CN114446716A

CN114446716A - Electromagnetic switch for starter

Info

Publication number: CN114446716A
Application number: CN202210154222.3A
Authority: CN
Inventors: 檀润华; 何川; 史帆
Original assignee: Hebei University of Technology
Current assignee: Hebei University of Technology
Priority date: 2022-02-21
Filing date: 2022-02-21
Publication date: 2022-05-06
Anticipated expiration: 2042-02-21
Also published as: CN114446716B

Abstract

The invention relates to an electromagnetic switch for a starter, which comprises a static contact, a moving contact, a first coil, a second coil, a small spring, a large spring and a push rod, wherein the first coil is arranged on the static contact; the third coil has been arranged in the left side of second coil, and the number of turns of second coil is greater than the number of turns of first coil, and the number of turns of first coil is greater than the number of turns of third coil, and the ampere force that receives left that the second coil is greater than big spring pulling force to the right, and three coil is restricted in corresponding region through corresponding spacing post on the electromagnetic switch casing respectively, is provided with boss structure on the push rod, at the fixed locking part in the space between two spacing posts in the region of third coil place. An arc extinguishing structure is designed in the contact area of the moving contact and the static contact. The electromagnetic switch can effectively improve the running stability of the starter, avoid collision of the driving gear and the gear ring caused by vehicle vibration running, and improve the stability of equipment. The arc extinguishing structure of the electromagnetic switch can effectively reduce the generation of electric arcs and improve the safety of equipment.

Description

Electromagnetic switch for starter

Technical Field

The invention relates to the technical field of automobile starters, in particular to an electromagnetic switch for a starter.

Background

The starter of the vehicle mainly comprises a direct current motor, a transmission mechanism, a control mechanism and other main parts. When the vehicle engine is started, the rotation torque generated by the direct current motor is transmitted to the gear ring of the engine flywheel through the driving gear of the transmission mechanism, so that the crankshaft of the vehicle engine is driven to rotate. The above process is a process of converting the electric energy provided by the vehicle battery into the mechanical energy, and the conversion process is realized by controlling the circuit on-off of the starter and the meshing and the disengagement of the driving gear and the gear ring by the control mechanism. Currently, a widely used starter control mechanism is an electromagnetic switch.

The electromagnetic switch can be divided into an integral type and a split type according to the form of the push rod. The electromagnetic switch applying the integral push rod has the defects that the push rod is large in size, so that the rigidity and inertia of the push rod are correspondingly increased, the situation that a large impact force is generated when the push rod moves is caused, and the long-term use of the electromagnetic switch generates large abrasion on equipment and reduces the service life, for example, the patent with the application number of PCT/CN 2013/077891. The electromagnetic switch of the split type push rod is used for effectively overcoming the defects of the integral push rod, but when the vehicle runs on bump and vibrates, the stability of the split type two push rod structures is relatively weak, and the mistaken touch and adhesion of the contact are easier to cause, such as the patent with the application number of 202020430893.4. The patent with application number 201922322060.6 provides an anti-gear-beating electromagnetic switch starter structure, the designed structure mainly solves the gear-beating problem when a driving gear and a gear ring are meshed, but the current flowing in an electromagnetic coil of a control push rod is large, so that the push rod retreating action has a hysteresis phenomenon, the driving gear and the gear ring are separated slowly to cause the damage of a contact surface, and the problem is not effectively solved. In addition, the electric arc that produces when current moving contact and static contact will cause the problem of burning, will cause the damage of equipment when serious.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides the electromagnetic switch for the starter, which can effectively improve the running stability of the starter, avoid the collision of a driving gear and a gear ring caused by the vibration running of a vehicle and improve the stability of equipment. In addition, the arc extinguishing structure of the electromagnetic switch can effectively reduce the generation of electric arcs and improve the safety of equipment.

In order to solve the technical problems, the invention adopts the technical scheme that:

in a first aspect, the invention provides an electromagnetic switch for a starter, which comprises a fixed contact, a moving contact, a first coil, a second coil, a small spring, a large spring and a push rod, wherein the first coil is arranged on the periphery of the moving contact rod in the radial direction; the method is characterized in that:

a third coil is arranged on the left side of the second coil, the number of turns of the second coil is greater than that of the first coil, the number of turns of the first coil is greater than that of the third coil, leftward ampere force borne by the second coil is greater than rightward pulling force of a large spring, the three coils are limited in corresponding areas through corresponding limiting posts on an electromagnetic switch shell respectively, the first coil, the second coil and the third coil are sequentially arranged from right to left, a boss structure is arranged on the push rod, a locking component is fixed in a space between the two limiting posts in the area where the third coil is located, in an initial state, the large spring gives rightward pulling force to the push rod, and the boss structure is located on the left side of the limiting portion of the locking component; when the third coil is conducted and the second coil is not conducted, the locking part moves upwards to release the limitation on the boss structure, and the push rod moves rightwards to enable the moving contact and the static contact to be gradually contacted; when the second coil is conducted, the second coil generates a leftward ampere force on the push rod after being conducted, and the magnitude of the ampere force is larger than the elastic force of the large spring, so that the push rod moves leftward to realize the separation of the drive gear and the gear ring; when the third coil is not conducted, the locking component falls down again and is clamped at the boss structure position to lock the push rod.

The static contact is connected with a battery, a direct current motor and a time relay in series, the time relay has the function of limiting the longest electrifying time of the circuit, if the circuit is always conducted due to the adhesion of the contact, the time relay automatically opens the circuit after reaching the preset time to ensure the safety of the equipment, and an external switch is connected between the battery and the third coil; the third coil is connected in series with a current-limiting resistor, and a circuit formed by the third coil and the current-limiting resistor in series is connected in parallel with a normally-open time-delay switch; the second coil is connected with a normally-closed time delay switch in parallel;

when the external switch is closed, the second coil is in a short-circuited state and cannot be switched on immediately, current flowing out of a power supply can flow through the normally closed delay switch firstly, the normally closed delay switch starts to work later than the external switch, the duration of the normally open delay switch is longer than that of the normally closed delay switch, and the loop of the third coil is also switched on when the external switch is closed.

The locking component comprises a locking block and a supporting seat, the locking block is triangular, the lower end of the locking block is provided with a convex rectangular block, the rectangular block is in mutual contact fit with a boss structure on the upper surface of the push rod, and the boss structure is positioned on the left side of the rectangular block at the lower end of the locking block when the electromagnetic switch does not work; the inclined plane of the left lower side of the locking block is attached to the supporting seat, the locking block can slide on the surface of the supporting seat through the matching of the guide rails and the supporting seat, the locking block and the supporting seat are in contact through a spring in a compressed state, and the spring generates rightward thrust to the locking block when the electromagnetic switch does not work.

In a second aspect, the present invention provides an electromagnetic switch for a starter, including two static contacts, two moving contacts, and two auxiliary contacts, wherein at least one of the static contacts is provided with an arc extinguish chamber, after the arc extinguish chamber is provided on the corresponding static contact, the arc extinguish chamber is also provided on the moving contact on the opposite surface, the arc extinguish chamber is integrated on the opposite surfaces of the corresponding moving contact and the static contact, and the auxiliary contacts operate independently of the arc extinguish chamber.

The invention provides an electromagnetic switch for a starter, which comprises two fixed contacts, a movable contact and auxiliary contacts, and is characterized in that the auxiliary contacts are arranged between the movable contact and the fixed contacts, the auxiliary contacts are used for contacting with contact platforms at corresponding positions in advance before the movable contact and the fixed contacts are contacted, and the movable contact and the fixed contacts are separated and then separated from the contact platforms at corresponding positions, and the electromagnetic switch is provided with at least two contact platforms and at least one auxiliary contact; at least one of the auxiliary contact or the contact platform is fixed with the moving contact, and at least one of the auxiliary contact or the contact platform is fixed with the fixed contact.

The static contact is trapezoidal or rectangular, a plurality of arc extinguish chambers are designed on the surface of the static contact opposite to the moving contact, the bottom of each arc extinguish chamber is divided into a plurality of small spaces by a plurality of grids, the moving contact is arranged on the left side opposite to the static contact, the arc extinguish chambers and the grids corresponding to the moving contact are designed on the surface of the moving contact opposite to the static contact, the arc extinguish chambers are in a structure with small surface openings and large inner spaces and comprise arc extinguish chamber openings, the arc extinguish chamber openings are small, a large space is arranged inside the arc extinguish chamber openings from the small arc extinguish chamber openings, the large inner spaces are divided into a plurality of small spaces by a plurality of grids for arc decomposition, and the areas and the lengths of all the arc extinguish chambers are not larger than the areas of the contacts and the lengths of the opposite contacts.

The opposite surfaces of the moving contact and the static contact are correspondingly provided with contact surfaces and arc extinguish chamber openings at intervals, namely the arc extinguish chambers on the contacts are arranged at intervals, electric arcs generated by the two contact surfaces during power-on contact can extend from the arc extinguish chamber openings of the arc extinguish chambers to the inner parts, and the electric arcs are further decomposed into smaller units through a plurality of grids at the bottom of the arc extinguish chambers; preferably, the contact position of the auxiliary contact and the contact platform is made of tellurium copper materials.

The electromagnetic switch is provided with two static contacts with the same structure, a moving contact and the two symmetrical static contacts form two opposite surfaces, a plurality of arc extinguish chambers with grids are arranged on the two opposite surfaces at intervals, contacts are welded on the opposite side surfaces of the two static contacts, the rightmost end of the moving contact is connected with an auxiliary contact through a bolt, the right end of the auxiliary contact is of a spread symmetrical flexible structure in the up-down direction, namely the auxiliary contact is of a Y-shaped structure, a trunk of the Y-shaped structure is fixed at the rightmost end of the moving contact through a bolt, and two branches of the Y-shaped structure are symmetrical and respectively extend to the side surfaces of the upper and lower static contacts to be contacted with the contacts; the two branches of the auxiliary contact and a contact platform welded on the side surface of the static contact are tightly attached and in sliding friction contact, the auxiliary contact is in contact with the contact platform in advance in the process that the moving contact moves rightwards to be in contact with the static contact, and the auxiliary contact is small in contact area and in soft landing contact, so that electric arcs cannot be generated, and a circuit connected with the two static contacts can be conducted in advance;

or the opposite side surfaces of the two static contacts are respectively provided with a contact platform, the rightmost end of the movable contact is welded with the contact platform, the upper part of the auxiliary contact is connected with the inner wall of the shell of the electromagnetic switch through a chute and a spring, the length of the chute is greater than that of the contact platform on the static contact, the left end of the chute is aligned with the height direction of the rightmost end of the movable contact, the auxiliary contact is in a U-shaped structure, the closed position of the U-shaped structure can slide in the chute, the contact platform on the movable contact can push the closed end of the auxiliary contact to slide in the chute, two support legs at the opening position of the U-shaped structure are respectively contacted with the contact platforms on the side surfaces of the two static contacts, the spring is arranged on the right side inside the chute, and the spring props against the closed position of the auxiliary contact installed in the chute;

or the auxiliary contact is welded on the side surfaces of the two static contacts, and the contact platform is connected to the rightmost end of the moving contact through a bolt;

or the contact surfaces of the auxiliary contact and the contact platform are not on the same horizontal plane, but are in a structure staggered with each other in space height, the auxiliary contact is connected to the rightmost end of the moving contact through a bolt and is higher than the contact platform welded on the side surface of the fixed contact, the lower surface of the flexible structure of the auxiliary contact is in mutual friction contact with the upper surface of the contact platform, the length from two support legs of the auxiliary contact to the symmetry center is larger than the distance from the side surface of the contact platform to the symmetry center of the auxiliary contact, and the lower surfaces of the support legs are in contact with the upper surface of the contact platform.

The electromagnetic switch is provided with two fixed contacts in different shapes, a plurality of arc extinguish chambers are arranged at intervals on the opposite surfaces of the fixed contact and the movable contact with larger cross section areas, the arc extinguish chambers are not arranged on the fixed contact with smaller cross section areas, auxiliary contacts and contact platforms are arranged on the opposite surfaces of the fixed contact and the movable contact with smaller cross section areas, and the number of the auxiliary contacts at the positions is multiple; in addition, the rightmost end of the moving contact is also connected with a contact platform through a bolt, and an auxiliary contact is welded on the opposite side surface between the static contact with a larger cross-sectional area and the contact platform at the rightmost end of the moving contact; preferably, the auxiliary contacts are respectively welded on the lower surface of the upper static contact and the lower surface of the movable contact, the cross-sectional area of the upper static contact is larger at this time, the rightmost end of the movable contact and the upper surface of the lower static contact are connected with a contact platform, only one side of the movable contact and one of the static contacts keep a complete contact surface and an arc extinguish chamber at this time, the other side of the movable contact and the other static contact only consist of a plurality of auxiliary contacts and contact platforms, the auxiliary contacts are sequentially contacted to complete a contact-post conductive process, the starting point of installation of the contact platform on the static contact is the leftmost end of the static contact, and the installation terminal point of the contact platform on the static contact is not less than the positions of the auxiliary contacts when the movable contact and the static contact are contacted;

or the auxiliary contact is welded on the side surfaces of the two fixed contacts, the rightmost end of the moving contact is connected with a contact platform through a bolt, the side surface of the moving contact is welded with a strip-shaped contact platform, and the length of the strip-shaped contact platform is consistent with that of the side surface.

In a fourth aspect, the invention also protects a starter using the electromagnetic switch for the starter.

Compared with the prior art, the invention has the advantages that:

the electromagnetic switch changes the conventional thought, does not consider the impact action generated when the driving gear and the gear ring are meshed (when the two are in contact meshing, the teeth of the two are meshed with each other accurately and quickly as much as possible), pays attention to the action of separating the driving gear and the gear ring, and the action of separating the two is quick, namely the driving gear is quickly extracted from the gear ring and keeps a certain distance after the extraction, so that the problems that the driving gear slowly withdraws from the gear ring for a long time and the position of the driving gear after the withdrawal is not fixed and secondary collision possibly occurs with the end face of the gear ring are avoided. According to the invention, the second coil 5 generates a leftward movement action on the push rod 11 after being electrified, the second coil 5 can generate a larger leftward Ampere force instantly, the Ampere force is larger than the elastic force of a corresponding spring, and meanwhile, a locking block structure is arranged, so that the rapid separation of the drive gear and the gear ring can be realized, the problem that the contact positions of the end surfaces of the drive gear and the gear ring and the edges of the gear can be damaged when the withdrawing action slowly moves in a contact-like and non-contact manner is solved, and the separation of the process that the push rod moves leftwards under the pushing action of the leftward force of the spring due to the fact that the coil of the push rod loses the rightward Ampere force due to power failure is also avoided, and the process is gradual and needs a period of time and is not instantaneous, so that the loss and the problem that the gear ring is separated from the drive gear are delayed are solved.

The arrangement of the locking block is matched with the third coil, so that the thrust of the coil is not increased at once, and when the push rod moves to the leftmost end, the locking block falls down through the third coil and is limited by the boss on the push rod, so that locking is realized. The anti-vibration structure ensures the stable position of the push rod when the vehicle runs on a bump and is impacted from the outside, and can effectively prevent the impact and the damage of the gear ring and the driving gear.

The third coil is controlled by a normally open delay switch, the second coil is controlled by a normally closed delay switch, and the third coil and the second coil can be quickly and automatically separated when the gear ring and the driving gear are meshed by matching with an anti-vibration structure, so that the damage to a contact surface when the gear ring and the driving gear are meshed in a high-speed rotating manner is reduced.

According to the invention, the arc extinguishing structure is designed in the contact area of the moving contact and the static contact, so that the arc extinguishing chamber and the corresponding moving contact and static contact are integrated together, the generation of electric arcs when the two contacts are in contact can be effectively reduced, and the operation safety of equipment is ensured. In addition, the arc extinguishing structure is provided with the auxiliary contact which is contacted in advance and separated finally, so that the generation of electric arcs is reduced to the maximum extent.

Drawings

Fig. 1 is a schematic view of the overall structure of an electromagnetic switch for a starter of the present invention;

FIG. 2 is a schematic view of the vibration-resistant structure of the electromagnetic switch for the starter of the present invention;

fig. 3 is a schematic view of an arc extinguishing structure embodiment 1 of the electromagnetic switch for the starter of the present invention;

fig. 4 is a schematic view of an arc extinguishing structure embodiment 2 of the electromagnetic switch for starter of the present invention;

fig. 5 is a schematic diagram of an arc extinguishing structure embodiment 3 of an electromagnetic switch for a starter according to the present invention and a schematic diagram of a mounting position of an auxiliary contact;

fig. 6 is a schematic view of an arc extinguishing structure embodiment 4 of the electromagnetic switch for the starter of the present invention;

fig. 7 is a schematic view of an arc extinguishing structure embodiment 5 of the electromagnetic switch for the starter of the present invention;

fig. 8 is a schematic view of an arc extinguishing structure embodiment 6 of the electromagnetic switch for the starter of the present invention;

FIG. 9 is a schematic diagram of a circuit arrangement for an electromagnetic switch for a starter of the present invention;

FIG. 10 is a schematic diagram of two coil control circuits of the electromagnetic switch for the starter of the present invention;

in the figure: 1. the device comprises a static contact rod, 2, a static contact, 3, a movable contact, 4, a first coil, 5, a second coil, 6, a small spring, 7, a large spring, 8, a third coil, 9, a locking block, 10, a supporting seat, 11, a push rod, 12, a shifting fork, 13, an isolator, 14, an output shaft, 15, a driving gear, 16, a speed reducer, 17, a direct current motor, 18, an auxiliary contact, 19, a gear ring, 20, a contact platform, 21, an arc extinguish chamber, 22, a grid, 23, a movable contact rod, 24, a current limiting resistor, 25, a battery, 26, a time relay, 27, an external switch, 28, a normally-open time delay switch, 29 and a normally-closed time delay switch.

Detailed Description

The invention is further explained below with reference to examples and figures.

The invention relates to an electromagnetic switch for a starter (referred to as an electromagnetic switch for short, and shown in figures 1-10) with good vibration resistance and arc extinguishing effect, which comprises a static contact rod 1, a static contact 2, a movable contact 3, a first coil 4, a second coil 5, a small spring 6, a large spring 7, a third coil 8, a locking block 9, a supporting seat 10, a push rod 11, a shifting fork 12, an isolator 13, an output shaft 14, a driving gear 15, a speed reducer 16, a direct current motor 17, an auxiliary contact 18, a gear ring 19, a contact platform 20, an arc extinguishing chamber 21, a grid 22, a movable contact rod 23, a current limiting resistor 24, a battery 25, a time relay 26, an external switch 27, a normally open time delay switch 28 and a normally closed time delay switch 29.

For the convenience of spatial position representation, it is now specified that the position of the second coil 5 relative to the first coil 4 is left, and the position of the push rod 11 relative to the output shaft 14 is up, as shown in fig. 1.

The static contact 2, the moving contact 3, the auxiliary contact 18 and the contact platform 20 are main components of an arc extinguishing structure, an arc extinguishing chamber is arranged on at least one opposite surface of the moving contact and the static contact, the arc extinguishing chambers are integrated on the corresponding moving contact and the static contact, the number of the static contacts is two, the arc extinguishing chambers can be arranged on at least one of the static contacts, and after the arc extinguishing chambers are arranged on the corresponding static contacts, the arc extinguishing chambers are also correspondingly arranged on the moving contacts on the opposite surfaces. The auxiliary contact 18 is independent of the arc-extinguishing chamber, and the auxiliary contact and the arc-extinguishing chamber are not connected to work independently.

The right end of the static contact rod 1 of the electromagnetic switch is connected with the direct current motor 17 through a lead, and the two static contact rods 1 are respectively connected with the positive pole and the negative pole of the lead, and are not distinguished here. The left end of the static contact rod 1 is connected with the static contact 2 through a bolt, the static contact 2 is trapezoidal or rectangular, a plurality of arc extinguish chambers 21 are designed on the surface of the static contact 2 opposite to the moving contact 3, the bottom of each arc extinguish chamber 21 is divided into a plurality of small spaces by a plurality of grids 22, the moving contact 3 is arranged on the left side opposite to the static contact 2, the arc extinguish chambers 21 and the grids 22 corresponding to the moving contact 3 are designed on the surface of the moving contact 3 opposite to the static contact 2, the number of the arc extinguish chambers or the specific number of the grids on the moving contact and the static contact are not required, and the function of decomposing or dividing arcs can be achieved. The shape of explosion chamber 21 is the structure that the little but inner space of surface opening is big, including the explosion chamber opening, the explosion chamber opening is less, gets into inside from less explosion chamber opening and has great space, and great inner space is cut apart into a plurality of little spaces by the grid of a plurality of quantity and is used for decomposing electric arc, and the area and the length of all explosion chambers all are not greater than the area of contact and the length of contact opposite face.

The opposite surfaces of the moving contact 3 and the static contact 2 (namely the surfaces of the positions where the moving contact and the static contact can be contacted with each other) are correspondingly provided with a contact surface and an arc extinguish chamber opening at intervals, namely the arc extinguish chambers on the contacts are arranged at intervals. Electric arcs generated by the two contact surfaces during power-on contact can be extended from the opening of the arc extinguish chamber 21 to the inside, the electric arcs are further decomposed into smaller units through the grids 22 at the bottom of the arc extinguish chamber 21, the decomposed electric arcs are weakened in energy and reduced in heat, equipment cannot be punctured or burnt, the electromagnetic switch is protected, and the function of expanding the contact surface area of the moving contact and the static contact is achieved through the structural design.

In order to further reduce electric arcs which are possibly generated when the movable contact 3 and the static contact 2 are suddenly and violently collided in a large-area contact manner, an auxiliary contact is arranged between the movable contact and the static contact, the auxiliary contact is used for contacting a contact platform at a corresponding position in advance before a main contact is contacted, the main contact is separated from the contact platform at the corresponding position after being separated, and the main contact is an auxiliary contact relative to the auxiliary contact, wherein the contact of the auxiliary contact and the contact platform is the auxiliary contact, and the contact of the movable contact and the static contact is the main contact.

The moving and static contacts, the auxiliary contacts 18 and the contact platform 20 have various connection modes as long as the above requirements can be met, and several feasible connection modes are provided below.

As shown in fig. 3, the connection mode is embodiment 1, there are two static contacts with the same structure, the static contacts are trapezoidal, the moving contact is triangular, the moving contact and the two symmetrical static contacts form two opposite faces, a plurality of arc-extinguishing chambers with grids are arranged on the two opposite faces at intervals, contacts are welded on the opposite side faces of the two static contacts, an auxiliary contact 18 is connected to the rightmost end of the moving contact 3 by a bolt, the right end of the auxiliary contact 18 is a symmetrical flexible structure which is unfolded in the up-down direction, that is, the auxiliary contact is in a Y-shaped structure, the trunk of the Y-shaped structure is fixed to the rightmost end of the moving contact by a bolt, and two branches of the Y-shaped structure are symmetrical and extend to the contact platforms on the side faces of the two static contacts. The two branches of the auxiliary contact are closely attached and in sliding frictional contact with the contact platform 20 welded on the side surface of the static contact 2. In the process that the moving contact 3 moves rightwards to be in contact with the static contact 2, the auxiliary contact 18 is in contact with the contact platform 20 in advance, and due to the fact that the contact area is small and the contact is soft landing contact, electric arcs cannot be generated, and a circuit connected with the two static contacts 2 can be conducted in advance. When the moving contact 3 continues to move rightwards to be jointed with the contact surface of the static contact 2, the arc extinguishing chamber 21 and the grid 22 further counteract the electric arc.

The flexible structure refers to a material with not very high rigidity, such as copper, the copper material with relatively low rigidity can play a role in buffering, rigid impact is avoided, and the top end of the auxiliary contact, namely the position where the auxiliary contact 18 is in contact with the contact platform 20, is made of a tellurium copper material.

As shown in fig. 4, the connection mode is embodiment 2, there are two static contacts of different shapes, a plurality of arc-extinguishing chambers are arranged at intervals on the opposite surfaces of the static contact and the moving contact with larger cross-sectional areas, no arc-extinguishing chamber is arranged on the static contact with smaller cross-sectional areas, and an auxiliary contact and a contact platform are arranged on the opposite surfaces of the static contact and the moving contact with smaller cross-sectional areas, and the number of the auxiliary contacts at this position is multiple, which can play a role similar to the arc-extinguishing chambers. In addition, the rightmost end of the moving contact 3 is also connected with a contact platform 20 through a bolt, and an auxiliary contact is welded on the opposite side surface between the static contact with larger cross section area and the contact platform at the rightmost end of the moving contact.

More specifically, the auxiliary contacts 18 are respectively welded to the lower surface of the upper fixed contact 2 and the lower surface of the movable contact 3, the cross-sectional area of the upper fixed contact is larger, the rightmost end of the movable contact 3 and the upper surface of the lower fixed contact 2 are connected to the contact platform 20, only one side of the movable contact 3 and one fixed contact 2 retain a complete contact surface and an arc extinguish chamber 21, the other side of the movable contact 3 and the other fixed contact 2 are only composed of the auxiliary contacts 18 and the contact platform 20, and the auxiliary contacts are sequentially contacted with each other, so that electric arcs are not generated, and the conductive process after contact is completed. At the moment, the starting point of installation of the contact platform on the static contact is the leftmost end of the static contact, and the installation end point of the contact platform on the static contact is not less than the positions of the auxiliary contacts when the static contact is contacted with the static contact.

As shown in fig. 5, the connection mode is embodiment 3, in this embodiment, the movable and stationary contacts have the same shape as embodiment 1, contact bases 20 are respectively disposed on opposite side surfaces of the two stationary contacts 2, meanwhile, the contact base is welded to the rightmost end of the movable contact 3, and the upper portion of the auxiliary contact 18 is connected to the inner wall of the housing of the electromagnetic switch through a chute and a spring. The length of spout is greater than the length that touches the platform on the static contact, and the left end of spout aligns with the rightmost end direction of height of moving contact, auxiliary contact is U style of calligraphy structure, and the closed position of U style of calligraphy structure can slide in the spout, and touches the platform on the moving contact and can promote auxiliary contact's blind end and slide in the spout, and two stabilizer blades of U style of calligraphy structure open position contact with the platform that touches of two static contact side respectively, at the inside right side installation spring of spout, this spring withstands the auxiliary contact closed position of installing in the spout. In the process that the moving contact moves rightwards, a contact platform on the moving contact is firstly contacted with the closed position of the U-shaped structure of the auxiliary contact 18 and then pushes the auxiliary contact to slide rightwards in the sliding groove, the spring is compressed in the process, when the contact platform is separated, the auxiliary contact moves rightwards under the action of the spring to be matched with the separation of the main contact, and the contact platform is separated from the auxiliary contact after the main contact is separated. And when the auxiliary contact is positioned at the leftmost end of the sliding groove, the auxiliary contact is not contacted with the two contact platforms on the fixed contact.

As shown in fig. 6, the connection mode is embodiment 4, in this embodiment, the shape of the moving and stationary contacts is the same as that of embodiment 2, the auxiliary contact 18 is welded on the side surfaces of the two stationary contacts 2, the rightmost end of the moving contact 3 is connected with a contact platform 20 through a bolt, the side surface of the moving contact 3 is welded with a strip-shaped contact platform, the length of the strip-shaped contact platform is the same as that of the side surface, the shapes of the stationary contact 2 and the moving contact 3 are changed correspondingly and are the same as those described in embodiment 2, and details are not repeated here.

As shown in fig. 7, the connection mode is embodiment 5, the auxiliary contact 18 is welded on the side surface of the two stationary contacts 2, and the contact platform 20 is connected to the rightmost end of the movable contact 3 through a bolt. In the five groups of embodiments, the contact surfaces of the auxiliary contacts and the contact platform are in the same horizontal plane, namely, the tail ends of the auxiliary contacts are directly in the same horizontal plane with the side surface of the contact platform.

As shown in fig. 8, the connection mode is embodiment 6, different from the five previous embodiments, the forms of the moving contact and the static contact are the same as those of embodiment 1, the contact surfaces of the auxiliary contact 18 and the contact platform 20 are not on the same horizontal plane, but are staggered in space height, the auxiliary contact 18 is connected to the rightmost end of the moving contact 3 through a bolt and is higher than the contact platform 20 welded to the side surface of the static contact 2, the lower surface of the flexible structure of the auxiliary contact 18 is in mutual frictional contact with the upper surface of the contact platform 20, the left end of the auxiliary contact is connected with the rightmost end of the moving contact through a bolt, the right end of the auxiliary contact is arc-shaped, the two ends of the arc are two legs, and the length from the two legs to the symmetry center thereof is greater than the distance from the side surface of the contact platform to the symmetry center of the auxiliary contact, so that the lower surfaces of the legs are in contact with the upper surface of the contact platform.

While the above-mentioned auxiliary contacts 18 and contact platforms 20 have various connection and combination manners, those skilled in the art can easily understand many structural design manners, such as placing the auxiliary contacts 18 under the contact platforms 20 in the embodiment 6, or connecting the auxiliary contacts 18 to the stationary contacts 2 and the contact platforms 20 to the movable contacts 3, and other modified structures. The present invention is only exemplary to develop the above six connection modes, but it is obvious that the protection scope of the arc extinguishing structure of the present invention is not limited to these six connection modes.

The basic requirements in the embodiments described above in setting up the auxiliary contacts and the contact pad contact are a small area, non-impact, non-rigid soft landing.

The left end of the moving contact 3 is connected with a moving contact rod 23 through a bolt, a small spring 6 is connected to the left end face of the moving contact rod 23, a push rod 11 is arranged on the left side of the moving contact rod 23 at the coaxial line position, and a large spring 7 is connected to the right end face of the push rod 11 and is in a stretching state. The movable contact rod 23 and the push rod 11 are connected to the electromagnetic switch housing through respective bushings, and both are slidable in the respective bushings (not shown) in the left and right directions freely. The moving contact rod 23 and the push rod 11 are generally made of non-magnetic material, such as copper alloy, copper, stainless steel, etc., so as not to adversely affect the magnetic circuit generated by the electromagnetic coil. The moving contact 3, the static contact 2 and the auxiliary contact 18 need to have good conductive performance, so the invention selects tellurium copper alloy material, the material has good machinability and excellent conductive and heat-conducting performance, simultaneously has corrosion resistance and electric ablation resistance, is easy to process and cast, the processing performance is convenient for manufacturing complex shapes such as the arc extinguish chamber 21 and the grid 22, and the effect of the electric arc generation resistance of the material is obvious. Because three kinds of contacts are frequent friction contact spare and easily wear and tear, so preferably pass through bolted connection between each contact and the feeler lever to change and maintain in the later stage, also can select the welding mode to connect when installation space is less, convenient processing.

The leftmost end of the push rod 11 is hinged with the upper end of a shifting fork 12, the middle part of the shifting fork 12 is connected to the electromagnetic switch shell through a hinge, and the lower part of the shifting fork 12 is connected with the right end of an output shaft 14 in a matched mode. The left end of the output shaft is sleeved with a one-way clutch 13 and a driving gear 15 respectively in the radial direction, and the driving gear 15 is in meshing contact with a gear ring 19 of a flywheel of a vehicle engine. The right side of the output shaft 14 is connected to a dc motor 17 via a reduction gear 16.

The periphery of the moving contact rod 23 in the radial direction is provided with a first coil 4, the left side of the first coil 4 is provided with a second coil 5, and the second coil 5 is positioned in the peripheral radial direction of the large spring 7. Third coil 8 that the number of turns has still less has been arranged in the left side of second coil 5, third coil 8 is located the upside of locking piece 9 in the space, and three coil is restricted in corresponding region through corresponding spacing post on the electromagnetic switch casing respectively, and first coil, second coil and third coil set gradually from right side to left side, fixes supporting seat 10 in the space between two spacing posts in third coil place region, supporting seat 10 passes through the bolt and links to each other with the electromagnetic switch casing and restricts the supporting seat position. The locking piece 9 is triangular and has a convex rectangular block at the lower end, the rectangular block is in mutual contact and matching with the boss structure on the upper surface of the right end of the push rod 11, and the boss structure is positioned on the left side of the rectangular block at the lower end of the locking piece 9 when the electromagnetic switch does not work. The inclined plane of the left lower side of the locking block 9 is attached to the supporting seat 10, a guide rail is arranged between the two to be matched, so that the locking block 9 can slide on the surface of the supporting seat 10, and the two are in contact with a spring in a compressed state, and the spring generates right thrust to the locking block 9 when the electromagnetic switch does not work. The locking block 9, the supporting seat 10 and the boss structure on the upper surface of the rear end of the push rod 11 form the main part of the anti-vibration structure. The space of the locking block 9 on the upper part, the left part and the right part of the electromagnetic switch shell is limited, namely the space of the electromagnetic switch shell limits the movement, the spring between the locking block 9 and the supporting seat 10 pushes the locking block 9 rightwards, but the locking block cannot fall down when limited by the electromagnetic switch shell; the locking piece 9 is connected with the supporting seat 10 through a guide rail, so that the locking piece 9 cannot run randomly.

As shown in the circuit schemes of the present invention shown in fig. 9 and 10, the stationary contact 2 is connected in series with a battery 25, a dc motor 17 and a time relay 26. The time relay 26 has the function of limiting the longest power-on time of the circuit, and if the circuit is always on due to the adhesion of the contacts, the time relay 26 automatically opens the circuit after reaching the preset time so as to ensure the safety of the equipment. An external switch 27 is connected between the battery 25 and the third coil 8. The third coil 8 is connected in series with a current-limiting resistor 24, and the series circuit of the current-limiting resistor and the current-limiting resistor is connected in parallel with a normally-open time-delay switch 28. The second coil 5 is connected with a normally closed time delay switch 29 in parallel.

The working process of the electromagnetic switch of the invention is as follows: when the external switch 27 is closed, the battery 25 is conducted, and after the first coil 4 is electrified, a rightward ampere force is generated on the movable contact rod 23, and the magnitude of the force is larger than the leftward force of the small spring 6, so that the movable contact rod 23 moves rightwards, and the auxiliary contact 18 arranged on the movable contact 3 is in contact with the contact platform 20 arranged on the static contact 2 in advance in the process of moving rightwards, and possible electric arcs are weakened. The moving contact rod 23 continues moving rightwards until the contact surfaces of the moving contact 3 and the static contact 2 are attached to each other, so that the complete conduction of the current between the two static contacts is realized, the current further flows through the direct current motor 17, the rotating torque output by the direct current motor 17 is transmitted to the output shaft 14 through the speed reducer 16, and the output shaft 14 can operate according to the rotating speed required by the starter.

When the external switch 27 is closed, the circuit of the third coil 8 is also conducted, and the leftward ampere force generated by the third coil 8 is greater than the rightward spring force of the supporting seat 10 to the locking piece 9, so that the locking piece 9 moves leftward. Meanwhile, due to the limiting effect of the inclined surface of the supporting seat 10, the locking block 9 moves leftwards and upwards at the same time, so that the rectangular block at the lower end of the locking block 9 is higher than the boss structure on the upper surface of the push rod 11, and the push rod 11 slides rightwards under the pulling force of the large spring 7 after getting rid of the limit of the locking block 9. The upper end of the shift fork 12 moves rightward along with the push rod 11, the output shaft 14 moves leftward along with the lower end of the shift fork 12, and the driving gear 15 installed at the leftmost end of the output shaft 14 also moves leftward and is in meshing contact with the ring gear 19 of the flywheel of the vehicle engine. Thus, the process that the electromagnetic switch controls the starter to operate and transmits the torque of the starter to the vehicle engine is realized.

Since the second coil 5 is connected in parallel with the normally closed delay switch 29, the second coil 5 is not immediately turned on in a short-circuited state when the external switch 27 is closed, and a current flowing from a power supply flows through the normally closed delay switch 29 first, and the normally closed delay switch starts to operate later than the external switch 27. Assuming that the time for which the normally-closed delay switch 29 is preset is three seconds, the normally-closed delay switch 29 is turned off three seconds after the external switch 27 is closed, and the second coil 5 can be turned on. After the second coil 5 is conducted, an ampere force towards the left is generated on the push rod 11, and the ampere force is larger than the elastic force of the large spring 7, so that the push rod 11 moves towards the left, and the lower end of the shifting fork 12 and the output shaft 14 move towards the right. The drive gear 15 disengages from the ring gear 19 and no longer meshes with the output shaft 14 as it moves to the right. Thus, the automatic separation process of the starter and the vehicle engine is realized.

The duration of the normally open delay switch 28 is greater than the duration of the normally closed delay switch 29, which is the time interval between the push rod beginning to move to the left and the lock block beginning to fall, assuming a five second setting in this embodiment, the switch 28 is turned on when the second coil 5 is turned on for two seconds and the push rod 11 is pushed to the leftmost end (when the push rod 11 is at the leftmost end, the rectangular portion at the lower end of the lock block 9 is located higher than the upper surface of the lock block 11 because the third coil 8 has a leftward ampere force on the lock block 9, the lock block 9 moves upward again under the guide of the support seat 10, but the upper surface of the lock block 9 has a space limitation of the rack, so the lock block 9 does not move upward all the time, i.e., the lower surface of the lock block 9 does not stop moving upward higher than the lower surface of the support seat 10.) the switch is turned on when the second coil 5 is normally opened two seconds later, and the third coil 8 is short-circuited and no longer operates. After the locking piece 9 loses the leftward ampere force provided by the third coil 8, the locking piece moves rightward and downward under the action of the rightward spring elastic force given by the supporting seat 10, so that the locking piece 9 clamps the boss structure on the upper surface of the push rod 11 again, the position stability of the push rod under the condition of vehicle jolt driving road is ensured, under the condition of power failure of the third coil 8, the locking piece loses the limitation of the third coil, the locking piece falls down along the supporting seat, the leftward ampere force of the second coil 5 is removed at the moment, and the force of the spring is received rightward, so that the push rod 11 can be buffered by a distance rightmost from the left end, and the locking piece is just clamped at the falling position of the locking piece. When the external switch 27 is closed, the first coil 4 is powered off, so that the movable contact rod 23 moves to the left under the action of the small spring 6 and causes the movable contact 3 and the fixed contact 2 to be separated, and the direct current motor 17 is powered off. Thus, the operation of the whole equipment in one complete period is realized.

The invention can realize the quick withdrawal of the driving gear: the structure for realizing the action is the action of moving leftwards generated by the push rod 11 after the second coil 5 is electrified, and the second coil 5 can generate larger leftwards ampere force instantly in the application, so that the number of turns of the arranged second coil is more and is larger than the number of turns of the first coil and the third coil. If the withdrawing action is slow to wander, damage must occur to the end faces of the drive gear 15 and the ring gear 19 and the edge contact positions of the teeth at the time of contact-like non-contact. In the prior art, the coil is electrified after the external switch is switched on, a rightward force is generated on the push rod, the coil loses the electricity after the external switch is switched off, the rightward ampere force is lost, and the push rod moves leftward under the pushing of the leftward force of the spring. However, the problem is that the second coil loses its ampere force due to the power failure gradually and in a non-instantaneous manner, because of the large number of turns and the large internal current, and cannot be withdrawn quickly. This application creatively carries out 180 upsets with the direction of force of big spring and second coil production, can produce great ampere's power left in the twinkling of an eye promptly after the second coil circular telegram promptly, and big spring pulling force right is obviously less than this ampere's power left for the push rod moves fast left, and the structure that has added locking piece 9 in time carries on spacingly to the push rod when the third coil does not switch on, realizes further stable function. The improved structure realizes that the driving gear is actively withdrawn from the gear ring, namely the second coil gives active and larger ampere force, and then the driving gear and the gear ring are actively separated.

In the present invention, with respect to the fixing of the position of the drive gear 15: the position stability of the driving gear is guaranteed after the driving gear rapidly retreats, namely, the driving gear cannot move left and right when a vehicle jolts or equipment vibrates, otherwise, the driving gear can collide with the gear ring, secondary collision or collision during vehicle running is caused, the gear ring rotates at high speed along with a vehicle engine, the driving gear does not rotate, and the gear ring and the engine cannot be damaged by collision. Therefore, the structure of the locking block 9 is designed, and the structure is matched with the third coil and the boss structures on the push rod to ensure that the drive gear cannot move left and right when the position of the right end, namely the position of the left end of the push rod 11, is at the right end.

The invention also realizes the automatic exit of the driving gear: the term "automatically" used herein means that after the device completes the starting of the vehicle engine, the driving gear will automatically exit, which depends on the normally closed delay switch 29 and the normally open delay switch 28 provided in the present application, the duration of the normally open delay switch 28 is longer than that of the normally closed delay switch 29, the normally open delay switch 28 controls the on-off of the third coil, the normally closed delay switch 29 controls the on-off of the second coil, the automatic exiting of the driving gear can be realized according to the time difference of the two switches without opening the external switch to exit the driving gear, thereby ensuring the stable and more controllable operation of the driving gear and the gear ring without being damaged and the device.

The structure of the upper half part in fig. 1 is the structure of an electromagnetic switch, the whole structure in fig. 1 is called the structure of a starter, and when a fixed contact and a movable contact are contacted, electric arcs occur, and the electric arcs are undesirable because the electric arcs can burn or break down equipment. The conditions for arc generation are mainly as follows: sudden, violent, large area impacts. In order to solve the problem of electric arc generation, the invention is provided with an auxiliary contact, a contact platform and an arc extinguish chamber. The auxiliary contact can be used for pre-contacting the small contact before large-area, sudden and violent impact between the fixed contact and the movable contact, namely, the auxiliary contact is pre-contacted before the main contact is contacted, and the auxiliary contact is separated finally after the main contact is separated. The auxiliary contact is in flexible contact, so that the condition of violent impact is avoided. Meanwhile, the invention is also provided with an arc extinguish chamber integrated with the contact. The auxiliary contacts extinguish a certain amount of electric arc, but when the two main contacts are in collision contact, the electric arc is also generated, the designed arc-extinguishing chamber aims to extinguish the electric arc, the generated electric arc is actively guided into a larger space after the electric arc is generated, the electric arc in the large space is decomposed through the grating 22 in a targeted manner, and the energy of the decomposed electric arc is weakened.

The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed.

Nothing in this specification is said to apply to the prior art.

Claims

1. An electromagnetic switch for a starter comprises a fixed contact, a movable contact, a first coil, a second coil, a small spring, a large spring and a push rod, wherein the first coil is arranged on the periphery of the movable contact rod in the radial direction; the method is characterized in that:

2. The electromagnetic switch for the starter as claimed in claim 1, wherein the static contact is connected in series with a battery, a dc motor and a time relay, the time relay functions to limit the longest power-on duration of the circuit, and when the circuit is always turned on due to the adhesion of the contacts, the time relay automatically opens to ensure the safety of the device after reaching a preset duration, and an external switch is connected between the battery and the third coil; the third coil is connected in series with a current-limiting resistor, and a circuit formed by the third coil and the current-limiting resistor in series is connected in parallel with a normally-open time-delay switch; the second coil is connected with a normally-closed time delay switch in parallel;

3. The electromagnetic switch for starter of claim 1 wherein the locking member comprises a locking piece and a support base, the locking piece is triangular and has a rectangular protruding piece at its lower end, the rectangular piece is in contact with and fitted to the boss structure on the upper surface of the push rod, and the boss structure is located on the left side of the rectangular piece at the lower end of the locking piece when the electromagnetic switch is not in operation; the inclined plane of the left lower side of the locking block is attached to the supporting seat, the locking block can slide on the surface of the supporting seat through the matching of the guide rails and the supporting seat, the locking block and the supporting seat are in contact through a spring in a compressed state, and the spring generates rightward thrust to the locking block when the electromagnetic switch does not work.

4. The electromagnetic switch for the starter comprises two static contacts, a moving contact and auxiliary contacts, and is characterized in that an arc extinguish chamber is arranged on at least one static contact, after the arc extinguish chamber is arranged on the corresponding static contact, the arc extinguish chamber is correspondingly arranged on the moving contact on the opposite surface, the arc extinguish chambers are integrated on the opposite surfaces of the corresponding moving contact and the static contacts, and the auxiliary contacts are independent of the arc extinguish chambers to work.

5. An electromagnetic switch for a starter comprises two static contacts, a movable contact and auxiliary contacts, and is characterized in that the auxiliary contacts are arranged between the movable contact and the static contacts, the auxiliary contacts are used for contacting with contact platforms at corresponding positions in advance before the movable contact and the static contacts are contacted, the movable contact and the static contacts are separated and then separated from the contact platforms at corresponding positions, and the electromagnetic switch is provided with at least two contact platforms and at least one auxiliary contact; at least one of the auxiliary contact or the contact platform is fixed with the moving contact, and at least one of the auxiliary contact or the contact platform is fixed with the fixed contact.

6. The electromagnetic switch for the starter according to claim 4 or 5, wherein the fixed contact is trapezoidal or rectangular, a plurality of arc-extinguishing chambers are designed on the surface of the fixed contact opposite to the movable contact, the bottom of each arc-extinguishing chamber is divided into a plurality of small spaces by a plurality of grids, the movable contact is arranged on the left side opposite to the fixed contact, the arc-extinguishing chambers and the grids corresponding to the fixed contact are designed on the surface of the movable contact opposite to the fixed contact, the arc-extinguishing chambers are in a structure with a small surface opening and a large internal space, and comprise arc-extinguishing chamber openings, the arc-extinguishing chamber openings are small, the arc-extinguishing chambers enter the inside from the small arc-extinguishing chamber openings and have a large internal space, the large internal space is divided into a plurality of small spaces by a plurality of grids for arc decomposition, and the areas and the lengths of all the arc-extinguishing chambers are not larger than the areas of the contacts and the lengths of the opposite surfaces of the contacts.

7. The electromagnetic switch of claim 6, wherein the opposing surfaces of the moving contact and the stationary contact are correspondingly and alternately provided with a contact surface and an arc extinguish chamber opening, that is, the arc extinguish chamber on the contact is alternately provided, and the arc generated by the two contact surfaces during the electrical contact will extend from the arc extinguish chamber opening of the arc extinguish chamber to the inside, and further decompose the arc into smaller units through a plurality of grids at the bottom of the arc extinguish chamber; preferably, the contact position of the auxiliary contact and the contact platform is made of tellurium copper materials.

8. The electromagnetic switch for the starter according to claim 4 or 5, wherein the electromagnetic switch has two fixed contacts of the same structure, the movable contact and the two symmetrical fixed contacts form two opposite faces, a plurality of arc-extinguishing chambers with grids are arranged on the two opposite faces at intervals, contacts are welded on the opposite side faces of the two fixed contacts, an auxiliary contact is connected to the rightmost end of the movable contact through a bolt, the right end of the auxiliary contact is of a symmetrical flexible structure which is unfolded in the up-down direction, namely the auxiliary contact is of a Y-shaped structure, a main body of the Y-shaped structure is fixed to the rightmost end of the movable contact through a bolt, and two branches of the Y-shaped structure are symmetrical and respectively extend to the side faces of the upper and lower fixed contacts to be contacted with the contacts; the two branches of the auxiliary contact and a contact platform welded on the side surface of the static contact are tightly attached and in sliding friction contact, the auxiliary contact is in contact with the contact platform in advance in the process that the moving contact moves rightwards to be in contact with the static contact, and the auxiliary contact is small in contact area and in soft landing contact, so that electric arcs cannot be generated, and a circuit connected with the two static contacts can be conducted in advance;

9. The electromagnetic switch for the starter according to claim 4 or 5, wherein the electromagnetic switch has two fixed contacts of different shapes, a plurality of arc-extinguishing chambers are arranged at intervals on the opposite surfaces of the fixed contact and the movable contact with larger cross-sectional areas, no arc-extinguishing chamber is arranged on the fixed contact with smaller cross-sectional areas, and auxiliary contacts and contact platforms are arranged on the opposite surfaces of the fixed contact and the movable contact with smaller cross-sectional areas, and the number of the auxiliary contacts at the positions is multiple; in addition, the rightmost end of the moving contact is also connected with a contact platform through a bolt, and an auxiliary contact is welded on the opposite side surface between the static contact with a larger cross-sectional area and the contact platform at the rightmost end of the moving contact; preferably, the auxiliary contacts are respectively welded on the lower surface of the upper static contact and the lower surface of the movable contact, the cross-sectional area of the upper static contact is larger at this time, the rightmost end of the movable contact and the upper surface of the lower static contact are connected with a contact platform, only one side of the movable contact and one of the static contacts keep a complete contact surface and an arc extinguish chamber at this time, the other side of the movable contact and the other static contact only consist of a plurality of auxiliary contacts and contact platforms, the auxiliary contacts are sequentially contacted to complete a contact-post conductive process, the starting point of installation of the contact platform on the static contact is the leftmost end of the static contact, and the installation terminal point of the contact platform on the static contact is not less than the positions of the auxiliary contacts when the movable contact and the static contact are contacted;

10. A starter using the electromagnetic switch for a starter according to any one of claims 1 to 9.