Spring brake cylinder with direct mounting of rear housing to front housing

Abstract

The application relates to the technical field of spring brake cylinders, and provides a spring brake cylinder with a rear shell directly fixed with a front shell, which comprises a spring brake cylinder rear shell, the inner wall of the spring brake cylinder rear shell is provided with a middle shell body, the inner wall of the spring brake cylinder rear shell is provided with a spring brake cylinder front shell assembly, the inside of the spring brake cylinder rear shell is movably provided with a piston body, one side of the piston body is provided with an energy storage spring, and the outer wall of the piston body is provided with a Y-shaped sealing ring. The outer edge of the piston body is directly matched with the inner cylindrical surface of the spring brake cylinder rear shell to guide, and a nylon guide ring does not need to be arranged between the piston body and the spring brake cylinder rear shell; meanwhile, the middle flange of the middle shell body is directly matched with the outer cylindrical surface of a piston rod to guide, and a nylon guide ring does not need to be arranged between the middle shell body and the piston rod. Therefore, guide ring parts and corresponding assembly procedures are saved, the assembly efficiency is improved, and the cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of spring brake cylinder technology, and in particular to a spring brake cylinder in which the rear housing and the front housing are directly fixed. Background Technology

[0002] Currently, most piston-type spring brake cylinders on the market adopt a three-section split layout: front shell (vehicle brake chamber shell), middle flange body, and rear shell (energy storage spring chamber cylinder). The front and rear shells cannot be directly connected and fixed, and must rely on the middle flange as a transitional connector to achieve assembly. The front shell and middle body are tightly sealed with multiple clamps, and the middle body and rear shell are locked and fixed by multiple sets of bolts and nuts evenly distributed around the circumference. A sealing gasket is sandwiched in the middle to achieve airtight isolation of the chamber. Existing spring brake cylinders require eight sets of bolts, nuts, and spring washers between the middle and rear housings during operation. This assembly process is complex, consuming significant labor and time. Furthermore, sealing problems often arise due to loose nuts. The middle and front housings are typically connected by clamps and bolts. This requires high quality control of components and precise control of bolt torque, making the process complex and difficult to manage. Summary of the Invention

[0003] The purpose of this invention is to provide a spring brake cylinder in which the rear shell is directly fixed to the front shell, so as to solve the defects of existing spring brake cylinders that are time-consuming and labor-intensive to assemble.

[0004] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a spring brake cylinder with a rear shell directly fixed to a front shell, comprising a spring brake cylinder rear shell; The inner wall of the rear housing of the spring brake cylinder is fitted with a middle housing body, and the inner wall of the rear housing of the spring brake cylinder is fitted with a front housing assembly of the spring brake cylinder. A piston body is movably installed inside the rear housing of the spring brake cylinder. An energy storage spring is provided on one side of the piston body. A Y-shaped sealing ring is installed on the outer wall of the piston body. A piston rod is fixedly connected to the inner wall of the piston body. A release bolt is installed inside the piston rod. A one-way valve is installed at the end of the piston rod. An air inlet is opened inside the middle housing. A gap is provided at the outlet point of the air inlet.

[0005] Preferably, the spring brake cylinder front housing assembly includes a first push plate rod, a first push rod connector, a first return spring, a dust cover, a first front housing fixing edge, fixing bolts, a first diaphragm, and a first inflation chamber. The first push plate rod is fitted with a first push rod connector at its bottom. A dust cover is fitted on the outer wall of the first push rod connector. A first return spring is provided on the outer wall of the dust cover. A first diaphragm is fitted on the outer wall of the first push plate rod. A first inflation chamber is provided between the first diaphragm and the middle housing body.

[0006] Preferably, the spring brake cylinder front housing assembly includes a second push plate rod, a second push rod connector, a nut, a connecting fork, a second return spring, a second front housing fixing edge, a second diaphragm, and a second inflation chamber. The second push plate rod is fitted with a second push rod connector at its bottom, a nut is fitted on the outer wall of the second push rod connector, a connecting fork is provided at the bottom of the nut, a second return spring is provided on the outer wall of the second push rod connector, a second diaphragm is fitted on the outer wall of the second push plate rod, and a second inflation chamber is provided between the second diaphragm and the middle housing body.

[0007] Preferably, the spring brake cylinder front housing assembly includes a third push plate rod, a third push rod connector, a small oil seal assembly, and a third front housing fixed edge. The bottom of the third push plate rod is fixedly connected to the third push rod connector, and the small oil seal assembly is movably connected to the third push rod connector.

[0008] Preferably, the first push rod joint and the front housing form a sliding structure, the first return spring is sleeved and installed on the outer wall of the dust cover, the fixed edge of the first front housing is engaged with the rear housing of the spring brake cylinder, and the fixing bolts are symmetrically arranged along the central axis of the front housing.

[0009] Preferably, the second return spring is sleeved and installed on the outer wall of the second push rod joint, and the fixed edge of the second front shell is engaged with the rear shell of the spring brake cylinder.

[0010] Preferably, the small oil seal assembly is fixedly installed on the inner wall of the front housing, the fixed edge of the third front housing is engaged with the rear housing of the spring brake cylinder, and the third push rod joint and the small oil seal assembly form a sliding structure.

[0011] Preferably, the inner shell body has a through hole, the inner wall of the through hole has an assembly groove, the inner wall of the assembly groove has a positioning slot, the inner shell O-ring is installed inside the assembly groove, and the outer wall of the O-ring is fixedly connected to a positioning block.

[0012] Preferably, the O-ring of the middle shell is engaged with the main body of the middle shell through an assembly groove, and the positioning block is engaged with the main body of the middle shell through a positioning slot.

[0013] Preferably, the inner wall of the O-ring of the middle shell is in contact with the outer wall of the piston rod, and the piston rod forms a sliding structure with the middle shell body through the through hole of the middle shell.

[0014] The present invention provides a spring brake cylinder in which the rear shell and the front shell are directly fixed, which has the following advantages: By assembling a spring brake cylinder with a rear housing, a middle housing, a front housing assembly, a piston body, and a piston rod, and using a piston body made of a high-polymer composite material, the outer edge of the piston body directly engages with the inner cylindrical surface of the rear housing for guidance, eliminating the need for a nylon guide ring between the piston body and the rear housing. Simultaneously, the middle flange of the middle housing directly engages with the outer cylindrical surface of the piston rod for guidance, again eliminating the need for a nylon guide ring between the middle housing and the piston rod. This saves on guide ring parts and corresponding assembly processes, improves assembly efficiency, and reduces costs. Furthermore, the main body of the middle shell is directly press-fitted between the rear shell and the front shell assembly of the spring brake cylinder. There is no need for bolts, nuts, or spring washers to connect the main body of the middle shell to the rear shell of the spring brake cylinder, nor is there a need for a locking screw-on assembly method. This saves a significant number of fasteners, simplifies the assembly process, reduces labor and time costs, and avoids sealing problems caused by loose nuts. Furthermore, the front housing assembly and the rear housing of the spring brake cylinder are preferably fixed together using a rolled edge method, which differs from the existing technology that uses clamps, bolts, and nuts for fixing. The rolled edge structure forms a reliable connection around the entire circumference of the spring brake cylinder housing, ensuring durability and stability. At the same time, it saves on clamps, bolts, nuts, and other parts, improving the reliability of the spring brake cylinder, increasing assembly efficiency, and reducing costs. Furthermore, the piston body and piston rod are injection molded into one piece, directly forming the piston assembly, eliminating the need for riveting or threaded connections between the piston and piston rod as in traditional structures. Simultaneously, the piston rod employs a rolled edge structure, improving the tensile strength of the piston assembly, unlike traditional straight-tube piston rods. The overall assembly process is short and easy to assemble; the spring brake cylinder can be miniaturized in both diameter and overall length, facilitating vehicle layout. The device is equipped with a piston rod, a through hole in the middle shell, an assembly groove, a positioning slot, an O-ring in the middle shell, and positioning blocks. By pressing the O-ring in the middle shell, it is placed in the assembly groove inside the through hole of the middle shell. Releasing the O-ring allows it to return to its original position and lock into the assembly groove due to its elasticity. This causes the positioning blocks at various positions to lock into the corresponding positioning slots for limiting their movement. This facilitates quick assembly and positioning of the O-ring in the middle shell. At the same time, the inner wall of the O-ring in the middle shell is always in contact with the outer wall of the piston rod, further improving the sealing performance when the piston rod slides along the through hole of the middle shell. Attached Figure Description

[0015] Figure 1 This is a cross-sectional view of the disc-type spring brake cylinder of the present invention. Figure 2 This is a cross-sectional view of the drum-type spring brake cylinder of the present invention. Figure 3This is a cross-sectional view of the wedge spring brake cylinder of the present invention; Figure 4 This is a three-dimensional structural diagram of the piston rod of the present invention; Figure 5 This is a partial cross-sectional view of the main body of the middle shell of the present invention; Figure 6 For the present invention Figure 5 Enlarged view of the structure at point A in the middle.

[0016] The reference numerals in the diagram are explained as follows: 1. Rear housing of the spring brake cylinder; 2. Main body of the middle housing; 3. Front housing assembly of the spring brake cylinder; 31. First push plate pull rod; 32. First push rod joint; 33. First return spring; 34. Dust cover; 35. Fixed edge of the first front housing; 36. Fixing bolt; 37. First diaphragm; 38. First inflation chamber; 39. Second push plate pull rod; 310. Second push rod joint; 311. Nut; 312. Connecting fork; 313. Second return spring; 314. Second... 315. Front housing fixed edge; 316. Second diaphragm; 317. Second inflation chamber; 318. Third push plate pull rod; 319. Third push rod joint; 320. Small oil seal assembly; 4. Energy storage spring; 5. Y-type sealing ring; 6. Piston body; 7. Piston rod; 8. Release bolt; 9. One-way valve; 10. Inflation hole; 11. Gap; 12. Middle housing through hole; 13. Assembly groove; 14. Positioning slot; 15. Middle housing O-ring seal; 16. Positioning block. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Please see Figures 1-6 The present invention provides a spring brake cylinder with a rear shell directly fixed to a front shell, comprising a spring brake cylinder rear shell 1.

[0019] Reference Figure 1 , Figure 2 and Figure 3As shown, a middle shell body 2 is installed on the inner wall of the rear shell 1 of the spring brake cylinder, and a front shell assembly 3 of the spring brake cylinder is installed on the inner wall of the rear shell 1. A piston body 6 is movably installed inside the rear shell 1 of the spring brake cylinder. An energy storage spring 4 is provided on one side of the piston body 6. A Y-type sealing ring 5 is installed on the outer wall of the piston body 6. A piston rod 7 is fixedly connected to the inner wall of the piston body 6. A release bolt 8 is installed inside the piston rod 7. A one-way valve 9 is installed at the end of the piston rod 7. An air inlet 10 is opened inside the middle shell body 2. The outlet point of 10 has a gap 11. The spring brake cylinder front housing assembly 3 includes a first push plate rod 31, a first push rod connector 32, a first return spring 33, a dust cover 34, a first front housing fixing edge 35, a fixing bolt 36, a first diaphragm 37, and a first inflation chamber 38. The first push plate rod 31 is equipped with a first push rod connector 32 at its bottom. A dust cover 34 is installed on the outer wall of the first push rod connector 32. The outer wall of the dust cover 34 is provided with a first return spring 33. The outer wall of the first push plate rod 31 is equipped with a first diaphragm 37. A first inflation chamber 38 is provided between the first diaphragm 37 and the middle shell body 2. The spring brake cylinder front shell assembly 3 includes a second push plate rod 39, a second push rod connector 310, a nut 311, a connecting fork 312, a second return spring 313, a second front shell fixing edge 314, a second diaphragm 315, and a second inflation chamber 316. The second push plate rod 39 has a second push rod connector 310 installed at its bottom. A nut 311 is installed on the outer wall of the second push rod connector 310. A connecting fork 312 is provided at the bottom of the nut 311. The outer wall of the rod joint 310 is provided with a second return spring 313, the outer wall of the second push plate rod 39 is provided with a second diaphragm 315, and a second air chamber 316 is provided between the second diaphragm 315 and the middle shell body 2. The spring brake cylinder front shell assembly 3 includes a third push plate rod 317, a third push rod joint 318, a small oil seal assembly 319 and a third front shell fixing edge 320. The bottom of the third push plate rod 317 is fixedly connected to the third push rod joint 318, and the small oil seal assembly 319 is movably connected to the third push rod joint 318.

[0020] When the car starts, compressed air enters the rear inflation chamber (composed of the rear housing 1 of the spring brake cylinder, the middle housing body 2, and the piston body 6) through the inflation port 10. After the compressed air is filled into the rear inflation chamber, the pressure pushes the piston body 6 to overcome the pressure of the energy storage spring 4, causing the piston body 6 to move towards the bottom area of ​​the rear housing 1 of the spring brake cylinder. At this time, the piston rod 7, which is integrated with the piston body 6, moves backward synchronously in the middle housing through hole 12 of the middle housing body 2. In the service brake chamber, the first push plate lever 31 (or the second push plate lever 39, the third push plate lever 317) and the push rod joint connected thereto move backward into the front housing assembly 3 of the spring brake cylinder under the action of the first return spring 33 (or the second return spring 313), thereby releasing the braking element of the braking device and completing the switch from the braking state of the energy storage spring 4 to the released braking state.

[0021] Reference Figure 1 , Figure 2 and Figure 3 As shown, the first push rod joint 32 and the front housing form a sliding structure, the first return spring 33 is sleeved and installed on the outer wall of the dust cover 34, the first front housing fixed edge 35 is engaged with the rear housing 1 of the spring brake cylinder, the fixing bolts 36 are symmetrically arranged along the central axis of the front housing, the second return spring 313 is sleeved and installed on the outer wall of the second push rod joint 310, the second front housing fixed edge 314 is engaged with the rear housing 1 of the spring brake cylinder, the small oil seal assembly 319 is fixedly installed on the inner wall of the front housing, the third front housing fixed edge 320 is engaged with the rear housing 1 of the spring brake cylinder, and the third push rod joint 318 and the small oil seal assembly 319 form a sliding structure.

[0022] With the parking brake released, compressed air is supplied to the first inflation chamber 38 (or the second inflation chamber 316). This compressed air acts on the first diaphragm 37 (or the second diaphragm 315, and related diaphragms in the wedge structure). The diaphragm transmits the gas pressure to the first push plate lever 31 (or the second push plate lever 39, the third push plate lever 317) and the push rod connector, pushing the push plate and push rod assembly forward within the spring brake cylinder front housing assembly 3. The push rod connector ultimately pushes the braking element of the braking device, achieving the service brake. When the service brake is released, the restoring force of the first return spring 33 (or the second return spring 313) resets the push plate and push rod assembly. When the compressed air supply to the vehicle is interrupted or the compressed air pressure in the rear inflation chamber decreases (such as during parking or in the air circuit), the energy storage spring 4 releases its stored energy, pushing the piston body 6 back to its initial position. The piston body 6 drives the piston rod 7 to move forward, and the piston rod 7 pushes the first push plate rod 31 (or the second push plate rod 39, the third push plate rod 317) and the push rod joint to move forward. The push plate and push rod assembly then pushes the braking element to achieve parking brake or emergency brake.

[0023] Reference Figure 4 , Figure 5 and Figure 6 As shown, the inner shell body 2 has a through hole 12, the inner wall of the through hole 12 has an assembly groove 13, the inner wall of the assembly groove 13 has a positioning slot 14, the inner wall of the assembly groove 13 has a middle shell O-ring seal 15 installed inside the assembly groove 13, and the outer wall of the middle shell O-ring seal 15 is fixedly connected to a positioning block 16. The positioning blocks 16 are arranged in a ring array with the central axis of the middle shell O-ring seal 15 as the center. The middle shell O-ring seal 15 is engaged with the middle shell body 2 through the assembly groove 13, and the positioning blocks 16 are engaged with the middle shell body 2 through the positioning slot 14. The inner wall of the middle shell O-ring seal 15 is in contact with the outer wall of the piston rod 7, and the piston rod 7 forms a sliding structure with the middle shell body 2 through the through hole 12.

[0024] By pressing the O-ring 15 of the middle shell, it is placed in the assembly groove 13 inside the through hole 12 of the middle shell. The O-ring 15 of the middle shell is released. Under its own elasticity, the O-ring 15 of the middle shell can be restored and locked into the assembly groove 13. This causes the positioning blocks 16 at each position to be locked into the positioning grooves 14 for limiting, so that the O-ring 15 of the middle shell can be stably installed on the inner wall of the through hole 12 of the middle shell. When the piston rod 7 slides along the through hole 12 of the middle shell, the inner wall of the O-ring 15 of the middle shell is always in contact with the outer wall of the piston rod 7, thus achieving dynamic sealing.

[0025] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A spring brake cylinder with a rear shell directly fixed to a front shell, comprising a spring brake cylinder rear shell (1). Its features are: The inner wall of the rear shell (1) of the spring brake cylinder is fitted with a middle shell body (2), and the inner wall of the rear shell (1) of the spring brake cylinder is fitted with a front shell assembly (3). The piston body (6) is movably installed inside the rear shell (1) of the spring brake cylinder. An energy storage spring (4) is provided on one side of the piston body (6). A Y-shaped sealing ring (5) is installed on the outer wall of the piston body (6). A piston rod (7) is fixedly connected to the inner wall of the piston body (6). A release bolt (8) is installed inside the piston rod (7). A one-way valve (9) is installed at the end of the piston rod (7). An air inlet (10) is opened inside the middle shell body (2). A gap (11) is provided at the outlet point of the air inlet (10).

2. A spring brake cylinder with a rear shell directly fixed to a front shell according to claim 1, characterized in that: The spring brake cylinder front housing assembly (3) includes a first push plate rod (31), a first push rod connector (32), a first return spring (33), a dust cover (34), a first front housing fixing edge (35), a fixing bolt (36), a first diaphragm (37), and a first inflation chamber (38). The first push plate rod (31) is equipped with a first push rod connector (32) at its bottom. The outer wall of the first push rod connector (32) is equipped with a dust cover (34). The outer wall of the dust cover (34) is provided with a first return spring (33). The outer wall of the first push plate rod (31) is equipped with a first diaphragm (37). The first inflation chamber (38) is provided between the first diaphragm (37) and the middle housing body (2).

3. A spring brake cylinder with a rear shell directly fixed to a front shell according to claim 1, characterized in that: The spring brake cylinder front housing assembly (3) includes a second push plate rod (39), a second push rod connector (310), a nut (311), a connecting fork (312), a second return spring (313), a second front housing fixing edge (314), a second diaphragm (315), and a second inflation chamber (316). The second push plate rod (39) is equipped with a second push rod connector (310) at its bottom. The second push rod connector (310) is equipped with a nut (311) on its outer wall. The nut (311) is equipped with a connecting fork (312) at its bottom. The second push rod connector (310) is equipped with a second return spring (313) on its outer wall. The second push plate rod (39) is equipped with a second diaphragm (315) on its outer wall. The second diaphragm (315) is located between the second diaphragm (315) and the middle housing body (2).

4. A spring brake cylinder with a rear shell directly fixed to a front shell according to claim 1, characterized in that: The spring brake cylinder front housing assembly (3) includes a third push plate rod (317), a third push rod connector (318), a small oil seal assembly (319), and a third front housing fixed edge (320). The bottom of the third push plate rod (317) is fixedly connected to the third push rod connector (318), and the small oil seal assembly (319) is movably connected to the third push rod connector (318).

5. A spring brake cylinder with the rear shell and front shell directly fixed according to claim 2, characterized in that: The first push rod joint (32) forms a sliding structure with the front shell housing. The first return spring (33) is sleeved and installed on the outer wall of the dust cover (34). The first front shell fixing edge (35) is engaged with the spring brake cylinder rear shell (1). The fixing bolt (36) is symmetrically arranged on the central axis of the front shell housing.

6. A spring brake cylinder with the rear shell and front shell directly fixed according to claim 3, characterized in that: The second return spring (313) is sleeved and installed on the outer wall of the second push rod joint (310), and the second front shell fixing edge (314) is engaged with the spring brake cylinder rear shell (1).

7. A spring brake cylinder with the rear shell directly fixed to the front shell according to claim 4, characterized in that: The small oil seal assembly (319) is fixedly installed on the inner wall of the front housing. The third front housing fixed edge (320) is engaged with the rear housing (1) of the spring brake cylinder. The third push rod joint (318) and the small oil seal assembly (319) form a sliding structure.

8. A spring brake cylinder with the rear shell and front shell directly fixed according to claim 1, characterized in that: The inner shell body (2) has a through hole (12), the inner wall of the through hole (12) has an assembly groove (13), the inner wall of the assembly groove (13) has a positioning slot (14), the inner wall of the assembly groove (13) has an O-ring (15) installed inside the assembly groove (13), and the outer wall of the O-ring (15) has a positioning block (16) fixedly connected.

9. A spring brake cylinder with the rear shell directly fixed to the front shell according to claim 8, characterized in that: The O-ring seal (15) of the middle shell is engaged with the body (2) of the middle shell through the assembly groove (13), and the positioning block (16) is engaged with the body (2) of the middle shell through the positioning groove (14).

10. A spring brake cylinder with the rear shell and front shell directly fixed according to claim 8, characterized in that: The inner wall of the O-ring (15) of the middle shell is in contact with the outer wall of the piston rod (7), and the piston rod (7) forms a sliding structure with the middle shell body (2) through the middle shell through hole (12).

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