat is provided with a flat spring clamping table for placing the flat spring, and the surface contacted with the roller is made into an arc surface matched with the roller; the circular spring seat is provided with a circular spring clamping table for placing a circular spring, and the surface in contact with the roller is also made into an arc surface matched with the roller.

The one-way device can also arrange the spring roller groove on the outer wall of the inner gear ring of the planetary reducer, namely, the outer wall of the inner gear ring of the second planetary reducer is provided with a second spring roller groove;

the one-way device can also adopt a roller positioning device and a torsion spring structure, and specifically comprises a shell of a No. five one-way speed reducing device, an inner gear ring of a planetary speed reducer and a roller; the shell of the No. five one-way reduction gear is sleeved outside the inner gear ring of the planetary reducer; the one-way device also comprises a roller positioning device and a torsion spring; the roller is positioned in a roller groove on the roller positioning device and is placed in a gap between the inner wall of the shell of the No. five one-way speed reduction device and the outer wall of the inner gear ring of the planetary speed reducer along with the roller positioning device, wherein: a plurality of spaces for containing the rollers are evenly distributed on the inner wall of the shell of the fifth one-way speed reducer, and a gradual change gap which is enough for clamping the rollers is formed between the bottom of the space and the outer wall of the inner gear ring of the planetary reducer; one end of the torsion spring is fixed on the roller positioning device, the other end of the torsion spring is fixed on the shell of the No. five one-way reduction gear, and the torsion spring is installed in place and then keeps an opening trend, so that all the rollers are in a clamped position.

The roller positioning device is made of metal or plastic.

Buffer blocks in the buffer device can also be arranged on the outer wall of the bottom of the shell of the unidirectional speed reducer, namely, an outer clamping table is arranged on the outer wall of the bottom of the second shell, and the second buffer block is sleeved on the outer clamping table and arranged between inner clamping tables on the inner wall of the middle part of the second shell to form the buffer device.

Compared with the prior art, the invention has the following beneficial effects:

because the planetary reduction gear and the one-way device are overlapped and combined into the integral one-way planetary reducer of the starter, the structure of the starter is compact, the length is shortened, the stress structure of the one-way clutch is changed, the failure rate is reduced, and the bottleneck of the development of the starter industry with the same power, miniaturization, light weight, high performance and long service life is solved. The buffer device is adopted to avoid rigid contact between the one-way speed reducer and the shell of the starter, and the service life of the whole machine is prolonged.

Drawings

FIG. 1 is a schematic structural view of a buffer block located on a side wall of a casing of a one-way reduction gear according to the present invention;

FIG. 2 is a schematic structural view of a one-way reduction gear with a buffer block on the side wall of the casing of the one-way reduction gear of the invention;

FIG. 3 is a side view of the structure of FIG. 2 in cooperation with a drive shaft;

FIG. 4 is a schematic view of a buffer block located on a side wall of a casing of the one-way reduction gear of the present invention;

FIG. 5 is a schematic view of the flat spring structure of the present invention;

FIG. 6 is a top view of the structure shown in FIG. 5;

FIG. 7 is a schematic view of the flat spring seat structure of the present invention;

FIG. 8 is a schematic view of the structure of the round spring of the present invention;

FIG. 9 is a top view of the structure shown in FIG. 8;

FIG. 10 is a schematic view of a circular spring seat;

FIG. 11 is a schematic structural view of a buffer block of the present invention located at the bottom of the casing of the single reduction gear;

FIG. 12 is a schematic structural view of a single-direction reduction gear with a buffer block at the bottom of the casing of the single-direction reduction gear of the present invention;

FIG. 13 is a side view of FIG. 12;

FIG. 14 is a sectional view taken along line A-A of FIG. 11;

FIG. 15 is a schematic view of the structure of the buffer block at the bottom of the casing of the single-direction reduction gear of the present invention;

FIG. 16 is a schematic structural view of the one-way reduction gear of the present invention, in which the buffer blocks are located on the side wall of the housing of the one-way reduction gear and the outer wall of the inner gear ring of the planetary reducer is provided with spring roller slots;

FIG. 17 is a schematic structural view of the one-way reduction gear of the present invention, in which the buffer block is located at the bottom of the one-way reduction gear housing and the outer wall of the inner gear ring of the planetary reducer is provided with a spring roller groove;

fig. 18 is a schematic view of the roller positioning device of the present invention.

In the figure: 1-a drive shaft; 2, a shifting fork; 2-1-a fork groove; 3, a shell of the clamping table is arranged at the outer end of the inner wall; 3 a-a shell with a clamping table is arranged in the middle of the inner wall; 4-one-way reduction gear; 4-1-a planetary reducer ring gear; 4a-1, an inner gear ring of the planetary reducer with a spring roller groove on the outer wall; 4-2-spring; 4-2-1-flat spring; 4-2-flat spring seat; 4-2-3-round spring; 4-2-4-round spring seat; 4-2-5-flat spring clamping table; 4-2-6-arc surface; 4-2-7-round spring clamping table; 4-3-rollers; 4-buffer block one; 4 a-4-buffer block II; 4-5-a shell of the one-way speed reduction device; 4 a-5-No. two unidirectional reduction gear shells; 4 b-5-No. three unidirectional reduction gear shell; 4 c-5-four unidirectional reduction gear shell; 4 d-5-five unidirectional reduction gear shell; 4-6-a spring roller groove; 4 a-6-spring roller groove arranged on the outer wall of the inner gear ring of the planetary reducer; 4-7-one outer clamping table; 4a-7, a clamping table arranged on the outer wall of the bottom of the shell of the one-way speed reducer; 4-8-card table of the first number; 4 a-8-second card table; 4-9-deceleration drive shaft; 4-10-side wall buffer block holes; 4 a-10-bottom buffer block holes; 4-11-helical splines; 5, an external electromagnetic switch; 6-motor shaft; 7-roller positioning device; 8-torsion spring.

Detailed Description

Embodiment one (the buffer block is arranged on the outer wall of the side part of the one-way reduction gear barrel-shaped shell, and the first spring roller groove is arranged on the inner wall of the side part of the one-way reduction gear barrel-shaped shell)

As shown in fig. 1, the compact internal combustion engine starter with the external electromagnetic switch comprises a driving shaft 1, a shifting fork 2, a first shell 3, the external electromagnetic switch 5 and a motor rotating shaft 6, and is characterized in that: the device also comprises a one-way speed reducing device 4 and a buffer device; the one-way reduction gear 4 comprises a reduction gear and a one-way device, as shown in fig. 2, the reduction gear is a planetary gear reducer and comprises a first planetary reducer ring gear 4-1 and a reduction driving shaft 4-9; the one-way device comprises a first one-way speed reducer shell 4-5 and a friction braking device; the first one-way speed reducer shell 4-5 is barrel-shaped, the inner wall of the first one-way speed reducer shell is provided with a first spring roller groove 4-6, and the outer wall of the first one-way speed reducer shell is provided with a first outer clamping table 4-7; the first one-way speed reducer shell 4-5 is sleeved on the first planetary speed reducer inner gear ring 4-1; the friction braking device comprises a spring 4-2 and a roller 4-3 which are positioned in a first spring roller groove 4-6; one end of the spring 4-2 is abutted against the side wall of the first spring roller groove 4-6, and the other end of the spring is abutted against the roller 4-3 through a spring seat or directly; the bottom of the first spring roller groove 4-6 is made into a slope shape, and a gradual change gap is formed between the bottom of the first spring roller groove and the outer wall of the inner gear ring 4-1 of the first planetary reducer;

the buffering device comprises a first inner clamping table 4-8 positioned at the end part of the inner wall of a first shell 3, a first buffering block 4-4 and a first outer clamping table 4-7 positioned on the outer wall of a first unidirectional reduction gear shell 4-5, the first unidirectional reduction gear shell 4-5 is positioned in the first shell 3, as shown in figure 4, a first hole 4-10 on the first buffering block 4-4 is sleeved on the first outer clamping table 4-7 and positioned between the two first inner clamping tables 4-8;

as shown in fig. 3, the reduction drive shaft 4-9 is provided with helical splines 4-11; the drive shaft 1 is connected with a reduction drive shaft 4-9 by helical splines 4-11.

As shown in fig. 5 and 6, when the spring 4-2 is a flat spring 4-2-1, the spring seat is a flat spring seat 4-2-2;

as shown in fig. 8 and 9, when the spring 4-2 is two round springs 4-2-3, the spring seat is a round spring seat 4-2-4;

as shown in fig. 7, the flat spring seat 4-2-2 is provided with a flat spring clamping table 4-2-5 for placing the flat spring 4-2-1, and the surface contacted with the roller is made into an arc surface 4-2-6 matched with the roller 4-3; as shown in figure 10, the round spring seat 4-2-4 is provided with a round spring clamping table 4-2-7 for placing the round spring 4-2-3, and the surface contacted with the roller 4-3 is also made into a circular arc surface 4-2-6 matched with the roller 4-3.

As shown in fig. 18, the one-way device comprises a five-way reduction gear housing 4d-5, a planetary reducer ring gear 4-1 and a roller 4-3; the shell 4d-5 of the fifth one-way reduction gear is sleeved outside the inner gear ring 4-1 of the planetary reducer; the one-way device also comprises a roller positioning device 7 and a torsion spring 8; the rollers 4-3 are positioned in roller grooves on the roller positioning device 7 and are placed in a gap between the inner wall of the shell 4d-5 of the No. five one-way speed reducing device and the outer wall of the inner gear ring 4-1 of the planetary speed reducer along with the roller positioning device 7, wherein: a plurality of spaces for containing the rollers 4-3 are evenly distributed on the inner wall of the shell 4d-5 of the fifth one-way speed reducer, and a gradual change gap which is enough for clamping the rollers 4-3 is formed between the bottom of the space and the outer wall of the inner gear ring 4-1 of the planetary reducer; one end of the torsion spring 8 is fixed on the roller positioning device 7, the other end of the torsion spring 8 is fixed on a shell 4d-5 of the No. five one-way reduction gear, and the torsion spring 8 is required to keep an opening trend after being installed in place, so that all the rollers 4-3 are positioned at a clamping position.

The roller positioning device 7 is made of metal or plastic.

EXAMPLE two (the buffer block is disposed on the outer wall of the bottom of the isolator tub case and the friction brake is disposed on the inner tub wall of the isolator tub case)

As shown in fig. 11, the compact internal combustion engine starter with the external electromagnetic switch comprises a driving shaft 1, a shifting fork 2, a second shell 3a and the external electromagnetic switch 5, and is characterized in that: the device also comprises a one-way speed reducing device 4 and a buffer device; the one-way reduction gear 4 comprises a reduction gear and a one-way gear, as shown in fig. 12, the reduction gear is a planetary gear reducer and comprises a first planetary reducer ring gear 4-1 and a reduction driving shaft 4-9; the one-way device comprises a third one-way speed reducer shell 4b-5 and a friction braking device; the third unidirectional reduction gear shell 4b-5 is barrel-shaped, the inner wall of the third unidirectional reduction gear shell is provided with a first spring roller groove 4-6, the outer wall of the third unidirectional reduction gear shell is not provided with a clamping table, and the outer wall of the bottom of the third unidirectional reduction gear shell is provided with a second outer clamping table 4 a-7; the shell 4b-5 of the third one-way reduction gear is sleeved on the inner gear ring 4-1 of the first planetary reducer; the one-way device comprises a spring 4-2 and a roller 4-3 which are positioned in a first spring roller groove 4-6; one end of the spring 4-2 is abutted against the side wall of the first spring roller groove 4-6, and the other end of the spring is abutted against the roller 4-3 through a spring seat or directly; the bottom of the first spring roller groove 4-6 is made into a slope shape, and a gradual change gap is formed between the bottom of the first spring roller groove and the outer wall of the inner gear ring 4-1 of the first planetary reducer;

as shown in fig. 14, the buffering device comprises a second inner clamping table 4a-8, a second buffering block 4a-4 and a second outer clamping table 4a-7, wherein the second inner clamping table and the second buffering block are positioned on the inner wall of the middle part of a second shell 3a, the second outer clamping table is positioned on the outer wall of the bottom of a third unidirectional reduction gear shell 4b-5, the third unidirectional reduction gear shell 4b-5 is positioned in the second shell 3a, and as shown in fig. 15, second holes 4a-10 on the second buffering block 4a-4 are sleeved on the second outer clamping table 4a-7 and positioned between the two second inner clamping tables 4 a-8;

embodiment three (buffer block is arranged on the outer wall of the side part of the barrel-shaped shell of the one-way speed reducer, and the spring roller is positioned on the outer wall of the inner gear ring of the speed reducer)

As shown in fig. 1 and 16, the compact internal combustion engine starter with the external electromagnetic switch comprises a driving shaft 1, a shifting fork 2, a first shell 3 and the external electromagnetic switch 5, and is characterized in that: the device also comprises a one-way speed reducing device 4 and a buffer device; the one-way reduction gear 4 comprises a reduction gear and a one-way gear, as shown in fig. 16, the reduction gear is a planetary gear reducer and comprises a second planetary reducer ring gear 4a-1 and a reduction driving shaft 4-9; the one-way device comprises a second one-way speed reducer shell 4a-5 and a friction braking device; the second one-way reduction gear shell 4a-5 is barrel-shaped, the inner wall of the second one-way reduction gear shell is arc-shaped, and the outer wall of the second one-way reduction gear shell is provided with a first outer clamping table 4-7; the shell 4a-5 of the second one-way reduction gear is sleeved on an inner gear ring 4a-1 of the second planetary reducer; a second spring roller groove 4a-6 is formed in the outer wall of the inner gear ring 4a-1 of the second planetary reducer, and the friction braking device comprises a spring 4-2 and a roller 4-3 which are positioned in the second spring roller groove 4 a-6; one end of the spring 4-2 is propped against the side wall of the second spring roller groove 4a-6, and the other end of the spring 4-2 is propped against the roller 4-3 through a spring seat or directly; the bottom of the second spring roller groove 4a-6 is made into a slope shape, and a gradual change gap is formed between the bottom of the second spring roller groove and the inner wall of the second one-way speed reducing device shell 4 a-5;

as shown in fig. 16, the buffering device comprises a first inner clamping table 4-8, a first buffering block 4-4 and a first outer clamping table 4-7, wherein the first inner clamping table is positioned at the end part of the inner wall of a first shell 3, the first outer clamping table is positioned on the outer wall of the side part of a second unidirectional reduction gear shell 4a-5, the second unidirectional reduction gear shell 4a-5 is positioned in the first shell 3, and as shown in fig. 4, a first hole 4-10 in the first buffering block 4-4 is sleeved on the first outer clamping table 4-7 and is positioned between two first inner clamping tables 4-8;

embodiment four (buffer block is arranged on the outer wall of the bottom of the barrel-shaped shell of the one-way reduction gear, and the spring roller is positioned on the outer wall of the inner gear ring of the reducer)

As shown in fig. 11 and 17, the compact internal combustion engine starter with the external electromagnetic switch comprises a driving shaft 1, a shifting fork 2, a second shell 3a and the external electromagnetic switch 5, and is characterized in that: the device also comprises a one-way speed reducing device 4 and a buffer device; the one-way reduction gear 4 comprises a reduction gear and a one-way gear, as shown in fig. 17, the reduction gear is a planetary gear reducer and comprises a second planetary reducer ring gear 4a-1 and a reduction driving shaft 4-9; the one-way device comprises a No. four one-way speed reducer shell 4c-5 and a friction braking device; the shell 4c-5 of the fourth unidirectional reduction gear is barrel-shaped, the inner wall of the shell is arc-shaped, the outer wall of the shell is not provided with a clamping table, and as shown in fig. 14, the outer wall of the bottom of the shell is provided with a second outer clamping table 4 a-7; the shell 4c-5 of the fourth one-way reduction gear is sleeved on an inner gear ring 4a-1 of a second planetary reducer, and a second spring roller groove 4a-6 is formed in the outer wall of the inner gear ring 4a-1 of the second planetary reducer; the friction braking device comprises a spring 4-2 and a roller 4-3 which are positioned in a second spring roller groove 4 a-6; one end of the spring 4-2 is propped against the side wall of the second spring roller groove 4a-6, and the other end of the spring 4-2 is propped against the roller 4-3 through a spring seat or directly; the bottom of the second spring roller groove 4a-6 is made into a slope shape, and a gradual change gap is formed between the bottom of the second spring roller groove and the inner wall of the fourth unidirectional speed reducing device shell 4 c-5;

as shown in fig. 14, the buffering device includes a second inner clamping table 4a-8, a second buffering block 4a-4 and a second outer clamping table 4a-7, the second inner clamping table and the second buffering block are located on the inner wall of the middle portion of a second shell 3a, the second outer clamping table is located on the outer wall of the bottom of a fourth unidirectional reduction gear shell 4c-5, the fourth unidirectional reduction gear shell 4c-5 is located in the second shell 3a, and as shown in fig. 15, second holes 4a-10 in the second buffering block 4a-4 are sleeved on the second outer clamping table 4a-7 and located between the two second inner clamping tables 4 a-8.

The working principle of the embodiment one is as follows:

when the engine is in work, the external electromagnetic switch 5 is electrified to drive the shifting fork 2, the shifting fork 2 shifts the driving shaft 1, so that the driving gear moves forwards (the speed reduction driving shaft 4-9 is connected with the driving shaft 1 through the helical spline 4-11) and is meshed with a flywheel gear ring of the engine, and the torque of the motor rotating shaft 6 is transmitted to the driving shaft 1 through the one-way planetary reducer and drives the engine to start. After the engine is started, the external electromagnetic switch 5 is powered off, the magnetic force disappears, and the shifting fork 2 shifts the driving shaft 1 and the driving gear to be separated from the flywheel gear ring of the engine under the action of the return spring of the magnetic switch, so that one-time starting period is completed.

When the planetary gear of the one-way planetary reducer drives the inner gear ring 4-1 of the planetary reducer to rotate clockwise, the shell 4-5 of the one-way speed reducer is not moved, the roller 4-3 is extruded into the narrow gap (the position smaller than the diameter of the roller) of the roller groove 4-6 of the first spring under the assistance of the spring 4-2 and the friction force, the inner gear ring 4-1 of the first planetary reducer is clamped and braked by the roller 4-3, the torque of the motor rotating shaft 6 passes through the planetary gear and the speed reduction driving shaft 4-9, and the driving shaft 1 and the driving gear are transmitted to the flywheel gear ring of the engine to start the engine.

When the engine is started and the rotating speed is higher than that of a starter, the driving gear is dragged down in the reverse direction of an engine flywheel, the inner gear ring 4-1 of the first planetary reducer is driven to rotate anticlockwise through the speed reduction driving shaft 4-9 and the planetary gear, the shell 4-5 of the one-way speed reduction device is not moved, the roller 4-3 extrudes the spring 4-2 under the action of friction force and rolls to the wide gap position (the position is larger than the diameter of the roller) of the roller groove 4-6 of the first spring, and at the moment, the brake of the inner gear ring 4-1 of the first planetary reducer is released, the inner gear ring rotates along with the planetary gear, the inner gear.

When power is output, the first planetary reduction inner gear ring 4-1 and the first one-way reduction device shell 4-5 are subjected to friction force and do not move relatively, so that the rotation trend of the one-way reduction device shell 4-5 is inevitably caused, and the first buffer block 4-4 enables the one-way reduction device shell 4-5 and the first shell 3 to avoid rigid collision, so that the service life of the starter is prolonged.

The working principles of the second to fourth embodiments are similar to those of the first embodiment, and are not described again.

Claims

1. The utility model provides an external electromagnetic switch's of compactness internal-combustion engine starter, includes drive shaft (1), shift fork (2), shell (3), external electromagnetic switch (5), motor shaft (6), characterized by: the device also comprises a one-way speed reducing device (4) and a buffer device; the one-way speed reducer (4) comprises a speed reducer and a one-way device, wherein the speed reducer is a planetary gear reducer and comprises a first planetary reducer inner gear ring (4-1) and a speed reduction driving shaft (4-9); the one-way device comprises a first one-way speed reducer shell (4-5) and a friction braking device; the first one-way speed reducer shell (4-5) is barrel-shaped, the inner wall of the first one-way speed reducer shell is provided with a first spring roller groove (4-6), and the outer wall of the first one-way speed reducer shell is provided with a first outer clamping table (4-7); the first one-way speed reducer shell (4-5) is sleeved on the first planetary reducer inner gear ring (4-1); the friction braking device comprises a spring (4-2) and a roller (4-3) which are positioned in a first spring roller groove (4-6); one end of the spring (4-2) is propped against the side wall of the first spring roller groove (4-6), and the other end of the spring (4-2) is propped against the roller (4-3) through a spring seat or directly; the bottom of the first spring roller groove (4-6) is made into a slope shape, and a gradual change gap is formed between the bottom of the first spring roller groove and the outer wall of the inner gear ring (4-1) of the first planetary reducer;

the buffer device comprises a first inner clamping table (4-8) positioned at the end part of the inner wall of a first shell (3), a first buffer block (4-4) and a first outer clamping table (4-7) positioned on the outer wall of a first unidirectional speed reducer shell (4-5), the first unidirectional speed reducer shell (4-5) is positioned in the first shell (3), and a first hole (4-10) in the first buffer block (4-4) is sleeved on the first outer clamping table (4-7) and positioned between two first inner clamping tables (4-8);

the speed reduction driving shaft (4-9) is provided with a spiral spline (4-11); the driving shaft (1) is connected with a speed reduction driving shaft (4-9) through a spiral spline (4-11);

when the spring (4-2) is a flat spring (4-2-1), the spring seat is a flat spring seat (4-2-2);

when the spring (4-2) is two round springs (4-2-3), the spring seat is a round spring seat (4-2-4);

the flat spring seat (4-2-2) is provided with a flat spring clamping table (4-2-5) for placing the flat spring (4-2-1), and the surface contacted with the roller is made into an arc surface (4-2-6) matched with the roller (4-3); the round spring seat (4-2-4) is provided with a round spring clamping table (4-2-7) for placing the round spring (4-2-3), and the surface contacted with the roller (4-3) is also made into an arc surface (4-2-6) matched with the roller (4-3).

2. The internal combustion engine starter with the compact external electromagnetic switch according to claim 1, characterized in that: the one-way device comprises a shell (4d-5) of a No. five one-way speed reducer, an inner gear ring (4-1) of a planetary speed reducer and a roller (4-3); the shell (4d-5) of the fifth one-way speed reducer is sleeved outside the inner gear ring (4-1) of the planetary speed reducer; the one-way device also comprises a roller positioning device (7) and a torsion spring (8); the rollers (4-3) are positioned in roller grooves on the roller positioning device (7) and are placed in a gap between the inner wall of a shell (4d-5) of the fifth unidirectional reduction gear and the outer wall of an inner gear ring (4-1) of the planetary reducer along with the roller positioning device (7), wherein: a plurality of spaces for containing the rollers (4-3) are evenly distributed on the inner wall of the shell (4d-5) of the fifth one-way speed reducer, and a gradual change gap which is enough for clamping the rollers (4-3) is formed between the bottom of the space and the outer wall of the inner gear ring (4-1) of the planetary reducer; one end of the torsion spring (8) is fixed on the roller positioning device (7), the other end of the torsion spring is fixed on a shell (4d-5) of the No. five one-way reduction gear, and the torsion spring (8) is installed in place and keeps an opening trend, so that all the rollers (4-3) are located at a clamping position.

3. The internal combustion engine starter with the compact external electromagnetic switch according to claim 2, characterized in that: the roller positioning device (7) is made of metal materials or plastic materials.

4. The utility model provides an internal-combustion engine starter of external electromagnetic switch of compactness, includes drive shaft (1), shift fork (2), No. two shells (3a) and external electromagnetic switch (5), characterized by: the device also comprises a one-way speed reducing device (4) and a buffer device; the one-way speed reducer (4) comprises a speed reducer and a one-way device, wherein the speed reducer is a planetary gear reducer and comprises a first planetary reducer inner gear ring (4-1) and a speed reduction driving shaft (4-9); the one-way device comprises a third one-way speed reducer shell (4b-5) and a friction braking device; the third unidirectional reduction gear shell (4b-5) is barrel-shaped, the inner wall of the third unidirectional reduction gear shell is provided with a first spring roller groove (4-6), the outer wall of the third unidirectional reduction gear shell is not provided with a clamping table, and the outer wall of the bottom of the third unidirectional reduction gear shell is provided with a second outer clamping table (4 a-7); the third unidirectional speed reducer shell (4b-5) is sleeved on the inner gear ring (4-1) of the first planetary speed reducer; the one-way device comprises a spring (4-2) and a roller (4-3) which are positioned in a first spring roller groove (4-6); one end of the spring (4-2) is propped against the side wall of the first spring roller groove (4-6), and the other end of the spring (4-2) is propped against the roller (4-3) through a spring seat or directly; the bottom of the first spring roller groove (4-6) is made into a slope shape, and a gradual change gap is formed between the bottom of the first spring roller groove and the outer wall of the inner gear ring (4-1) of the first planetary reducer;

the buffer device comprises a second inner clamping table (4a-8) and a second buffer block (4a-4) which are positioned on the inner wall of the middle part of a second shell (3a) and a second outer clamping table (4a-7) which is positioned on the outer wall of the bottom of a third unidirectional speed reducer shell (4b-5), the third unidirectional speed reducer shell (4b-5) is positioned in the second shell (3a), and a second hole (4a-10) in the second buffer block (4a-4) is sleeved on the second outer clamping table (4a-7) and positioned between the two second inner clamping tables (4 a-8).

5. The utility model provides an external electromagnetic switch's of compact internal-combustion engine starter, includes drive shaft (1), shift fork (2), shell (3) and external electromagnetic switch (5), characterized by: the device also comprises a one-way speed reducing device (4) and a buffer device; the one-way reduction gear (4) comprises a reduction gear and a one-way device, wherein the reduction gear is a planetary gear reducer and comprises a second planetary reducer inner gear ring (4a-1) and a reduction driving shaft (4-9); the one-way device comprises a second one-way speed reducer shell (4a-5) and a friction braking device; the second one-way reduction gear shell (4a-5) is barrel-shaped, the inner wall of the second one-way reduction gear shell is arc-shaped, and the outer wall of the second one-way reduction gear shell is provided with a first outer clamping table (4-7); the shell (4a-5) of the second one-way speed reducer is sleeved on an inner gear ring (4a-1) of the second planetary speed reducer; a second spring roller groove (4a-6) is formed in the outer wall of the second planetary reducer inner gear ring (4a-1), and the friction braking device comprises a spring (4-2) and a roller (4-3) which are located in the second spring roller groove (4 a-6); one end of the spring (4-2) is propped against the side wall of the second spring roller groove (4a-6), and the other end of the spring (4-2) is propped against the roller (4-3) through a spring seat or directly; the bottom of the second spring roller groove (4a-6) is made into a slope shape, and a gradual change gap is formed between the bottom of the second spring roller groove and the inner wall of the second one-way speed reducing device shell (4 a-5);

the buffer device comprises a first inner clamping table (4-8) positioned at the end part of the inner wall of a first shell (3), a first buffer block (4-4) and a first outer clamping table (4-7) positioned on the outer wall of the side part of a second unidirectional speed reducer shell (4a-5), wherein the second unidirectional speed reducer shell (4a-5) is positioned in the first shell (3), and a hole (4-10) in the first buffer block (4-4) is sleeved on the first outer clamping table (4-7) and positioned between the two first inner clamping tables (4-8).

6. The utility model provides an internal-combustion engine starter of external electromagnetic switch of compactness, includes drive shaft (1), shift fork (2), No. two shells (3a) and external electromagnetic switch (5), characterized by: the device also comprises a one-way speed reducing device (4) and a buffer device; the one-way reduction gear (4) comprises a reduction gear and a one-way device, wherein the reduction gear is a planetary gear reducer and comprises a second planetary reducer inner gear ring (4a-1) and a reduction driving shaft (4-9); the one-way device comprises a No. four one-way speed reducer shell (4c-5) and a friction braking device; the shell (4c-5) of the fourth unidirectional reduction gear is barrel-shaped, the inner wall of the shell is arc-shaped, the outer wall of the shell is not provided with a clamping table, and the outer wall of the bottom of the shell is provided with a second outer clamping table (4 a-7); the shell (4c-5) of the fourth one-way speed reducer is sleeved on an inner gear ring (4a-1) of a second planetary speed reducer, and a second spring roller groove (4a-6) is formed in the outer wall of the inner gear ring (4a-1) of the second planetary speed reducer; the friction braking device comprises a spring (4-2) and a roller (4-3) which are positioned in a second spring roller groove (4 a-6); one end of the spring (4-2) is propped against the side wall of the second spring roller groove (4a-6), and the other end of the spring (4-2) is propped against the roller (4-3) through a spring seat or directly; the bottom of the second spring roller groove (4a-6) is made into a slope shape, and a gradual change gap is formed between the bottom of the second spring roller groove and the inner wall of the fourth unidirectional speed reducing device shell (4 c-5);

the buffer device comprises a second inner clamping table (4a-8) and a second buffer block (4a-4) which are positioned on the inner wall of the middle part of a second shell (3a), and a second outer clamping table (4a-7) which is positioned on the outer wall of the bottom of a fourth unidirectional speed reducer shell (4c-5), wherein the fourth unidirectional speed reducer shell (4c-5) is positioned in the second shell (3a), and a second hole (4a-10) in the second buffer block (4a-4) is sleeved on the second outer clamping table (4a-7) and positioned between the two second inner clamping tables (4 a-8).