Drill bits are cutting tools used to remove material to create holes, almost always of circular cross-section. Drill bits come in many sizes and shapes and can create different kinds of holes in many different materials. In order to create holes drill bits are usually attached to a drill, which powers them to cut through the workpiece, typically by rotation. The drill will grasp the upper end of a bit called the shank in the chuck. Drill Bits,Drill Bit Set,Drill Bit Types,Diamond Drill Bit Shenyang Lubang Railway Maintenance Machinery Co.,Ltd. , https://www.srmfrailwayequip.com
Nanjing Jiaotong Vocational and Technical College (211118) Wen Aimin electronic control system is divided into 4T45-E is a fully automatic front-wheel drive electronically controlled automatic transmission, providing 4 forward gear and reverse gear including overspeed; automatic transmission control module The shift point is controlled by two shift solenoid valves; the vane pump provides the oil line pressure, and the automatic transmission control module uses the pressure control solenoid valve to adjust the main line pressure. The pressure plate of the hydraulic torque converter is not fully locked on the torque converter cover. On the contrary, the pressure plate maintains a slight slip in the 2nd, 3rd and 4th gears (about 20r/min). The specific purpose of the electronically controlled capacity clutch is to reduce noise and vibration caused by the torque converter clutch engagement.
The composition and characteristics of the 14T45-E automatic transmission electronic control system 4T45-E automatic transmission electronic control system components are: 2 shift solenoid valves, 1 hydraulic torque converter clutch control pulse width modulation solenoid valve, 1 automatic Transmission pressure control (PC) solenoid valve, 1 automatic transmission oil temperature sensor, 1 input speed sensor, 1 output speed sensor, 1 automatic transmission oil pressure manual valve position switch assembly, 1 automatic transmission harness assembly , 1 parking gear / neutral position switch.
The main components of the electronic control system and their installation locations are shown. The characteristics of the electronic control system mainly include the following two points.
The machine adopts a pipeline pressure control system, which can continuously adjust the system pipeline pressure, thereby compensating for the normal wear of the clutch fiber sheets, seals, springs and other parts. The automatic transmission control module monitors the input speed sensor and the output speed sensor during command shifting to determine if the shift is too fast or too slow. The automatic transmission control module can maintain the setting by adjusting the signal from the automatic transmission pressure control solenoid valve. The shift feel. When the automatic transmission is overhauled or replaced, the adaptive function of the automatic transmission must be set again. Use TECH 2 to select the following menu to set the adaptive function of the automatic transmission: ScanTool - SpecialFunctions - TransmissionOutputControls - ResetTransmissionAdapts.
Automatic transmission indicator and information. When the automatic transmission control module determines that the life of the automatic transmission oil is less than 10%, the automatic transmission oil indicator is turned on; once the automatic transmission control module determines that the life of the automatic transmission oil is greater than 10%, the replacement of the automatic transmission oil indicator is extinguished. When the automatic transmission control module detects that the automatic transmission oil temperature is not lower than 132 for 1 min, the message "TransHotIdleEngine" is displayed.
4T45-E automatic transmission electronic control system components and features and functions of the torque converter clutch control pulse width modulation solenoid valve. The solenoid valve is a normally closed pulse width modulated solenoid valve for controlling the engagement and disengagement of the torque converter clutch. The automatic transmission control module controls the engagement/separation ratio of the torque converter clutch using a negative duty cycle and operating the solenoid valve at a fixed frequency of 42 Hz. The solenoid valve can smoothly or reduce the engagement and disengagement pressure of the torque converter clutch, thereby achieving smooth operation of the torque converter clutch. If the automatic transmission control module receives a high voltage signal from the brake switch indicating that the brake pedal has been depressed, the automatic transmission control module immediately disengages the torque converter clutch. The solenoid torque of the torque converter clutch should be 10fi~lln at 20t and about 16n at 150t. The automatic transmission pressure control solenoid valve. The solenoid valve is a precision electronic pressure regulator for controlling the pressure of the automatic transmission line to control the amount of current through the valve coil. When the current increases, the magnetic field generated by the coil moves the movable core of the solenoid valve away from the oil drain hole. After the oil drain hole is opened, the output oil pressure regulated by the pressure control solenoid valve is lowered, thereby reducing the pipeline pressure. The automatic transmission control module controls the automatic transmission pressure control solenoid valve based on various input signals including throttle position, oil temperature, intake manifold absolute pressure, and gear state. The automatic transmission control module utilizes a positive duty cycle and controls the pressure control solenoid valve at a frequency of 614 Hz. The higher the duty cycle, the greater the current flowing through the solenoid valve. The operation of the pressure control solenoid valve is controlled by the high pressure (positive) side of the pressure control solenoid circuit on the automatic transmission control module.
The automatic transmission control module provides a ground path for the circuit and monitors the average current and continuously changes the pressure control solenoid valve duty cycle to maintain the control current of the pressure control solenoid valve at an appropriate value (Table 1). The resistance of the pressure control solenoid valve coil is 30~5 at 20T. Table 1 The relationship between the duty ratio of the pressure control solenoid valve and the control current and the line pressure. The duty ratio, % current, A line E force maximum and minimum shift solenoid valve . The shift solenoid valve is used to control the upshift and downshift operations on all forward gear positions. The shift solenoid valves are normally open. These shift solenoid valves work together in a combined sequence of on and off to control the position of the 1-2, 2-3 and 3-4 shift valve groups. The automatic transmission control module determines the appropriate solenoid valve state combination and automatic transmission gear position (Table 2) based on the vehicle's operating conditions. The automatic transmission control module energizes the valve by providing grounding for the shift solenoid valve circuit, and a current flows through the coil of the solenoid valve to generate a magnetic field, repels the movable iron core in the electromagnetic valve, and fixes the one-way ball of the electromagnetic valve to the oil supply port to prevent The automatic transmission oil is discharged through the solenoid valve, so that the automatic transmission oil pressure at the end of the shift valve is increased, and the upshift operation is initiated by the action of the shift valve. The resistance of the shift solenoid valve is 190~24 at 201:24n~31ft at 88T: When the voltage is higher than 7.5V, the shift solenoid should act. When the voltage is lower than 1V, the shift solenoid should return.
Gear position 1-2 gear solenoid valve 2-3 gear solenoid valve parking gear, reverse gear, neutral gear on and off 1 gear on and off 2 gear disconnected 3 裆 disconnected 4 gears on automatic transmission oil pressure manual Valve position switch assembly. The automatic transmission oil pressure manual valve position switch assembly is connected to the control valve body. The assembly contains three automatic transmission oil pressure switches and an automatic transmission oil temperature sensor with control circuitry as shown. Automatic car maintenance and repair 2006 aiming off the speed of the oil power off the self-changer pressure signal speed 汕 force off 4 self-variable pressure flap drive transmission control module (TCM) (49 black) transmission oil pressure switch has 2 The (DR switch and REV switch) are normally open and are used to indicate the position of the manual valve. The automatic transmission control module uses this information to control line pressure, engagement and disengagement of the torque converter clutch (TCC), and operation of the shift solenoid valve. The TCC release switch confirms whether the torque converter clutch has been disengaged when the automatic transmission control module commands the torque converter clutch to disengage. The switch is normally closed. Depending on whether there is transmission oil pressure on the switch, each automatic transmission oil pressure switch is either disconnected to the circuit of the automatic transmission control module or to the ground circuit of the automatic transmission module. The automatic transmission control module measures the signal voltage of each terminal to ground of the automatic transmission oil pressure manual valve position switch and compares this voltage with the automatic transmission oil pressure manual valve position switch combination table stored in the automatic transmission control module memory. If the automatic transmission control module does not recognize the switch timing, it will cause a fault code to be set; if the automatic transmission oil pressure manual valve position switch timing indicates that the selected gear position conflicts with other sensor input signals of the automatic transmission control module, The fault code will be set.
(5) Output speed sensor. The automatic transmission output speed sensor is a magnetic pulse sensor that uses the vehicle speed information to control the timing of shifting, line pressure, and clutching and disengagement of the clutch maintenance and repair service. The output speed sensor is mounted on the housing of the speed sensor rotor on the card to the differential, and an air gap of 0.27 mm to 1.57 mm is left between the sensor and the rotor teeth. The output speed sensor has a resistance of 1500fl1650 at 20 ft. (6) input speed sensor. The automatic transmission input speed sensor is a magnetic pulse sensor that is used by the automatic transmission control module to control line pressure, engagement and disengagement of the torque converter clutch, and automatic transmission shifting. This information is also used to calculate the gear ratio of the corresponding gear and the slip speed of the torque converter clutch. The input speed sensor is mounted on the automatic transmission housing, below the oil circuit board, near the drive sprocket. An air gap of 0.26 mm to 2.90 is reserved between the input speed sensor and the drive sprocket teeth. The resistance of the input speed sensor is 625 725 (7) automatic transmission oil temperature sensor at 201. The automatic transmission oil temperature sensor is a negative temperature coefficient thermistor located in the automatic transmission oil pressure manual valve position switch assembly (the assembly is bolted to the control valve body). The automatic transmission control module controls the line pressure, the timing of the shift, and the engagement of the torque converter clutch based on the signal of the automatic transmission oil temperature sensor. When the automatic transmission oil temperature reaches 140, the automatic transmission control module enters the hot mode. Above this temperature, the automatic transmission control module will modify the automatic transmission shift timing and the torque converter clutch engagement, attempting to reduce the automatic transmission. The heat generated reduces the temperature of the automatic transmission oil. In the hot mode, the automatic transmission control module keeps the torque converter clutch engaged in the 3rd and 4th gears. In addition, the automatic transmission control module also performs the 2-3 and 3-4 shifts in advance to Reduce the heat generation of the automatic transmission oil.
(8) Automatic transmission gear position switch. The automatic transmission position switch includes four internal switches that indicate the position of the automatic transmission shift lever. The automatic transmission control module provides a supply voltage to each of the switching circuits. By grounding one or more of the switching circuits, the automatic transmission control module can detect the selected gear position based on a change in state of the switch input signal. The switch input signal to the automatic transmission control module is "HI (high)" and "LOW" on the troubleshooter.
To represent. HI represents the power supply voltage signal and LOW represents the zero voltage signal.
Drill bits come in standard sizes, described in the drill bit sizes article. A comprehensive drill bit and tap size chart lists metric and imperial sized drill bits alongside the required screw tap sizes. There are also certain specialized drill bits that can create holes with a non-circular cross-section.