CN102815334B - Travel unloading mechanism of recirculating ball-type power steering gear of automobile - Google Patents

Abstract

The invention belongs to the technology of power steering gears of automobiles, relates to improvement of a recirculating ball-type power steering gear, and discloses a travel unloading mechanism of a recirculating ball-type power steering gear of an automobile. The travel unloading mechanism comprises a steering gear lower shell (1), a steering nut (2) and a combined sealing component (3), and the combined sealing component (3) is positioned in a sealing groove on a cylindrical surface of the right end of the steering nut (2). The travel unloading mechanism is characterized in that a left steel ball hole (15) of a left unloading hole (10) and a screw ring (13) are arranged at an outer port of the left unloading hole (10), a steel ball (12) is arranged in an unthreaded hole of the left steel ball hole (15), and a conical surface (14) is arranged on an inner port of a center hole of the screw ring (13); and a right steel ball hole (17) of a right unloading hole (8) is arranged on an outer port of the right unloading hole (8), another steel ball (12) is disposed in the right steel ball hole (17), and a conical surface (18) is arranged on an outer port of the right unloading hole (8). By the aid of the travel unloading mechanism, the problem of boosting failure of a travel unloading structure of a recirculating ball-type power steering gear of an automobile under specific conditions can be avoided, and reliability is improved.

Description

Recirculating ball type automobile power steering gear stroke unloading mechanism

technical field

The invention belongs to the technology of the automobile power steering gear and relates to the improvement of the circulating ball type automobile power steering gear.

Background technique

Chinese invention patent application "Stroke Unloading Structure of Recirculating Ball Automotive Power Steering Gear" (Application No.: 201110117749.0) discloses a stroke unloading structure of recirculating ball automotive power steering gear, which simplifies the original stroke unloading mechanism The structure facilitates the processing and reduces the cost. Its disadvantages are: there is a problem of power failure in certain situations, for example, when the car wheel is stuck in the unloaded position or sunken into a pit and it is difficult to turn, because the left chamber and the right chamber have been connected, when the steering wheel is rotated in the opposite direction, the steering wheel The internal pressure of the device cannot be established, and no power assistance can be generated. Only manual torque can be used to make the wheels return to normal, which makes it very laborious to rotate the steering wheel in the opposite direction.

Contents of the invention

The object of the present invention is to propose a stroke unloading structure of a recirculating ball type automobile power steering gear that can avoid power failure.

The technical solution of the present invention is: a recirculating ball type automobile power steering gear stroke unloading mechanism, including a steering gear lower housing 1, a steering nut 2 and a combined sealing assembly 3 located in the sealing groove on the right-hand cylindrical surface of the steering nut 2. The lower part of the left end of the nut 2 has a rack that meshes with the gear sector on the rocker shaft 11. The right end of the steering nut 2 is inserted into the cylindrical right cavity 4 of the lower housing 1 and maintains a clearance fit. The combined sealing assembly 3 seals the right end of the steering nut 2. The gap between the cylindrical surface and the inner wall of the right chamber 4 is sealed, and the inner chamber of the lower housing on the left and lower sides of the steering nut 2 constitutes the left chamber 5, and the right chamber 4 and the left chamber 5 respectively pass through the oil circuit inside the lower housing 1 and the rotary valve mechanism The corresponding ports are connected, and the upper half of the cylindrical surface of the steering nut 2 is attached to the upper inner wall of the inner cavity of the lower housing 1; there is an arc groove 6 extending along the circumferential direction on the upper inner wall of the inner cavity of the lower housing 1. The width of the arc groove 6 along the axial direction of the steering nut 2 is L, and the distance between the vertical middle plane of the arc groove 6 along the width direction and the vertical middle plane of the rocker shaft 11 is D; at the right end of the steering nut 2 There is a blind hole 7 perpendicular to the right end face on the upper part of the surface, a left unloading hole 10 and a right unloading hole 8 are arranged on the upper part of the steering nut 2 cylindrical surface, the inner port of the left unloading hole 10 is connected with the left end of the blind hole 7 Connected, the inner port of the right unloading hole 8 communicates with the right part of the blind hole 7; on the cylindrical surface of the steering nut 2, there is an annular groove 9 between the left unloading hole 10 and the right unloading hole 8; its characteristics in:

(1) At the outer port of the left unloading hole 10, there is a left steel ball hole 15 whose diameter is larger than that of the left unloading hole 10. The outer port of the left steel ball hole 15 is located on the cylindrical surface of the steering nut 2. The left steel ball hole 15 It forms a stepped hole with the left unloading hole 10. There is an internal thread 16 at the part of the left steel ball hole 15 near the outer port, and a spiral ring 13 is screwed into the internal thread 16. In the light hole part of the left steel ball hole 15 There is a steel ball 12, the diameter of the steel ball 12 is larger than the diameter of the left unloading hole 10 and the central hole of the spiral ring 13, from the inner end surface of the spiral ring 13 to the step end surface between the left unloading hole 10 and the left steel ball hole 15 The distance is greater than the diameter of the steel ball 12, the inner port of the central hole of the spiral ring 13 has a conical surface 14, and at least one of the step end faces between the left unloading hole 10 and the left steel ball hole 15 communicates with the left unloading hole 10 The discharge groove; the distance from the left steel ball hole 15 to the left edge of the annular groove 9 is less than the width L of the arc groove 6 on the steering nut 2. When the steering nut 2 is at the right unloading position, the arc groove 6 will be the The ball hole 15 communicates with the annular groove 9, so that the left chamber 5 communicates with the right chamber 4 through the annular groove 9, the arc groove 6, the left steel ball hole 15, the left unloading hole 10, the discharge groove and the blind hole 7;

(2) At the outer port of the right unloading hole 8, there is a right steel ball hole 17 whose diameter is larger than that of the right unloading hole 8. The outer port of the right steel ball hole 17 is located on the cylindrical surface of the steering nut 2. The right steel ball hole 17 Form a step hole with the right unloading hole 8, and there is a steel ball 12 in the right steel ball hole 17, the diameter of the steel ball 12 is greater than the aperture of the right unloading hole 8, and the depth of the right steel ball hole 17 is greater than that of the steel ball 12 diameter, the outer port of the right unloading hole 8 has a conical surface 18, the distance from the right steel ball hole 17 to the right edge of the annular groove 9 is equal to the distance from the left steel ball hole 15 to the left edge of the annular groove 9, when the steering nut 2 When it is in the left unloading position, the arc groove 6 connects the right steel ball hole 17 with the annular groove 9, so that the right cavity 4 passes through the blind hole 7, the right unloading hole 8, the right steel ball hole 17, and the arc groove 6 And the annular groove 9 communicates with the left cavity 5 .

The invention has the advantages of being able to avoid the problem of failure of power assistance in the stroke unloading structure of the recirculating ball type automobile power steering gear under specific circumstances, and improve the reliability.

Description of drawings

Fig. 1 is a structural schematic diagram of the present invention.

Fig. 2 is an enlarged view of part A in the present invention.

Detailed ways

The present invention will be described in further detail below. Referring to Figures 1 and 2, the recirculating ball type automotive power steering gear stroke unloading mechanism includes the steering gear lower housing 1, the steering nut 2 and the combined sealing assembly 3 located in the sealing groove on the right cylindrical surface of the steering nut 2. 2 The lower part of the left end has a toothed rack that meshes with the gear sector on the rocker shaft 11. The right end of the steering nut 2 is inserted into the cylindrical right cavity 4 of the lower housing 1 and maintains a clearance fit. The combined sealing assembly 3 seals the right end of the steering nut 2 The gap between the surface and the inner wall of the right chamber 4 is sealed, and the inner chamber of the lower housing on the left and lower sides of the steering nut 2 constitutes the left chamber 5, and the right chamber 4 and the left chamber 5 respectively correspond to the rotary valve mechanism through the oil circuit inside the lower housing 1. The upper part of the cylindrical surface of the steering nut 2 is attached to the upper inner wall of the inner cavity of the lower housing 1; there is an arc groove 6 extending in the circumferential direction on the upper inner wall of the inner cavity of the lower housing 1. The width of the slot 6 along the axial direction of the steering nut 2 is L, and the distance between the vertical mid-section of the arc groove 6 along the width direction and the vertical mid-section of the rocker shaft 11 is D; There is a blind hole 7 perpendicular to the right end surface in the upper part of the steering nut 2, a left unloading hole 10 and a right unloading hole 8 are arranged on the upper part of the steering nut 2 cylindrical surface, and the inner port of the left unloading hole 10 communicates with the left end of the blind hole 7 , the inner port of the right unloading hole 8 communicates with the right part of the blind hole 7; on the cylindrical surface of the steering nut 2, there is an annular groove 9 between the left unloading hole 10 and the right unloading hole 8; it is characterized in that :

(1) At the outer port of the left unloading hole 10, there is a left steel ball hole 15 whose diameter is larger than that of the left unloading hole 10. The outer port of the left steel ball hole 15 is located on the cylindrical surface of the steering nut 2. The left steel ball hole 15 It forms a stepped hole with the left unloading hole 10. There is an internal thread 16 at the part of the left steel ball hole 15 near the outer port, and a spiral ring 13 is screwed into the internal thread 16. In the light hole part of the left steel ball hole 15 There is a steel ball 12, the diameter of the steel ball 12 is larger than the diameter of the left unloading hole 10 and the central hole of the spiral ring 13, from the inner end surface of the spiral ring 13 to the step end surface between the left unloading hole 10 and the left steel ball hole 15 The distance is greater than the diameter of the steel ball 12, the inner port of the central hole of the spiral ring 13 has a conical surface 14, and at least one of the step end faces between the left unloading hole 10 and the left steel ball hole 15 communicates with the left unloading hole 10 The discharge groove; the distance from the left steel ball hole 15 to the left edge of the annular groove 9 is less than the width L of the arc groove 6 on the steering nut 2. When the steering nut 2 is at the right unloading position, the arc groove 6 will be the The ball hole 15 communicates with the annular groove 9, so that the left chamber 5 communicates with the right chamber 4 through the annular groove 9, the arc groove 6, the left steel ball hole 15, the left unloading hole 10, the discharge groove and the blind hole 7;

(2) At the outer port of the right unloading hole 8, there is a right steel ball hole 17 whose diameter is larger than that of the right unloading hole 8. The outer port of the right steel ball hole 17 is located on the cylindrical surface of the steering nut 2. The right steel ball hole 17 Form a step hole with the right unloading hole 8, and there is a steel ball 12 in the right steel ball hole 17, the diameter of the steel ball 12 is greater than the aperture of the right unloading hole 8, and the depth of the right steel ball hole 17 is greater than that of the steel ball 12 diameter, the outer port of the right unloading hole 8 has a conical surface 18, the distance from the right steel ball hole 17 to the right edge of the annular groove 9 is equal to the distance from the left steel ball hole 15 to the left edge of the annular groove 9, when the steering nut 2 When it is in the left unloading position, the arc groove 6 connects the right steel ball hole 17 with the annular groove 9, so that the right cavity 4 passes through the blind hole 7, the right unloading hole 8, the right steel ball hole 17, and the arc groove 6 And the annular groove 9 communicates with the left cavity 5 .

The working principle of the present invention is: when the wheel is stuck in the left unloading position or sinks into a pit, and the steering wheel rotates in the opposite direction, the left chamber 5 and the right chamber 4 high-pressure oil switch, the left chamber 5 enters the high-pressure oil, and the right steel The steel ball 12 in the ball hole 17 and the conical surface 18 form a conical surface seal, so that the left chamber 5 and the right chamber 4 are not connected, and the left chamber forms a high-pressure oil chamber to generate power, reduce the manual torque of the steering wheel, and facilitate the wheel to return to alignment;

When the wheel is stuck at the right unloading position or sinks into a pit, and when the steering wheel rotates in the opposite direction, the high-pressure oil in the left chamber 5 and the right chamber 4 is switched, and the right chamber 4 enters the high-pressure oil, and the steel ball 12 in the left steel ball hole 15 The conical surface 14 impacted by the oil to the inner port of the spiral ring 13 forms a conical surface seal, so that the left chamber 5 and the right chamber 4 are not connected, and the right chamber forms a high-pressure oil chamber to generate power, reduce the manual torque of the steering wheel, and facilitate the wheel to return .

Claims (1)

1. automobile circulating ball type power steering gears stroke unloading mechanism, comprise deflector lower house (1), steering nut (2) and be positioned at the combination sealing assembly (3) of seal groove on steering nut (2) the right-hand member face of cylinder, have in steering nut (2) left end bottom and fan with the tooth on rocker shaft (11) tooth bar engaged, keep free-running fit in the cylindrical right chamber (4) that the right-hand member of steering nut (2) inserts lower house (1), combination sealing assembly (3) is by the clearance seal between steering nut (2) the right-hand member face of cylinder and right chamber (4) inwall, steering nut (2) left side and following lower housing cavity form left chamber (5), right chamber (4) is communicated with respectively by the port that the oil circuit that lower house (1) is inner is corresponding to rotary valve mechanism with left chamber (5), the first half face of cylinder of steering nut (2) and the upper inside wall of lower house (1) inner chamber are fitted, an arc groove along the circumferential direction stretched (6) is had in the upper inside wall of lower house (1) inner chamber, this arc groove (6) is L along the width that steering nut (2) is axial, and the distance between the vertical split of this arc groove (6) broad ways and the vertical split of rocker shaft (11) is D, a blind hole perpendicular to right side (7) is had on the top of the right side of steering nut (2), a left unloading hole (10) and right unloading hole (8) is had on the top on steering nut (2) face of cylinder, the inner port of left unloading hole (10) is communicated with the left end of blind hole (7), and the inner port of right unloading hole (8) is communicated with the right part of blind hole (7), an annular groove (9) is had on the face of cylinder of steering nut (2), between left unloading hole (10) and right unloading hole (8), it is characterized in that:

(1) diameter is had to be greater than the left steel ball hole (15) of left unloading hole (10) in the external port of left unloading hole (10), the external port of left steel ball hole (15) is positioned on the face of cylinder of steering nut (2), left steel ball hole (15) and left unloading hole (10) form a stepped hole, at left steel ball hole (15) near the part of external port with negative thread (16), a volution (13) is had to be screwed in negative thread (16), a steel ball (12) is had in the unthreaded hole part of left steel ball hole (15), the diameter of steel ball (12) is greater than the aperture of left unloading hole (10) and volution (13) centre hole, distance from volution (13) inner end surface to the step end face left unloading hole (10) and left steel ball hole (15) is greater than the diameter of steel ball (12), the inner port of volution (13) centre hole is with circular conical surface (14), step end face between left unloading hole (10) with left steel ball hole (15) there is the dredging flow groove that at least one is communicated with left unloading hole (10), left steel ball hole (15) is less than to the distance of annular groove (9) left hand edge the width L that steering nut (2) goes up arc groove (6), when steering nut (2) is positioned at right unloaded position, left steel ball hole (15) is communicated with annular groove (9) by arc groove (6), and left chamber (5) is communicated with right chamber (4) with blind hole (7) by annular groove (9), arc groove (6), left steel ball hole (15), left unloading hole (10), dredging flow groove,

(2) diameter is had to be greater than the right steel ball hole (17) of right unloading hole (8) in the external port of right unloading hole (8), the external port of right steel ball hole (17) is positioned on the face of cylinder of steering nut (2), right steel ball hole (17) and right unloading hole (8) form a stepped hole, a steel ball (12) is had in right steel ball hole (17), the diameter of steel ball (12) is greater than the aperture of right unloading hole (8), the degree of depth of right steel ball hole (17) is greater than the diameter of steel ball (12), the external port of right unloading hole (8) is with circular conical surface (18), right steel ball hole (17) is equal to the distance of annular groove (9) left hand edge with left steel ball hole (15) to the distance of annular groove (9) right hand edge, when steering nut (2) is positioned at left unloaded position, right steel ball hole (17) is communicated with annular groove (9) by arc groove (6), make right chamber (4) by blind hole (7), right unloading hole (8), right steel ball hole (17), arc groove (6) is communicated with left chamber (5) with annular groove (9).