Creep-resistant injection molding gear, EMB locking mechanism with creep-resistant injection molding gear and vehicle

Abstract

The utility model discloses an injection molding gear with creep resistance, a locking groove or locking teeth are arranged on the injection molding gear, the injection molding gear is manufactured by adopting an injection molding process, an inner framework is arranged in the injection molding gear, and the inner framework is made of a metal material. According to the injection molding gear, the inner framework made of the metal material is arranged in the gear, so that the creep resistance of the locking gear can be effectively improved. The utility model further discloses an EMB locking mechanism and a vehicle.

Description

Technical Field

[0001] The utility model belongs to the technical field of brake systems, and in particular relates to an injection-molded gear with anti-creep function and an EMB locking mechanism and a vehicle having the same. Background Art

[0002] Existing electromechanical brake systems (EMB) all have a locking mechanism, one of which has a structure that uses an electromagnet as a locking power device, and locks and unlocks the power transmission by extending and retracting the electromagnet locking head, thereby achieving the locking of the entire parking system, wherein the locking groove or tooth that matches the electromagnet locking head is integrated on the gear, that is, when the parking lock is applied, due to the presence of the parking clamping force, the contact surface between the gear and the locking head will be subjected to a large force and maintained for a long time as the vehicle is parked.

[0003] The EMB locking mechanism includes a locking gear matched with an electromagnet, and the locking gear is a double gear. The problems of the double gear in the prior art are:

[0004] There is a locking groove on the duplex gear. If the duplex gear is made of metal material, there is no problem with the strength of the duplex gear, but there is a problem of meshing noise between metal gears and impact noise when locking; if the duplex gear is made of plastic material, the noise problem can be solved, but there is a risk of plastic deformation of creep. This is because when the parking lock is engaged, due to the existence of the parking clamping force, there is a reverse force on the transmission route, and this reverse force will act on the locking mechanism module through the locking head structure of the electromagnet and the push rod. Similarly, there will be a long-term force between the locking head and the locking end face in the locking groove on the duplex gear. The duplex gear is made of plastic gear. Since the holding force acts on the plastic material for a long time, the duplex gear will creep, which will cause plastic deformation of the duplex gear. Utility Model Content

[0005] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model provides an injection molded gear, the purpose of which is to improve the anti-creep performance.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is: an injection molded gear with anti-creep, a locking groove or a locking tooth is set on the injection molded gear, the injection molded gear is made by injection molding process and an inner skeleton is set in the injection molded gear, and the inner skeleton is made of metal material.

[0007] The injection molded gear is a double gear, which includes a large gear and a small gear. The locking groove or locking tooth is arranged on the large gear, and the inner frame is arranged in the large gear.

[0008] The pinion gear and the inner frame are integrally formed.

[0009] The pinion and the inner frame are assembled and formed.

[0010] The pinion gear and the inner frame are connected by interference fit or spline connection.

[0011] The inner skeleton includes an inner ring and a support bar connected to the inner ring and inserted into the inside of the large gear. A plurality of support bars are provided and all the support bars are evenly distributed along the circumferential direction. The inner ring is connected to the small gear.

[0012] The inner skeleton also includes an outer ring connected to the support bar and located inside the large gear, and the diameter of the outer ring is greater than the diameter of the inner ring.

[0013] The two ends of the support bar are respectively connected to the outer ring and the inner ring, and the outer ring and the inner ring are coaxially arranged.

[0014] The locking grooves are arranged in plurality and all the locking grooves are evenly distributed along the circumferential direction on the large gear, and each of the support bars is located between two adjacent locking grooves in the circumferential direction.

[0015] The pinion is made by powder metallurgy process.

[0016] The utility model also provides an EMB locking mechanism, comprising the injection molding gear.

[0017] The utility model also provides a vehicle, comprising the EMB locking mechanism.

[0018] The injection molded gear of the utility model can effectively improve the anti-creep performance of the locking gear by arranging an inner frame made of metal material inside the gear. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] This specification includes the following drawings, which show the following contents:

[0020] Figure 1 It is a front view of the large gear in the first embodiment;

[0021] Figure 2 is a schematic structural diagram of a pinion in Embodiment 1;

[0022] Figure 3 is a schematic diagram of the structure of the inner skeleton in Example 1;

[0023] Figure 4 is a schematic structural diagram of the large gear in the first embodiment;

[0024] Figure 5 is a schematic diagram of the assembly of the inner frame and the pinion gear in the second embodiment;

[0025] Figure 6 is a schematic diagram of the assembly of the inner frame and the pinion gear in the third embodiment;

[0026] Figure 7 is a schematic diagram of the structure of the large gear in the third embodiment;

[0027] Figure 8 It is a front view of the large gear in the third embodiment;

[0028] Fig. 9 is an exploded schematic diagram of the locking mechanism;

[0029] Fig.10 It is an overall view of the lock head and gear status when parking;

[0030] Fig.11 This is the front view of the lock head and gear status when parking;

[0031] Fig.12 It is the MGU cutaway view;

[0032] Fig.13 This is a simplified diagram of the positions of the gears when locked;

[0033] Fig.14 It is a structural schematic diagram of an injection-molded double gear in the prior art;

[0034] Fig.15 It is another structural schematic diagram of the injection-molded double gear of the prior art;

[0035] Fig.16 It is a schematic diagram of the structure of a small gear in an injection-molded double gear in the prior art;

[0036] Fig.17 It is a structural schematic diagram of a large gear in an injection-molded double gear in the prior art;

[0037] Fig.18 It is a front view of a large gear in an injection-molded double gear in the prior art;

[0038] Markings in the figure are: 1. injection molded double gears; 2. double gears I; 2a. large gear; 2b. small gear; 3. double gears II; 3a. large gear; 3b. small gear and skeleton assembly structure; 3b1. inner skeleton; 3b2. small gear; 4. double gears III; 4a. large gear; 4b. small gear and skeleton assembly structure; 4b1. inner skeleton; 4b2. small gear; 5. double gears; 5a. locking end face; 5b. locking groove; 5c. non-locking end face; 6. circuit board; 7. ECU housing; 8. ECU housing cover; 9. shaft pin; 10. electromagnet; 10a. locking head; 11. MGU housing; 11a. cavity; 12. motor; 13. motor gear; 14. output gear. DETAILED DESCRIPTION

[0039] The specific implementation methods of the utility model are further explained in detail below with reference to the accompanying drawings through the description of embodiments, with the aim of helping technicians in the field to have a more complete, accurate and in-depth understanding of the concept and technical solution of the utility model and facilitating its implementation.

[0040] The utility model provides an injection molded gear with creep resistance. A locking groove or a locking tooth is arranged on the injection molded gear. The injection molded gear is made by an injection molding process and an inner frame is arranged inside the injection molded gear. The inner frame is made of metal material.

[0041] The utility model also provides an EMB locking mechanism, including an injection molded gear (also known as a locking gear), a locking groove or a locking tooth is arranged on the locking gear, the locking gear is made by an injection molding process and an inner frame is arranged inside the locking gear, and the inner frame is made of metal material.

[0042] Specifically, the locking gear is a double gear, which includes a large gear and a small gear, a locking groove is set on the large gear, an inner frame is set in the large gear, and the inner frame is made of metal material. By setting the inner frame of metal material in the large gear, the creep resistance of the double gear can be effectively improved.

[0043] like Fig.13 As shown, the electromagnet is used as the power device of the EMB locking mechanism. The electromagnet push rod extends and retracts to cooperate with the locking groove set on the large gear 4a of the double gear, thereby locking the entire transmission system. Fig.13 As shown in the simplified diagram, the motor gear 13 is characterized by a high speed and a small torque, while the output gear 14 is characterized by a slow speed and a large torque. Since the motor gear 13 rotates at a relatively high speed, if the large gear 4a of the double gear meshing with it is made of metal, the metal gears will generate noise under high-speed meshing rotation, and the impact of the locking push rod head on the large gear of the double gear when the locking mechanism is locked will also generate noise. Considering the characteristics of the locking mechanism, when parking, the gear teeth of the large gear 4a of the double gear and the motor gear 13 are not subjected to force when locked, and at the same time, they are at a level where the force is relatively small, which is the spoke length along with the parking lock. The large gear 4a of the double gear is subjected to stress for a long time, so the large gear 4a of the double gear can be replaced by plastic material, and the small gear 4b2 of the double gear is made of metal. In this way, the meshing of the plastic gear and the metal gear can solve the noise problem. At the same time, the noise caused by the impact of the locking head on the metal gear when the locking mechanism is locked will also be reduced. However, if the large gear of the double gear is made of plastic gear, the problem is that due to the existence of the parking structure, the spokes of the double gear are subjected to stress for a long time when locked, and the long-term stress will cause the plastic spokes to creep. Therefore, when injection molding the large gear of the double gear, a metal skeleton structure is designed inside to effectively solve the risk of creep.

[0044] like Figures 9 to 12 As shown, the MGU includes an EMB locking mechanism, an MGU housing 11, an ECU housing cover 8, an ECU housing 7, a circuit board 6 and a motor 12. The ECU housing 7 is fixedly arranged on the MGU housing 11, the ECU housing cover 8 is fixedly arranged on the ECU housing 7, and the electromagnet 10 is arranged in the MGU housing 11. The motor gear and the motor 12 are arranged axially, the motor 12 is arranged in a cavity arranged on the MGU housing 11, the double gear 5 is arranged on the shaft pin 9, the shaft pin 9 is press-fitted on the MGU housing 11, the electromagnet 10 is arranged in another cavity 11a arranged on the MGU housing 11, and the circuit board 6 is arranged in the ECU housing 7. The EMB locking mechanism includes an electromagnet 10 and a multi-stage gear transmission mechanism. The locking head of the electromagnet 10 is arranged to be embedded in the locking groove 5b provided on the locking gear of the multi-stage gear transmission mechanism in the locked state. The locking head of the electromagnet 10 extends and retracts to cooperate and unlock with the locking groove 5b on the locking gear, so as to realize the parking locking function of the entire EMB brake.

[0045] like Fig.10 and Fig.11 As shown, a locking end face 5a and a non-locking end face 5c are arranged in the locking groove 5b, and the locking end face 5a and the non-locking end face 5c are inner wall faces at opposite ends in the length direction of the locking groove 5b, and the locking end face 5a is used to contact with the surface of the locking head in the locked state, and the non-locking end face 5c is used to push the locking head out of the locking groove 5b during the rotation of the duplex gear 5, and the non-locking end face 5c is a plane inclined in the locking groove 5b, and an angle is formed between the non-locking end face 5c and the axis of the duplex gear 5, and the moving direction of the locking head is parallel to the axis of the duplex gear 5, and a first contact face in contact with the non-locking end face 5c is arranged on the locking head, and the first contact face is an inclined plane, and an angle is formed between the first contact face and the moving direction of the locking head, and the angle is an acute angle, and the inclination angle of the first contact face is the same as that of the non-locking end face 5c. The locking end face 5a is a plane parallel to the axis of the duplex gear 5. The locking head is provided with a second contact surface in contact with the locking end face 5a. The second contact surface is a plane parallel to the moving direction of the locking head. In the locked state, the second contact surface fits the locking end face 5a. The locking head plays a circumferential limit role on the duplex gear 5 to achieve locking. A plurality of locking grooves 5b are provided, and all locking grooves 5b are evenly distributed along the circumference on the gear with the axis of the duplex gear 5 as the center line. In the locked state, the locking head is inserted into one of the locking grooves 5b.

[0046] like Fig.13As shown, the multi-stage gear transmission mechanism includes a first-stage transmission mechanism and a second-stage transmission mechanism, the driving gear of the first-stage transmission mechanism is connected to the motor 12, the motor 12 provides driving force, the driven gear (i.e., the large gear 4a) of the first-stage transmission mechanism is provided with a locking groove 5b, and the driving gear (i.e., the motor gear 13) of the first-stage transmission mechanism is meshed with the driven gear. The driven gear of the first-stage transmission mechanism is fixedly connected with the driving gear (i.e., the small gear 4b2) of the second-stage transmission mechanism to form a double gear 5, and the driven gear of the second-stage transmission mechanism is the output gear 14, the driven gear of the first-stage transmission mechanism is meshed with the driving gear of the second-stage transmission mechanism, and the output gear 14 outputs power.

[0047] When the parking lock is engaged, the ECU (electronic control unit) transmits the locking command to the electromagnet 10 through the busbar, the electromagnet 10 is energized, the push rod and the moving iron core of the electromagnet 10 extend, and the locking head 10a extends into the locking groove 5b of the gear for parking lock, as shown in the figure. Fig.11 As shown, the locking head 10a cooperates with the locking end face 5a to limit the rotation of the duplex gear 5 used for parking lock, thereby realizing the locking function; when the parking is released, the ECU transmits the release command to the electromagnet 10 through the busbar, the electromagnet 10 is energized in the reverse direction, the locking head 10a of the electromagnet 10 retreats, and the locking head 10a retreats outside the locking groove 5b. The locking head 10a of the electromagnet 10 is decoupled from the locking groove 5b of the duplex gear 5, and the rotation of the duplex gear 5 is not restricted by the locking head 10a, thereby realizing the release of the parking lock.

[0048] like Fig.11 As shown, when parking, the locking head of the electromagnet contacts the locking end face 5a. Due to the parking clamping force, the double gear 5 tends to rotate clockwise, so that the gear has a holding force on the locking head in the clockwise direction, and the holding force is maintained during parking. If the gear structure is entirely injection molded, the gear will have the risk of creeping and plastic deformation under long-term force maintenance. However, if a metal inner frame is designed in the injection molded gear structure, the parking holding force will act on the large frame. The supporting effect of the large metal frame can effectively eliminate the risk of gear creep.

[0049] Embodiment 1

[0050] In this embodiment, if Figures 1 to 4As shown, the diameter of the large gear 3a is larger than the diameter of the small gear 3b2. The material of the large gear 3a is plastic. The large gear 3a adopts the coating process, and the small gear 3b2 adopts the powder metallurgy process. The spokes of the large gear 3a are provided with locking grooves. The coating process is injection molding on the inner skeleton 3b1. The distance of the inner skeleton 3b1 in the circumferential direction of the gear exceeds the distance of the locking groove in the circumferential direction of the gear, ensuring that the locking groove can act on the inner skeleton 3b1 under the maintenance of long-term parking force. The inner skeleton 3b1 is made of a material with high strength such as metal, and can meet the requirements of the injection molding process.

[0051] In this embodiment, if Figures 1 to 4 As shown, the material of the inner skeleton 3b1 is metal, the inner skeleton 3b1 is formed by a stamping process, the material of the pinion 3b2 is powder metallurgy, and the pinion 3b2 and the inner skeleton 3b1 are assembled together to form a pinion and skeleton assembly structure 3b.

[0052] like Figure 1 and Figure 3 As shown, the inner skeleton 3b1 includes an inner ring and a support bar connected to the inner ring and inserted into the large gear 3a. The inner ring is a circular ring structure and the inner ring and the large gear 3a are coaxially arranged. The inner ring is located at the center of the large gear 3a. A plurality of support bars are provided and all support bars are evenly distributed along the circumferential direction with the axis of the inner ring as the center line. The inner ring is fixedly connected to the pinion 3b2 and the two are coaxial. A plurality of locking grooves are provided and all locking grooves are evenly distributed along the circumferential direction on the large gear 3a. Each support bar is located between two adjacent locking grooves in the circumferential direction.

[0053] In this embodiment, eight locking grooves are provided on the large gear 3a, and eight support bars are also provided. All support bars are radially distributed inside the large gear 3a, which can effectively improve the anti-creep performance of the duplex gear.

[0054] The double gears of this embodiment have the following advantages:

[0055] 1. Reduce noise: The plastic gear structure can reduce weight and reduce gear transmission noise;

[0056] 2. Can reduce the impact sound: the locking groove is integrally injection molded, and the impact sound with the electromagnet locking head is reduced;

[0057] 3. Can increase the spoke strength: The large frame is made of metal, which can effectively increase the anti-creep performance of injection molded gears.

[0058] Embodiment 2

[0059] In this embodiment, if Figure 5As shown, the materials of the pinion 3b2 and the inner skeleton 3b1 are both powder metallurgy, and the pinion 3b2 and the inner skeleton 3b1 are integrally formed using the powder metallurgy process. The molding process here is not unique. Then, injection molding is performed on the basis of the pinion and skeleton assembly structure 3b formed by the pinion 3b2 and the inner skeleton 3b1 to form a large gear, and finally a creep-resistant double gear is formed.

[0060] Embodiment 3

[0061] The difference between this embodiment and the first and second embodiments is mainly that the structure of the inner frame is different. In this embodiment, Figure 6 and Figure 8 As shown, the inner skeleton 4b1 also includes an outer ring connected to the support bar and located inside the large gear 4a. The outer ring is a circular ring structure, and the diameter of the outer ring is greater than the diameter of the inner ring. The two ends of the support bar in the length direction are fixedly connected to the outer ring and the inner ring respectively, and the outer ring and the inner ring are coaxially arranged. The outer ring is added, on the one hand, to increase the strength of the inner skeleton, because the outer ring is added, the support effect can be increased. If there is no outer ring, the inner skeleton is equivalent to a cantilever structure when subjected to force, so that the long support bar is easy to deform when subjected to force. On the other hand, the outer ring part is close to the outer gear position of the double gear large gear. The gear is an injection molding process. After injection molding, the tooth shape will produce asymmetric shrinkage deformation because the locking groove is close to one side. Therefore, the inner skeleton with an outer ring is set, so that the tooth shape of the large gear can produce uniform shrinkage deformation after injection molding. Such a design can make the injection molding tooth shape better.

[0062] The above is an exemplary description of the utility model in conjunction with the accompanying drawings. Obviously, the specific implementation of the utility model is not limited to the above-mentioned method. As long as various non-substantial improvements are made using the method concept and technical solution of the utility model; or the above concept and technical solution of the utility model are directly applied to other occasions without improvement, they are all within the protection scope of the utility model.

Claims

1. An injection molded gear with anti-creep function, wherein a locking groove or a locking tooth is provided on the injection molded gear, and the characteristics are: The injection molded gear is made by injection molding process and an inner frame is arranged inside the injection molded gear, and the inner frame is made of metal material; The injection molded gear is a double gear, which includes a large gear and a small gear. The locking groove or locking tooth is arranged on the large gear, and the inner frame is arranged in the large gear.

2. The injection molded gear according to claim 1, characterized in that: The pinion gear and the inner frame are integrally formed.

3. The injection molded gear according to claim 1, characterized in that: The pinion and the inner frame are assembled and formed.

4. The injection molded gear according to claim 1, characterized in that: The pinion gear and the inner frame are connected by interference fit or spline connection.

5. The injection molded gear according to any one of claims 1 to 4, characterized in that: The inner skeleton includes an inner ring and a support bar connected to the inner ring and inserted into the inside of the large gear. A plurality of support bars are provided and all the support bars are evenly distributed along the circumferential direction. The inner ring is connected to the small gear.

6. The injection molded gear according to claim 5, characterized in that: The inner skeleton also includes an outer ring connected to the support bar and located inside the large gear, and the diameter of the outer ring is greater than the diameter of the inner ring.

7. The injection molded gear according to claim 6, characterized in that: The two ends of the support bar are respectively connected to the outer ring and the inner ring, and the outer ring and the inner ring are coaxially arranged.

8. The injection molded gear according to claim 5, characterized in that: The locking grooves are arranged in plurality, and all the locking grooves are evenly distributed along the circumferential direction on the large gear, and each of the support bars is located between two adjacent locking grooves in the circumferential direction.

9. The injection molded gear according to any one of claims 1 to 4, characterized in that: The pinion is made by powder metallurgy process. 10.EMB locking mechanism, characterized by: Including the injection molded gear described in any one of claims 1 to 9.

11. A vehicle, characterized in that: Includes the EMB locking mechanism as claimed in claim 10.

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