Clamping device used during hub polishing

Abstract

The invention provides a clamping device for polishing a hub, which comprises a base (1), a mechanical arm (2) is movably connected to the base (1), and a rotary clamping device (3) correspondingly matched with the hub is connected to one end of the mechanical arm (2). The hub polishing device is simple in structure and convenient to use, the mechanical arm is low in operation energy consumption and stable in operation, the stability of a hub during polishing is effectively guaranteed, the polishing efficiency of the hub is effectively improved, and the competitive product rate is increased.

Description

Technical Field

[0001] The invention relates to the field of processing automobile parts, in particular to a clamping device for grinding a wheel hub. Background Art

[0002] The automobile wheel hub is a cylindrical metal component installed on the axle to support the automobile tire. It is an important driving component of the automobile, responsible for bearing the weight of the automobile body, transmitting power and braking force, and ensuring the stability of the vehicle.

[0003] According to the different manufacturing processes and materials, automobile wheels are mainly divided into steel wheels and aluminum alloy wheels. Compared with steel wheels, aluminum alloy wheels have the advantages of light weight, high hardness, excellent heat dissipation and beautiful appearance. In terms of manufacturing process, steel wheels mainly include rolling, stamping and welding processes; alloy wheels are mostly aluminum alloy wheels, mainly including casting, spinning and forging.

[0004] For aluminum alloy wheels that are mainly produced by casting and forging, there are a large number of scratches and burrs, which seriously affect the quality and appearance of the car wheels. At the same time, subsequent processes such as surface paint also have higher requirements on the wheel surface, which requires the wheel to be polished and ground.

[0005] Wheel hubs are generally symmetrical parts with complex structures such as spokes, which limits the grinding and polishing process of machine tools. In the production process of wheel hubs, manual grinding and polishing are mostly used, which takes a long time, the quality of wheel hub polishing varies from person to person, and a large amount of dust is generated during the grinding process, which endangers the health of workers.

[0006] Therefore, polishing with industrial hydraulic robots has become a development trend. During the wheel hub rotation grinding process, the hydraulically driven wheel hub clamping end working device may not be aligned with the wheel hub center, resulting in eccentric torque and causing instability caused by robot vibration. Summary of the invention

[0007] The present invention aims to overcome the deficiencies in the prior art and provide a clamping device for grinding a wheel hub.

[0008] This application provides the following technical solutions: A clamping device for grinding a wheel hub, comprising a base, a mounting seat movably connected to the base, a mechanical arm movably connected to the mounting seat, characterized in that: a rotating clamping device corresponding to the wheel hub is passed through one end of the mechanical arm, the rotating clamping device comprises a shell, a core shaft is arranged in the shell, one end of the core shaft is connected to a motor, and the other end is connected to a bracket, a pair of slide rails are arranged on the bracket, a slider is arranged at each end of the slide rails, a connecting rod is bridged between the two sliders on the same side, a pair of claws corresponding to the wheel hub are connected to each connecting rod, and a pair of claws corresponding to the wheel hub are connected to each connecting rod. A connecting seat is provided on each of the two connecting seats, a two-way oil cylinder is distributed between the two connecting seats, one end of the two piston rods of the two-way oil cylinder are respectively connected to the corresponding connecting seats, the two piston rods are symmetrically distributed on both sides of the core shaft axis, the piston rods have the same telescopic stroke, a first oil circuit and a pair of second oil circuits are provided on the core shaft, a first oil pipe connected and matched with the first oil circuit and two second oil pipes connected and correspondingly connected with the second oil circuit are provided on the two-way oil cylinder, an oil circuit interface corresponding to the first oil circuit and the pair of second oil circuits is provided on the shell, and a hydraulic pump station corresponding to the oil circuit interface is provided in the mounting seat.

[0009] On the basis of the above technical solutions, there are also the following further technical solutions: The piston rod comprises a rod body, one end of which is sleeved with a piston corresponding to the inner wall of the oil cylinder body, and the other end of the rod body extends out of the oil cylinder and is connected to a connecting seat.

[0010] The mechanical arm includes: a first main arm is hinged on a mounting seat, and a base is also provided on the mounting seat to form a corresponding rotary hydraulic reducer; a second main arm and a connecting plate are hinged at one end of the first main arm through an articulated shaft, a first auxiliary arm is hinged between the connecting plate and the mounting seat, a second auxiliary arm is also hinged on the connecting plate, and a rotating clamping device mounting frame connected to a rotating clamping device is hinged at one end of the second auxiliary arm and the second main arm; a swing rod is also hinged on the mounting seat, a second main arm retaining rod is hinged on the swing rod, one end of the second main arm retaining rod is hinged to the second main arm, and a second main arm driven retaining rod is also provided between the mounting seat and the connecting plate, and the swing rod forms a power control match with the first main arm and the hydraulic pump station.

[0011] A spring is sleeved on the rod body of each piston rod, one end of the spring contacts the end of the oil cylinder, and the other end contacts the piston.

[0012] One end of the rod body of each piston rod extends to the other side of the piston to form a limiting section, and the limiting sections of the two piston rods have the same length and are coaxially distributed horizontally.

[0013] The core shaft forms a transmission match with the motor through a coupling.

[0014] The second oil pipe is located at both ends of the bidirectional oil cylinder, and the first oil pipe is located in the middle of the bidirectional oil cylinder, and the axis thereof is colinear with the axis of the core shaft.

[0015] The hydraulic pump station comprises a first main arm driving hydraulic motor corresponding to the first main arm and a second main arm driving hydraulic motor corresponding to the swing arm.

[0016] A power hydraulic system is arranged in the hydraulic pump station, which includes a load-sensitive pump. The hydraulic control circuit of the rotary hydraulic motor, the hydraulic control circuit of the rotary hydraulic reducer, the hydraulic control circuit of the first main arm driving hydraulic motor and the hydraulic control circuit of the second main arm driving hydraulic motor are connected in parallel on the output pipeline of the load-sensitive pump. A load-sensitive multi-way valve is arranged in each hydraulic control circuit. A balancing valve is also arranged in the hydraulic control circuit of the first main arm driving hydraulic motor and the hydraulic control circuit of the second main arm driving hydraulic motor. A brake cylinder is also arranged in the hydraulic control circuit of the rotary hydraulic reducer. An accumulator is also arranged in the hydraulic pump station, and the accumulator is connected in parallel with the hydraulic control circuit of the first main arm driving hydraulic motor, the hydraulic control circuit of the second main arm driving hydraulic motor through pipelines.

[0017] Advantages of the invention: The invention has a simple structure and is easy to use. The mechanical arm has low energy consumption and stable operation, which effectively ensures the stability of the wheel hub during grinding, effectively improves the grinding efficiency of the wheel hub, and increases the rate of fine products. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic structural diagram of the rotary clamping device in the present invention; Figure 3 It is a three-dimensional structural schematic diagram of the rotary clamping device; Figure 4 It is a hydraulic control circuit diagram of the power hydraulic system in the present invention; Figure 5 It is a schematic diagram of the three-dimensional structure of the mechanical arm in the present invention. DETAILED DESCRIPTION

[0019] like Figure 1-5 As shown, a clamping device for grinding a wheel hub comprises a base 1, on which a mounting seat 2a is connected via a rotary hydraulic reducer 2g, so that the mounting seat 2a has a horizontal rotation function.

[0020] The mounting seat 2 a is movably connected to a mechanical arm 2 , and one end of the mechanical arm 2 is connected to a rotating clamping device 3 via a rotating clamping device mounting frame, and the rotating clamping device 3 is clamped with the wheel hub 10 .

[0021] The rotary clamping device 3 comprises a shell 3a connected to the rotary clamping device mounting frame 2h, a core shaft 3b is provided in the shell 3a, a rotary hydraulic motor 3c is installed at the upper end of the shell 3a, and one end of the core shaft 3b forms a power transmission connection with the output shaft of the rotary hydraulic motor 3c through a coupling 7.

[0022] The other end of the core shaft 3b extends out of the housing 3a and is connected to a bracket 3d. A pair of slide rails 3e are provided at the bottom of the bracket 3d, and a corresponding sliding block 3k is provided at both ends of the slide rail 3e.

[0023] A connecting rod 3f is connected between the two sliders on the same side of the slide rail 3e, and a pair of claws 3h corresponding to the wheel hub 10 are connected to the ends of each connecting rod 3f. A connecting seat 3g is connected to the upper surface of each connecting rod 3f.

[0024] A bidirectional oil cylinder 4 is distributed between the two connecting seats 3g. One end of the two piston rods 4a of the bidirectional oil cylinder 4 is respectively connected to the corresponding connecting seats 3g. The two piston rods 4a are symmetrically distributed on both sides of the axis of the core shaft 3b, and the telescopic strokes of the piston rods 4a are the same.

[0025] The piston rod 4a includes a rod body 14a, and a piston 14b is sleeved on one end of the rod body 14a, which corresponds to the inner wall of the oil cylinder body 14d. A spring 6 is sleeved on the rod body 14a of each piston rod 4a, and one end of the spring 6 contacts the end of the oil cylinder, and the other end contacts the piston 14b. One end of the rod body 14a of each piston rod 4a extends to the other side of the piston 14b to form a limiting section. The limiting sections 14c of the two piston rods 4a have the same length and are coaxially distributed horizontally. The other end of the rod body 14a extends out of the oil cylinder and is connected to the connecting seat 3g.

[0026] A first oil circuit 13b and a pair of second oil circuits 113b are provided on the core shaft 3b, and a first oil pipe 4b connected and coordinated with the first oil circuit 13b and two second oil pipes 4c correspondingly connected with the second oil circuits 113b are installed on the two-way oil cylinder 4a. The second oil pipes 4c are located at both ends of the two-way oil cylinder 4, and the first oil pipe 4b is located in the middle of the two-way oil cylinder 4, and its axis is colinear with the axis of the core shaft 3b.

[0027] The housing 1 is provided with an oil circuit interface 5 corresponding to the first oil circuit 13 b and a pair of second oil circuits 113 b , and the base 1 is provided with a hydraulic pump station corresponding to the oil circuit interface 5 and the mechanical arm 2 .

[0028] The robot arm 2 includes a first main arm 2f hinged on a mounting seat 2a, a second main arm 2b and a connecting plate 2c hinged at one end of the first main arm 2f through a hinge axis, a first auxiliary arm 2d hinged between the connecting plate 2c and the mounting seat 2a, a second auxiliary arm 2e also hinged on the connecting plate 2c, and a rotating clamping device mounting frame 2h connected to the rotating clamping device 3 is hinged at one end of the second auxiliary arm 2e and the second main arm 2b.

[0029] A swing rod 2t is also hinged on the mounting seat 2a, a second main arm holding rod 2j is hinged on the swing rod 2t, one end of the second main arm holding rod 2j is hinged to the second main arm 2b, and a second main arm driven holding rod 2k is also provided between the base 1 and the connecting plate 2c, thereby forming a four-bar linkage. The swing rod 2t forms a power control coordination with the first main arm 2f and the hydraulic pump station.

[0030] A power hydraulic system is provided in the hydraulic pump station, which includes a load-sensitive pump 52, on the output pipeline of the load-sensitive pump 52 is installed a load-sensitive regulating device 53, a relief valve 54, and then the pipeline is connected in parallel with the hydraulic control circuit of the rotary hydraulic reducer 2g, the hydraulic control circuit of the first main arm driving hydraulic motor 50, the hydraulic control circuit of the second main arm driving hydraulic motor 51, the hydraulic control circuit of the rotary hydraulic motor 3c and the hydraulic circuit of the accumulator 58. In order to ensure that the rotary hydraulic motor 3 can maintain the current position when not in action, a brake cylinder 69 is provided in the hydraulic control circuit of the rotary hydraulic motor 2g.

[0031] The first solenoid valve 59 and the second solenoid valve 56 are respectively installed in the hydraulic circuits on both sides of the accumulator 58, and a differential pressure reducing valve 57 is also installed in the circuit between the second solenoid valve 56 and the accumulator 58. A controller is set up, and the controller forms a control coordination with the hydraulic control circuit of the first main arm driving hydraulic motor 50, the hydraulic control circuit of the second main arm driving hydraulic motor 51 and the hydraulic circuit of the accumulator 58.

[0032] In each hydraulic control circuit, a pressure compensation valve 68, a load-sensitive multi-way valve 67, a first oil replenishment relief valve 66, a second oil replenishment relief valve 65, a first relief valve 63, a second relief valve 64 and a shuttle valve 60 are provided. A balance valve 61 is also provided in the hydraulic control circuit of the first main arm driving hydraulic motor 50 and the hydraulic control circuit of the second main arm driving hydraulic motor 51. A brake cylinder 69 is also provided in the hydraulic control circuit of the rotary hydraulic reducer 2g. The rotary hydraulic reducer 2g is a purchased component in the prior art, so its structure is not described in detail here.

[0033] One end of the hydraulic circuit of the accumulator 58 is also connected in parallel with the hydraulic control circuits of the first main arm driving hydraulic motor 50 and the second main arm driving hydraulic motor 51 through the parallel shuttle valve 62. The hydraulic shuttle valve 60 in the four hydraulic control circuits selects the maximum load pressure and feeds it back to the load sensing pump 52 to ensure that the pump output flow matches the system demand flow.

[0034] At the same time, in order to further improve the energy utilization efficiency of the system and reduce the heat generation of the system, a potential energy recovery system for the first main arm and the second main arm is specially designed.

[0035] When the first main arm or the second main arm is in the descending condition, the potential energy of the wheel hub and the mechanism itself is released. If the potential energy is not recovered, it will be wasted in the form of heat and increase the temperature rise of the hydraulic system. The potential energy recovery is performed through the accumulator 58, and the parallel shuttle valve 62 is used to ensure that the motor can recover the potential energy when the boom or arm is descending. The controller controls the energy recovery and release.

[0036] During the wheel hub grinding process, the device realizes functions such as grabbing the wheel hub, moving the wheel hub to the grinding cylinder, continuous rotation of the wheel hub, reciprocating motion and wheel hub stacking through hydraulic control.

[0037] Since the first oil pipe 4b is located in the middle of the two-way oil cylinder 4, its axis is collinear with the axis of the core shaft 3b, and the piston rod structure is the same, the wheel hub is clamped and kept in the center under the dual action of the two-way oil cylinder and the spring, that is, its center point is collinear with the axis of the core shaft 3b.

[0038] The rotary hydraulic motor rotates at high speed, driving the wheel hub to rotate at high speed in the grinding cylinder, and the wheel hub is polished under the action of fine sand. Considering that the part of the wheel hub clamped by the clamping jaws 9 and the upper part of the wheel hub may not be fully in contact with the fine sand, the wheel hub should be turned upside down 180° and the wheel hub should be clamped again to repeat the grinding action after completing one grinding.

[0039] When the wheel hub rotates at high speed in the abrasive barrel, there is no slippage between the clamping jaws and the wheel hub, that is, the friction torque provided by the clamping jaws is greater than the friction resistance torque of the abrasive on the wheel hub, that is:

[0040] in M 1 is the friction torque provided by the gripper, M 2 is the friction torque of the abrasive to the wheel hub, μ is the friction coefficient between the jaws and the hub, F is the pressure of the clamping jaws on the hub, R is the wheel hub radius.

[0041] Then, the pressure of the clamping jaws on the wheel hub should satisfy:

[0042] The pressure of the clamping jaws on the wheel hub is provided by the hydraulic pressure and the centering spring. The stiffness of the centering spring can be larger to improve the centering accuracy. The hydraulic pressure is limited by the overflow valve in the hydraulic system and cannot be too high, otherwise it will easily damage the wheel hub.

[0043] When the operator inputs a certain motion signal, the controller controls the load-sensing multi-way valve 67 to further control the forward and reverse rotation of the first main arm driving hydraulic motor, thereby controlling the first main arm to perform corresponding pitching actions.

[0044] In this process, the controller first evaluates the potential of potential energy recovery during the movement. If the potential of potential energy recovery is large, the controller determines whether the state of the accumulator 58 is capable of storing energy. If it is capable of storing energy, the first solenoid valve 59 is opened when the potential energy is released, and high-pressure oil will enter the accumulator 58 for potential energy recovery. Then the controller controls whether the recovery solenoid valve is closed according to the pressure of the accumulator 58. If the accumulator pressure reaches the maximum value, the first solenoid valve 59 is closed in advance. The hydraulic oil stored in the accumulator is controlled by the controller by releasing the second solenoid valve 56 to control whether it is released. The released hydraulic oil returns to the output pipeline of the load-sensing pump 52, and then supplies oil to the actuators in other parallel hydraulic control circuits. When the accumulator releases hydraulic oil, it first passes through the differential pressure reducing valve 57 to ensure that the pressure of the output hydraulic oil is higher than the load pressure by a certain set value. When the accumulator pressure is lower than the pressure of the main circuit, the release of hydraulic oil stops. The oil paths of the oil inlet, oil return, energy storage and energy release circuits of this hydraulic system are as follows (already): Oil inlet: The hydraulic oil enters the load sensing pump 52 from the oil tank and then flows into the 68 pressure compensation valve and then passes through the load sensing multi-way valve 67 to enter the first main arm driving hydraulic motor.

[0045] Oil return line: The hydraulic oil returns to the oil tank from the first main arm driving hydraulic motor through the load-sensing multi-way valve and oil filter.

[0046] Energy storage: The hydraulic oil from the first main arm drives the hydraulic motor through the shuttle valve 62 and the first solenoid valve 59 into the accumulator 58.

[0047] Energy release: The hydraulic oil enters the output pipeline of the load sensing pump 52 from the accumulator 58 through the differential pressure reducing valve 57 , the second solenoid valve 56 and the throttle valve 55 .

[0048] As the pressure of the accumulator 58 is gradually increased as the charging progresses, according to the formula: and It can be seen that the controller can adjust the displacement of the first main arm driving hydraulic motor and the second main arm driving hydraulic motor, as well as the opening degree of the valve body in the hydraulic control circuit of the first main arm driving hydraulic motor 50 and the hydraulic control circuit of the second main arm driving hydraulic motor 51 in real time, adjust the flow rate, and slowly increase the pressure of the energy storage oil circuit while ensuring that the movement of the first main arm and the second main arm meets the requirements, thereby maximizing the recovery of potential energy.

[0049] In addition, the hydraulic control circuit of the first main arm driving hydraulic motor 50, the balancing valve 61 in the hydraulic control circuit of the second main arm driving hydraulic motor 51, and the differential pressure reducing valve for releasing energy can all be replaced by electronic control and controlled in real time by the controller.

[0050] The above mainly describes the basic principles and advantages of the present invention, including but not limited to the above usage.

Claims

1. A clamping device for grinding a wheel hub, comprising a base (1), a mounting seat (2a) movably connected to the base (1), and a mechanical arm (2) movably connected to the mounting seat (2a), characterized in that: A rotary clamping device (3) corresponding to the wheel hub is connected to one end of the mechanical arm (2). The rotary clamping device (3) comprises a housing (3a). A core shaft (3b) is provided in the housing (3a). One end of the core shaft (3b) is connected to a rotary hydraulic motor (3c). The other end of the core shaft (3b) is connected to a bracket (3d). A pair of slide rails (3e) are provided on the bracket (3d). A slider (3k) is provided at each end of the slide rail (3e). A connecting rod (3f) is bridged between two sliders on the same side. A pair of claws (3h) corresponding to the wheel hub are connected to each connecting rod (3f). A connecting seat (3g) is provided on each connecting rod (3f). A bidirectional oil cylinder (4) is distributed between the two connecting seats (3g). The bidirectional oil cylinder (4) One end of the two piston rods (4a) is respectively connected to the corresponding connection seat (3g), the two piston rods (4a) are symmetrically distributed on both sides of the axis of the core shaft (3b), the piston rods (4a) have the same telescopic stroke, a first oil circuit (13b) and a pair of second oil circuits (113b) are provided on the core shaft (3b), a first oil pipe (4b) connected to and matched with the first oil circuit (13b) and two second oil pipes (4c) correspondingly connected to the second oil circuit (113b) are provided on the bidirectional oil cylinder (4), an oil circuit interface (5) correspondingly matched with the first oil circuit (13b) and the pair of second oil circuits (113b) is provided on the housing (1), and a hydraulic pump station correspondingly matched with the oil circuit interface (5) and the mechanical arm (2) is provided in the mounting seat (2a).

2. A clamping device for grinding a wheel hub according to claim 1, characterized in that: The piston rod (4a) comprises a rod body (14a), one end of which is sleeved with a piston (14b) corresponding to the inner wall of a cylinder body (14d), and the other end of the rod body (14a) extends out of the cylinder and is connected to a connecting seat (3g).

3. The clamping device for grinding a wheel hub according to claim 1, characterized in that: The mechanical arm (2) comprises: a first main arm (2f) hinged on a mounting seat (2a), a base (1) also being provided on the mounting seat (2a) to form a correspondingly matched rotary hydraulic reducer (2g); a second main arm (2b) and a connecting plate (2c) being hinged on one end of the first main arm (2f) via a hinge shaft, a first auxiliary arm (2d) being hinged between the connecting plate (2c) and the mounting seat (2a), and a second auxiliary arm (2e) being hinged on the connecting plate (2c). ), a rotating clamping device mounting frame (2h) connected to the rotating clamping device (3) is hingedly connected at one end of the second auxiliary arm (2e) and the second main arm (2b); a swing rod (2t) is also hingedly connected to the mounting seat (2a), a second main arm retaining rod (2j) is hingedly connected to the swing rod (2t), one end of the second main arm retaining rod (2j) is hingedly connected to the second main arm (2b), a second main arm driven retaining rod (2k) is also provided between the mounting seat (2a) and the connecting plate (2c), and the swing rod (2t) forms a power control coordination with the first main arm (2f) and the hydraulic pump station.

4. A clamping device for grinding a wheel hub according to claim 2 or 3, characterized in that: A spring (6) is sleeved on the rod body (14a) of each piston rod (4a), one end of the spring (6) contacts the end of the oil cylinder, and the other end contacts the piston (14b).

5. A clamping device for grinding a wheel hub according to claim 2 or 3, characterized in that: One end of the rod body (14a) of each piston rod (4a) extends to the other side of the piston (14b) to form a limiting section, and the limiting sections of the two piston rods (4a) are of the same length and are coaxially distributed horizontally.

6. The clamping device for grinding a wheel hub according to claim 1, characterized in that: The core shaft (3b) forms a transmission match with the rotary hydraulic motor (3c) via a coupling (7).

7. The clamping device for grinding a wheel hub according to claim 2, characterized in that: The second oil pipe (4c) is located at both end portions of the bidirectional oil cylinder (4), and the first oil pipe (4b) is located in the middle of the bidirectional oil cylinder (4), with its axis being colinear with the axis of the core shaft (3b).

8. The clamping device for grinding a wheel hub according to claim 3, characterized in that: The hydraulic pump station comprises a first main arm driving hydraulic motor (50) corresponding to the first main arm (2f), a second main arm driving hydraulic motor (51) corresponding to the swing rod (2t), and a mounting rotation reduction device 2g corresponding to the mounting seat (2a).

9. The clamping device for grinding a wheel hub according to claim 8, characterized in that: A power hydraulic system is provided in the hydraulic pump station, comprising a load-sensitive pump (52). The output pipeline of the load-sensitive pump (52) is connected in parallel with a hydraulic control circuit of a rotary hydraulic motor (3c), a hydraulic control circuit of a rotary hydraulic reducer (2g), a hydraulic control circuit of a first main arm driving hydraulic motor (50) and a hydraulic control circuit of a second main arm driving hydraulic motor (51). A load-sensitive multi-way valve (67) is provided in each hydraulic control circuit. A balancing valve (61) is also provided in the hydraulic control circuit of the first main arm driving hydraulic motor (50) and the hydraulic control circuit of the second main arm driving hydraulic motor (51). A brake cylinder (69) is also provided in the hydraulic control circuit of the rotary hydraulic reducer (2g). The hydraulic pump station is also provided with an accumulator (58) corresponding to the first main arm driving hydraulic motor (50) and the second main arm driving hydraulic motor (51).

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