AMT speed measurement system

Abstract

The utility model provides an AMT speed measuring system which is used for solving the problem of sensor pulse signal drift caused by bearing cover installation errors and the technical problem of high processing difficulty caused by processing parameters such as rotor tooth groove depth and precision requirements in the prior art. According to the utility model, the rotating speed sensor is directly and fixedly mounted on the gearbox housing through the first mounting hole, and the odometer sensor is directly mounted on the gearbox housing through the second mounting hole, so that the problem of pulse signal drift caused by mounting errors is reduced. And for a vehicle which does not need an odometer sensor, a bolt can be directly mounted in the second mounting hole, so that the flexibility of product application is improved. The inner ring formed by the large teeth of the speed measuring rotor is not provided with a rotor tooth groove, so that the problem of high processing difficulty caused by processing parameters such as the depth of the rotor tooth groove and error requirements is solved, the weight of the speed measuring rotor is reduced, and the lightweight design requirements of a gearbox and a whole vehicle are met.

Description

Technical Field

[0001] The utility model relates to a transmission speed measuring system, in particular to an AMT speed measuring system. Background Art

[0002] The tachometer rotor is mounted on the output shaft of the transmission and can rotate synchronously with the output shaft. When the tachometer rotor rotates, the odometer sensor can measure its speed and transmit the measured speed to the vehicle instrument. The number of teeth on the tachometer rotor varies depending on the measurement accuracy and specifications of the odometer sensor.

[0003] AMT (Automatic Mechanical Transmission) has been rapidly promoted in the domestic commercial vehicle field in recent years. AMT determines the timing of gear shifting based on the speed difference and has high requirements for speed accuracy. Therefore, it is necessary to add an output shaft speed measuring rotor to the output shaft to transmit the output shaft speed signal to the AMT controller to calculate the gear shifting timing.

[0004] As the configuration of AMT models becomes higher and higher, the instrumentation of some vehicles can calculate the vehicle speed based on the output shaft speed CAN signal sent by the transmission, thus eliminating the need for a traditional odometer sensor. This can not only meet the requirements for vehicle speed calculation, but also save an odometer sensor and reduce costs. However, some vehicle instruments do not have this function; or they are exported to different countries and regions, and the regulations are different, requiring AMT to be equipped with an odometer sensor.

[0005] Chinese patent CN216696371U discloses a transmission speed measuring system, including an output speed measuring gear, which is assembled on the second shaft of the transmission through a bearing. This patent application can realize the simultaneous acquisition of the output shaft speed sensor and the odometer sensor signals, but its disadvantage is that the output shaft speed sensor and the odometer sensor are installed on the bearing cover, and the bearing cover installation error will cause the sensor pulse signal drift problem. In addition, the tooth structure that receives the odometer pulse signal has rotor tooth grooves, and it is necessary to consider the high processing difficulty caused by the processing parameters and precision requirements such as the rotor tooth groove depth. Utility Model Content

[0006] The utility model aims to solve the technical problems of sensor pulse signal drift caused by bearing cover installation error in the prior art and high processing difficulty caused by processing parameters and precision requirements such as rotor tooth groove depth, and proposes an AMT speed measurement system.

[0007] In order to solve the above technical problems, the technical solutions provided by the utility model are as follows:

[0008] An AMT speed measuring system, which is special in that it includes a gearbox housing, an output shaft, a bearing, a speed measuring rotor, an output flange, an odometer sensor and a speed sensor installed in the gearbox housing;

[0009] The bearing, the speed measuring rotor and the output flange are sequentially sleeved on the output shaft, and the output flange is located at the rear end of the output shaft; the front end of the speed measuring rotor abuts against the bearing, and the rear end is connected to the output flange; the speed measuring rotor is sleeved on the output shaft in an interference fit manner and rotates synchronously with the output shaft;

[0010] The gearbox housing is provided with a first mounting hole and a second mounting hole. The speed sensor is installed in the first mounting hole. The speed sensor is used to collect and measure pulses at the front end of the speed measuring rotor and maintain a gap with the outer side of the front end. The odometer sensor or bolt is installed in the second mounting hole. The odometer sensor is used to collect and measure pulses at the rear end of the speed measuring rotor and maintain a gap with the outer side of the rear end.

[0011] Furthermore, the tachometer rotor includes small teeth and large teeth. The small teeth are located at the front end of the tachometer rotor and are used to measure the rotational speed of the output shaft. The large teeth are located at the rear end of the tachometer rotor and are used to measure the rotational speed of the vehicle odometer. The output flange is connected to the inner ring formed by the large teeth.

[0012] Furthermore, the number of the large teeth is smaller than the number of the small teeth, and a rotor slot root is provided in the inner ring formed by the small teeth, and the rotor slot root abuts against the bearing.

[0013] Furthermore, the first mounting hole is located at the upper end of the shell, the second mounting hole is located at the lower end of the shell, and the central axes of the first mounting hole and the second mounting hole are staggered.

[0014] Furthermore, the bearing is assembled on the output shaft by interference fit.

[0015] Beneficial effects of the utility model:

[0016] 1. The utility model directly fixes the speed sensor on the gearbox housing through the first mounting hole, thereby reducing the pulse signal drift problem caused by installation errors.

[0017] 2. The utility model provides a second mounting hole on the transmission housing. For vehicles that require an odometer sensor, the odometer sensor can be directly mounted on the transmission housing through the second mounting hole, thereby also avoiding the problem of pulse signal drift caused by installation errors. For vehicles that do not require an odometer sensor, bolts can be directly installed in the second mounting hole, thereby improving the flexibility of product application.

[0018] 3. In the utility model, the inner circle formed by the large teeth of the speed measuring rotor is not provided with a rotor slot root. By designing a slot-free structure, not only the processing difficulty and processing cost are reduced, but also the weight of the speed measuring rotor is reduced while meeting all functions and assembly process consistency, thereby meeting the lightweight design requirements of the gearbox and the entire vehicle.

[0019] 4. In the present invention, the speed measuring rotor combines the functions of measuring the odometer speed and measuring the output shaft speed, thereby improving the integration level. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the main structure of an AMT speed measurement system embodiment of the utility model (the gearbox housing is omitted);

[0021] Figure 2 This is a cross-sectional structural diagram of an embodiment of an AMT speed measurement system of the utility model;

[0022] Figure 3 It is a schematic diagram of the three-dimensional structure of a speed measuring rotor in an embodiment of an AMT speed measuring system of the utility model;

[0023] Figure 4 for Figure 1 Right view of .

[0024] Description of reference numerals:

[0025] 1- output shaft; 2- bearing; 3- odometer sensor; 4- speed rotor; 5- output flange; 6- gearbox housing; 7- speed sensor. DETAILED DESCRIPTION

[0026] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0027] The utility model proposes an AMT speed measurement system, see Figure 1 , Figure 2 , including a gearbox housing 6, and an output shaft 1, a bearing 2, a speed measuring rotor 4, an output flange 5 and a speed sensor 7 arranged inside the gearbox housing 6.

[0028] The bearing 2, the speed measuring rotor 4 and the output flange 5 are sequentially sleeved on the output shaft 1. The bearing 2 is assembled on the output shaft 1 with an interference fit. The speed measuring rotor 4 is sleeved on the transmission output shaft 1 with an interference fit and rotates synchronously with the output shaft 1. The output flange 5 is located at the rear end of the output shaft 1 and can limit the speed measuring rotor 4.

[0029] like Figure 3As shown, the speed rotor 4 includes small teeth and large teeth. The small teeth are located at the front end of the speed rotor 4 and are used to measure the speed of the output shaft 1. The bearing 2 plays a positioning role for the speed rotor 4. The large teeth are located at the rear end of the speed rotor 4. The output flange 5 is connected to the inner ring formed by the large teeth and is used to measure the speed of the vehicle odometer. The speed rotor 4 is designed to be integrated. One speed rotor 4 can achieve two speed measurement purposes, reducing the number of parts.

[0030] The speed measuring rotor 4 is processed in one piece, and the number of large teeth is smaller than the number of small teeth. The small teeth with more teeth at the front end can meet the measurement accuracy requirements of the speed sensor 7 on the output shaft 1, and the large teeth with fewer teeth at the rear end can meet the measurement accuracy requirements of the odometer sensor 3. The inner circle formed by the small teeth is provided with a rotor slot root. The inner circle formed by the large teeth is not provided with a slot root. By designing a slot-free structure, not only the processing difficulty and processing cost are reduced, but also the weight of the speed measuring rotor 4 is reduced while meeting all functions and assembly processes, meeting the lightweight design requirements of the gearbox and the whole vehicle.

[0031] like Figure 4 As shown, the gearbox housing 6 is provided with a first mounting hole and a second mounting hole, the first mounting hole is located at the upper end of the housing, and the second mounting hole is located at the lower end of the housing, and the central axes of the first mounting hole and the second mounting hole are staggered in the radial and axial directions of the output shaft 1, which is convenient for assembly. The speed sensor 7 is installed in the first mounting hole, and the speed sensor 7 is used to collect the pulses of the small teeth of the speed rotor 4 and maintain a gap with the outer side of the small teeth. According to the actual needs of the vehicle, the odometer sensor 3 can be installed in the second mounting hole to collect and measure the pulses of the large teeth of the speed rotor 4; a gap is maintained between the odometer sensor 3 and the outer side of the large teeth of the speed rotor 4. For vehicles that do not require the traditional odometer sensor 3, bolts can be directly installed in the second mounting hole, which improves the flexibility of system application. The speed sensor 7 and the odometer sensor 3 on the output shaft 1 are directly fixed to the gearbox housing 6 through the first mounting hole and the second mounting hole, and the installation position is more reliable.

[0032] Installation process: first, install the speed rotor 4 on the output shaft 1 in an interference fit manner, with the front end of the speed rotor 4 abutting the bearing 2 for positioning, and the rear end relying on the output flange 5 for fixing and limiting; assemble the output flange 5 at the end of the output shaft 1; assemble the speed sensor 7 in the first mounting hole on the gearbox housing 6, with the speed sensor 7 facing the front end of the speed rotor 4 and maintaining a certain gap with the outer side of the small tooth; assemble the odometer sensor 3 in the second mounting hole on the gearbox housing 6, with the odometer sensor 3 facing the rear end of the speed rotor 4 and maintaining a certain gap with the outer side of the large tooth.

Claims

1. An AMT speed measurement system, characterized in that: It comprises a gearbox housing (6), an output shaft (1), a bearing (2), a speed measuring rotor (4), an output flange (5), an odometer sensor (3) and a speed sensor (7) installed in the gearbox housing (6); The bearing (2), the speed measuring rotor (4) and the output flange (5) are sleeved on the output shaft (1) in sequence, and the output flange (5) is located at the rear end of the output shaft (1); the front end of the speed measuring rotor (4) is in contact with the bearing (2), and the rear end is connected to the output flange (5); the speed measuring rotor (4) is sleeved on the output shaft (1) in an interference fit manner, and rotates synchronously with the output shaft (1); The gearbox housing (6) is provided with a first mounting hole and a second mounting hole. The speed sensor (7) is mounted in the first mounting hole. The speed sensor (7) is used to collect pulses at the front end of the speed measuring rotor (4) and maintain a gap with the outer side of the front end. The odometer sensor (3) or the bolt is mounted in the second mounting hole. The odometer sensor (3) is used to collect pulses at the rear end of the speed measuring rotor (4) and maintain a gap with the outer side of the rear end.

2. The AMT speed measurement system according to claim 1, characterized in that: The speed measuring rotor (4) comprises small teeth and large teeth, wherein the small teeth are located at the front end of the speed measuring rotor (4) and are used to measure the rotation speed of the output shaft (1); the large teeth are located at the rear end of the speed measuring rotor (4) and are used to measure the rotation speed of the vehicle odometer, and the output flange (5) is connected to the inner ring formed by the large teeth.

3. The AMT speed measurement system according to claim 2, characterized in that: The number of the large teeth is smaller than the number of the small teeth, and a rotor slot root is provided in the inner ring formed by the small teeth, and the rotor slot root abuts against the bearing (2).

4. The AMT speed measurement system according to claim 3, characterized in that: The first mounting hole is located at the upper end of the shell, the second mounting hole is located at the lower end of the shell, and the central axes of the first mounting hole and the second mounting hole are staggered.

5. The AMT speed measurement system according to claim 4, characterized in that: The bearing (2) is assembled on the output shaft (1) by interference fit.

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