KR200281987Y1 - Car master cylinder - Google Patents

Abstract

The present invention relates to a vehicle master cylinder, the purpose of which is to connect the push rod, the first piston, the second piston of the booster to the first piston and the second piston by the return spring of the booster is installed for the vehicle master cylinder To provide. The present invention provides a ring groove recessed in the circumferential direction in the inner circumferential direction of the opening groove of the first piston so that the first piston can be returned by the return spring provided in the booster, and a fastening ring provided so as to be inserted into the ring groove and expanded. An insertion part provided as an ellipse sphere is provided at the outer end of the push rod of the booster so as to be inserted while extending the fastening ring and fixed to the opening groove as the original restoration of the fastening ring, and connects the push rod and the first piston. A fixing hole opened on the side facing the second piston of the retainer and a plurality of fixing jaws symmetrically protruding from each other toward the center of the fixing hole so as to be interlocked and returned due to the return. Retaining of the second piston so that the fixing jaw can be inserted between the plurality of engaging projections formed to correspond to the fixing holes and the engaging projections A retaining surface facing you connects the retainer and the second piston, and does not use a separate spring for returning the second piston to ensure the required length and the minimum length when the spring is compressed. There is an advantage that you can eliminate the length.

Description

Car master cylinder

The present invention relates to a vehicle master cylinder, and more specifically, a second piston by connecting the push rod, the first piston, and the second piston of the booster so that the first piston and the second piston can be restored by the return spring of the booster. It relates to a vehicle master cylinder is removed a separate spring for returning.

In general, the master cylinder is operated in connection with a booster that amplifies this force when the driver steps on the brake pedal installed in the driver's seat of the vehicle, and is connected to the brakes installed on each wheel to transmit hydraulic pressure.

1 is a cross-sectional view showing a conventional master cylinder. First, the cylinder body 20 forming the external appearance of the master cylinder 10 has a rear side opening so that the push rod 11 of the booster (not shown) can be inserted, and an upper and rear oil supply pipes ( 25) is provided and supplied with oil. In addition, a first piston 30 is installed inside the cylinder body 20 to be connected to the push rod 11 to the booster (not shown), and the first spring 30 is located in front of the first piston 30. 31), the second piston 40, and the second spring 41 is provided.

Next, a first hydraulic chamber 21 is provided between the first piston 30 and the second piston 40, and the first hydraulic chamber 21 is connected to a rear wheel cylinder (not shown). 1 discharge pipe 23 is installed. A second hydraulic chamber 22 is formed between the second piston 40 and the front side of the closed cylinder body 20, and the second hydraulic chamber 22 has a front wheel side wheel cylinder (not shown). A second discharge pipe 24 to be connected is provided.

In addition, the first piston 30 is provided with an opening groove 32 which is opened to the push rod 11 side therein, the push rod 11 is inserted therein so that each other at the time of the advance of the push rod 11 Close contact. The first sealing member 33 is installed at the front and rear of the outer circumferential surface, and the cutoff hole 26 and the supplementary hole communicating with the rear side oil supply pipe 25 at the front and rear of the first sealing member 33 at the front side ( 27) is prepared.

In addition, the second sealing member 45 is installed in the front and rear of the outer circumferential surface of the second piston 40, the sliding hole 42 of the long hole is provided in the middle, the cylinder body ( 20, a stop pin 43 fixed to the upper and lower sides is provided. In addition, a supply hole 28 communicating with the front side oil supply pipe 25 is provided above the sliding hole 42, and a second hydraulic chamber () is provided on the front side of the sliding hole 42 by a stop pin 43. The center valve 44 for opening and closing the oil flow into the 22 is provided.

Meanwhile, a first spring 31 is installed between the first piston 30 and the second piston 40. A retainer 50 is provided at the front side of the first spring 31, and at the rear side. The fixed plate 60 is provided. The retainer 50 is formed to protrude toward the first piston 30, the inside of which is hollow, and the outer periphery thereof extends in a flange shape.

In addition, the fixing plate 60 supports the first spring 31, and is fixed therebetween when the stem 70 and the first piston 30 are coupled to each other. And the stem 70 is inserted into the head portion 72 inserted into the retainer hole 51 formed in the retainer 50 and the screw groove 34 formed in the front side of the first piston 30, the screw portion fixed It consists of 71.

In the conventional master cylinder 10 configured as described above, when the push rod 11 pushes the first piston 30 of the master cylinder 10, the first piston 30 and the second piston 40 are moved forward to be made. Hydraulic pressure is generated in the first hydraulic chamber 21 and the second hydraulic chamber 22. The hydraulic pressure is supplied to the wheel cylinders (not shown) on the front wheel and the rear wheel side through the first discharge pipe 23 and the second discharge pipe 24 to operate a brake (not shown). When the master cylinder 10 is released, the push rod 11, the first piston 30, and the second piston 40 are returned by springs (not shown) 31 and 41, respectively. That is, the push rod 11, the first piston 30, and the second piston 40 are in close contact with each other during operation, but the restoring force of the springs (not shown) 31 and 41 respectively provided when returning to the initial position. Is returned by

However, in the conventional master cylinder configured as described above, the length of the mounting space must be guaranteed to be longer than a certain length in order to secure durability according to the repeated operation of the spring and secure the minimum length when compressed. That is, when the length of the hydraulic chamber in which the spring is installed is short, the compression ratio of the spring installed therein is increased, and the elastic force of the spring decreases when the spring is repeatedly operated. To this end, in order to give the spring proper durability and to secure the minimum length when the spring is compressed, the length of the hydraulic chamber is increased so that the total length of the master cylinder is long. This increases the material cost compared to the master cylinder of short length under the same conditions, which is disadvantageous in processing and the like. In addition, there is a problem that the installation is difficult because of interference with the peripheral parts when installing the engine room of the master cylinder.

The present invention is to solve such a problem, the purpose of the present invention is to connect the push rod, the first piston, the second piston of the booster to restore the first piston and the second piston by the return spring of the booster It is to provide a vehicle master cylinder.

1 is a side cross-sectional view of a conventional master cylinder.

Figure 2 is a side sectional view showing a master cylinder and a booster according to the present invention.

3 is an exploded perspective view showing a push rod and a first piston according to the present invention.

Figure 4 is an exploded perspective view showing a second piston and a retainer according to the present invention.

Explanation of symbols on the main parts of the drawings

116: return spring 120: push rod 121: insertion part

150: cylinder body 160: first piston 165: opening groove

166: ring groove 167: fastening ring 170: second piston

175: hung side 176: hung tube 177: hung projection

180: stem 190: retainer 192: fixing hall

193: support jaw 194: fixed jaw

The present invention for achieving the above object, the reciprocating push rod and the booster is provided with a return spring to return the push rod, coupled with the booster and one side is opened so that one end of the push rod can be inserted The cylinder body, which is provided to be slidable inside the cylinder body, is fixed to protrude toward the first piston having an opening groove in which one side of the push rod is inserted, and a forward movement side of the first piston, and having a head at the protruding end thereof. Retained stem, the retainer is inserted into the inner slide and the retainer hole is provided so that it can be pulled by the head during the backward movement of the first piston, is installed in close contact with the retainer is generated by the forward movement of the first piston Vehicles equipped with a second piston to be moved forward by the hydraulic pressure In the cylinder, a ring groove formed in the recess groove formed in the circumferential direction on the inner surface of the opening groove so that the first piston can be returned by the return spring, and a fastening ring provided to be inserted into the ring groove and expandable. It is inserted into the expansion and is provided with an inserting portion provided as a sphere of the ellipse on one side of the push rod to be fixed to the opening groove in the original restoration of the fastening ring to connect the push rod and the first piston, the first piston A plurality of fixing jaws symmetrically protruding from each other toward the center of the fixing hole and the fixing hole opened on the side facing the second piston of the retainer so as to be interlocked and returned due to the return of the fixing jaw. Between the locking projection and the plurality of locking projections formed to correspond to the fixing hole so that the Is the engaging surface facing the retainer of the second piston provided to jeongteok may be inserted characterized in that the retainer and the second piston is connected.

Hereinafter, with reference to the accompanying drawings will be described embodiments of the present invention;

Figure 2 is a side cross-sectional view showing a master cylinder and a booster according to the present invention, Figure 3 is an exploded perspective view showing a connection structure of the push rod and the first piston according to the present invention. And Figure 4 is an exploded perspective view showing a connection structure of the second piston and the retainer according to the present invention. As shown in the drawing, a booster 110 for amplifying a force applied by a driver is connected to the rear side of the vehicle master cylinder of the present invention, and an oil tank 130 for supplying oil to the inside of the master cylinder 140. Is installed.

First, the booster 110 divides the inner space of the sealed case 111 to form a positive pressure chamber 112 and a transformer chamber 113, and inflow of air into the open center of the rear side. The valve body 115 to control the opening and closing of the transformer chamber 113, and the pedal shaft 117 linked by the brake pedal (not shown), and thus one end of the diaphragm 114 to receive the displacement force Is coupled, the other end is provided with a push rod 120 is connected to the master cylinder 140. In addition, a return spring 116 is provided between the front inner surface and the diaphragm 114 to return the push rod 120 and the diaphragm 114. The booster 110 maintains the positive pressure chamber 112 and the transformer chamber 113 in a vacuum state when not in operation, and external air passes through the valve body 115 when the brake pedal (not shown) is pressed. The differential pressure between the positive pressure chamber 112 and the transformer chamber 113 is generated while flowing into the 113. As a result, the operable diaphragm 114 is pushed toward the positive pressure chamber 112 and the push rod 120 is advanced toward the master cylinder 140 by a force amplified by the force applied by the driver to the pedal shaft 117. When the force applied to the pedal shaft 117 is released, the push rod 120 and the diaphragm 114 are returned to their original state by the return spring 116.

Next, the master cylinder 140 is provided with a cylinder body 150 in which the rear side is opened so that the push rod 120 of the booster 110 protruding to the outside may be inserted to be in close contact with the booster 110. . The upper side of the cylinder body 150 is provided with an oil supply pipe 158 forward and rearward to receive oil from the oil tank 130. In addition, a first piston 160 installed at the booster 110 side and connected to the push rod 120 is installed inside the cylinder body 150, and a first spring 161 is provided at the front of the first piston 160. ) Is provided. Moreover, the stem 180, the retainer 190, and the 2nd piston 170 are provided in the front.

In addition, a first discharge pipe 153 connected to a rear wheel cylinder (not shown) is provided in the first hydraulic chamber 151 provided between the first piston 160 and the second piston 170. A second discharge pipe 156 connected to the front wheel side wheel cylinder (not shown) is provided in the second hydraulic chamber 152 formed between the two pistons 170 and the front side of the closed cylinder body 150. The first sealing member 162 is installed at the front and rear outer circumferential sides of the first piston 160, and the cutoff hole communicating with the rear oil supply pipe 158 at the front and rear of the first sealing member 162 on the front side ( 154 and a supplementary hole 155 are provided. In addition, the second sealing member 171 is installed on the outer circumferential side of the front and rear of the second piston 170, the sliding hole 172 of the long hole which is penetrated to the upper and lower sides is provided in the middle of the second piston 170, A stop pin 173 penetrating the sliding hole 172 is installed in the sliding hole 172 to be fixed to the upper and lower sides of the cylinder body 150. The upper side of the sliding hole 172 is provided with a supply hole 157 in communication with the front side oil supply pipe 158, the sliding hole 172 through the supply hole 157 to the front side of the sliding hole 172. A center valve 174 is provided to open and close the oil supplied to the side into the second hydraulic chamber 152.

Meanwhile, in the present invention, the push rod 120 and the first piston of the booster 110 may return the first piston 160 and the second piston 170 to the return spring 116 provided in the booster 110. 160, and the second piston 170 is connected and installed, the connection structure of the push rod 120 and the first piston 160 is as follows.

First, the ring groove 166 is a circular groove which is recessed to the outer circumferential surface side of the inlet inner circumferential surface of the opening groove 165 opened to the push rod 120 side in the first piston 160, the cross section of which is provided as a rectangle. The outer side of the opening groove 165 in which the ring groove 166 is formed is chamfered to facilitate the insertion of the insertion and detaching part 121 to be described later. In addition, a coupling ring 167 is inserted into the ring groove 166, and the coupling ring 167 is a C-shaped ring whose one side is broken, and is provided to be reduced and expanded in and out.

Next, the insertion part 121 is provided at the tip of the push rod 120. The insertion part 121 is inserted into the opening groove 165 of the first piston 160 and is provided as an elliptic sphere to be fixed by the fastening ring 167. The diameter of the front end is extended to the rear side. A streamlined insertion surface 121a is provided, and at the rear side of the insertion surface 121a, the boundary surface 121b having the largest diameter is provided at the insertion and detaching portion 121, and the insertion surface (at the rear side of the boundary surface 121b). Rather than expanding the diameter of 121a, a fixed surface 121c is formed which is rapidly reduced in diameter. That is, the insertion part 121 is composed of the insertion surface 121a, the boundary surface 121b, and the fixing surface 121c from the front side to the rear side, and the diameter is extended to the rear side to form a vertex at the boundary surface 121b and the boundary surface ( 121b) to form an asymmetrical oval that is rapidly reduced in diameter to the rear side.

In addition, the ring groove 166, the inserting portion 121, and the fastening ring 167 is provided to have a correlation with each other, the inner diameter of the ring groove 166 is the boundary diameter 121b which is the maximum diameter of the inserting portion 121. It is provided with a diameter slightly larger than this so that it can be moved by sliding. The outer diameter should be larger than the size when the fastening ring 167 is positioned at the boundary surface 121b and the fastening ring 167 is fully extended. In addition, the inner diameter of the fastening ring 167 should be smaller than the outer diameter of the boundary surface 121b so as to be in close contact with the fixed surface 121c, and the outer diameter of the fastening ring 167 should be in close contact with the fixed surface 121c. It should be provided so that it can be caught inside the ring groove 166.

In addition, a retainer 190 and a stem 180 are provided between the first piston 160 and the second piston 170. The retainer 190 is installed in combination with the second piston 170, and the stem ( 180 is coupled to the first piston 160. The stem 180 is provided to pull the retainer 190 upon return of the first piston 160.

First, a screw groove 163 recessed inward is provided at a central portion of the front side of the first piston 160. The screw groove 163 is provided with a stem 180 provided with a bolt-shaped long rod to be extended to the second piston 170 side, the stem 180 has a screw portion 182, one end of which is inserted into the screw groove 163. ) Is provided, and a head 181 is provided at the other end positioned toward the second piston 170. And the middle of the screw portion 182 and the head 181 is provided with a larger diameter than the screw portion 182 is formed with a step between the screw portion 182. In addition, a fixing plate 164 supporting the first spring 161 to the rear side is provided between the stem 180 and the first piston 160. The fixing plate 164 is provided so that the center side thereof can be penetrated by the threaded portion 182 so that the stem 182 of the stem 180 is fastened to the threaded groove 163 of the first piston 160. By the step of 180 is in close contact with the first piston 160 side is fixed.

Next, the retainer 190 is a cylindrical hollow tube which is coupled to be interlocked with the second piston 170, and the side facing the second piston 170 is opened to provide the fixing hole 192, and the first piston ( The side facing 160 is closed and its diameter is reduced from the opened side to the closed side to have a tapered shape. A retainer hole 191 is provided at the center of the closed side to allow the stem 180 to slide. In addition, a support jaw 193 extending to the outside and supporting the front of the first spring 161 is provided on the open side outer circumferential surface of the retainer 190 in which the fixing hole 192 is provided. The support jaw 193 is provided in a flange shape, and is provided in three places so as to be symmetrical to each other, and is spaced apart from each support jaw 193 by the same circumferential length as the support jaw 193. That is, three parts protrude symmetrically from each other by dividing the portion extended to the outer circumferential side at the same angle, and three places are symmetrically recessed in between.

In addition, a fixing jaw 194 is provided inside the support jaw 193. The fixing jaw 194 protrudes toward the center so as to alternate with the spaced apart portions of the supporting jaw 193 on the inner circumferential surface of the fixing hole 192. The supporting jaw 193 is also centered similarly to the fixing jaw 194. The three sides protrude symmetrically by dividing the surface extending into the side at equal angles. That is, the inside of the fixing hole 192 corresponding to the fixing jaw 194 is opened, and the inside of the fixing hole 192 corresponding to the portion between the fixing jaw 194 extends toward the center side to fix the fixing jaw 194. To form. A locking surface 175 facing the first piston 160 is provided at the rear end of the second piston 170, and a fixing hole protrudes toward the first piston 160 at the center of the locking surface 175. A locking tube 176 and a locking protrusion 177 are provided to be inserted into the 192 to be supported on the support jaw 193. The catching tube 176 is a hollow tube protruding toward the first piston 160. The stem 180 of the first piston 160 when the first piston 160 and the second piston 170 are close to the inside thereof. The head portion 181 is provided to be inserted and the outer peripheral surface protruding toward the first piston 160 is spaced apart from the locking surface 175 by a predetermined interval and correspond to the fixing hole 192 to be inserted into the fixing hole 192. The locking projections 177 are provided in a shape that is provided, and each of the protrusions 177 protrudes symmetrically from each other by dividing portions protruded to the outer circumferential side such as the support jaw 193 and the fixing jaw 194 at equal angles. In between are formed spaced spaces provided symmetrically to each other. The locking protrusion 177 is inserted into the retainer 190 through the locking groove, and the surface facing the locking surface 175 spans the inner surface of the locking jaw by rotating the retainer 190. At the same time, the fixing jaw 194 is inserted between the locking surface 175 and the locking protrusion 177. For this purpose, the locking protrusion 177 formed to be spaced apart from the locking surface 175 has a width that is spaced apart from each other. One side is formed to become narrower. That is, the locking protrusion 177 is tapered toward the locking surface 175 side, and in the present invention, the thickness of the locking protrusion 194 is provided to become thick in the clockwise direction. The thickness is provided slightly larger than this so that the fixing jaw 194 can be inserted, and the thickness of the clockwise side tip is smaller than the thickness of the fixing jaw 194 so that the fixing jaw 194 can be fixed. This is squeezed and fixed.

The operation of the vehicle master cylinder of the present invention configured as described above is as follows. When the push rod 120 pushes the first piston 160 of the master cylinder 140 to generate pressure, the first sealing member 162 installed at the front side of the first piston 160 compresses the fluid and simultaneously cuts off the fluid. While passing through the hole 154, the oil is blocked from flowing into the first hydraulic chamber 151. At this time, as the refilling hole 155, the oil generated at the rear of the first piston 160 due to the forward movement of the first piston 160 while the oil at the rear side of the first piston 160 flows back to the oil tank 130. Will reduce the resistance. The oil is compressed in the first hydraulic chamber 151 by the forward movement of the first piston 160. As a result, the retainer 190 integrally formed with the second piston 170 is compressed while the first spring 161 is compressed. At this time, the operation pin of the center valve 174 installed in the second piston 170 is spaced apart from the stop pin 173 to block the oil supply to the second hydraulic chamber 152. Due to this operation, hydraulic pressure is generated in the first hydraulic chamber 151 and the second hydraulic chamber 152, and the wheels on the front wheel and the rear wheel side are connected to the first discharge pipe 153 and the second discharge pipe 156 connected thereto. Hydraulic pressure is supplied to a cylinder (not shown) to operate a brake (not shown). In addition, when the pressure is released after the brake (not shown), the push rod 120 is returned by the return spring 116, and the first piston 160 provided to be interlocked with the push rod 120 includes a push rod ( 120 and the first spring 161 return to the original state. At this time, since the first piston 160 and the second piston 170 are returned by the first spring 161, the first piston 160 and the second piston 170 can be quickly interlocked. Due to the return of the first piston 160, the head 181 of the stem 180 coupled to the front side of the first piston 160 pulls the retainer 190, and is formed integrally with the retainer 190. The two pistons 170 are moved to the rear to return to the original state.

That is, in the master cylinder 140 of the present invention, since the second piston 170 is interlocked by the return spring 116, a separate spring for returning the second piston 170 is deleted, thereby ensuring the durability of the spring. Since the second hydraulic chamber 152, which is a space required for the minimum compression of the space and the spring, can be reduced, the overall length of the master cylinder 140 can be reduced.

The present invention is designed to return the second piston by using the restoring force of the return spring to restore the push rod instead of using a separate spring installed on the second piston to restore the second piston. The length required for the working duration of the spring and the length to ensure the minimum length when compressed can be deleted, thereby reducing the total length of the master cylinder. As a result, it is possible to reduce material costs and processing time, and to facilitate the installation by reducing interference with peripheral components when installing the engine cylinder of the master cylinder.

Claims (2)

Booster provided with a return spring to return the push rod and the reciprocating motion, the cylinder body coupled to the booster and one side is opened so that one end of the push rod can be inserted, the cylinder body to be slid inside A first piston having an opening groove into which the push rod is inserted, is fixed to protrude toward a forward moving side of the first piston, and a stem provided with a head at the protruding end thereof, and the stem is inserted into and slides on one side thereof. And a retainer provided with a retainer hole so as to be pulled by the head during the backward movement of the first piston, and installed in close contact with the retainer so that the second piston can move forward by hydraulic pressure generated by the forward movement of the first piston. In a vehicle master cylinder equipped with a piston, A ring groove recessed in an circumferential direction on the inner surface of the opening groove so that the first piston can be returned by the return spring, and a fastening ring provided to expand and be inserted into the ring groove and inserted into the ring groove An insertion part provided as a spherical shape of an ellipse is provided at one side of the push rod so as to be fixed to the opening groove by the restoration of the fastening ring, and connects the push rod and the first piston. The fixing jaw and the plurality of fixing jaws symmetrically protruding from each other toward the center of the fixing hole and the fixing hole opened on the side facing the second piston of the retainer so as to be interlocked and returned due to the return of the first piston. And a retaining surface facing the retainer of the second piston so that the fixing jaw can be inserted between the plurality of engaging projections formed to correspond to the fixing holes and the engaging projections so as to span the inside of the retainer. Vehicle master cylinder, characterized in that the second piston is connected. The method of claim 1, The interval between the locking surface and the locking projection is narrowed so that the fixing jaw is inserted so that it can be compressed and fixed when the clockwise rotation is inserted.