An actuator and method for a wheeled excavator parking brake

Abstract

This invention provides an actuator and method for a parking brake on a wheeled excavator, relating to the field of vehicle braking. The actuator and method for the parking brake on a wheeled excavator include a transmission mechanism housing and a transmission actuator. A cover is bolted to one side of the transmission mechanism housing. A motor for driving the transmission actuator is installed inside the transmission mechanism housing. The output end of the transmission actuator is connected to a push mechanism for driving the brake pads. This actuator and method for the parking brake on a wheeled excavator introduces a controllable friction interface in the transmission chain. When braking encounters abnormal resistance or reaches a preset torque peak, this interface can slip, actively releasing excess torque. This not only effectively avoids instantaneous damage to key transmission components such as the motor, gears, and screw caused by rigid impacts, but also greatly improves the durability and reliability of the system throughout its entire lifespan.

Description

Technical Field

[0001] This invention relates to the field of vehicle braking technology, specifically to an actuator and method for a parking brake of a wheeled excavator. Background Technology

[0002] As a type of construction machinery combining high mobility and complex operational functions, the driving and parking safety of wheeled excavators is crucial to the overall reliability of the machine. The parking brake is a core safety device that ensures the equipment remains stable and prevents slippage on slopes, flat ground, and under various working conditions. With the continuous improvement of electrification and intelligence in construction machinery, parking brake systems using electric drive actuators have become the mainstream technology due to their precise control, rapid response, ease of automatic control, and integration of advanced safety functions.

[0003] Currently, the actuators of electric parking brakes in wheeled excavators suffer from rigid impacts during braking force application and lack effective release of peak torque. Furthermore, their force distribution relies on an uncontrollable passive floating mechanism, failing to guarantee real-time balance of clamping forces on both sides. These two defects combined not only allow the braking process itself to cause impact damage to components but also lead to rapid performance degradation and unpredictability of the braking system throughout its service life. This not only contradicts the original intention of electric drive technology to pursue precision and controllability but also introduces additional safety risks and operating costs. Summary of the Invention

[0004] (a) Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this invention provides an actuator and method for a parking brake of a wheeled excavator, which solves the problems of rigid impact during the application of braking force, lack of effective release of peak torque, reliance on an uncontrollable passive floating mechanism in force distribution, and inability to ensure balanced clamping force on both sides.

[0006] (II) Technical Solution

[0007] To achieve the above objectives, the present invention provides the following technical solution: an actuator and method for a parking brake of a wheeled excavator, comprising a transmission mechanism housing and a transmission actuator. One side of the transmission mechanism housing is fixed with a cover by bolts. A motor for driving the transmission actuator is installed inside the transmission mechanism housing. The output end of the transmission actuator is connected to a pushing mechanism for driving the brake pads. A pressing mechanism for synchronously moving the brake pads is connected to the pushing mechanism. The transmission mechanism housing is connected to a brake seat through a connecting chamber. The brake seat is fixed to one of the brake pads by a positioning rod. The positioning rod passes through the brake seat and is sleeved with a connecting spring inside the connecting chamber.

[0008] Preferably, the transmission actuator includes a drive gear, a reduction gear, a transmission shaft, a support member, a transmission gear, a clutch gear, a damping plate, an adjusting bolt, a pressure spring, a transmission ring, a transmission frame, a transmission rod, and transmission teeth. The output end of the motor is fixed to the drive gear. The drive gear is connected to the reduction gear. The reduction gear is connected to the transmission gear via the transmission shaft. The transmission shaft is rotatably supported by the support member. The transmission gear is connected to the clutch gear. The inner ring of the clutch gear is movably sleeved with the transmission rod via a bearing. The end of the transmission rod is threadedly connected to the adjusting bolt. A pressure spring is sleeved on the adjusting bolt. The end of the clutch gear away from the pressure spring is connected to the damping plate. The damping plate is in contact with the transmission ring. The end of the transmission ring away from the damping plate is fixedly connected to the transmission frame. The transmission frame is fixedly sleeved with the transmission rod. Transmission teeth are provided at the end of the transmission rod away from the adjusting bolt.

[0009] Preferably, the damping sheet is made of a semi-metallic material or an asbestos-free environmentally friendly material.

[0010] Preferably, the pressure spring abuts against the bearing that is fitted onto the inner ring of the clutch gear.

[0011] Preferably, the pushing mechanism includes a sleeve, spline teeth, a pushing screw, a pushing sleeve, a T-shaped slider, and a slide rail. The transmission teeth are driven and sleeved with the spline teeth provided on the inner tube of the sleeve. The end of the sleeve is fixed to the pushing screw. The pushing screw is threaded and sleeved with the pushing sleeve. The outer surface of the pushing sleeve is fixed to the T-shaped slider. The T-shaped slider is slidably connected to the slide rail. The top of the slide rail is fixed to the top of the inner wall of the connecting chamber.

[0012] Preferably, the extrusion mechanism includes an extrusion chamber, a pressing piston, a hydraulic clamping mechanism, and a return spring. The end of the pushing sleeve is fixed to the pressing piston, the pressing piston is slidably connected to the extrusion chamber, and the end of the extrusion chamber away from the pushing sleeve passes through the brake seat and abuts against the brake pads provided inside the brake seat.

[0013] Preferably, a hydraulic clamping mechanism is connected to another brake pad inside the brake seat, and a return spring is also provided on the other brake pad.

[0014] Preferably, the hydraulic clamping mechanism is a piston type, and the hydraulic clamping mechanism is connected to the extrusion chamber through a pipeline.

[0015] Preferably, the spiral path of the push screw is embedded with balls.

[0016] Preferably, a method for actuating the parking brake of a wheeled excavator includes the following steps:

[0017] S1: When braking is required, the motor is rotated by sending an electrical signal. The rotation of the motor is transmitted to the push mechanism through the deceleration operation of the transmission actuator.

[0018] S2: The push screw and push sleeve, through the rotation of the transmission actuator, squeeze the pressure piston and simultaneously push the brake pads closer to the brake disc;

[0019] S3: The compression of the piston and the compression chamber transmits the brake fluid to the hydraulic clamping mechanism. The push rod of the hydraulic clamping mechanism transmits power to the other brake pad through hydraulic pressure, so that the two brake pads come closer to each other and squeeze the brake disc, thereby achieving braking.

[0020] S4: When the brake needs to be released, the motor reverses to make the piston return, and the expansion force of the connecting spring and the return force of the return spring realize the return operation of the two brake pads.

[0021] (III) Beneficial Effects

[0022] This invention provides an actuator and method for a parking brake on a wheeled excavator. It offers the following advantages:

[0023] 1. The actuator and method of the parking brake for this wheeled excavator introduce a controllable friction interface in the transmission chain. When braking encounters abnormal resistance or reaches a preset torque peak, this interface can slip, actively releasing excess torque. This not only effectively avoids instantaneous damage to key transmission components such as motors, gears, and screws caused by rigid impacts, but also transforms the braking process from an impact-based to a smooth application, greatly improving the system's durability and reliability throughout its life cycle, and effectively eliminating the risk of sudden failures due to overload.

[0024] 2. The actuator and method of the parking brake of the wheeled excavator can change the preload of the pressure spring by rotating the adjusting bolt, thereby flexibly setting the torque threshold of overload protection, so that the system can adapt to different vehicle models or working conditions.

[0025] 3. The actuator and method of the parking brake for this wheeled excavator: This invention transmits pressure through a hydraulic system. During braking, the mechanical thrust input from one side is converted into hydraulic pressure, which is instantaneously and equally transmitted to the hydraulic clamping mechanism on the other side through pipelines. This mechanism ensures that the clamping force obtained by the brake pads on both sides is theoretically completely equal and can be dynamically adjusted in real time, achieving true forced synchronization and force balance. This directly solves the problems of uneven brake disc wear and brake vibration, making braking performance more stable and predictable, and significantly extending the service life of the brake disc and brake pads.

[0026] 4. The actuator and method of the parking brake of the wheeled excavator adopt a closed hydraulic circuit to connect the braking units on both sides, ensuring that the two brake pads are subjected to uniform force and move synchronously, and the braking process is smooth, effectively avoiding problems such as uneven wear and vibration of the brake disc caused by unilateral braking or asynchronous braking. Attached Figure Description

[0027] Figure 1 This is a perspective view of the overall structure of the present invention;

[0028] Figure 2 This is a schematic diagram of the overall structure of the present invention;

[0029] Figure 3 This is a schematic diagram of the internal structure of the transmission mechanism housing of the present invention;

[0030] Figure 4 This is a schematic diagram of the transmission actuator and the actuation mechanism of the present invention;

[0031] Figure 5 This is a partial structural diagram of the transmission actuator of the present invention;

[0032] Figure 6 This is a plan view of the actuator and the actuation mechanism of the present invention;

[0033] Figure 7 For the present invention Figure 6 Sectional view of the structure at point AA;

[0034] Figure 8 This is a schematic diagram of a partial structure of the driving mechanism of the present invention;

[0035] Figure 9 This is a schematic diagram of the internal structure of the connecting compartment of the present invention;

[0036] Figure 10 This is a schematic diagram of the brake seat and extrusion mechanism of the present invention.

[0037] The components include: 1. Transmission mechanism housing; 2. Cover; 3. Motor; 4. Transmission actuator; 401. Drive gear; 402. Reduction gear; 403. Transmission shaft; 404. Support component; 405. Transmission gear; 406. Clutch gear; 407. Bearing; 408. Damping plate; 409. Adjusting bolt; 410. Pressure spring; 411. Transmission ring; 412. Transmission frame; 413. Transmission rod; 414. Transmission gear; 5. Pushing mechanism; 501. Sleeve; 502. Spline gear; 503. Push screw; 504. Push sleeve; 505. T-slider; 506. Slide rail; 6. Extrusion mechanism; 601. Extrusion chamber; 602. Pressing piston; 603. Hydraulic clamping mechanism; 604. Return spring; 7. Connecting chamber; 8. Brake seat; 9. Brake pad; 10. Positioning rod; 11. Connecting spring. Detailed Implementation

[0038] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0039] This invention provides an actuator and method for a parking brake on a wheeled excavator, such as... Figure 1-10 As shown, the device includes a transmission mechanism housing 1 and a transmission actuator 4. A cover 2 is fixed to one side of the transmission mechanism housing 1 by bolts. A motor 3 for driving the transmission actuator 4 is installed inside the transmission mechanism housing 1. A push mechanism 5 for driving the brake pad 9 is connected to the output end of the transmission actuator 4. A pressing mechanism 6 for synchronously moving the brake pad 9 is connected to the push mechanism 5. The forward or reverse rotation of the motor 3 can drive the transmission actuator 4 and the push mechanism 5 to operate. The linear movement of the push mechanism 5 can push the pressing mechanism 6 and drive the brake pad 9 to move closer or further away, thereby achieving braking or releasing the brake disc.

[0040] The transmission mechanism housing 1 is connected to the brake seat 8 through the connecting chamber 7. The brake seat 8 is fixed to one of the brake pads 9 through the positioning rod 10. The positioning rod 10 passes through the brake seat 8 and is sleeved with the connecting spring 11 set inside the connecting chamber 7. The positioning rod 10 can realize the directional movement of the brake pad 9 and realize the stability of the connection between the brake pad 9 and the brake disc.

[0041] The transmission actuator 4 includes a drive gear 401, a reduction gear 402, a transmission shaft 403, a support 404, a transmission gear 405, a clutch gear 406, a damping plate 408, an adjusting bolt 409, a pressure spring 410, a transmission ring 411, a transmission frame 412, a transmission rod 413, and a transmission gear 414. The output end of the motor 3 is fixed to the drive gear 401. The drive gear 401 is connected to the reduction gear 402. The drive gear 401 and the reduction gear 402 have a large transmission ratio, which can realize the transmission rod 413 with a large torque.

[0042] The reduction gear 402 is connected to the transmission gear 405 via the transmission shaft 403. The transmission shaft 403 is rotatably supported by the support member 404. The transmission gear 405 is connected to the clutch gear 406. The transmission ratio between the transmission gear 405 and the clutch gear 406 is also set to a large ratio, which can further realize a larger torque transmission.

[0043] The inner ring of the clutch gear 406 is movably sleeved with the transmission rod 413 via the bearing 407. The end of the transmission rod 413 is threadedly connected to the adjusting bolt 409. The adjusting bolt 409 is sleeved with a pressure spring 410. The end of the clutch gear 406 away from the pressure spring 410 is connected to the damping plate 408. The damping plate 408 is in contact with the transmission ring 411. The end of the transmission ring 411 away from the damping plate 408 is fixedly connected to the transmission frame 412. The transmission frame 412 is fixedly sleeved with the transmission rod 413. The end of the transmission rod 413 away from the adjusting bolt 409 is provided with a transmission tooth 414. The clutch gear 406 is pressure-fitted to the transmission ring 411 via the damping plate 408, which can provide unloading force when a large resistance peak occurs during the transmission of the transmission rod 413, effectively protecting the transmission mechanism and reducing the pressure on the brake pad 9.

[0044] The 408 damping pad is made of semi-metallic, asbestos-free environmentally friendly material or carbon fiber material. The metallic component has good thermal conductivity, which can quickly reduce the heat generated by friction. The asbestos-free environmentally friendly material has a relatively soft texture and stable friction characteristics, which can effectively reduce braking squeal, vibration and other issues.

[0045] The pressure spring 410 abuts against the bearing 407 that is sleeved on the inner ring of the clutch gear 406. By adjusting the length of the adjusting bolt 409 extending into the transmission rod 413, the pressure of the pressure spring 410 acting on the clutch gear 406 can be adjusted, and the friction value between the clutch gear 406 and the transmission rod 413 can be adjusted. By adjusting the unloading value, the pressure of the transmission rod 413 and the squeezing mechanism 6 acting on the brake pad 9 can be reduced, thereby achieving the unloading operation of the peak torque.

[0046] The pushing mechanism 5 includes a sleeve 501, a spline tooth 502, a pushing screw 503, a pushing sleeve 504, a T-shaped slider 505, and a slide rail 506. The transmission tooth 414 is driven and sleeved with the spline tooth 502 set in the inner tube of the sleeve 501. The end of the sleeve 501 is fixed to the pushing screw 503. The pushing screw 503 is threaded and sleeved with the pushing sleeve 504. The outer surface of the pushing sleeve 504 is fixed to the T-shaped slider 505. The T-shaped slider 505 is slidably connected to the slide rail 506. The top of the slide rail 506 is fixed to the top of the inner wall of the connecting chamber 7. The transmission rod 413 drives the pushing screw 503 to rotate. Through the threaded connection between the pushing screw 503 and the pushing sleeve 504, the axial movement of the pushing sleeve 504 can be realized, which can then push the extrusion mechanism 6 to move and drive the internal pressure piston 602 to pressurize the brake fluid inside the extrusion mechanism 6.

[0047] The extrusion mechanism 6 includes an extrusion chamber 601, a pressing piston 602, a hydraulic clamping mechanism 603, and a return spring 604. The end of the pushing sleeve 504 is fixed to the pressing piston 602. The pressing piston 602 is sealed and slidably connected to the extrusion chamber 601. The end of the extrusion chamber 601 away from the pushing sleeve 504 passes through the brake seat 8 and abuts against the brake pad 9 provided inside the brake seat 8. The axial movement of the pushing sleeve 504 can drive the extrusion mechanism 6 to move and drive the brake pad 9 to achieve braking of the brake disc.

[0048] A hydraulic clamping mechanism 603 is connected to another brake pad 9 inside the brake seat 8, and a return spring 604 is also provided on the other brake pad 9.

[0049] The hydraulic clamping mechanism 603 is a piston type. The hydraulic clamping mechanism 603 is connected to the extrusion chamber 601 through a pipeline. The extrusion chamber 601 is connected to the hydraulic clamping mechanism 603 through a pipeline. This enables hydraulic linkage between the extrusion chamber 601 and the hydraulic clamping mechanism 603, thereby achieving relative displacement between the two brake pads 9 and thus braking the brake disc.

[0050] Ball bearings are embedded in the spiral path of the drive screw 503. The optional ball bearings have the advantages of high transmission efficiency and small backlash.

[0051] A method for actuating the parking brake of a wheeled excavator includes the following steps:

[0052] S1: When braking is required, the motor 3 is rotated by giving an electrical signal. The rotation of the motor 3 is transmitted to the push mechanism 5 through the deceleration operation of the transmission actuator 4.

[0053] S2: The push screw 503 and push sleeve 504, through the rotation of the transmission actuator 4, squeeze the pressure piston 602 and simultaneously push the brake pad 9 toward the brake disc;

[0054] S3: The compression of the piston 602 and the compression chamber 601 transmits the brake fluid to the hydraulic clamping mechanism 603. The push rod of the hydraulic clamping mechanism 603 transmits power to the other brake pad 9 through hydraulic pressure, so that the two brake pads 9 come closer to each other and squeeze the brake disc, thereby achieving braking.

[0055] S4: When it is necessary to release the brake, the reverse rotation of the motor 3 is used to make the piston 602 return, and the expansion force of the connecting spring 11 and the return force of the return spring 604 are used to make the two brake pads 9 return to their original positions.

[0056] Working principle: When braking is required, the control system sends a forward rotation signal to motor 3; the motor outputs power, which first reduces the torque significantly by a large transmission ratio through drive gear 401 and reduction gear 402. The increased torque is then transmitted to transmission gear 405 via transmission shaft 403, and then drives clutch gear 406. Clutch gear 406, through the pressure generated by pressure spring 410, generates friction with transmission ring 411 fixed on transmission frame 412 by damping plate 408, thereby transmitting torque to transmission rod 413. This friction pair constitutes a key overload protection mechanism: if the resistance to pushing the brake pad 9 is too great, such as reaching the preset peak torque, slippage will occur between the clutch gear 406 and the transmission ring 411, effectively relieving the force and protecting the subsequent transmission components from overload damage. The transmission teeth 414 at the end of the transmission rod 413 drive the spline teeth 502 inside the sleeve 501 to rotate, thereby causing the push screw 503 to rotate. Under the constraint of the threaded pair, the T-shaped slider 505 and the slide rail 506, the push sleeve 504 converts the rotational motion into precise linear motion. The forward linear motion of the push sleeve 504 produces two synchronous effects: its end directly pushes the push-press piston 602 to move the brake pad 9 on one side towards the brake disc. At the same time, it pushes the push-press piston 602 to move in the compression chamber 601, pressurizing the brake fluid in the chamber. Pressure is instantly transmitted through the pipeline to the hydraulic clamping mechanism 603 on the other side, driving its push rod to extend and push the brake pads 9 on the other side to move towards each other. Under the combined action of mechanical push and hydraulic drive, the brake pads 9 on both sides smoothly and synchronously clamp the brake disc, achieving reliable parking brake.

[0057] When the brake needs to be released, the control system reverses the motor 3, the transmission chain runs in reverse, and the screw 503 drives the push sleeve 504 and the pressure piston 602 to retract. The elastic restoring force of the connecting spring 11 pulls the positioning rod 10, so that the brake pad 9 on that side is reset. As the hydraulic pressure in the extrusion chamber 601 is released, the push rod of the hydraulic clamping mechanism 603 retracts under the action of the return spring 604, driving the brake pad 9 on that side to reset. Both brake pads 9 on both sides disengage from the brake disc at the same time, and the brake is completely released.

[0058] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. An actuator for a parking brake of a wheel excavator, comprising a transmission housing (1) and a transmission actuator (4), characterized in that: A cover (2) is fixed to one side of the housing (1) of the transmission mechanism by bolts. A motor (3) for driving the transmission actuator (4) is installed inside the housing (1). A push mechanism (5) for driving the brake pad (9) is connected to the output end of the transmission actuator (4). A squeezing mechanism (6) for synchronously moving the brake pad (9) is connected to the push mechanism (5). The transmission mechanism housing (1) is connected to the brake seat (8) through the connecting chamber (7). The brake seat (8) is fixed to one of the brake pads (9) through the positioning rod (10). The positioning rod (10) passes through the brake seat (8) and is sleeved with the connecting spring (11) provided inside the connecting chamber (7). The transmission actuator (4) includes a drive gear (401), a reduction gear (402), a transmission shaft (403), a support member (404), a transmission gear (405), a clutch gear (406), a damping plate (408), an adjusting bolt (409), a pressure spring (410), a transmission ring (411), a transmission frame (412), a transmission rod (413), and a transmission gear (414). The output end of the motor (3) is fixed to the drive gear (401). The drive gear (401) is connected to the reduction gear (402) in a transmission connection. The reduction gear (402) is connected to the transmission gear (405) through the transmission shaft (403). The transmission shaft (403) is rotated and supported by the support member (404). The transmission gear (405) is connected to the clutch gear (406). The clutch gear (406) is connected to the transmission. The inner ring of the clutch gear (406) is movably sleeved with the transmission rod (413) through the bearing (407). The end of the transmission rod (413) is threadedly connected to the adjusting bolt (409). The adjusting bolt (409) is sleeved with a pressure spring (410). The end of the clutch gear (406) away from the pressure spring (410) is connected to the damping plate (408). The damping plate (408) is in contact with the transmission ring (411). The end of the transmission ring (411) away from the damping plate (408) is fixedly connected to the transmission frame (412). The transmission frame (412) is fixedly sleeved with the transmission rod (413). The end of the transmission rod (413) away from the adjusting bolt (409) is provided with a transmission tooth (414). The pushing mechanism (5) includes a sleeve (501), a spline tooth (502), a pushing screw (503), a pushing sleeve (504), a T-shaped slider (505), and a slide rail (506). The transmission tooth (414) is driven and sleeved with the spline tooth (502) provided in the inner tube of the sleeve (501). The end of the sleeve (501) is fixed to the pushing screw (503). The pushing screw (503) is threaded and sleeved with the pushing sleeve (504). The outer surface of the pushing sleeve (504) is fixed to the T-shaped slider (505). The T-shaped slider (505) is slidably connected to the slide rail (506). The top of the slide rail (506) is fixed to the top of the inner wall of the connecting chamber (7). The extrusion mechanism (6) includes an extrusion chamber (601), a pressing piston (602), a hydraulic clamping mechanism (603), and a return spring (604). The end of the pushing sleeve (504) is fixed to the pressing piston (602). The pressing piston (602) is sealed and slidably connected to the extrusion chamber (601). The end of the extrusion chamber (601) away from the pushing sleeve (504) passes through the brake seat (8) and abuts against the brake pad (9) provided inside the brake seat (8). A hydraulic clamping mechanism (603) is connected to another brake pad (9) inside the brake seat (8), and a return spring (604) is also provided on the other brake pad (9). The hydraulic clamping mechanism (603) is a piston type, and the hydraulic clamping mechanism (603) is connected to the extrusion chamber (601) through a pipeline.

2. A power brake actuator for a wheel excavator as claimed in claim 1, characterized in that: The damping sheet (408) is made of semi-metallic or asbestos-free environmentally friendly material.

3. A power brake actuator for a wheel excavator as claimed in claim 1, characterized in that: The pressure spring (410) abuts against the bearing (407) that is fitted into the inner ring of the clutch gear (406).

4. The actuator of a parking brake for a wheeled excavator according to claim 1, characterized in that: The drive screw (503) has balls embedded in its spiral path.

5. A method for actuating a parking brake on a wheeled excavator, applicable to the actuator of the parking brake on a wheeled excavator as described in any one of claims 1-4, characterized in that: Includes the following steps: S1: When braking is required, the motor (3) is rotated by giving an electrical signal. The rotation of the motor (3) is transmitted to the push mechanism (5) through the deceleration operation of the transmission actuator (4). S2: The push screw (503) and push sleeve (504) squeeze the pressure piston (602) through the rotation of the transmission actuator (4) and simultaneously push the brake pad (9) closer to the brake disc; S3: The compression of the piston (602) and the compression chamber (601) transmits the brake fluid to the hydraulic clamping mechanism (603). The push rod of the hydraulic clamping mechanism (603) transmits the power to the other brake pad (9) through hydraulic pressure, so that the two brake pads (9) can come close to each other and squeeze the brake disc, thereby achieving braking. S4: When it is necessary to release the brake, the piston (602) is pushed back by the reverse rotation of the motor (3), and the two brake pads (9) are returned to their original positions by the expansion force of the connecting spring (11) and the return force of the return spring (604).

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