DUSTPROOF COVER FOR BRAKE CYLINDER AND WATERPROOF BRAKE CYLINDER USING DUSTPROOF COVER

Field of the Invention

The invention belongs to the technical field of brake cylinder for vehicle, in particular to a brake cylinder dust cover and a waterproof brake cylinder using such dust cover.

Description of the Related Art

A brake cylinder for a railway vehicle is generally mounted at the bottom of the vehicle, and the body of the vehicle (e.g. gondola car and box car) will prevent rain water from entering the cylinder. However, the bodies of some types of vehicles (e.g. flat car, tank car and cement truck) do not shelter the whole brake cylinders, so that rain water is easy to fall down to and enter the brake cylinder.

As shown in Figure 1, an existing brake cylinder for a railway vehicle has a dustproof function only and lacks waterproof function. Once water falls down to the brake cylinder in rainy days, rain water is very easy to flow from the places A, B and C in Figure 1 into the brake cylinder. Especially when the brake cylinder is released, negative pressure will appear at the right side of the piston of the brake cylinder, so that rain water is easy to be pumped into the cylinder, resulting in pollution and corrosion in the brake cylinder, which greatly reduces the service life of the brake cylinder and affects driving safety. An example belonging to the state of the art is disclosed in JP 2004 345394 A.

Summary of the Invention

To address the problems, the purpose of the invention is to provide a brake cylinder dust cover that can effectively prevent rain water from entering the brake cylinder so as to increase the service life of the brake cylinder and ensure safe driving, and to provide a waterproof brake cylinder using such dust cover.

The technical solution of the invention is realized by a brake cylinder dust according to claim 1.

The brake cylinder dust cover according to the invention, wherein the skirt takes the shape of a bell mouth as a whole.

The brake cylinder dust cover according to the invention, wherein the skirt and the brake cylinder dust cover are formed into an integrated structure

A waterproof brake cylinder using the brake cylinder dust cover comprises a brake cylinder body and a front cover. A waterproof dust cover assembly is arranged on the front cover. The waterproof dust cover assembly comprises a dust cover fixedly connected to the front cover of brake cylinder, and a filter felt support and a filter felt pad which are arranged in the brake cylinder dust cover. The filter felt support is connected with the brake cylinder dust cover, and the filter felt pad is fixed on the filter felt support. An outwards extending skirt is arranged at the edge of the brake cylinder dust cover in the axial direction thereof.

The waterproof brake cylinder according to the invention, wherein an outwards extending boss is arranged at a vent of the brake cylinder dust cover in the axial direction thereof.

The waterproof brake cylinder according to the invention, wherein a waterproof ring seat for mounting a filter cover of front cover is arranged in the front cover, the waterproof ring seat is sleeved on a piston rod of the brake cylinder, a double-lip waterproof ring is arranged on the waterproof ring seat and between the waterproof ring seat and the piston rod, and an O seal ring is arranged on the waterproof ring seat and between the waterproof ring seat and the front cover.

The waterproof brake cylinder according to the invention, wherein a ring slot is arranged at the outer end face of the waterproof ring seat, and the O seal ring is assembled in the ring slot.

By providing an existing brake cylinder with a sealing structure at the position liable to water, the invention can effectively prevent rain water from being sucked into the cylinder by the negative pressure formed in the brake cylinder when the brake cylinder is released, thus playing the waterproof role, which increases the service life of the cylinder and ensures safe driving.

Brief Description of the Drawings

• Figure 1 is a diagram illustrating a conventional front cover assembly for a brake cylinder;
• Figure 2 is a structural diagram of the invention;
• Figure 3 is an enlarged view of the waterproof dust cover assembly in Figure 2;
• Figure 4 is a waterproof diagram of the front cover end in the invention; and
• Figure 5 is a structural diagram of a waterproof ring seat of the invention.

Marks in the figures: 1-brake cylinder body; 2-front cover; 3-waterproof dust cover assembly; 4-brake cylinder dust cover; 5-filter felt support; 6- filter felt pad; 7-skirt; 8-boss; 9-ring slot; 10-filter cover of front cover; 11-waterproof ring seat; 12-piston rod; 13-double-lip waterproof ring; 14-O seal ring B; and 15-release spring.

Description of the Preferred Embodiment

The invention will be described in detail in combination with accompanied drawings.

In order to make the purpose, technical solution and advantages of the invention more clear, the invention will be described in detail in combination with accompanied drawings and embodiments. It should be understood that various embodiments described herein are only used to explain the invention rather than defining the invention.

As shown in Figure 2 and Figure 3, a waterproof brake cylinder comprises a brake cylinder body 1 and a front cover 2. A waterproof dust cover assembly 3 is arranged on the front cover 2. The waterproof dust cover assembly 3 comprises a brake cylinder dust cover 4 fixedly connected to the front cover 2, and a filter felt support 5 and a filter felt pad 6 which are arranged in the brake cylinder dust cover 4. The filter felt support 5 is connected with the brake cylinder dust cover 4, and the filter felt pad 6 is fixed on the filter felt support 5. An outwards extending skirt 7 is arranged at the edge of the brake cylinder dust cover 4 in the axial direction thereof. The skirt 7 and the brake cylinder dust cover 4 are formed into an integrated structure. The skirt 7 takes the shape of a bell mouth as a whole. An outwards extending boss 8 is arranged at a vent of the brake cylinder dust cover 4 in the axial direction thereof, thus further preventing rain water from entering the dust cover.

As shown in Figure 3, when rain water flows down along the brake cylinder dust cover, rain water will fall down along the skirt directly because of the water retaining effect of the skirt on the brake cylinder dust cover so as to isolate the gas passage from the flowing path of rain water, which plays a waterproof role. When the brake cylinder is released, negative pressure is formed above the filter felt pad of a filter assembly. However, as rain water cannot reach the place C of the brake cylinder dust cover due to the block from the skirt, rain water will not be sucked into the cylinder. Even if a small part of the rain water flows to the place C, rain water will be stopped by the boss at the place C again, which ensures that rain water can not enter the brake cylinder dust cover.

As shown in Figure 4, a waterproof ring seat 11 for mounting the filter cover 10 of front cover is arranged in the front cover 2, and the waterproof ring seat 11 is sleeved on the piston rod 12 of the brake cylinder. A double-lip waterproof ring 13 is arranged on the waterproof ring seat 11 and between the waterproof ring seat 11 and the piston rod 12. The double-lip waterproof ring is made from high-hardness polyurethane, which reduces friction with the piston rod, and can prevent rain water from entering the cylinder body from the place A. An O seal ring 14 is arranged on the waterproof ring seat 11 and between the waterproof ring seat 11 and the front cover 2. As shown in Figure 5, a ring slot 9 is arranged at the outer end surface of the waterproof ring seat 11, and the O seal ring 14 is assembled in the ring slot 9. With the acting force of a release spring 15, the O seal ring 14 deforms and plays a sealing role, which prevents rain water from entering the cylinder from the place B between the front cover and a dust ring mounting base. The filter cover of front cover is sealed through the O seal ring and the double-lip waterproof ring, which avoids direct contact with the atmosphere, reduces volatilization of 89M lubricating grease stored in the cover, slows oxidative deterioration down and is useful for lubrication and rust protection of the piston rod.

The invention makes structural improvement for the three water leakage positions A, B and C in Figure 1. The invention provides a seal structure to play a waterproof role, thus effectively preventing pollution and corrosion in the brake cylinder due to rain water, which greatly reduces the service life of the brake cylinder and ensures safe driving.

The above mentioned examples are preferred examples of the invention only and not used to limit the invention.