KR20000016757U - Power steering device for vehicle - Google Patents

Abstract

The present invention relates to a vehicle power steering device, the purpose of which is to axially adhere to one side of the ball joint to compensate for the separation between the tie rod connecting ball and the ball joint when worn due to long-term use It is to provide a power steering apparatus for a vehicle having a spring that moves and compresses the inside thereof. The present invention is a cylinder provided to allow oil to flow into the inside, a rack bar extending to both sides of the outside of the cylinder, coupled to both ends of the rack bar, the diameter of the inlet portion formed to open to the outside is formed smaller than the inner ball is tapered The hollow ball seat is inserted into the housing, the ball housing and the one side is opened, the spherical contact portion is formed larger than the diameter of the open side of the ball sheet, the connection ball is inserted to rotate and bend in the interior of the contact portion Tie rod formed at one end, the contact portion of the tie rod and the ball seat is worn and the ball seat is moved to the inlet part on the inner side of the ball housing so as to compensate for the gap between the connecting ball and the ball. The elastic member is provided so that the close contact portion can be pressed toward the center side, and the steering force is accurately transmitted between the tie rod and the rack bar. Since it is possible to achieve this, the response of the front wheel to the driver's steering is improved, and noise due to the separation of the ball seat and the connection ball can be prevented, thereby improving reliability.

Description

Automotive Power Steering Device {POWER STEERING DEVICE FOR VEHICLE}

The present invention relates to a vehicle power steering device, and more particularly, a spring is provided on the other side of the wear part to compensate for the wear of the ball joint connecting the rack bar connected to the steering wheel side and the tie rod connected to the front wheel side. It relates to a vehicle power steering device provided.

In general, the vehicle is provided with a power steering device for steering the vehicle by hydraulic pressure generated by the driving of the engine for light and quick steering operation.

1 is a front sectional view showing a gearbox and a control valve of the conventional power steering device. As shown in the drawing, the gear box 30 is formed to be long to be connected to the front wheels of the vehicle, and a control valve 10 protruding upward and downward from the gear box 30 is provided at the middle side thereof. And between the control valve 10 and the gearbox 30 is installed a hydraulic pipe 20 through which the oil flows.

First, the control valve 10 is connected to a steering wheel provided in the driver's seat, and when the driver rotates the steering wheel, the oil flow path is adjusted accordingly, and the valve housing 11 is provided to form the exterior. . The valve port 12 is provided on the outside of the valve housing 11 to supply oil to the gearbox 30 so that one end of the hydraulic pipe 20 is coupled thereto. In addition, an inside of the valve housing 11 is provided with an input shaft 13 protruding upward and connected to a steering wheel.

Next, the gearbox 30 is a long cylinder, the outer appearance of the cylinder 40 is open on both sides. A rod-shaped rack bar 50 is installed inside the cylinder 40 so as to extend left and right through both ends of the cylinder 40. The both ends of the rack bar 50 is provided with a coupling hole 51 formed with a screw thread on the inner circumferential surface of the ball joint 70 to be installed later, the middle side of the rack bar (50) by dividing the internal space of the cylinder (40) A disk-shaped piston 52 which is slidably moved so that the rack bar 50 can be operated by the hydraulic pressure flowing therein is provided. In addition, the left and right sides of the piston 52 is provided with a cylinder port 41 protruding to the outer surface of the cylinder 40 so that oil flows into the cylinder 40, the piston 52 by the oil flowing through it ) And the rack bar 50 connected thereto is slidingly moved.

In addition, a rack bush 42 is provided between the outer circumferential surfaces of the rack bar 50 and the cylinder 40 to guide the movement of the rack bar 50 and prevent oil from leaking due to the movement of the rack bar 50. A pair of tie rods 60 are provided at both ends of the rack bar 50 positioned outside the rack bush 42. One end of the tie rod 60 is provided with a spherical connecting ball 61 to be connected to the rack bar 50 through the ball joint 70, the other end of the end rod 62 is screwed to the front wheel side of the vehicle It is prepared to be connected with.

Meanwhile, the ball joint 70 connecting the rack bar 50 and the tie rod 60 transmits the steering force generated by the driver to the front wheel and is provided to block external shock transmitted from the front wheel. A connecting shaft formed with a screw on the outer surface to be inserted into the ball housing 71 formed in one side is opened so that it can be connected to 60 and the coupling hole 51 of the rack bar 50 on the other side of the ball housing 71 72 is formed to protrude. In addition, a ball seat 73 is inserted into the ball joint 70 and fixed to the open side.

In addition, the ball seat 73 is provided with a hollow inside so that the connection ball 61 is coupled to support the rotation and refraction of the connection ball 61, one side of the opening is connected to the connection ball 61 is inserted The close contact portion 74 is provided to correspond to the shape of the connection ball 61 to be fixed. And the ball seat 73 is provided as a plastic injection molding so as to minimize the impact force transmitted from the front wheel side with the support of the connection ball 61 directly transmitted to the driver. The ball seat 73 is fixed to the ball seat 73 when it is inserted into the ball housing 71 and then presses the open side of the ball housing 71.

In the conventional vehicle power steering device configured as described above, when the driver rotates the steering wheel, the control valve 10 connected to the steering wheel supplies oil of the oil pump to the gearbox 30 side, and thus the gearbox 30. Piston 52 provided in the inside of is moved to one side with the rack bar (50). At this time, the ball joint 70 provided on both sides of the rack bar 50 is to transmit the operation of the rack bar 50 to the tie rod 60 and the end rod 62 to operate the front wheel. When the shock and vibration generated from the front wheel side are transmitted to the tie rod 60 while the vehicle is in operation, the ball joint 70 provided between the tie rod 60 and the rack bar 50 absorbs a part of the shock and vibration. Minimizing the transmission of vibration to the driver.

However, the conventional vehicle power steering apparatus configured as described above uses a high rigidity product for accurate transmission of steering force. The high rigidity ball seat wears down the inside of the ball seat closely contacted with the connection ball due to long-term use. It is deformed and spaced between the ball seat and the connecting ball. And due to the spacing generated between the ball seat and the connection ball, noise is generated when the rack bar and the tie rods interlock, and the operation of the rack bar is not correctly transmitted to the tie rods. As a result, the steering force of the driver may not be transmitted to the front wheels or delayed, thereby degrading steering of the vehicle.

The present invention is to solve such a problem, the purpose of the present invention is to adhere closely to one side of the ball joint to compensate for the separation between when the contact portion of the tie rod and the ball joint wears out due to long-term use It is to provide a power steering device for a vehicle having a spring for axially moving the part and pressing the inside thereof.

1 is a front sectional view showing a conventional power steering apparatus.

Figure 2 is an exploded perspective view showing a power steering apparatus according to the present invention.

3 is a cross-sectional view showing a state before coupling of the ball seat according to the present invention.

Figure 4 is a cross-sectional view showing a state after the coupling of the ball seat according to the present invention.

5 is a partially cutaway perspective view of the ball joint according to the present invention.

Explanation of symbols on the main parts of the drawings

130: gear box 150: rack bar 151: coupling hole

160: tie rod 161: connecting ball 170: ball joint

171: ball housing 172: insertion groove 173: inlet

174: connecting shaft 180: ball seat 181: close contact

190: elastic member

The present invention for achieving the above object, the cylinder is provided so that the oil can be introduced into the inside, the rack bar extending to both sides of the outer cylinder, the diameter of the inlet portion is coupled to both ends of the rack bar and formed to open outward than the inside Ball housing is formed small and tapered in the inner surface, the hollow ball seat is inserted into the inside of the ball housing, one side is opened, the spherical contact portion is formed larger than the diameter of one side opened in the ball sheet, the In the power steering device for a vehicle having a tie rod formed at one end of the connection ball is inserted so as to be rotated and refracted in the interior of the contact portion, the contact portion is worn to compensate for the separation between the connection ball and the On one side of the ball housing by moving the ball sheet to the inlet side by the inlet It characterized in that the elastic member is provided so as to be pressed toward the center portion in close contact group.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in detail.

Figure 2 is an exploded perspective view showing a power steering apparatus according to the present invention, Figure 3 is a cross-sectional view showing a state before coupling of the ball seat according to the present invention, Figure 4 is a cross-sectional view showing a state after the ball seat coupling according to the present invention to be. And Figure 5 is a partial cutaway perspective view of the ball joint according to the present invention. As shown in the drawing, the vehicle power steering apparatus of the present invention includes a gear box 130 that is provided to extend in the left and right direction, and a control valve 110 protruding upward and downward to cross the control box 110, and a control valve 110. It is provided with a hydraulic pipe 120 installed between the gear box 130.

First, the control valve 110 is provided with a valve housing 111 to form its appearance. The valve housing 111 is formed to be separated into the upper and lower, the lower side is formed integrally with the cylinder 140 of the gear box 130 to be rearranged, the upper side is provided to be coupled to the lower side, the outer gear box A valve port 112 having one end of the hydraulic pipe 120 coupled thereto is provided to supply oil to the 130. In addition, an inside of the valve housing 111 is provided with an input shaft 113 protruding upward and connected to a steering wheel, and a rotary valve for adjusting a flow path is provided in the not shown inside of the input shaft 113, such as a gear box 130. By regulating the oil supplied to the interior of the vehicle, power steering can be achieved. In addition, a pinion gear 114 is formed at the outer lower side of the input shaft 113 to achieve direct steering.

Next, the outer appearance of the gearbox 130 is a long cylindrical cylinder formed on both sides of the opening 140, the outside of the cylinder 140 is formed to protrude so as to communicate the inside and the outside of the cylinder 140 The cylinder port 141 is provided. The cylinder port 141 is connected to the control valve 110 through the hydraulic pipe (120).

In addition, a rod-shaped rack bar 150 is installed inside the cylinder 140. The rack bar 150 extends outward through the inside of the rack bush 142 sealing to both sides of the cylinder 140, the ball joint 170 to be installed in the rear end is inserted into the inner circumferential surface to be fixed A threaded coupling hole 151 is provided. And one side of the outer surface of the rack bar 150 is provided with a rack gear 152 to operate directly in accordance with the steering wheel operation of the driver. The rack gear 152 is provided to be engaged with the pinion gear 114 of the input shaft 113 in an throttled state so as to slide in the left and right directions. In addition, the inner side of the rack bar 150 bisects the inner space of the cylinder 140, the piston on the disk 153 to be moved to the left and right with the rack bar 150 by the hydraulic pressure flowing into the cylinder 140. ) Is provided. The piston 153 is installed between the cylinder port 141 and is slidably moved to the other side when oil is supplied through the cylinder port 141 on one side, thereby the inner space of the cylinder 140 on the other side of the piston 153 Oil is to be moved to the control valve 110 side through the cylinder port 141 of the other side.

In addition, a pair of tie rods 160 are provided at both ends of the rack bar 150. One end of the tie rod 160 is provided with a spherical connecting ball 161 to be connected to the rack bar 150 through the ball joint 170, the other end of the tie rod 160 is screwed to the front wheel side of the vehicle It is prepared to be connected with. The end rod 162 is installed in a straight line on the same line as the rack bar 150, tie rod 160, the outer end is projected upward to the knuckle arm (not shown) of the front wheel side is coupled. As a result, the tie rod 160, the end rod 162, and the front wheel are operated in accordance with the operation of the rack bar 150 to generate steering force.

Meanwhile, a ball joint 170 is provided between the rack bar 150 and the tie rod 160. The ball joint 170 is provided to transmit steering force generated by the driver to the front wheel and to block external shock transmitted from the front wheel, and an insertion groove having one side open to be connected to the tie rod 160. A ball housing 171 having a 172 formed therein and a connecting shaft 174 having a screw formed on an outer surface thereof are protruded to be inserted into the coupling hole 151 of the rack bar 150 at the other side of the ball housing 171.

In addition, the ball seat 180 is provided in the ball joint 170, the connection ball 161 is inserted and fixed. The ball seat 180 is a characteristic component of the present invention, it is provided as a plastic injection molding to minimize the impact force transmitted from the front wheel side with the support of the connection ball 161 is directly transmitted to the driver, this More detailed description is as follows.

First, the ball seat 180 is provided with an outer surface of a cylindrical shape so that it can be fitted into the insertion groove 172 inside the ball housing 171. In addition, the ball seat 180 is inserted into the ball housing 171 to firmly couple the ball seat 180, and then the open inlet 173 of the insertion groove 172 is pressed from the outside. As a result, the inlet 173 is formed to have a smaller diameter than the inner diameter due to external pressure, and the inner surface of the insertion groove 172 is tapered. As a result, the open end of the insertion groove 172 is deformed toward the center side to prevent the external departure of the ball seat 180. On the contrary, a separation distance G is generated between the inner surface formed inside the insertion groove 172 and the outer circumferential surface of the ball seat 180 facing the insertion groove 172.

Next, the inside of the ball seat 180 is provided to be opened to one side in the axial direction, the contact portion 181 inside the open side of the ball housing 171 so that the connection ball 161 of the tie rod 160 can be inserted. ) Is provided. The close contact portion 181 has a spherical shape corresponding to the connection ball 161 so that the connection ball 161 can be rotated and refracted, the opening side is the connection ball 161 of the tie rod 160 is inserted It is provided with a diameter smaller than the maximum diameter of the connection ball 161 to be fixed, the connection ball 161 is forcibly inserted.

In addition, an elastic member 190 is installed between the closed inner side of the insertion groove 172 and the ball seat 180 to axially support the ball seat 180 toward the inlet 173. The elastic member 190 is provided in a circular shape, the cross section is a leaf spring is provided in a waveform. In addition, the elastic member 190 is compressed as much as possible, and the diameter when the outer circumferential side is extended is formed to be smaller than the inner diameter of the insertion groove 172 to prevent it from being fixed inside the insertion groove 172. That is, the outer circumferential surface of the elastic member 190 is in close contact with the inner surface of the insertion groove 172 and is not able to exert an elastic force to support the ball seat 180 toward the inlet portion 173 side of the ball housing 171. The maximum diameter is to be formed smaller than the diameter of the insertion groove 172 to prevent the missing. In addition, since the cross-section is provided in a waveform having a small deformation amount during compression and restoration, the internal space of the ball housing 171 is occupied less.

The elastic member 190 is previously inserted into the ball seat 180 before inserting the ball seat 180 into the insertion groove 172 inside the ball housing 171. Since the ball seat 180 is axially pressed into the insertion groove 172 after the insertion and installation of the elastic member 190, the elastic member 190 is in a compressed state so that the insertion groove 172 is expandable. ) And the ball seat 180 is located, because the cross-section is expanded, the space occupied between the insertion groove 172 and the ball seat 180 is very small. In addition, the inlet portion 173 of the ball housing 171 into which the elastic member 190 and the ball seat 180 are inserted therein is pressed from the outside so that the elastic member 190 and the ball seat 180 are disposed in the ball housing ( It is prevented to be separated to the outside of the insertion portion of the 171. Thus, the ball seat 180 is elastically supported by the elastic member 190 toward the inlet 173, the contact portion 181 of the ball seat 180 is tapered inlet 173 is a narrow side As the ball seat 180 is moved to the side, the ball sheet 180 is pressed to the center side, and is more tightly connected to the connection ball 161.

Operation of the vehicle power steering apparatus of the present invention configured as described above is as follows. As the driver manipulates the steering wheel provided in the driver's seat, the pinion gear 114 is rotated, and the pinion gear 114 and the meshed rack gear 152 move in one direction. As a result, oil is supplied to the cylinder 140 so that the rack bar 150 can move in the direction in which the steering wheel rotates, so that the piston 153 is slid by hydraulic pressure so that the driver can easily turn the steering wheel. At this time, since the ball joint 170 of the present invention has a connection ball 161 and the close contact portion 181 is provided in a spherical shape, the ball joint 170 can be deformed in the direction of rotation and deflection, and the material of the ball seat 180 is made of plastic. Absorbs shock and vibration transmitted to the driver through the tie rod 160 to minimize the shock and vibration transmitted to the driver. In addition, the elastic member 190 elastically supports the ball sheet 180 toward the inlet portion 173, which is a narrow side of the tapered shape, and thus the close contact portion 181 of the ball sheet 180 is connected to the inlet portion 173. By pressing to the center side is more tightly contact with the connection ball 161. In addition, when the ball joint 170 is used for a long time, the connecting ball 161 made of metal wears the contact portion 181 of the ball seat 180 made of plastic material, and the elastic member 190 is spaced apart therebetween. By pushing the ball seat 180 toward the inlet 173, the close contact 181 is pressed toward the center to compensate for the separation caused by wear.

As described in detail above, the power steering apparatus according to the present invention, as described in detail above, the power steering apparatus according to the present invention, to provide an elastic member to compensate for the separation generated between the ball seat and the connection ball. As a result, the ball seat and the connection ball are firmly coupled, which enables accurate steering force transmission between the tie rod and the rack bar. As a result, the response of the front wheels to the driver's steering is improved, and noise due to the separation of the ball seat and the connection ball can be prevented, thereby improving the reliability of the power steering apparatus.

Claims (2)

A cylinder provided to allow oil to flow into the inside, a rack bar extending to both sides of the outside of the cylinder, and a diameter of the inlet portion which is coupled to both ends of the rack bar and formed to open outward is smaller than the inside so that the inner surface is tapered. A hollow ball sheet inserted into the ball housing and having one side opened, a spherical contact portion formed larger than a diameter of one side opened in the ball sheet, and inserted to rotate and refract inside the contact portion; In the vehicle power steering apparatus having a tie rod formed at one end thereof, The contact part is worn to the inner side of the ball housing to compensate for the separation between the connection ball and wear the ball to the inlet portion side so that the contact portion can be pressed to the center side by the inlet portion Vehicle power steering apparatus characterized in that the elastic member is provided. The method of claim 1, The elastic member is a vehicle power steering apparatus, characterized in that it is installed in a compressed state inside the ball housing so as to move the ball seat axially toward the inlet side as a leaf spring formed to be curved in a wave shape.