An on-board inverter controller based on SIC power module

Abstract

The present invention belongs to the technical field of inverter controllers, and discloses a vehicle-mounted inverter controller based on a SIC power module, including a controller body, a mounting groove is provided on the top of the controller body, a plurality of evenly distributed mounting heat dissipation components are provided on the bottom of the controller body, each of the mounting heat dissipation components is plugged with a mounting component, a packaging component is installed on the top of the controller body, and two left and right anti-slip strips are installed on the bottom of the controller body; the mounting heat dissipation component includes a positioning hole provided at the bottom of the inner cavity of the mounting groove, and a connecting groove located at the bottom of the positioning hole is provided inside the controller body. The present invention can separate each heat-generating component in the mounting groove by installing the heat dissipation component and the mounting component, and prevent the heat dissipated from interfering with each other through the heat insulation cloth, which not only effectively controls the flow of heat, but also greatly reduces the damage of heat to other components.

Description

Technical Field

[0001] The invention belongs to the technical field of inverter controllers, in particular to a vehicle-mounted inverter controller based on a SIC power module. Background Art

[0002] With the rapid development and popularization of new energy vehicles, the technology of the electric vehicle industry has achieved unprecedented development. Among the electric vehicle drive controllers, the inverter controller is a key component for realizing AC / DC energy conversion, and is used for functions such as motor driving, energy recovery during braking, and providing AC power. This results in the inverter controller needing to operate efficiently when the electric vehicle is driving. Since there are many circuits and components distributed inside it, heat will be generated during operation. Although the inverter controller used in the prior art has a built-in heat dissipation mechanism, due to the small size of the inverter controller and the complex internal components, the space available for gas circulation is extremely limited. The unreasonable spatial distribution of many components will cause the hot air flow to move randomly in the inverter, increase the flow time, and slow down the heat dissipation efficiency. Summary of the invention

[0003] 1. Technical issues to be resolved

[0004] In order to solve the problems raised in the above background technology, the present invention provides a vehicle-mounted inverter controller based on a SIC power module, which has the advantage of good heat dissipation effect.

[0005] By installing the heat dissipation component and the mounting component together, each heat-generating component in the mounting slot can be separated, and the heat dissipated by them will not interfere with each other through the heat insulation cloth, which not only effectively controls the flow of heat, but also greatly reduces the damage of heat to other low-temperature components.

[0006] (II) Technical solution

[0007] To achieve the above object, the present invention provides the following technical solutions: an on-vehicle inverter controller based on a SIC power module, comprising a controller body, a mounting groove is provided on the top of the controller body, a plurality of evenly distributed mounting heat dissipation components are provided on the bottom of the controller body, each of the mounting heat dissipation components is plugged with a mounting component, a packaging component is installed on the top of the controller body, and two left and right anti-slip strips are installed on the bottom of the controller body;

[0008] The heat dissipation installation assembly includes a positioning hole opened at the bottom of the inner cavity of the installation groove, a connecting groove located at the bottom of the positioning hole is opened inside the controller body, a rotating groove located at the bottom of the connecting groove is opened at the bottom of the controller body, a locking groove is opened at the top of the inner cavity of the rotating groove, and the installation groove is communicated with the outside of the controller body through the positioning hole, the connecting groove and the rotating groove;

[0009] The mounting assembly includes a mounting rod inserted into the positioning hole, the upper end of the mounting rod extends into the interior of the mounting groove and abuts against the packaging assembly, the side of the mounting rod is fixedly connected to a plurality of fixed plug-in strips located inside the mounting groove and evenly distributed, the outer side of the fixed plug-in strip is plugged with a movable plug-in strip, and the outer side of the movable plug-in strip is fixedly connected to a heat insulation cloth;

[0010] The packaging assembly includes a cover arranged on the top of the controller body, a sealing gasket is installed on the top of the inner cavity of the cover, the bottom of the sealing gasket is tightly fitted with the controller body and the top of the mounting assembly, the interior of the cover is a cavity, and a plurality of evenly distributed air inlet holes are opened inside the sealing gasket, and the upper and lower ends of the air inlet holes are respectively connected to the cavity or the mounting groove, and the cavity is connected to the heat dissipation fan inside the mounting groove through a hose;

[0011] The top of the heat insulation cloth is in contact with the sealing pad, the bottom of the heat insulation cloth is provided with heat insulation cotton, the bottom of the heat insulation cotton is in contact with the bottom of the inner cavity of the installation groove, and both ends of the heat insulation cloth are fixedly connected with a movable plug-in strip, and the movable plug-in strip is plugged into the inside of the fixed plug-in strip;

[0012] The interior of a plurality of heat dissipation components in the installation slot is plugged with installation components, and the interior space of the installation slot is divided into a plurality of temperature-independent areas by the installation components and the heat insulation cloth.

[0013] Preferably, the positioning hole is a polygonal groove, the rotating groove is a circular groove, the connecting groove and the retaining groove are both elliptical grooves, the connecting groove and the retaining groove have the same size, and the long axes of the connecting groove and the retaining groove are perpendicular to each other.

[0014] Preferably, the mounting rod includes a mounting rod body inserted into the positioning hole, a sliding cavity is provided at the top of the mounting rod body, a connecting groove is provided at the bottom of the mounting rod body, a limiting groove located in the middle section of the connecting groove is provided inside the mounting rod body, a positioning groove is provided at the bottom of the inner cavity of the limiting groove, a clamping groove is provided at the bottom of the inner cavity of the positioning groove, an anti-slip groove is provided inside the mounting rod body and is located outside the positioning groove, and two limiting blocks are fixedly installed inside the anti-slip groove.

[0015] Preferably, the arc length of the outer surface of the limit block is five degrees, and the arc line between the opposite ends of the outer surface arcs of the two limit blocks is ninety-five degrees.

[0016] Preferably, a pressing block is movably installed inside the sliding cavity, a connecting rod is inserted into the inside of the connecting groove, the upper end of the connecting rod passes through the connecting groove and extends to the inside of the sliding cavity and is fixedly connected to the pressing block, the lower end of the connecting rod passes through the connecting groove and extends to the bottom of the mounting rod body and is fixedly connected with a stopping block, and the stopping block is movably engaged with the inside of the stopping groove.

[0017] Preferably, the outside of the connecting rod is fixedly sleeved with a spring stopper movably sleeved inside the limiting groove, the outer surface of the packaging assembly is provided with a sliding groove located at the bottom of the spring stopper, and the outside of the connecting rod is slidably clamped with a spring pressure block located below the spring stopper and movably installed inside the positioning groove through the sliding groove.

[0018] Preferably, a return spring located between the spring stop block and the spring pressure block is provided on the outside of the connecting rod, and the side of the spring pressure block is fixedly connected to a positioning block movably installed inside the anti-slip groove, the arc length of the positioning block is five degrees, and the two sides of the positioning block are respectively in contact with two limit blocks.

[0019] (III) Beneficial effects

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. The present invention can separate each heat-generating component in the installation slot by installing the heat dissipation component and the installation component, and prevent the heat dissipated from interfering with each other through the heat insulation cloth, which not only effectively controls the flow of heat, but also greatly reduces the damage of heat to other components.

[0022] 2. The present invention not only facilitates the workers to connect the installation components by installing the heat dissipation components, but also the installation heat dissipation components that are later enclosed in each independent area and without the installation components inserted can also be used as heat dissipation holes, which not only helps daily heat dissipation, but more importantly, can effectively prevent the entry of dust.

[0023] 3. The present invention can assist the thermal insulation cloth in limiting the hot air flow in each independent area by connecting the thermal insulation cotton to the bottom of the thermal insulation cloth, and can also facilitate compacting the connection lines between the components at the bottom of the inner cavity of the installation groove, thereby facilitating wiring while effectively avoiding the flow of hot air flow in adjacent independent areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the structure of the present invention;

[0025] Figure 2 It is an internal schematic diagram of the present invention;

[0026] Figure 3 This is a bottom schematic diagram of the present invention after the package assembly is opened;

[0027] Figure 4 It is a cross-sectional view of the front side of the rotating groove of the present invention;

[0028] Figure 5 for Figure 4 A local enlarged schematic diagram of the middle A;

[0029] Figure 6 It is a structural schematic diagram of the installation components in the present invention;

[0030] Figure 7 It is a disassembly schematic diagram of the installation components in the present invention;

[0031] Figure 8 for Figure 7 A partial schematic diagram of the middle spring pressure block;

[0032] Fig. 9 It is a front cross-sectional view of the mounting rod body of the present invention.

[0033] In the figure: 1. controller body; 2. mounting slot; 3. heat dissipation assembly installation; 31. positioning hole; 32. connecting slot; 33. rotating slot; 34. locking slot; 4. mounting assembly; 41. mounting rod; 411. mounting rod body; 412. sliding cavity; 413. connecting slot; 414. limiting slot; 415. positioning slot; 416. locking slot; 417. anti-slip slot; 418. limiting block; 42. fixed plug strip; 43. movable plug strip; 44. pressing block; 45. connecting rod; 46. locking block; 47. spring stopper; 48. spring pressure block; 49. positioning block; 410. sliding slot; 5. packaging assembly; 51. cover; 52. sealing gasket; 53. air inlet; 6. anti-slip strip; 7. reset spring. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] like Figures 1 to 9 As shown, the present invention provides a vehicle-mounted inverter controller based on a SIC power module, comprising a controller body 1, a mounting groove 2 is provided on the top of the controller body 1, a plurality of evenly distributed mounting heat dissipation components 3 are provided on the bottom of the controller body 1, each of the mounting heat dissipation components 3 is plugged with a mounting component 4, a packaging component 5 is installed on the top of the controller body 1, and two left and right anti-slip strips 6 are installed on the bottom of the controller body 1;

[0036] The heat dissipation assembly 3 includes a positioning hole 31 provided at the bottom of the inner cavity of the mounting groove 2, a connecting groove 32 provided at the bottom of the positioning hole 31 inside the controller body 1, a rotating groove 33 provided at the bottom of the connecting groove 32 at the bottom of the controller body 1, and a locking groove 34 provided at the top of the inner cavity of the rotating groove 33. The mounting groove 2 is communicated with the outside of the controller body 1 through the positioning hole 31, the connecting groove 32 and the rotating groove 33; by installing the heat dissipation assembly 3, it is not only convenient for the staff to connect the mounting assembly 4, but also the heat dissipation assembly 3 which is enclosed in each independent area and has no mounting assembly 4 inserted therein can also be used as a heat dissipation hole, which is not only helpful for daily heat dissipation, but more importantly, it can effectively prevent the entry of dust;

[0037] The mounting assembly 4 includes a mounting rod 41 inserted into the positioning hole 31, the upper end of the mounting rod 41 extends to the inside of the mounting groove 2 and abuts against the packaging assembly 5, and the side of the mounting rod 41 is fixedly connected to a plurality of fixed plug-in strips 42 located inside the mounting groove 2 and evenly distributed, and the outer side of the fixed plug-in strip 42 is plugged with a movable plug-in strip 43, and the outer side of the movable plug-in strip 43 is fixedly connected with a heat insulation cloth;

[0038] The packaging component 5 includes a cover 51 arranged on the top of the controller body 1, a sealing gasket 52 is installed on the top of the inner cavity of the cover 51, the bottom of the sealing gasket 52 is tightly fitted with the top of the controller body 1 and the mounting component 4, the interior of the cover 51 is a cavity, and a number of evenly distributed air inlet holes 53 are opened inside the sealing gasket 52, and the upper and lower ends of the air inlet holes 53 are respectively connected to the cavity or the mounting slot 2, and the cavity is connected to the heat dissipation fan inside the mounting slot 2 through a hose; the air inlet holes 53 can facilitate the staff to install the temperature control valve or the sealing plug, ensuring that the heat dissipation fan in the mounting slot 2 can blow the cold air in a directional manner to each independent area with excessive temperature, so as to achieve accurate and effective heat dissipation and cooling treatment;

[0039] The top of the heat-insulating cloth is in contact with the sealing pad 52, and the bottom of the heat-insulating cloth is provided with heat-insulating cotton, and the bottom of the heat-insulating cotton is in contact with the bottom of the inner cavity of the installation slot 2. Both ends of the heat-insulating cloth are fixedly connected with a movable plug-in strip 43, and the movable plug-in strip 43 is plugged into the inside of the fixed plug-in strip 42; the heat-insulating cotton connected to the bottom of the heat-insulating cloth can not only assist the heat-insulating cloth to limit the hot air flow in each independent area, but also facilitate the number of connection lines between the components to be compacted at the bottom of the inner cavity of the installation slot 2, which is convenient for wiring and effectively avoids the flow of hot air flow in adjacent independent areas;

[0040] Several heat dissipation components 3 in the installation slot 2 are plugged with installation components 4, and the internal space of the installation slot 2 is divided into several temperature-independent areas by the installation components 4 and the heat insulation cloth; by cooperating with the heat dissipation components 3 and the installation components 4, each heat-generating component in the installation slot 2 can be separated, and the heat dissipated by them will not interfere with each other through the heat insulation cloth, which not only effectively controls the flow of heat, but also greatly reduces the damage of heat to other components.

[0041] like Figure 5 As shown, the positioning hole 31 is a polygonal groove, the rotating groove 33 is a circular groove, the connecting groove 32 and the locking groove 34 are both elliptical grooves, the connecting groove 32 and the locking groove 34 have the same size, and the long axes of the connecting groove 32 and the locking groove 34 are perpendicular to each other; the positioning hole 31 can limit the movement of the installation component 4, and then the heat insulation cloth connected together by the fixed plug strip 42 and the movable plug strip 43 can be more stable, and at the same time, the fixed plug strip 42 and the movable plug strip 43 arranged on the outside of the installation rod body 411 can ensure that the heat insulation cloth between two adjacent installation components 4 will not directly pass through the top of the installation heat dissipation component 3, thereby avoiding the situation where the two adjacent independent area spaces are not completely independent.

[0042] like Figure 6 As shown, the mounting rod 41 includes a mounting rod body 411 inserted into the positioning hole 31, a sliding cavity 412 is provided at the top of the mounting rod body 411, a connecting groove 413 is provided at the bottom of the mounting rod body 411, a limiting groove 414 located in the middle section of the connecting groove 413 is provided inside the mounting rod body 411, a positioning groove 415 is provided at the bottom of the inner cavity of the limiting groove 414, a clamping groove 416 is provided at the bottom of the inner cavity of the positioning groove 415, an anti-slip groove 417 located on the outer side of the positioning groove 415 is provided inside the mounting rod body 411, and two limiting blocks 418 are fixedly installed inside the anti-slip groove 417; the movement of the spring pressure block 48 can be restricted by the anti-slip groove 417, thereby ensuring that the mounting rod 41 as a whole will not be completely separated from the connecting rod 45 as a whole, thereby ensuring that the positioning block 49 can accurately contact the limiting block 418.

[0043] like Fig. 9 As shown, the arc length of the outer surface of the limit block 418 is five degrees, and the arc line between the opposite ends of the outer surface arcs of the two limit blocks 418 is ninety-five degrees; the movement of the positioning block 49 can be restricted by the two limit blocks 418, and then with the cooperation of the slide groove 410 and the spring pressure block 48, it is ensured that the pressing block 44 as a whole can only reciprocate within a range of 90 degrees, thereby ensuring that the long axis of the locking block 46 is always parallel or perpendicular to the long axis of the locking groove 34.

[0044] like Fig. 9As shown, a pressing block 44 is movably installed inside the sliding cavity 412, a connecting rod 45 is inserted into the inside of the connecting groove 413, the upper end of the connecting rod 45 passes through the connecting groove 413 and extends to the inside of the sliding cavity 412 and is fixedly connected to the pressing block 44, the lower end of the connecting rod 45 passes through the connecting groove 413 and extends to the bottom of the mounting rod body 411 and is fixedly connected to a stopping block 46, and the stopping block 46 is movably engaged with the inside of the stopping groove 34.

[0045] like Figure 8 and Fig. 9 As shown, the outside of the connecting rod 45 is fixedly sleeved with a spring stopper 47 which is movably sleeved inside the limiting groove 414, and the outer surface of the packaging component 5 is provided with a slide groove 410 located at the bottom of the spring stopper 47, and the outside of the connecting rod 45 is slidably clamped with a spring pressure block 48 which is located below the spring stopper 47 and movably installed inside the positioning groove 415 through the slide groove 410.

[0046] like Figure 8 As shown, a return spring 7 located between a spring stop block 47 and a spring pressure block 48 is arranged on the outside of the connecting rod 45, and a positioning block 49 movably installed inside the anti-slip groove 417 is fixedly connected to the side of the spring pressure block 48, and the arc length of the positioning block 49 is five degrees, and the two sides of the positioning block 49 are respectively in contact with two limit blocks 418.

[0047] The working principle and use process of the present invention:

[0048] First, assemble all the required parts in the inverter controller, then plan the required divided areas according to the layout of all the parts, and enclose each area by a number of mounting components 4 and heat insulation cloth, that is, insert the lower end of the mounting rod body 411 into the interior of the positioning hole 31 through the mounting component 4, and then press the pressing block 44 to first compress the reset spring 7 under the restriction of the positioning groove 415 and the spring pressure block 48, and at the same time, the stop block 46 can be pressed into the interior of the rotating groove 33 through the connecting rod 45, and then the pressing block 44 is rotated and the stop block 46 is driven to rotate through the connecting rod 45, so that the stop block 46 can be rotated to the bottom of the stop block 46 under the restriction of the limit block 418 on the positioning block 49, and then the pressing block 44 is released, and the stop block 46 can be lifted to the interior of the stop groove 34 through the connecting rod 45 under the elastic force of the reset spring 7;

[0049] After all the installation components 4 at the four corners of each independent area are installed in the above manner, each area can be sealed by means of fixed plug strips 42 and movable plug strips 43. Then, according to the position of the independent area below, a temperature control valve is installed inside one of the air inlet holes 53 corresponding to the top of each independent area, and the interiors of the remaining air inlet holes 53 corresponding to the top of each independent area can be sealed. When the temperature of one or more areas is too high, the corresponding temperature control valve will be automatically opened, and the cooling fan will be started at the same time, so that cold air enters the corresponding independent area through the air inlet holes 53 and the temperature control valve, and the original hot air flow is discharged through several installed heat dissipation components 3 at the bottom of the independent area.

[0050] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0051] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A vehicle-mounted inverter controller based on a SIC power module, comprising a controller body (1), characterized in that: The top of the controller body (1) is provided with a mounting groove (2), the bottom of the controller body (1) is provided with a plurality of evenly distributed mounting heat dissipation components (3), each of the mounting heat dissipation components (3) is plugged with a mounting component (4), the top of the controller body (1) is provided with a packaging component (5), and the bottom of the controller body (1) is provided with two left and right anti-slip strips (6); The heat dissipation assembly (3) comprises a positioning hole (31) formed at the bottom of the inner cavity of the mounting groove (2); a connecting groove (32) formed inside the controller body (1) and located at the bottom of the positioning hole (31); a rotating groove (33) formed at the bottom of the connecting groove (32) is formed at the bottom of the controller body (1); a locking groove (34) is formed at the top of the inner cavity of the rotating groove (33); and the mounting groove (2) is in communication with the outside of the controller body (1) via the positioning hole (31), the connecting groove (32) and the rotating groove (33); The mounting assembly (4) comprises a mounting rod (41) inserted into the positioning hole (31), the upper end of the mounting rod (41) extending into the interior of the mounting groove (2) and abutting against the packaging assembly (5), the side of the mounting rod (41) being fixedly connected to a plurality of fixed plug-in strips (42) located inside the mounting groove (2) and evenly distributed, the outer side of the fixed plug-in strip (42) being plugged with a movable plug-in strip (43), and the outer side of the movable plug-in strip (43) being fixedly connected to a heat insulation cloth; The packaging component (5) comprises a cover (51) arranged on the top of the controller body (1), a sealing gasket (52) is installed on the top of the inner cavity of the cover (51), the bottom of the sealing gasket (52) is tightly fitted with the controller body (1) and the top of the mounting component (4), the interior of the cover (51) is a cavity, and the interior of the sealing gasket (52) is provided with a plurality of evenly distributed air inlet holes (53), the upper and lower ends of the air inlet holes (53) are respectively connected to the cavity or the mounting groove (2), and the cavity is connected to the internal heat dissipation fan of the mounting groove (2) through a hose; The top of the heat insulation cloth is in contact with the sealing pad (52), the bottom of the heat insulation cloth is provided with heat insulation cotton, the bottom of the heat insulation cotton is in contact with the bottom of the inner cavity of the installation groove (2), and both ends of the heat insulation cloth are fixedly connected to a movable plug-in strip (43), and the movable plug-in strip (43) is plugged into the interior of the fixed plug-in strip (42); The interior of the plurality of heat dissipation installation components (3) in the installation slot (2) is plugged with an installation component (4), and the interior space of the installation slot (2) is divided into a plurality of temperature-independent areas by the installation component (4) and the heat insulation cloth.

2. According to claim 1, a vehicle-mounted inverter controller based on a SIC power module is characterized in that: The positioning hole (31) is a polygonal groove, the rotating groove (33) is a circular groove, the connecting groove (32) and the locking groove (34) are both elliptical grooves, the connecting groove (32) and the locking groove (34) have the same size, and the long axes of the connecting groove (32) and the locking groove (34) are perpendicular to each other.

3. The vehicle-mounted inverter controller based on the SIC power module according to claim 1, characterized in that: The mounting rod (41) comprises a mounting rod body (411) inserted into the positioning hole (31); a sliding cavity (412) is provided at the top of the mounting rod body (411); a connecting groove (413) is provided at the bottom of the mounting rod body (411); a limiting groove (414) located in the middle section of the connecting groove (413) is provided inside the mounting rod body (411); a positioning groove (415) is provided at the bottom of the inner cavity of the limiting groove (414); a clamping groove (416) is provided at the bottom of the inner cavity of the positioning groove (415); an anti-slip groove (417) is provided inside the mounting rod body (411) and located outside the positioning groove (415); two limiting blocks (418) are fixedly installed inside the anti-slip groove (417).

4. The vehicle-mounted inverter controller based on the SIC power module according to claim 3 is characterized in that: The arc length of the outer surface of the limiting block (418) is five degrees, and the arc line between the opposite ends of the outer surface arcs of the two limiting blocks (418) is ninety-five degrees.

5. The vehicle-mounted inverter controller based on the SIC power module according to claim 3 is characterized in that: A pressing block (44) is movably installed inside the sliding cavity (412), a connecting rod (45) is inserted into the inside of the connecting groove (413), the upper end of the connecting rod (45) passes through the connecting groove (413) and extends to the inside of the sliding cavity (412) and is fixedly connected to the pressing block (44), the lower end of the connecting rod (45) passes through the connecting groove (413) and extends to the bottom of the mounting rod body (411) and is fixedly connected to a locking block (46), and the locking block (46) is movably locked in the inside of the locking groove (34).

6. The vehicle-mounted inverter controller based on the SIC power module according to claim 5, characterized in that: The outside of the connecting rod (45) is fixedly sleeved with a spring stopper (47) which is movably sleeved inside the limiting groove (414); the outer surface of the packaging component (5) is provided with a sliding groove (410) located at the bottom of the spring stopper (47); the outside of the connecting rod (45) is slidably engaged with a spring pressure block (48) located below the spring stopper (47) and movably installed inside the positioning groove (415) through the sliding groove (410).

7. The vehicle-mounted inverter controller based on the SIC power module according to claim 6 is characterized in that: The connecting rod (45) is provided with a return spring (7) located between a spring stopper (47) and a spring pressure block (48) on the outside, and a positioning block (49) movably mounted inside the anti-slip groove (417) is fixedly connected to the side of the spring pressure block (48), the positioning block (49) having an arc length of five degrees, and two sides of the positioning block (49) are respectively in contact with two limit blocks (418).

Images