Brake upper pump with reducing oil seal
By combining the variable diameter oil seal structure and the pressure relief valve mechanism, the problem of non-linear feel of the brake pump is solved, achieving rapid filling of brake fluid and effortless braking effect, thus improving the comfort and linearity of braking operation.
Patent Information
- Application Number
- CN202520075610.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-13
- Publication Date
- 2025-11-25
- Estimated Expiration
- 2035-01-13
AI Technical Summary
Most existing brake booster cylinders are single-piston structures, which cannot achieve the effect of having a relatively large oil seal area at the front and a relatively small oil seal area at the rear. This results in non-linear brake feel, which may lead to a hard or unstable feel.
It adopts a differential oil seal structure, including a first oil seal and a second oil seal. The front section has a larger oil seal area and the rear section has a smaller oil seal area. It achieves segmented operation through a pressure relief valve mechanism. The pressure is adjusted by a floating pressure relief valve core and a pressure relief spring to realize the lever arm change between the front and middle sections and the middle and rear sections.
It achieves rapid brake fluid filling and effortless braking, with a large initial fluid displacement and low subsequent pressure, resulting in linear overall motion performance, reducing uneven brake feel and improving braking comfort.
Smart Images
Figure CN223590917U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of oil brake, especially a brake upper pump with different diameter oil seal. BACKGROUND
[0002] The hydraulic brake upper pump (master cylinder) is one of the key components of the hydraulic brake system. It is usually installed near the handlebar, close to the brake handle position. Its main function is to convert the force applied by the rider through the brake handle into hydraulic pressure, thereby starting the entire braking process. The working principle is: when the rider squeezes the brake handle, the force acts on the piston, and the piston moves forward (towards the brake pipeline) in the cylinder body. The piston movement and resistance characteristics: the movement resistance of the upper pump piston also affects the brake feel. The friction between the piston and the cylinder, the elasticity of the sealing element and other factors determine the resistance of the piston movement. If the piston movement resistance is too large, the brake feel will be hard; if the resistance is too small, it may cause unstable handle travel. In addition, the movement of the lower pump piston is also important. When the pressure is transmitted to the lower pump, the lower pump piston pushes the brake pad into contact with the brake disc. The friction characteristics between the brake pad and the brake disc are also fed back to the brake handle. For example, when the brake pad wears to a certain extent, the contact area and friction characteristics with the brake disc change, which will cause the brake feel to change, which may make the feel soft or uneven.
[0003] The ideal brake upper pump, the front section of the piston push, needs to have a relatively large oil seal area, so as to output more brake oil to the brake lower pump under unit movement distance, so that the brake pad can be quickly pushed out and contacted with the brake disc, at this time the brake effect is formally effective; in the rear section of the piston push, at this time the brake pad in the brake lower pump has approached to static (no displacement), according to the Pascal principle (pressure is equal everywhere in a closed liquid, in the case of the same pressure, the force generated in the small area is smaller), a relatively small oil seal area is needed, so that the pressure borne by the piston end is smaller (the pressure here is proportional to the oil seal area), so that the user can more easily push the brake handle, reduce the wall collision feeling, make the feel of the front section and the rear section operation more linear. However, the existing brake upper pump is mostly single piston (oil seal) structure, so it cannot realize the effect that the front section has a relatively large oil seal area and the rear section has a relatively small oil seal area.
[0004] In summary, the present application improves the prior art. SUMMARY
[0005] In order to overcome the above-mentioned shortcomings of the prior art, the utility model provides a brake upper pump with different diameter oil seal.
[0006] The technical scheme for solving the technical problems of the utility model is: a brake upper pump with different diameter oil seal, comprising:
[0007] The brake pump body is provided with a piston cavity and an oil storage cavity, the piston cavity and the oil storage cavity are filled with brake oil, and the oil storage cavity is communicated with the piston cavity through an oil return hole;
[0008] The brake handle is rotatably connected with the brake pump body through a pivoting mechanism, and the brake handle is abutted with the piston mechanism through a rotating pushing mechanism and forms a transmission cooperation;
[0009] The oil pipe assembly is connected to the brake pump body and is communicated with the piston cavity;
[0010] The piston member is internally provided with a pressure relief cavity, the piston member is provided with an oil inlet channel and an oil discharge hole, and the pressure relief cavity is communicated with the outside of the piston member through the oil inlet channel and the oil discharge hole respectively;
[0011] The first oil seal and the second oil seal are both installed on the piston member, wherein the second oil seal is located in front of the first oil seal, and the effective oil pushing area S2 of the second oil seal is smaller than the effective oil pushing area S1 of the first oil seal;
[0012] The reset spring applies an elastic force to the piston member in the rear direction;
[0013] The pressure relief valve mechanism is installed in the pressure relief cavity;
[0014] The piston cavity is provided with at least a large-diameter cavity section, a small-diameter cavity section and a variable-diameter cavity section, wherein the large-diameter cavity section, the variable-diameter cavity section and the small-diameter cavity section are sequentially distributed and communicated from rear to front;
[0015] The oil return hole is arranged on the large-diameter cavity section, so that the large-diameter cavity section is communicated with the oil storage cavity;
[0016] The first oil seal is located in the large-diameter cavity section, and the first oil seal forms a sealing cooperation with the inner wall of the large-diameter cavity section;
[0017] The second oil seal moves with the piston member, when the second oil seal is located in the large-diameter cavity section, there is a gap between the second oil seal and the inner wall of the large-diameter cavity section to form a non-sealing cooperation, and when the second oil seal is located in the small-diameter cavity section, the second oil seal is abutted with the inner wall of the small-diameter cavity section and forms a sealing cooperation.
[0018] In the specific embodiment of the utility model, when the second oil seal is not abutted with the inner wall of the small-diameter cavity section and the first oil seal is located in front of the oil return hole, the user continues to pinch the brake handle, and the first oil seal pushes the brake oil to the oil pipe assembly;
[0019] When the second oil seal abuts against the inner wall of the small-diameter cavity section, the user continues to pinch the brake handle, the second oil seal pushes brake oil in front of the second oil seal to the oil pipe assembly, and the first oil seal pushes brake oil between the first oil seal and the second oil seal to the floating pressure relief valve core through the oil inlet channel.
[0020] Preferably, the pressure relief valve mechanism comprises the floating pressure relief valve core and the pressure relief spring.
[0021] The floating pressure relief valve core is movably arranged in the pressure relief cavity and is located between the oil inlet channel and the oil discharge hole.
[0022] The pressure relief spring is arranged between the floating pressure relief valve core and the inner wall of the pressure relief cavity, and the pressure relief spring acts on the floating pressure relief valve core to make the floating pressure relief valve core have a forward movement trend.
[0023] Preferably, the piston member is composed of the first piston and the second piston which are detachable from each other.
[0024] The pressure relief cavity and the oil discharge hole are arranged on the first piston, and the first piston has a first supporting position for mounting the first oil seal.
[0025] The oil inlet channel is arranged on the second piston, and the second piston has a second supporting position for mounting the second oil seal.
[0026] In some preferred embodiments of the utility model, a piston sleeve is further included, the first piston is at least partially arranged in the piston sleeve, and a limiting portion is protruded on the inner wall of the piston sleeve and can abut against the rear end of the first piston to form a limiting stop cooperation.
[0027] Preferably, a first sealing ring is sleeved on the outer wall of the first piston to form a sealing cooperation between the outer wall of the first piston and the inner wall of the piston sleeve.
[0028] A second sealing ring is sleeved on the outer wall of the floating pressure relief valve core to form a sealing cooperation between the outer wall of the floating pressure relief valve core and the inner wall of the pressure relief cavity.
[0029] A third sealing ring is sleeved on the outer wall of the piston sleeve to form a sealing cooperation between the outer wall of the piston sleeve and the inner wall of the piston cavity.
[0030] Optionally, a limiting hole is formed in the brake pump body, a limiting groove is arranged on the outer wall of the piston sleeve, and a limiting fastener is clamped into the limiting groove after passing through the limiting hole.
[0031] The mounting structure of the pressure relief spring is that the first piston has a first accommodating groove, the rear end of the floating pressure relief valve core has a second accommodating groove, the rear end of the pressure relief spring extends into the first accommodating groove, and the front end of the pressure relief spring extends into the second accommodating groove.
[0032] Preferably, the front end of the first piston has a first abutting end, the middle part of the first piston is provided with a second abutting end, the first abutting end abuts against the second abutting end and forms a transmission fit;
[0033] The rear end of the second piston has an extending end which at least partially enters the pressure relief cavity.
[0034] The utility model has the advantages that:
[0035] I. The double-piston oil seal structure with different diameters is adopted, and the segmented working mode is realized, the front segment has a relatively large oil seal area, and the rear segment has a relatively small oil seal area, so that the initial segment can push more oil, the brake oil can quickly fill some small gaps and the deformation space of elastic components, and the braking effect is achieved more quickly; the pressure applied to the second oil seal in the middle and rear oil path is relatively small, so that the piston member can be moved forward with smaller force, and the pushing force of the piston member in the middle and rear segment and the front and middle segment will not have a large difference, that is, the overall movement performance will be more linear.
[0036] II. According to the action principle of the force arm, the front and middle segment action point of the application is at the first oil seal, and the middle and rear segment action point is on the second oil seal, which belongs to a variable force arm center point, and correspondingly, when the action point changes, the force resistance and the resistance arm will also change. The middle and rear segment has a larger power arm L1 (conventionally, it is cut off at the first oil seal, and in the application, it is cut off at the second oil seal), and at the same time, the resistance arm L2 is smaller, so that when the user pinches the brake handle, only a small force F1 is needed, so that the user can obtain the same braking effect with less effort. BRIEF DESCRIPTION OF DRAWINGS
[0037] Figure 1 It is a structural schematic view of the brake upper pump in the application.
[0038] Figure 2 It is a comparative schematic view of the first oil seal and the second oil seal.
[0039] Figure 3 It is a vertical sectional view of the brake upper pump (the front and middle segment of the piston member movement) in the application and an enlarged view of the local structure.
[0040] Figure 4 It is a vertical sectional view of the brake upper pump (the middle and rear segment of the piston member movement) in the application and an enlarged view of the local structure.
[0041] Figure 5 is the horizontal sectional view of the brake upper pump (the front middle section of the piston member movement) and the enlarged view of the partial structure thereof in the present application.
[0042] Figure 6 is the horizontal sectional view of the brake upper pump (the middle rear section of the piston member movement) and the enlarged view of the partial structure thereof in the present application.
[0043] Figure 7 is the exploded view of the piston mechanism for the brake.
[0044] Figure 8 is the structural comparison schematic diagram of the piston member before and after being pushed out.
[0045] Figure 9 is the comparison sectional view of the pressure relief valve mechanism before and after being in action.
[0046] In the figure: 1, brake pump body; 11, piston cavity; 111, large-diameter cavity section; 112, small-diameter cavity section; 113, variable-diameter cavity section; 12, oil storage cavity; 13, oil return hole; 14, oil seal cavity; 15, limiting hole; 2, brake handle; 21, pivoting mechanism; 22, rotating and pushing mechanism; 3, oil pipe assembly; 4, piston member; 41, first piston; 411, pressure relief cavity; 412, oil discharge hole; 413, first support position; 414, first abutting end; 415, first accommodating groove; 42, second piston; 421, oil inlet channel; 422, second support position; 423, second abutting end; 424, extending end; 43, first oil seal; 44, second oil seal; 45, return spring; 5, floating pressure relief valve core; 51, second accommodating groove; 6, pressure relief spring; 7, piston cylinder sleeve; 71, limiting part; 72, limiting groove; 73, limiting fastener; 81, first sealing ring; 82, second sealing ring; 83, third sealing ring. DETAILED DESCRIPTION
[0047] The present application will be further described below in conjunction with the drawings and specific embodiments. It should be noted that the embodiments are only specific descriptions of the present application, and the purpose is to enable those skilled in the art to better understand the technical solutions of the present application, and should not be regarded as a limitation on the present application.
[0048] In the description of the present application, it should be noted that if the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.
[0049] In the description of the utility model, it is to explain that, unless there is explicit stipulation and limitation, such as the term "installation", "connection", "connection" should be understood in a broad sense, for example, it can be fixed connection, can also be detachable connection, or integrally connected; can be mechanical connection, can also be electrical connection; can be direct connection, can also be indirectly connected through the intermediate medium, can be the communication inside two elements. For the person skilled in the art, the specific meaning of the above-mentioned terms in the utility model can be understood according to the specific circumstances.
[0050] Example one
[0051] Refer to Figures 1-9The brake upper pump with the different-diameter oil seal comprises a brake pump body 1, a brake handle 2, an oil pipe assembly 3 and a piston member 4. The brake pump body 1 is provided with a piston cavity 11 and an oil storage cavity 12, and the piston cavity 11 and the oil storage cavity 12 are filled with brake oil. The oil storage cavity 12 is communicated with the piston cavity 11 through an oil return hole 13. The brake handle 2 is rotatably connected with the brake pump body 1 through a pivoting mechanism 21, and the brake handle 2 is abutted with the piston member 4 through a rotating and pushing mechanism 22 and is in transmission cooperation with the piston member 4. The oil pipe assembly 3 is connected with the brake pump body 1 and is communicated with the piston cavity 11. The oil pipe assembly 3 can be extended and communicated with a brake lower pump, so that the brake upper pump and the brake lower pump form a complete brake oil circuit. The piston member 4 is internally provided with a pressure relief cavity 411. The piston member 4 is provided with an oil inlet channel 421 and an oil discharge hole 412. The pressure relief cavity 411 is communicated with the outside of the piston member 4 through the oil inlet channel 421 and the oil discharge hole 412. Brake oil can flow between the inside of the pressure relief cavity 411 and the outside of the pressure relief cavity 411 (generally referring to the piston cavity 11) through the oil inlet channel 421 and the oil discharge hole 412. The flow direction of the brake oil is determined according to the internal and external pressure of the pressure relief cavity 411, and is not specially limited. A first oil seal 43 and a second oil seal 44 are both installed on the piston member 4. The second oil seal 44 is located at the front side of the first oil seal 43, and the effective oil pushing area S2 of the second oil seal 44 is smaller than the effective oil pushing area S1 of the first oil seal 43. Preferably, the piston member 4 is composed of a first piston 41 and a second piston 42 which are detachable from each other (after assembly, the two are integrated and move forward or backward synchronously). The pressure relief cavity 411 and the oil discharge hole 412 are arranged on the first piston 41, and the first piston 41 is provided with a first supporting position 413 for installing the first oil seal 43. The oil inlet channel 421 is arranged on the second piston 42, and the second piston 42 is provided with a second supporting position 422 for installing the second oil seal 44. When the piston member 4 moves, the first oil seal 43 and the second oil seal 44 are driven to move forward, so that the brake oil is pushed forward by the first oil seal 43 and / or the second oil seal 44. A reset spring 45 applies an elastic force to the piston member 4 in the backward direction, so that the piston member 4 always has a backward reset movement tendency. When the user releases the brake handle 2, the piston member 4 is automatically reset in the backward direction under the action of the reset spring 45 and the oil pressure. It should be noted that when the first oil seal 43 moves in the space between the initial position and the oil return hole 13, the first oil seal 43 advances to push the brake oil from the piston cavity 11 to the oil storage cavity 12 through the oil return hole 13 (i.e. the brake oil does not flow to the brake lower pump), so that the brake does not work during this process. This section is also called an idle stroke section.
[0052] It needs to be particularly emphasized that the pressure relief valve mechanism is installed in the pressure relief cavity 411. Corresponding structure is that the piston cavity 11 has at least a large-diameter cavity section 111, a small-diameter cavity section 112 and a variable-diameter cavity section 113, wherein the large-diameter cavity section 111, the variable-diameter cavity section 113 and the small-diameter cavity section 112 are sequentially distributed from back to front and are communicated; wherein the oil return hole 13 is arranged on the large-diameter cavity section 111, so that the large-diameter cavity section 111 is communicated with the oil storage cavity 12; the first oil seal 43 is located in the large-diameter cavity section 111, and the first oil seal 43 forms a sealing fit with the inner wall of the large-diameter cavity section 111. The second oil seal 44 moves with the piston member 4; when the second oil seal 44 is located in the large-diameter cavity section 111, there is a gap between the second oil seal 44 and the inner wall of the large-diameter cavity section 111 to form a non-sealing fit; when the second oil seal 44 is located in the small-diameter cavity section 112, the second oil seal 44 abuts against the inner wall of the small-diameter cavity section 112 and forms a sealing fit.
[0053] The specific composition scheme of the pressure relief valve is preferably: the pressure relief valve mechanism includes a floating pressure relief valve core 5 and a pressure relief spring 6; wherein the floating pressure relief valve core 5 is movably arranged in the pressure relief cavity 411, and the floating pressure relief valve core 5 is located between the oil inlet channel 421 and the oil discharge hole 412; the pressure relief spring 6 is abutted between the floating pressure relief valve core 5 and the inner wall of the pressure relief cavity 411, and the pressure relief spring 6 acts on the floating pressure relief valve core 5, so that the floating pressure relief valve core 5 has a movement tendency of moving forward.
[0054] The working mechanism of the pressure relief valve mechanism is:
[0055] When the second oil seal 44 is not abutted against the inner wall of the small-diameter cavity section 112 and the first oil seal 43 is located in front of the oil return hole 13, the user continues to pinch the brake handle 2, the first oil seal 43 pushes the brake oil out of the oil pipe assembly 3, and at this time the pressure relief valve does not have pressure relief effect;
[0056] When the second oil seal 44 abuts against the inner wall of the small-diameter cavity section 112, a relatively closed oil seal cavity 14 is formed between the first oil seal 43 and the second oil seal 44, the oil seal cavity 14 is isolated from the front side of the second oil seal 44, and the user continues to pinch the brake handle 2, the second oil seal 44 pushes the brake oil in front of the second oil seal 44 to the oil pipe assembly 3, and the first oil seal 43 pushes the brake oil between the first oil seal 43 and the second oil seal 44 to the floating pressure relief valve core 5 through the oil inlet channel 421, the floating pressure relief valve core 5 retreats under pressure, the pressure relief spring 6 is contracted to store energy, and at the same time, the brake oil in the pressure relief cavity 411 itself flows to the piston cavity 11 through the oil drain hole 412, that is, the floating pressure relief valve core 5 is supplied with oil on the front side and drained on the back side, and relative pressure balance is achieved, so that the pressure relief valve mechanism plays an effective pressure relief role, and prevents the pressure between the first oil seal 43 and the second oil seal 44 from being too large to affect normal use.
[0057] In summary, the main advantage of the utility model lies in that the double-piston oil seal structure with different diameters is adopted, and a segmented working mode is realized, so that the front section has a relatively large oil seal area, and the rear section has a relatively small oil seal area. Specifically, the front and middle section first oil seal 43 performs actual oil pushing work, and the characteristic is that the effective oil pushing area S1 of the first oil seal 43 is larger, so that in the application of the oil pressure brake, the initial oil pushing amount is larger, the brake oil quickly fills some small gaps and elastic component deformation spaces, and the braking effect is more rapid; the middle and rear section second oil seal 44 performs actual oil pushing work, and the characteristic is that the effective oil pushing area S2 of the second oil seal 44 is smaller, according to the Pascal principle (pressure is equal everywhere in a closed liquid, and in the case of the same pressure, the force generated in a small area is smaller), so that the pressure applied to the second oil seal 44 in the oil way is relatively small, and therefore the piston member 4 can be pushed forward with smaller force, so that the pushing force of the piston member 4 in the middle and rear section and the front and middle section will not have a large gap, that is, the overall movement performance will be more linear. Moreover, during the middle and rear section process, the pressure between the first oil seal 43 and the second oil seal 44 can be relieved through the floating pressure relief valve core 5, so that the oil pushing of the first oil seal 43 hardly affects the second oil seal 44.
[0058] Another key advantage is that, according to the principle of the force arm (formula F1*L1=F2*L2, when you hold the brake handle 2 to apply force, the length of the force arm will affect the size of the force required. Among them, when the power arm (brake handle 2 force arm) is longer, under the condition of certain resistance and resistance arm, the required power (the force you exert on the brake handle 2) is smaller, which is the principle of labor saving). Therefore, the front middle segment of the application acts on the first oil seal 43, and the middle rear segment acts on the second oil seal 44, which belongs to the variable center point of the force arm. Correspondingly, when the action point changes, the resistance of the force and the resistance arm will also change. In particular, the middle rear segment has a larger power arm L1 (conventionally, it is cut off at the first oil seal 43, and the application is cut off at the second oil seal 44), and the resistance arm L2 is smaller, so that when the user pinches the brake handle 2, only a small force F1 is required, making it more labor-saving for the user to obtain the same braking effect.
[0059] Embodiment two
[0060] On the basis of the structure of embodiment one, this embodiment provides a more preferred structure scheme for part of the structure, specifically:
[0061] I. Refer to Figures 7-9 , adopt the structure scheme of split piston assembly (first piston 41 and second piston 42), on the one hand, it is easier to process and manufacture, reducing production cost; on the other hand, it provides more operating space for the assembly of floating type pressure relief valve core 5, pressure relief spring 6 and other parts, reduces the difficulty of assembly process, and improves production efficiency. Of course, the split piston assembly structure is only a preferred scheme, and the piston member 4 can also adopt an integrated structure, which is not specially limited here.
[0062] Optionally, the front end of the first piston 41 has a first abutting end 414, the middle part of the first piston 41 is provided with a second abutting end 423, the first abutting end 414 abuts with the second abutting end 423 and forms a transmission cooperation. Through the setting of the two abutting ends, the front end of the first piston 41 and the second piston 42 can form a larger contact area, thereby ensuring more stable force transmission effect. On the other hand, the rear end of the second piston 42 has a protruding end 424, which at least partially enters the pressure relief chamber 411, and plays a certain limiting and guiding role to prevent the second piston 42 from moving in the non-front and rear direction relative to the first piston 41.
[0063] Optionally, a limiting hole 15 is formed on the brake pump body 1, a limiting groove 72 is provided on the outer wall of the piston cylinder sleeve 7, and a limiting fastener 73 is clamped into the limiting groove 72 after passing through the limiting hole 15. Through the action of the limiting fastener 73 (generally a screw), the piston cylinder sleeve 7 and the brake pump body 1 form a relatively stable connection and positional relationship.
[0064] II. Refer to Figures 3-6 The first piston 41 is at least partially arranged in the piston sleeve 7, and a limiting portion 71 is protruded on the inner wall of the piston sleeve 7, which can abut against the rear end of the first piston 41 and form a limiting stop cooperation. The piston sleeve 7 is arranged mainly to play a role of supporting, limiting protection and movement guiding of the piston member 4. On the other hand, the rotating pushing mechanism 22 can partially extend into the piston sleeve 7 and abut against the first piston 41, so as to realize the transmission cooperation of the rotating pushing mechanism 22 and the piston member 4 (the first piston 41).
[0065] Preferably, in order to constrain the deformation process of the pressure relief spring 6 and prevent unnecessary deformation of the pressure relief spring 6, the following structure is adopted: the first piston 41 has a first accommodating groove 415, the rear end of the floating pressure relief valve core 5 has a second accommodating groove 51, the rear end of the pressure relief spring 6 extends into the first accommodating groove 415, and the front end of the pressure relief spring 6 extends into the second accommodating groove 51. Through the arrangement of the first accommodating groove 415 and the second accommodating groove 51, the two ends of the pressure relief spring 6 are effectively limited, so that the pressure relief spring 6 can be more stably used in cooperation with the floating pressure relief valve core 5.
[0066] III. Sealing structure: refer to Figures 3-7 A first sealing ring 81 is sleeved on the outer wall of the first piston 41, so that the outer wall of the first piston 41 and the inner wall of the piston sleeve 7 form a sealing cooperation; a second sealing ring 82 is sleeved on the outer wall of the floating pressure relief valve core 5, so that the outer wall of the floating pressure relief valve core 5 and the inner wall of the pressure relief cavity 411 form a sealing cooperation; and a third sealing ring 83 is sleeved on the outer wall of the piston sleeve 7, so that the outer wall of the piston sleeve 7 and the inner wall of the piston cavity 11 form a sealing cooperation. Through the arrangement of the plurality of sealing rings, the gaps between the related parts are filled, so as to ensure good sealing cooperation, prevent oil leakage and stabilize the internal pressure.
[0067] It should be pointed out that other technical solutions of the utility model belong to the prior art, and therefore are not described in detail.
[0068] The above description is only the preferred embodiments of the utility model, and it should be pointed out that, for ordinary skilled persons in the art, without departing from the concept of the utility model, a number of improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the utility model.
Claims
1. A brake on pump having a reducer oil seal, characterized by, The utility model relates to a brake pump body (1) is provided with piston cavity (11) and oil storage cavity (12), piston cavity (11) and oil storage cavity (12) are filled with brake oil, and oil storage cavity (12) is communicated with piston cavity (11) through oil return hole (13), brake handle (2) is rotatably connected with brake pump body (1) through pivot mechanism (21), and brake handle (2) is connected with piston mechanism through rotation and push mechanism (22) and forms transmission cooperation, oil pipe assembly (3) is connected with brake pump body (1) and is communicated with piston cavity (11), piston member (4) is provided with pressure relief cavity (411) in the inside, and piston member (4) is provided with oil inlet channel (421) and oil discharge hole (412), and pressure relief cavity (411) is communicated with the outside of piston member (4) through oil inlet channel (421) and oil discharge hole (412) respectively, first oil seal (43) and second oil seal (44) are installed on piston member (4), and second oil seal (44) is located in the front side of first oil seal (43), and the effective oil pushing area S2 of second oil seal (44) is less than the effective oil pushing area S1 of first oil seal (43), reset spring (45) is applied to the elastic force of piston member (4) to the back, pressure relief valve mechanism is installed in pressure relief cavity (411), piston cavity (11) at least has major diameter cavity section (111), minor diameter cavity section (112) and variable diameter cavity section (113), wherein major diameter cavity section (111), variable diameter cavity section (113), minor diameter cavity section (112) are sequentially distributed and communicated from back to front, oil return hole (13) is arranged in major diameter cavity section (111) to make major diameter cavity section (111) communicated with oil storage cavity (12), first oil seal (43) is located in major diameter cavity section (111), and first oil seal (43) forms sealed cooperation with the inner wall of major diameter cavity section (111), second oil seal (44) moves along with piston member (4), when second oil seal (44) is located in major diameter cavity section (111), there is gap between second oil seal (44) and the inner wall of major diameter cavity section (111) to form non-sealed cooperation, when second oil seal (44) is located in minor diameter cavity section (112), second oil seal (44) forms sealed cooperation with the inner wall of minor diameter cavity section (112), when second oil seal (44) is not in contact with the inner wall of minor diameter cavity section (112) and first oil seal (43) is located in front of oil return hole (13), the user continues to pinch brake handle (2), and first oil seal (43) pushes brake oil to oil pipe assembly (3). 2. The brake on pump having a stepped oil seal as claimed in claim 1 wherein: When the second oil seal (44) abuts against the inner wall of the small-diameter cavity section (112), the user continues to pinch the brake handle (2), the second oil seal (44) pushes the brake oil in front of the second oil seal (44) to the oil pipe assembly (3), and the first oil seal (43) pushes the brake oil between the first oil seal (43) and the second oil seal (44) to the floating pressure relief valve core (5) through the oil inlet channel (421).
3. A brake over pump having a step oil seal as claimed in claim 1 or 2 wherein: The pressure relief valve mechanism comprises a floating pressure relief valve core (5) and a pressure relief spring (6); The floating pressure relief valve core (5) is movably arranged in the pressure relief cavity (411), and the floating pressure relief valve core (5) is located between the oil inlet channel (421) and the oil discharge hole (412). The pressure relief spring (6) is arranged between the floating pressure relief valve core (5) and the inner wall of the pressure relief cavity (411), and the pressure relief spring (6) acts on the floating pressure relief valve core (5) to make the floating pressure relief valve core (5) have a forward movement trend.
4. The brake over pump having a step oil seal as set forth in claim 3, wherein: The piston member (4) is composed of a first piston (41) and a second piston (42) which can be disassembled from each other. The pressure relief cavity (411) and the oil discharge hole (412) are arranged on the first piston (41), and the first piston (41) has a first support position (413) for mounting the first oil seal (43). The oil inlet channel (421) is arranged on the second piston (42), and the second piston (42) has a second support position (422) for mounting the second oil seal (44).
5. The brake over pump having a stepped oil seal as set forth in claim 4, wherein: Further comprising a piston sleeve (7), the first piston (41) is at least partially arranged in the piston sleeve (7), and a limiting portion (71) is protruded on the inner wall of the piston sleeve (7), the limiting portion (71) can abut against the rear end of the first piston (41) and form a limiting stop cooperation.
6. The brake over pump having a stepped oil seal as set forth in claim 5, wherein: A first sealing ring (81) is sleeved on the outer wall of the first piston (41) to form a sealing cooperation between the outer wall of the first piston (41) and the inner wall of the piston sleeve (7). A second sealing ring (82) is sleeved on the outer wall of the floating pressure relief valve core (5) to form a sealing cooperation between the outer wall of the floating pressure relief valve core (5) and the inner wall of the pressure relief cavity (411). A third sealing ring (83) is sleeved on the outer wall of the piston sleeve (7) to form a sealing cooperation between the outer wall of the piston sleeve (7) and the inner wall of the piston cavity (11).
7. The brake over pump having a stepped oil seal as set forth in claim 5, wherein: A limiting hole (15) is arranged on the brake pump body (1), a limiting groove (72) is arranged on the outer wall of the piston sleeve (7), and a limiting fastener (73) is inserted into the limiting groove (72) after passing through the limiting hole (15).
8. The brake over pump having a stepped oil seal as set forth in claim 4, wherein: The first piston (41) has a first accommodating groove (415), the rear end of the floating pressure relief valve core (5) has a second accommodating groove (51), the rear end of the pressure relief spring (6) is inserted into the first accommodating groove (415), and the front end of the pressure relief spring (6) is inserted into the second accommodating groove (51).
9. The brake over pump having a stepped oil seal as set forth in claim 4, wherein: The front end of the first piston (41) has a first abutting end (414), the middle part of the first piston (41) is provided with a second abutting end (423), the first abutting end (414) and the second abutting end (423) abut and form a transmission fit; The rear end of the second piston (42) has a protruding end (424) which at least partially enters into the pressure relief cavity (411).