Pressing mechanism for stepless automatic compensation of gap between gear and rack on steering engine

Abstract

The utility model relates to the technical field of steering systems, in particular to a pressing mechanism for stepless automatic compensation of a gap between a gear and a rack on a steering engine. A pressing mechanism for stepless automatic compensation of a gear rack gap on a steering engine is characterized in that the top of a pressing block is connected with one end of a main shaft, the other end of the main shaft is connected with an adjusting nut, and a fixing pin penetrates through the adjusting nut and the main shaft from top to bottom to be connected with the pressing block; a main shaft nut sleeves the outer side of one end of the main shaft; a small compression spring sleeves the outer side of the upper part of the main shaft nut; the top of the main shaft is sleeved with a plane needle bearing and a gasket. A large compression spring is embedded in the bottom of the adjusting nut; the bottom of the pressing block is connected with a pressing block gasket. Compared with the prior art, gear and rack gaps increased due to abrasion of components in the using process of the steering machine can be automatically compensated through a mechanical structure, compensation is stepless, namely, the abrasion compensation amount enables the pressing block gaps to be kept in the initial design state all the time, and noise is prevented from being generated.

Description

Technical Field

[0001] The utility model relates to the technical field of steering systems, in particular to a clamping mechanism for steplessly and automatically compensating for gear rack clearance on a steering machine. Background Art

[0002] The traditional clamping mechanism is composed of an adjusting nut, a compression spring, a pressure block, a pressure block lining, a sealing ring, etc. In order to ensure that the rack moving force meets the requirements during the rack movement, a certain amount of clearance is made between the pressure block and the adjusting nut during the steering gear assembly. When the gear and rack are driven, the axial force provided by the compression spring and the sealing ring can ensure that the gear and rack do not produce any impact noise in this clearance state. However, when the gear and rack are worn during the use of the steering gear, or the rack and pressure block lining are worn, or the adjusting nut is loosened, the clearance between the pressure block assembly and the adjusting nut increases, which further increases the clearance between the gear and rack. The traditional clamping mechanism cannot automatically compensate for the wear, thus causing noise. Utility Model Content

[0003] The utility model overcomes the deficiencies of the prior art and provides a clamping mechanism for steplessly and automatically compensating for the clearance between gears and racks on a steering machine. The mechanical structure can automatically compensate for the clearance between gears and racks that increases due to wear of components during use of the steering machine, and the compensation is stepless, that is, the compensation is made in proportion to the wear, so that the clearance between the pressing blocks is always maintained at the originally designed state, thereby preventing noise from being generated.

[0004] In order to achieve the above-mentioned purpose, a clamping mechanism for steplessly and automatically compensating the clearance between gear racks on a steering gear is designed, comprising an adjusting nut, a clamping block, and a clamping block gasket, and characterized in that: the top of the clamping block is connected to one end of the main shaft, the other end of the main shaft is connected to the adjusting nut, and the fixing pin passes through the adjusting nut, the main shaft and the clamping block from top to bottom respectively; a main shaft nut is sleeved on the outer side of one end of the main shaft, and a small compression spring is sleeved on the upper outer side of the main shaft nut; a plane needle roller bearing and a gasket are sleeved on the top of the main shaft; a large compression spring is embedded in the bottom of the adjusting nut; and the bottom of the clamping block is connected to the clamping block gasket.

[0005] The body of the pressing block is a cylindrical structure, a pressing block annular groove is arranged on the top of the pressing block, and the bottom of the pressing block is an arc structure; a plurality of sealing ring grooves are arranged on the outer edge of the pressing block body, and sealing rings are embedded in the sealing ring grooves.

[0006] A fixing pin installation groove connected with the fixing pin is arranged at the bottom center of the annular groove of the pressing block at the top of the pressing block, and pressing block positioning holes connected with the spindle nut are arranged on both sides of the fixing pin installation groove.

[0007] The spindle nut is a stepped cylindrical structure, and an inner spiral trapezoidal tooth connected to the spindle is provided at the center of the upper cylinder of the spindle nut, and a spindle nut positioning protrusion connected to the pressure block positioning hole of the pressure block is provided at the bottom of the spindle nut.

[0008] The spindle is a bolt structure, a spindle center hole connected to a fixing pin is arranged at the center of the spindle, a spindle positioning protrusion is arranged at the top of the spindle, and an external spiral trapezoidal tooth connected to a spindle nut is arranged at the bottom of the spindle.

[0009] The pressing block gasket is an arc-shaped sheet structure, the top of the pressing block gasket is connected to the bottom of the pressing block, and the bottom of the pressing block gasket abuts against the rack.

[0010] The gasket is located above the plane needle roller bearing, and the gasket and the plane needle roller bearing are sleeved on the main shaft positioning protrusion of the main shaft.

[0011] The bottom of the adjusting nut is located above the pressing block, and a gap is provided between the bottom plane of the adjusting nut and the top plane of the pressing block.

[0012] Compared with the prior art, the utility model provides a clamping mechanism for steplessly and automatically compensating the clearance between gears and racks on a steering machine. The mechanical structure can automatically compensate the clearance between gears and racks that increases due to wear of components during the use of the steering machine, and the compensation is stepless, that is, the compensation is made in proportion to the wear, so that the clearance between the pressing blocks is always maintained at the originally designed state, thereby preventing noise from being generated. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the structure of the utility model.

[0014] Figure 2 It is a cross-sectional view of the structure of the utility model.

[0015] Figure 3 for Figure 2 A partial enlarged view of .

[0016] Figure 4 This is a schematic diagram of the structure of the medium pressure block of the utility model.

[0017] Figure 5 It is a schematic diagram of the structure of the spindle nut in the utility model.

[0018] Figure 6 It is a schematic diagram of the main shaft structure in the utility model.

[0019] Figure 7 It is a schematic diagram of the structure of the plane needle roller bearing in the utility model.

[0020] Figure 8 Schematic diagram of the main shaft force analysis model.

[0021] Fig. 9 The utility model is installed on the steering machine schematic diagram. DETAILED DESCRIPTION

[0022] The utility model is further described below with reference to the accompanying drawings.

[0023] like Figures 1 to 7 As shown, the top of the pressure block 10 is connected to one end of the main shaft 7, and the other end of the main shaft 7 is connected to the adjusting nut 4. The fixing pin 1 passes through the adjusting nut 4, the main shaft 7 and the pressure block 10 from top to bottom respectively; a main shaft nut 8 is sleeved on the outer side of one end of the main shaft 7, and a small compression spring 3 is sleeved on the upper outer side of the main shaft nut 8; a plane needle bearing 6 and a gasket 5 are sleeved on the top of the main shaft 7; a large compression spring 2 is embedded at the bottom of the adjusting nut 4; the bottom of the pressure block 10 is connected to the pressure block gasket 11.

[0024] The body of the pressing block 10 is a cylindrical structure, a pressing block annular groove 10-1 is provided at the top of the pressing block 10, and the bottom of the pressing block 10 is an arc structure; a plurality of sealing ring grooves 10-2 are provided at the outer edge of the pressing block 10 body, and a sealing ring 9 is embedded in the sealing ring groove 10-2.

[0025] A fixing pin installation groove 10-3 connected to the fixing pin 1 is provided at the bottom center of the pressing block annular groove 10-1 at the top of the pressing block 10, and pressing block positioning holes 10-4 connected to the spindle nut 8 are provided on both sides of the fixing pin installation groove 10-3.

[0026] The spindle nut 8 is a stepped cylindrical structure. An inner spiral trapezoidal tooth 8-1 connected to the spindle 7 is provided at the center of the upper cylinder of the spindle nut 8. A spindle nut positioning protrusion 8-2 connected to the pressure block positioning hole 10-4 of the pressure block 10 is provided at the bottom of the spindle nut 8.

[0027] The main shaft 7 is a bolt structure, with a main shaft center hole 7-1 connected to the fixing pin 1 at the center of the main shaft 7, a main shaft positioning protrusion 7-2 at the top of the main shaft 7, and an external spiral trapezoidal tooth 7-3 connected to the main shaft nut 8 at the bottom of the main shaft 7.

[0028] The pressing block gasket 11 is an arc-shaped sheet structure, the top of the pressing block gasket 11 is connected to the bottom of the pressing block 10, and the bottom of the pressing block gasket 11 abuts against the rack.

[0029] The gasket 5 is located above the plane needle roller bearing 6 , and the gasket 5 and the plane needle roller bearing 6 are sleeved on the main shaft positioning protrusion 7 - 2 of the main shaft 7 .

[0030] The bottom of the adjusting nut 4 is located above the pressing block 10 , and a gap is provided between the bottom plane of the adjusting nut 4 and the top plane of the pressing block 10 .

[0031] like Figure 1 , Figure 2 As shown, the sealing ring 9 is placed in the sealing ring groove 10-2 of the pressure block 10, the spindle nut 8 is placed on the pressure block 10, and is connected through the spindle nut positioning protrusion 8-2 of the spindle nut 8 and the pressure block positioning hole 10-4 of the pressure block 10, the spindle 7 is on the spindle nut 8, and the spiral trapezoidal teeth cooperate with each other, the small compression spring 3 is between the spindle 7 and the spindle nut 8, and the spindle 7, the spindle nut 8 and the pressure block 10 are connected together through the fixing pin 1, the plane needle bearing 6 cooperates with the spindle positioning protrusion 7-2 of the spindle 7, the gasket 5 is placed on the plane needle bearing 6, the gasket 5 is in contact with the adjusting nut 4, the large compression spring 2 is placed in the annular groove of the adjusting nut 4, and between the pressure block annular groove 10-1 of the pressure block 10, and the adjusting nut 4 is threaded.

[0032] like Fig. 9 As shown, the structure of the utility model is installed on the steering gear housing. Figures 1 to 7 As shown, the rack 12 is meshed with the gear 13 and then pressed by the clamping mechanism of the utility model; the sealing ring 9 is placed in the sealing ring groove 10-2 of 10 and has an interference fit with the steering gear housing; the pressing block lining 11 below the pressing block 10 cooperates with the rack 12; the spindle nut 8 is placed on the pressing block 10, and the rotational movement of the spindle nut 8 is limited by the spindle nut positioning protrusion 8-2 of the spindle nut 8 and the pressing block positioning hole 10-4 of the pressing block 10; the spindle 7 is on the spindle nut 8, and the inner spiral trapezoidal teeth 8-1 of the spindle nut 8 and the outer spiral trapezoidal teeth 7-3 of the spindle 7 cooperate, and the fixing pin 1 passes through the spindle center hole 7-1 on the spindle 7 and the pressing block 10 The fixing pin mounting groove 10-3 on it is assembled; the small compression spring 3 is between the main shaft 7 and the main shaft nut 8, and is used to compensate for the increased gap between the pressure block 10 and the adjusting nut 4; the plane needle bearing 6 and the main shaft positioning protrusion 7-2 of the main shaft 7 are matched, and the gasket 5 is placed on the plane needle bearing 6, and the gasket 5 is in contact with the bottom plane of the adjusting nut 4. The large compression spring 2 is placed between the annular groove of the adjusting nut 4 and the pressure block annular groove 10-1 of the pressure block 10. The adjusting nut 4 is matched with the steering gear housing through threads. After the adjusting nut 4 is assembled, the lower plane at the bottom of the adjusting nut 4 and the upper plane at the top of the pressure block 10 have a gap between the adjusting nut 4 and the pressure block 10.

[0033] The principle of the utility model is as follows: the clamping mechanism of the utility model is installed on the steering gear housing. The gear 13 and the rack 12 are meshed with teeth to convert the rotational motion of the gear 13 into the axial linear motion of the rack 12; the clamping mechanism provides the back clamping force of the rack 12 for the meshing of the rack 12 and the gear 13. After the adjustment nut 4 is assembled, there is a gap between the lower plane of the bottom of the adjustment nut 4 and the upper plane of the top of the pressure block 10. The sealing ring 9 is placed in the sealing ring groove 10-2 of the pressure block 10, and has an interference fit with the steering gear housing, which plays a role in sealing and providing damping for the pressure block; the pressure block lining 11 under the pressure block 10 cooperates with the rack 12; the small compression spring 3 is in a compressed state between the main shaft 7 and the main shaft nut 8, and in the compressed state, the inner spiral trapezoidal teeth 8-1 of the main shaft nut 8 and the outer spiral trapezoidal teeth 7-3 of the main shaft 7 cooperate, and the outer spiral trapezoidal teeth 7-3 of the main shaft 7 are pressed and fitted with the inner spiral trapezoidal teeth 8-1 of the main shaft nut 8, and the outer spiral trapezoidal teeth 7-3 of the main shaft 7 and the inner spiral trapezoidal teeth 8-1 of the main shaft nut 8 have a pressure block. 10 is the clearance of the design state. When the rack 12 applies axial force to the pressure block 10, the spindle nut 8 and the pressure block 10 cooperate with the spindle nut positioning protrusion 8-2 of the spindle nut 8 and the pressure block positioning hole 10-4 of the pressure block 10, and the spindle nut 8 cannot spirally rise relative to the spindle 7. Then, the pressure block 10 and the spindle nut 8 are restricted by the outer spiral trapezoidal teeth 7-3 of the spindle 7. When the clearance between the adjustment nut 4 and the pressure block 10 is greater than the clearance of the design state of the pressure block 10, the pressure block 10 and the spindle nut 8 can only axially move the distance of the clearance of the design state of the pressure block 10. When the clearance between the adjustment nut 4 and the pressure block 10 is smaller than the clearance between the adjustment nut 4 and the pressure block 10, the pressure block 10 and the spindle nut 8 can only axially move the distance of the clearance of the design state of the pressure block 10. When the clearance of the pressure block 10 is in the designed state, the pressure block 10 and the spindle nut 8 can only axially move the distance of the clearance between the adjustment nut 4 and the pressure block 10; there is a spindle positioning protrusion 7-2 on the spindle 7, and the spindle positioning protrusion 7-2 is matched with the plane needle bearing 6 and the gasket 5 in turn, and the gasket 5 is in contact with the lower plane of the bottom of the adjustment nut 4. The large compression spring 2 is placed between the annular groove of the adjustment nut 4 and the pressure block annular groove 10-1 of the pressure block 10. When the gear 13, the rack 12 or the rack 12 and the pressure block lining 11 are worn, the pressure block 10 is axially moved toward the rack 12 under the force of the large compression spring 2. The spindle 7 moves axially, the pressure block 10 drives the spindle nut 8 to move axially, the spindle nut 8 drives the spindle 7, the plane needle roller bearing 6, and the gasket 5 to move axially, and a gap is generated between the gasket 5 and the lower plane at the bottom of the adjusting nut 4. At this time, the small compression spring 3 provides axial force for the spindle 7, and the spindle 7 produces a rotational upward motion under the action of the axial force, thereby compensating for the wear between the gear 13, the rack 12 or the rack 12, and the pressure block lining 11. The plane needle roller bearing 6 can reduce the friction force when the spindle 7 rotates, so that the preload force of the small compression spring 3 does not need to be too large and the thread lead angle of the spindle nut 8 is reduced, thereby reducing the difficulty of processing the spiral trapezoidal teeth.When the adjustment nut 8 is loose, a gap will also be generated between the gasket 5 and the lower plane at the bottom of the adjustment nut 4. Then the small compression spring 3 provides an axial force for the main shaft 7, and the main shaft 7 produces a rotational upward motion under the action of the axial force, thereby compensating for the loosening of the adjustment nut 4. Regardless of the amount of wear between the gear 13, the rack 12 or the rack 12 and the pressure block lining 11, the main shaft 7 will rotate to a corresponding angle under the action of the small compression spring 3, thereby realizing stepless adjustment of the pressure block gap. After the main shaft nut 8, the small compression spring 3, the main shaft 7 and the pressure block 10 are assembled, the fixing pin 1 cooperates with the main shaft center hole 7-1 of the main shaft 7 and the fixing pin installation groove 10-3 to constrain it to prevent the main shaft 7 from being ejected. After the adjustment nut 8 is finally assembled, the fixing pin 1 is pulled out. The force analysis model of the main shaft 7 under the force of the small compression spring 3 is equivalent to the model of the slider sliding down the inclined plane at a constant speed, such as. Figure 8 As shown, it is a schematic diagram of the main shaft force analysis model, the axial load Fa is the combined force of the small compression spring 3 and the gravity of the main shaft 7, F is the balancing force required to maintain the uniform motion of the main shaft 7, A is the helix angle, and B is the friction angle. When the thread lead angle A is greater than the friction angle B, that is, self-locking will not occur, the main shaft 7 can spirally rise under the action of the small compression spring 3.

[0034] The advantages of the utility model are:

[0035] The utility model can automatically compensate the gear and rack clearance increased by the wear of the parts of the steering machine during use through the mechanical structure, and the compensation is stepless, that is, the compensation is equal to the wear, so that the pressure block clearance is always maintained at the original design state to prevent noise.

[0036] Through the differentiated size design of the spiral trapezoidal teeth of the spindle and the spindle nut, the mating surfaces of the spindle trapezoidal teeth and the spindle nut trapezoidal tooth grooves are parallel, but a symmetrical gap design is adopted to ensure that the gap between the gear and the rack is maintained in the required design state. The spiral trapezoidal teeth have the advantages of high load-bearing capacity, high precision, good wear resistance and stable structure.

[0037] The plane needle roller bearing can optimize the friction force when the spindle rotates, make the automatic compensation response more sensitive, and prevent noise. It can also reduce the preload force of the compression spring and the thread lead angle of the spiral trapezoidal teeth, thereby reducing the difficulty of spiral trapezoidal teeth processing.

[0038] The gasket design can prevent the plane needle bearing from producing uneven indentations on the adjusting nut, ensuring the coaxiality of the product and thus improving the durability of the clamping mechanism.

[0039] The double compression spring design can not only provide greater preload force for the pressure block assembly during gear and rack transmission, but also the large compression spring automatically compensates for the wear of the gear, rack or rack, and pressure block lining. The small compression spring adjusts the meshing amount of the spiral trapezoidal teeth of the main shaft and the main shaft nut, thereby ensuring that the pressure block gap is maintained at the designed state.

Claims

1. A clamping mechanism for steplessly and automatically compensating the clearance between a gear and a rack on a steering machine, comprising an adjusting nut, a clamping block, and a clamping block gasket, characterized in that: The top of the pressing block (10) is connected to one end of the main shaft (7), and the other end of the main shaft (7) is connected to the adjusting nut (4). The fixing pin (1) passes through the adjusting nut (4), the main shaft (7) and the pressing block (10) from top to bottom and are connected. A main shaft nut (8) is sleeved on the outer side of one end of the main shaft (7), and a small compression spring (3) is sleeved on the upper outer side of the main shaft nut (8). A plane needle bearing (6) and a gasket (5) are sleeved on the top of the main shaft (7). A large compression spring (2) is embedded at the bottom of the adjusting nut (4). The bottom of the pressing block (10) is connected to the pressing block gasket (11).

2. The clamping mechanism for steplessly and automatically compensating the clearance between the rack and pinion on a steering machine according to claim 1 is characterized in that: The body of the pressing block (10) is a cylindrical structure, a pressing block annular groove (10-1) is provided at the top of the pressing block (10), and the bottom of the pressing block (10) is an arc-shaped structure; a plurality of sealing ring grooves (10-2) are provided at the outer edge of the body of the pressing block (10), and a sealing ring (9) is embedded in the sealing ring groove (10-2).

3. A clamping mechanism for steplessly and automatically compensating for rack-gear clearance on a steering machine according to claim 1 or 2, characterized in that: A fixing pin installation groove (10-3) connected to the fixing pin (1) is provided at the bottom center of the pressing block annular groove (10-1) at the top of the pressing block (10), and pressing block positioning holes (10-4) connected to the spindle nut (8) are provided on both sides of the fixing pin installation groove (10-3).

4. The clamping mechanism for steplessly and automatically compensating the clearance between the rack and pinion on a steering machine according to claim 1 is characterized in that: The spindle nut (8) is a stepped cylindrical structure, and an inner spiral trapezoidal tooth (8-1) connected to the spindle (7) is provided at the center of the upper cylinder of the spindle nut (8), and a spindle nut positioning protrusion (8-2) connected to the pressure block positioning hole (10-4) of the pressure block (10) is provided at the bottom of the spindle nut (8).

5. The clamping mechanism for steplessly and automatically compensating the clearance between the gear and rack on the steering machine according to claim 1 is characterized in that: The spindle (7) is a bolt structure, a spindle center hole (7-1) connected to the fixing pin (1) is provided at the center of the spindle (7), a spindle positioning protrusion (7-2) is provided at the top of the spindle (7), and an external spiral trapezoidal tooth (7-3) connected to the spindle nut (8) is provided at the bottom of the spindle (7).

6. The clamping mechanism for steplessly and automatically compensating the clearance between the rack and pinion on a steering machine according to claim 1 is characterized in that: The pressing block gasket (11) is an arc-shaped sheet structure, the top of the pressing block gasket (11) is connected to the bottom of the pressing block (10), and the bottom of the pressing block gasket (11) abuts against the rack.

7. The clamping mechanism for steplessly and automatically compensating the clearance between gears and racks on a steering machine according to claim 1 is characterized in that: The gasket (5) is located above the plane needle roller bearing (6), and the gasket (5) and the plane needle roller bearing (6) are sleeved on the main shaft positioning protrusion (7-2) of the main shaft (7).

8. The clamping mechanism for steplessly and automatically compensating the clearance between gears and racks on a steering machine according to claim 1 is characterized in that: The bottom of the adjusting nut (4) is located above the pressing block (10), and a gap is provided between the bottom plane of the adjusting nut (4) and the top plane of the pressing block (10).

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