CENTRIFUGAL BRAKE WITH LINEAR CONTROL DRIVE FOR VEHICLE CARDAN SHAFT

Abstract

This utility model relates to mechanical engineering, specifically vehicle braking systems, and can be used as an additional brake installed on a driveshaft to enhance braking efficiency. A centrifugal brake for a vehicle driveshaft is a braking system. It comprises a fixed housing, a rotating hub, and weights with rods and friction linings mounted in guides with springs that press them radially inward. It also includes a clutch with rigidly fixed pins, axially movable, connected via a thrust bearing to the output link of a linear drive (solenoid, hydraulic cylinder, pneumatic cylinder, or linear actuator). In the initial position, the pins engage in holes in the weights, securing them in place.When a signal is applied, the linear actuator shifts the clutch and pins, releasing the weights. Centrifugal force presses the weights' heads and pads against the housing, creating a braking torque (the clutch remains engaged with the guides). When the signal is released, the linear actuator's return spring returns the clutch and pins, and the weight springs return them to their original position. The result is increased braking efficiency due to the controlled additional braking torque on the driveshaft.

Description

[0001] The utility model relates to the field of mechanical engineering, in particular to the braking devices of vehicles, and can be used as an additional brake installed on a cardan shaft to improve braking efficiency.

[0002] Various braking devices are known from the prior art.

[0003] Classic wheel hub brakes are well-known. The disadvantage is wear and tear under intensive use.

[0004] Engine brakes (retarders) are known. The disadvantage is their complexity and low effectiveness at low speeds.

[0005] A centrifugal brake is known from USSR Author's Certificate SU 830054 (published April 30, 1980). It contains spring-loaded shoes on a shaft that are pressed against the housing by centrifugal force. A drawback is that it operates automatically without control.

[0006] A centrifugal brake with a ratchet mechanism (patent US 9,151,349 B2) for emergency stopping, with a single action, is known.

[0007] The closest analogue (prototype) is a centrifugal brake according to author's certificate SU 830054, comprising a fixed housing, a rotating hub, and spring-loaded weights. Disadvantages of the prototype: lack of positive locking of the weights, inability to be controlled by the main brake system, and automatic activation.

[0008] The technical problem is the creation of a controlled centrifugal brake for the cardan shaft, which is activated by a command from the standard braking system.

[0009] The technical result is to increase braking efficiency due to controlled additional braking torque on the cardan shaft.

[0010] The technical result is achieved by a centrifugal brake with a linear control drive for a vehicle's driveshaft. It comprises a stationary cylindrical housing secured to the vehicle's frame or body and enclosing the driveshaft, and a rotating hub mounted on the driveshaft. A coupling is mounted on the hub with axial movement, to which transverse pins are rigidly attached. The coupling and pins are connected via a support bearing to the output link of a linear drive, which is rigidly secured to the vehicle's body. The linear drive is equipped with a return spring, which presses the coupling and pins in the direction of the locking point (toward the weights).

[0011] The guides, rigidly connected to the hub, contain weights. Each weight is a rod with a head containing a friction lining made of friction material at one end. A hole is drilled in the middle of the rod for engagement with the pin. The other end of the rod has a thread, recess, or hole for attaching a spring. The weight is inserted into the guide, which also contains a coaxial hole for the pin. A spring is mounted on the rod of the weight, between the guide and the end fastener (nut or washer), pressing the weight toward the pin (i.e., radially inward, toward the hub). In the initial position, the pins enter the holes in the weights, preventing them from moving radially.

[0012] When a control signal is applied from the standard brake system, the linear actuator overcomes the force of its return spring and moves the output link and, through the bearing, the clutch with the pins axially a predetermined distance. This distance is sufficient for the pins to exit the holes in the weights, releasing them, but insufficient for the clutch to disengage from the guides (i.e., the clutch remains engaged with the guides, rotating with the cardan shaft). Once released, the weights, under the centrifugal force of the shaft rotation, overcome the force of their springs and move radially in the guides until their heads with the friction lining rest against the stationary cylindrical housing, creating additional braking torque.

[0013] When the control signal is disconnected, the linear actuator's return spring returns the output link and clutch with pins to their original positions. As the driveshaft speed decreases, the centrifugal force decreases, and the flyweight springs return them to their original radial position. The flyweight pins then engage the flyweight holes, locking them in place once again.

[0014] The thrust bearing installed between the coupling and the output link of the linear drive prevents wear of the fork (output link) when the coupling rotates together with the cardan shaft.

[0015] The utility model is explained by a drawing, where Fig. 1 shows a schematic longitudinal section of a centrifugal brake.

[0016] The drawing shows:

[0017] 1 - cardan shaft;

[0018] 2 - fixed cylindrical body;

[0019] 3 - rotating hub;

[0020] 4 - coupling with pins;

[0021] 5 - linear drive;

[0022] 6 - linear drive output link;

[0023] 7 - linear drive return spring;

[0024] 8 - support bearing;

[0025] 9 - weight guide;

[0026] 10 - weight (rod);

[0027] 11 - head with friction lining;

[0028] 12 - hole in the weight (not shown in the figure);

[0029] 13 - weight spring;

[0030] 14 - end fastener (nut / washer);

[0031] 15 - fixed body of the vehicle (frame).

[0032] Implementation of a utility model.

[0033] In the initial state, the linear actuator (5) is de-energized, the return spring (7) holds the output link (6) and the clutch with pins (4) in the locked position. The pins enter the holes (12) of the weights (10), holding them. The springs of the weights (13) are compressed (or are in equilibrium). The weights do not touch the housing (2). When the brake pedal is pressed, a signal is sent to the linear actuator. The linear actuator moves the output link, compressing the return spring (7). Through the bearing (8), the force is transmitted to the clutch (4), which is displaced axially by a predetermined distance. The pins exit the holes (12) of the weights, releasing them. Under the action of centrifugal force, the weights move radially until the head with the lining (11) stops in the housing (2), compressing their springs (13). A braking torque is generated. When the pedal is released, the signal is removed, and the return spring (7) returns the output link and clutch to their original position. As the speed decreases, the springs (13) return the weights to their original position, and the pins re-lock them.

[0034] Industrial applicability.

[0035] The device can be made from standard components: linear drives (retractor solenoids, hydraulic cylinders, pneumatic cylinders, electromechanical actuators), thrust bearings (clutch release bearings), springs, friction linings, steel parts.

Claims

1. A centrifugal brake for a driveshaft of a vehicle comprising a stationary cylindrical housing secured to the frame or body of the vehicle, a rotating hub mounted on the driveshaft, and weights having friction linings placed on the hub with the possibility of radial movement, characterized in that a clutch with transverse pins rigidly secured to it is mounted on the hub with the possibility of axial movement, and the clutch is connected through a support bearing to the output link of a linear drive fixedly secured to the body of the vehicle, wherein the linear drive is provided with a return spring pressing the clutch with pins in the direction of fixing the weights, wherein the weights are made in the form of rods, at one end of which there is a head with a friction lining, and in the middle part an opening is made for interaction with the pin, wherein the weights are mounted in guides rigidly connected to the hub,in each of which a coaxial hole is made for the passage of the pin, at the other end of the weight rod an end element is secured, and between this element and the guide a spring is installed that presses the weight radially inward, and the stroke of the coupling with the pins is selected such that when the linear drive is triggered, the pins come out of the holes of the weights, releasing them, but the coupling remains in engagement with the guides, and when the drive is disconnected, the return spring returns the coupling with the pins to the original fixation position.

2. The brake according to paragraph 1, characterized in that the linear drive is made in the form of a retractor electromagnet.

3. The brake according to paragraph 1, characterized in that the linear drive is made in the form of a hydraulic cylinder.

4. The brake according to paragraph 1, characterized in that the linear drive is made in the form of a pneumatic cylinder.

5. The brake according to paragraph 1, characterized in that the linear drive is made in the form of an electromechanical linear actuator.

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