阅读说明：本技术 一种触片组件及基于该触片组件的保护器 (Contact piece assembly and protector based on contact piece assembly ) 是由 成明生 顾杰 于 2020-11-17 设计创作，主要内容包括：本发明属于锂电池用敏感保护元器件技术领域,特别涉及一种触片组件及基于该触片组件的保护器,触片组件包括触片和触点,触点为片状结构,触点的片面在尺寸上小于触片的片面,触点整体面面贴合复合于触片的其中一个片面上,触点的片厚为0.03～0.07mm,对触点和触片所形成的整体进行冲顶,从而使该整体形成凸起。保护器包括绝缘座、动触片组件、静触片组件、PTC放置槽、PTC发热元件、感温元件、盖板,其中,动触片组件采用本申请中的触片组件。(The invention belongs to the technical field of sensitive protection components for lithium batteries, and particularly relates to a contact piece assembly and a protector based on the contact piece assembly, wherein the contact piece assembly comprises a contact piece and a contact, the contact is of a sheet structure, the sheet surface of the contact is smaller than the sheet surface of the contact piece in size, the whole surface of the contact is laminated and compounded on one sheet surface of the contact piece, the sheet thickness of the contact is 0.03-0.07 mm, and the whole formed by the contact piece and the contact piece is punched to form a bulge. The protector includes insulator foot, movable contact piece subassembly, quiet contact piece subassembly, PTC standing groove, PTC heating element, temperature-sensing element, apron, and wherein, movable contact piece subassembly adopts the contact piece subassembly in this application.)

1. A wafer assembly, comprising: the contact piece assembly comprises a contact piece (1) and a contact (2), the contact (2) is of a sheet structure, the size of the sheet surface of the contact (2) is smaller than that of the sheet surface of the contact piece (1), the whole surface of the contact (2) is attached and compounded on one sheet surface of the contact piece (1), and the sheet thickness of the contact (2) is 0.03-0.07 mm.

2. The contact blade assembly of claim 1, wherein: the contact piece (1) and the contact (2) integrally form a bulge outwards, the bulge is formed towards the direction of the contact (2), and the bulge is perpendicular to the sheet surface of the contact (2) and/or the sheet surface of the contact piece (1) in the direction.

3. A protector for contact blade assemblies according to claim 1 or 2, wherein: the protector comprises an insulating seat (3), a movable contact piece component (4), a static contact piece component (5), a PTC placing groove (31), a PTC heating element (6), a temperature sensing element (7) and a cover plate (8),

the movable contact piece component (4) is the contact piece component of claim 1 or 2, namely, the contact piece (1) in the movable contact piece component (4) is a movable contact piece, the contact (2) is a movable contact, and the static contact piece component (5) comprises a static contact piece (51) and a static contact (52).

4. A protector according to claim 3, characterised in that: the partial section of the static contact piece (51) is positioned at the bottom of the insulating seat (3) and fixedly connected with the insulating seat (3), the PTC placing groove (31) is arranged on the insulating seat (3) and positioned above the static contact piece (51), the groove bottom of the PTC placing groove (31) is communicated with the upper piece surface of the static contact piece (51), the PTC heating element (6) is arranged in the PTC placing groove (31) in a matching way,

the temperature sensing element (7) is arranged above the PTC heating element (6), the moving contact piece is arranged above the temperature sensing element (7), and the moving contact and the fixed contact (52) are abutted and contacted or separated with each other under the supporting state of the temperature sensing element (7) to the moving contact piece,

the cover plate (8) is arranged above the movable contact spring, and the cover plate (8) is matched with the insulating seat (3) to form a closed space.

5. A protector according to claim 3, characterised in that: the cover plate (8) comprises a supporting piece (81), the supporting piece (81) is fixed to the lower portion of the cover plate (8), two downward protruding points are arranged on the surface of the supporting piece (81), the two downward protruding points are a first point (811) and a second point (812) respectively, the protruding degree of the first point (811) is larger than that of the second point (812), the first point (811) abuts against the first section of the movable contact, and the second point (812) abuts against or breaks the second section of the movable contact.

6. A protector according to claim 3, characterised in that: the static contact piece (51) is of a bending structure, the bending structure comprises a first edge, a second edge and a third edge, one end of the first edge in the length direction of the first edge is connected with one end of the third edge in the length direction of the third edge through the second edge, and the first edge is located at the bottom of the insulating seat (3).

7. The protector of claim 6, wherein: the static contact piece (51) is provided with a supporting point (511) protruding upwards on the surface of the first edge area, and the supporting point (511) is abutted to the bottom of the PTC heating element (6) upwards.

8. A protector according to claim 3, characterised in that: two downward convex points which are distributed in a row along the length direction of the movable contact are arranged on the surface of the movable contact piece far away from the movable contact, the downward convex points are respectively a first contact point (41) and a second contact point (42), the first contact point (41) and the second contact point (42) are respectively abutted against or disconnected with the upper part of the temperature sensing element (7), and the first contact point (41) and the second contact point (42) are smaller than the movable contact in volume.

9. The protector of claim 8, wherein: and a movable connection point (43) is arranged on the movable contact piece between the first contact point (41) and the second contact point (42) along the length direction of the movable contact piece.

10. A protector according to claim 3, characterised in that: the periphery of the cover plate (8) is provided with a small protruding welding point for ultrasonic welding, and the cover plate (8) and the insulating base (3) form a closed space through ultrasonic welding.

Technical Field

The invention belongs to the technical field of sensitive protection components for lithium batteries, and particularly relates to a contact piece assembly and a protector based on the contact piece assembly.

Background

The load and the protector are generally connected in series in the circuit to protect the load, the load normally works, namely when current flows normally, a static contact on a static contact piece and a movable contact on a movable contact piece in the protector are abutted and contacted with each other, and when the current is overloaded, the temperature of the protector rises and pushes the static contact and the movable contact to be separated from each other through the deformation of the temperature sensing element.

In the prior art, a contact is welded on a contact to realize fixation, but due to the limitation of a welding process, the contact is required to have a certain thickness, the thickness of the contact is generally at least more than 0.2mm, the contact is welded or riveted to deform due to too thin, but the thickness of the contact is increased, so that the thickness and the volume of the whole protector are correspondingly increased, the protector is not suitable for lithium batteries, particularly batteries for portable electronic products such as mobile phones, notebooks and the like, and the protector is inconvenient to mount due to the small volume of the batteries. In addition, because the sufficient current of the battery is large and can reach more than 25A at most, the contact area between the contact and the contact is small during welding connection, the current flowing capacity is limited, the protector generates heat, the action temperature of the protector is abnormal, and the normal use of the battery is influenced.

Disclosure of Invention

In order to solve the technical problems, the invention provides a contact piece assembly, which comprises a contact piece and a contact, wherein the contact is of a sheet structure, the size of the sheet surface of the contact is smaller than that of the sheet surface of the contact piece, the whole surface of the contact is combined on one sheet surface of the contact piece in a fitting manner, the sheet thickness of the contact is 0.03-0.07 mm, the contact and the contact piece can be combined together in a thermal combination manner (such as warm rolling and the like),

the contact is made of silver-nickel alloy (AgNi10), is called silver layer for short, has better arc discharge resistance under low voltage and large current (such as DC 9V-25A), can adopt high-conductivity copper for the contact, and has the advantages of low price, low temperature rise and good conductivity;

preferably, the method comprises the following steps: after the contact and the contact piece are combined, the whole formed by the contact and the contact piece is punched, so that the whole is protruded towards the silver layer, the direction of the protrusion is vertical to the surface of the contact and/or the contact piece,

the formation of the bulge is beneficial to maintaining the contact form of point surface or line surface between the movable contact and the fixed contact, so as to ensure that enough pressure (compared with the contact between a plane and a plane) is provided for the contact, improve the contact reliability, reduce the instability on the contact position when the movable contact and the fixed contact are contacted after being separated, further reduce the occurrence of ignition phenomenon and avoid burning out,

as shown in the attached drawings, the height of the convex part is 0.1 mm-0.12 mm, compared with the thickness (more than 0.2mm at least) of the traditional welding type contact, the thickness and the volume of the whole protector are also reduced correspondingly,

the contact silver layer and the contact sheet are compounded through a warm rolling process and then are punched, the contact silver layer and the contact sheet are synchronously bent and raised, meanwhile, the applicant practices and finds that after punching deformation, the binding force between the silver layer and the contact sheet is not weakened but enhanced, the service life is further ensured,

according to the scheme, rolling type rolling compaction is adopted for realizing warm rolling compounding, the warm rolling compounding temperature is 550-700 ℃, the pressure of the warm rolling compounding is about 10 tons, and 8-12 tons are preferred; the top punching operation is carried out based on the principle of smooth extrusion and half-stretching, a punch with a spherical structure is adopted, and the top punching pressure is 25-30 tons.

The invention also provides a protector based on the contact piece component, which comprises an insulating seat, a movable contact piece component, a static contact piece component, a PTC placing groove, a PTC heating element, a temperature sensing element and a cover plate, wherein the movable contact piece component and the static contact piece component can both adopt the contact piece component in the invention, or one of the movable contact piece component and the static contact piece component adopts the contact piece component in the invention,

the partial section of the static contact is positioned at the bottom of the insulating seat and fixedly connected with the insulating seat (integrally injection-molded with the insulating seat), the PTC placing groove is arranged on the insulating seat and positioned above the static contact, the groove bottom of the PTC placing groove is communicated with the upper surface of the static contact, the PTC heating element is arranged in the PTC placing groove in a matching way,

the temperature sensing element is arranged above the PTC heating element, the moving contact piece is arranged above the temperature sensing element, the moving contact and the fixed contact are contacted or separated with each other in the supporting state of the temperature sensing element to the moving contact piece,

the cover plate is arranged above the movable contact spring and forms a closed space by matching with the insulating seat,

preferably, the method comprises the following steps: the cover plate comprises a supporting sheet fixed at the lower part of the cover plate, two downward convex points are arranged on the sheet surface of the supporting sheet, the two downward convex points are respectively a first point and a second point, the first point is larger than the second point in the convex degree, the first point is abutted against the first section of the movable contact spring, the second point is abutted against or disconnected from the second section of the movable contact spring,

preferably, the method comprises the following steps: the static contact is a bending structure and is fixedly connected with the insulating seat (integrally injection-molded with the insulating seat), the bending structure comprises a first edge, a second edge and a third edge, one end of the first edge along the length direction of the first edge is connected with one end of the third edge along the length direction of the first edge through the second edge, the first edge is positioned at the bottom of the insulating seat,

preferably, the method comprises the following steps: the surface of the static contact piece positioned in the first edge area is provided with a supporting point which protrudes upwards and is propped against the bottom of the PTC heating element upwards,

preferably, the method comprises the following steps: two downward convex points which are distributed along the length direction of the movable contact piece and are respectively a first contact point and a second contact point are arranged on the surface of the movable contact piece far away from the movable contact point, the first contact point and the second contact point are respectively abutted against or disconnected with the upper part of the temperature sensing element, the first contact point and the second contact point are both smaller than the movable contact point in volume,

preferably, the method comprises the following steps: on the movable contact piece, a movable connection point is arranged between the first contact point and the second contact point along the length direction of the movable contact piece,

preferably, the method comprises the following steps: the periphery of apron is provided with the small protruding welding point that is used for ultrasonic bonding, and the insulating seat is the ship shape structure, and the apron passes through ultrasonic bonding with the insulating seat and forms the enclosure space, and the apron is fixed a position and is connected the movable contact piece joint in the constant head tank of apron through locating pin and movable contact piece.

The main design points of the invention are as follows:

the silver-nickel alloy section with the sheet structure is hot-pressed and compounded on the sheet surface of the contact piece to be used as a contact to replace the traditional welding contact, and the thickness of the contact is obviously reduced even after the protrusion is formed by punching, so that the thickness and the volume of a protector to which the contact piece component belongs are correspondingly reduced, and the operability of the protector when the protector is installed in an equipment circuit is improved;

the contact silver layer and the contact sheet are compounded through a warm rolling process and then deformed through punching, the interlayer bonding force is stable, the service life is ensured, the protector manufactured based on the contact sheet assembly can pass a DC 9V-25A 10000 times of electric life detection test, and the contact part between the contact silver layer and the contact sheet is not abnormal after the detection test;

meanwhile, as the contact is compounded on the contact in a sheet form, compared with the traditional welding type contact, the contact area between the contact and the sheet surface of the contact is greatly increased, so that the current conducting capacity of the contact and the contact part of the contact is increased (as the current conducting capacity at the position is influenced by the contact area between the contact and the contact, the horizontal size of the contact is large enough for the traditional welding type contact, the large-area contact with the contact can be realized, but as mentioned above, the welding has the requirement on the thickness of the contact, and the increase of the horizontal size of the contact on the basis can cause the material consumption of the contact to be greatly increased, so that the material cost is correspondingly increased.

Drawings

Fig. 1 is a schematic structural view (in front cross section) of the contact assembly of the present invention, before punching the top of the overall layer structure formed by the contacts and contacts,

fig. 2 is a schematic diagram (front cross-sectional view) of the bump-formed structure of the contact and contact of the contact assembly of the present invention,

figure 3 is a schematic view (front view) of the internal structure of the protector in the closed state of the invention,

figure 4 is a schematic view (front view) of the internal structure of the protector in the open state of the invention,

fig. 5 is a schematic structural view (front view) of the moving contact assembly in the protector of the present invention.

Wherein, 1-contact, 2-contact, 3-insulation base, 31-PTC placement groove, 4-movable contact piece, 41-first contact, 42-second contact, 43-movable connection point, 44-first section of movable contact, 45-second section of movable contact, 5-static contact piece, 51-static contact piece, 511-support, 52-static contact, 6-PTC heating element, 7-temperature sensing element, 8-cover, 81-support, 811-first point, 812-second point.

Detailed Description

It should be noted that the words "left" and "right" used in the description of the present invention refer to directions in fig. 3, 4 and 5, and "inner" and "outer" refer to directions toward and away from, respectively, the geometric center of a particular component, which are merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention.

Example 1

As shown in fig. 1 and 2, the contact assembly of the present invention includes a contact 1 and a contact 2, the contact 1 is a conventional sheet-like contact, except that the contact 2 is also a sheet-like structure (hereinafter also referred to as "silver layer"), the sheet surface of the contact 2 is smaller in size than the sheet surface of the contact 1, the whole surface of the contact 2 is bonded and compounded on one of the sheet surfaces of the contact 1 near the edge, in the finished contact assembly, the thickness of the contact 2 is 0.05mm,

the compound technology is that rolling type rolling compaction is adopted to realize warm rolling compounding, the warm rolling compounding temperature is 600 ℃, the pressure of the warm rolling compounding is 10 tons, on the basis, the whole formed by the contact 2 and the contact sheet 1 is jacked, so that the whole forms an outward bulge, the bulge faces to the silver layer direction, the bulge direction is perpendicular to the sheet surface of the contact 2 and/or the contact sheet 1, a punch is of a spherical structure, the area is 0.75 x 1, the jacking pressure is 25 tons, and the height of the bulge is controlled to be 0.1mm through the jacking depth.

And (3) performing a thermal shock test on the composite layer convex structure obtained after the top punching:

the resulting wafer assembly was placed in a 250 ℃ furnace (under inert gas) for 60 minutes of heat treatment, the wafer assembly was removed and immediately immersed in water at ambient temperature (25 ℃) for 10 minutes (the ambient temperature water used was significantly in excess), the wafer assembly was removed from the water and wiped dry. This was repeated until blistering of the silver layer (i.e. signs of peeling) was observed and the number of cycles was recorded.

The raised structure of the composite layer of the contact piece assembly can pass the thermal shock test for 500 times, and the silver layer is not abnormal when observed by a magnifying glass.

As shown in the attached drawings, the protector of the invention comprises an insulating base 3, a movable contact piece assembly 4, a static contact piece assembly 5, a PTC placing groove 31, a PTC heating element 6, a temperature sensing element 7 and a cover plate 8, wherein only the movable contact piece assembly 4 adopts the contact piece assembly in the embodiment, namely, the contact piece 1 (high-conductivity copper sheet) in the movable contact piece assembly 4 is the movable contact piece, the contact 2 (silver-nickel alloy) is the movable contact, the static contact piece assembly 5 comprises a static contact piece 51 and a static contact 52,

the static contact piece 51 is a bending structure and is fixedly connected with the insulating base 3 (integrally injection-molded with the insulating base 3), the bending structure sequentially comprises a first edge, a second edge and a third edge from left to right, one end of the first edge along the length direction (left-right direction) is connected with one end of the third edge along the length direction (left-right direction) through the second edge, the first edge is positioned at the bottom of the insulating base 3,

the PTC placing groove 31 is arranged on the insulating seat 3 and is positioned above the static contact piece 51, the groove bottom of the PTC placing groove 31 is communicated with the upper piece surface of the static contact piece 51, the PTC heating element 6 is placed in the PTC placing groove 31 in a matching way, the piece surface of the static contact piece 51 positioned in the first edge area is provided with a supporting point 511 which is convex upwards, the supporting point 511 upwards supports the PTC heating element 6 in a propping way, so that the PTC heating element 6 is better contacted with the static contact piece 51,

the temperature sensing element 7 is arranged above the PTC heating element 6, the temperature sensing element 7 is larger than the PTC heating element 6 and the PTC placing groove 31 in the left-right direction, the moving contact piece is arranged above the temperature sensing element 7, the moving contact piece protrudes downwards along the length direction (left-right direction) of the moving contact piece to form a moving contact, two downward protruding points which are arranged and distributed along the length direction (left-right direction) of the moving contact piece are arranged on the surface of the moving contact piece far away from the moving contact piece, the first contact point 41 and the second contact point 42 are respectively a first contact point 41 and a second contact point 42, the first contact point 41 and the second contact point 42 are smaller than the moving contact in volume, the first contact point 41 and the second contact point 42 are respectively abutted against the upper part of the temperature sensing element 7 or disconnected, and the temperature sensing element 7 is supported and controlled to be abutted against and separated from the,

a movable connection point 43 is arranged on the movable contact piece between the first contact point 41 and the second contact point 42 along the length direction (left and right direction) of the movable contact piece, when the circuit is over-current and/or over-temperature, the temperature sensing element 7 is deformed, so that the second section of the movable contact piece is lifted, the movable contact and the fixed contact 52 are disconnected, the circuit is opened, and the function of protecting the circuit is achieved,

the cover plate 8 is arranged above the movable contact piece, the cover plate 8 comprises a supporting piece 81, the supporting piece 81 is fixed at the lower part of the cover plate 8 (the supporting piece 81 and the cover plate 8 are integrally molded by injection), two downward convex points are arranged on the surface of the supporting piece 81, the two downward convex points are respectively a first point 811 and a second point 812, the first point 811 is abutted against the first section of the movable contact piece, the second point 812 is abutted against or disconnected from the second section of the movable contact piece, the convex degree of the first point 811 is greater than that of the second point 812, which provides a movable space for the second section of the movable contact piece,

the periphery of the cover plate 8 is provided with a tiny convex welding point for ultrasonic welding, the insulating seat 3 is of a boat-shaped structure, the cover plate 8 is matched with the insulating seat 3 to form a closed space through ultrasonic welding,

the cover plate 8 is positioned with the movable contact piece through the positioning pin and the movable contact piece is clamped in the positioning groove of the cover plate 8.

The end of the static contact piece 51 penetrating the insulating base 3 is connected with an external conductor, and the end of the movable contact piece penetrating the insulating base 3 is also connected with an external conductor (not shown in the figure), so that a conductive loop is formed among the movable contact piece, the movable contact, the static contact 52 and the static contact piece 51.

The temperature sensing element 7 is placed in the PTC placing groove 31, the temperature sensing element 5 is longer than the PTC heating element 6 and the PTC placing groove 31 in the left-right direction, when the circuit has over-current due to fault, the temperature of the PTC heating element 6 rises due to the increase of heating power, when the temperature exceeds the preset temperature, the resistance can be increased sharply instantly, the current in the loop is reduced to a safe value rapidly, meanwhile, as the PTC heating element 6 heats and transfers heat to the temperature sensing element 7, when the temperature reaches the set temperature of the temperature sensing element 7, the temperature sensing element 7 deforms, so that the movable contact is jacked to open the circuit, and the over-temperature protection and the over-current protection can be achieved at the same time;

when the circuit is powered off, the temperature drops, the temperature sensing element 7 restores the state before deformation, and the movable contact piece drops, so that the movable contact and the fixed contact 52 restore to the normally closed circuit state.

The protector of example 1 passed the test for detecting the electric life of DC 9V-25 a 10000 times, and the contact portion between the silver contact layer and the contact piece was free from abnormality after the test.

Detection of a control sample:

directly carrying out a thermal shock test (the test operation is the same as that in example 1) on the contact piece assembly (the composite part is of a plane structure, and is shown in the attached drawing 1) which is subjected to warm rolling and compounding but is not subjected to top punching treatment in example 1, and observing the phenomenon that a silver layer foams after the thermal shock test is carried out for 441 times, namely the sign that the silver layer falls off; meanwhile, when the contact piece assembly which is not subjected to top punching treatment is actually used in a protector, the opening and closing actions after electrification are in a planar contact mode, and the contact piece assembly is easy to ignite and burn out.