CN113212544B - Rack pressing device of rack and pinion steering gear and measuring method of meshing clearance - Google Patents

Abstract

The invention discloses a rack pressing device for a rack and pinion steering gear and a method for measuring meshing clearance, wherein the rack pressing device for the rack and pinion steering gear comprises a pressing block cover and a pressing block bottom; It is in arc-shaped contact with the back of the rack, and there is a groove for installing a rubber ring on the contact side of the bottom of the pressure block and the rack to reduce the friction between the metal parts and reduce the wear of the rack pressure block; the pressure block cover cylinder is connected to the pressure block. The center hole at the bottom of the block is connected, and the cover of the pressing block is connected with the steering gear housing by threads. The invention also discloses a device and method for measuring the meshing clearance of the gear rack and pinion of the steering gear. The steering gear is fixed on the bench, the measuring device is located at the top of the bench, and the displacement measuring devices are two laser displacement sensors, which are symmetrical about On both sides of the central axis of the rack, the measuring head passes through the central through hole at the bottom of the pressing block and does not contact the back side of the rack. It has a simple structure, avoids unnecessary wear during measurement, and improves the accuracy of measuring the meshing gap.

Description

Rack pressing device of rack and pinion steering gear and measuring method of meshing clearance

technical field

The invention belongs to the technical field of automobile steering systems, and in particular relates to a rack pressing device for a rack and pinion steering gear, a meshing clearance measuring device and a method for measuring meshing clearance.

Background technique

With the rapid development of society and the improvement of the national economic level, the quality of life has obviously become a factor that people care about more. Compared with the scarcity of cars in the past era, cars have become very popular in today's society and become a necessary means of transportation in people's daily life. The steering system is an important part of the car and is closely related to the driving stability of the car. The steering system mainly includes three subsystems: steering control mechanism, steering gear, and steering transmission mechanism. The function of the steering gear is to appropriately transform the steering torque and steering angle from the steering wheel (mainly deceleration and distance increase), and then output it to the steering rod mechanism, thereby turning the car. There are many types of steering gear, such as rack and pinion type, circulating ball type, worm crank finger type, power steering gear, etc. Rack and pinion steering gear is currently the most commonly used steering gear in automobiles.

In the conventional technology, the pressing device for pressing the rack of the rack and pinion steering gear is usually an integral pressing block structure. The rack is generally directly pressed by the 45° line contact arc-shaped pressing block, and the rack is pressed against the input shaft by the action of the pressing mechanism, thereby realizing the meshing of the gear and rack. This device is easy to cause wear of the gear rack, and it is difficult to measure the meshing clearance of the steering gear. In the past, when measuring the meshing clearance of the rack and pinion, the measuring mechanism often used a dial indicator or a dial indicator. Meshing clearance; in some measurement methods, the pressing block is opened, and the measuring head is in contact with the back end of the rack to measure the meshing clearance of the rack and pinion. When the rack and pinion rotates, the measuring head will slide left and right, which affects the measurement accuracy of the gap.

SUMMARY OF THE INVENTION

In order to solve the deficiencies in the prior art, the present invention provides a rack pressing device for a rack and pinion steering gear, a meshing gap measuring device and a method for measuring the meshing gap, which can reduce the gap between the rack and the pressure. The friction between the blocks is convenient to measure the meshing clearance of the rack and pinion.

The technical scheme adopted in the present invention is as follows:

A rack pressing device for a rack and pinion steering gear, including a pressure block cover and a pressure block bottom; the pressure block cover includes a cover body part, and a cylindrical body part is coaxially arranged at the center of the cover body part, and the diameter of the cover body part is larger than the diameter of the cylinder part; the bottom of the cylinder part is an inwardly concave arc groove; and the side wall surface of the cover part is threaded;

The outside of the bottom of the pressing block is cylindrical, and a through hole is axially opened in the central position of the bottom of the pressing block, and the diameter of the through hole is matched with the diameter of the cylinder part; Removable connection between covers; the bottom of the pressure block is an inwardly concave arc groove; the arc groove at the bottom of the pressure block and the arc groove at the bottom of the cylinder part are on the same arc, and the arc Fitted with the outer arc of the rack to compress the rack.

Further, grooves are symmetrically arranged on the arc groove at the bottom of the pressure block, and a rubber lining strip is installed in the groove. The rubber lining strip can reduce the friction when the pressure block bottom is in direct contact with the rack and reduce the tooth The rod is worn out, and the relative position of the bottom of the pressure block and the rack is limited.

Further, a plurality of connecting holes are opened in the cover part, and a plurality of screw holes are opened on the upper surface of the bottom of the pressing block, and the screw holes correspond to the connecting holes of the cover part one-to-one;

Further, a plurality of second annular grooves are provided on the side wall surface of the cylinder part, and a second rubber ring is installed in the second annular groove; Positional stability of the device during normal compression work.

Further, a plurality of first annular grooves are provided on the side wall surface of the bottom of the pressing block, and a first rubber ring is installed in the first annular groove. The first rubber ring can stabilize the position of the pressing device in the steering gear housing and prevent pressure The block bottom and steering gear housing are severely worn.

Further, a rubber lining is also installed between the bottom of the pressure block and the cover of the pressure block.

A rack and pinion clearance measuring device for a rack and pinion steering gear, comprising a bench, a set of fixing frames is fixedly arranged on the upper surface of the bench, each set of fixing frames comprises two symmetrically distributed support frames, each support frame A displacement measuring device is installed on the top of the device; the displacement measuring device adopts a laser displacement sensor or a grating displacement sensor; a support unit is arranged between the two support frames, and the support unit is composed of two symmetrically distributed U-shaped brackets; The bottom is fixedly mounted on the stand.

Further, when measuring the rack and pinion clearance of the rack and pinion steering gear, it is only necessary to open the pressure block cover, and insert the measuring head of each displacement measuring device into the through hole, and use the displacement measuring device to detect the gear and The displacement between the two during the rotation and meshing of the rack is the meshing gap between the two.

A method for measuring the clearance of a rack and pinion for a rack and pinion steering gear, comprising the following steps:

Step 1. Fix the steering gear on the U-shaped frame of the bench;

Step 2. When measuring the gap between the rack and pinion, open the cover of the pressure block, pass the measuring head of the displacement measuring device through the through hole at the bottom of the pressure block, and place them on both sides of the rack axis, close to the rack but not in contact. Rack surface to prevent wear when the measuring head contacts the rack surface;

再将齿轮和齿条反向转动，反转时，两个位移测量装置再次检测到位移信号分别是y1和y2，将得到的位移值再次取平均值

再将两次得到的位移平均值x和y取平均值，将x和y的平均值作为最终的间隙值。Step 3. Rotate from the initial contact position of the gear and the rack to the final contact position. During the rotation and meshing of the gear and the rack, the two displacement measuring devices measure the displacement generated between the gear and the rack, which is the difference between the two. Meshing clearance; during forward rotation, the displacement signals generated by the two displacement measuring devices are x1 and x2, respectively, and the displacement values obtained by the two displacement measuring devices are averaged.

Then rotate the gear and rack in the reverse direction. When the reverse is reversed, the two displacement measuring devices detect that the displacement signals are y1 and y2 respectively, and the obtained displacement values are averaged again.

Then take the mean value x and y of the displacement obtained twice, and take the mean value of x and y as the final gap value.

Beneficial effects of the present invention:

1. The rack pressing device designed by the present invention includes two parts: the pressure block cover and the pressure block bottom. When measuring, open the pressure block cover, and directly measure the displacement generated between the rack and the gear by the displacement measuring device. It is more direct and accurate to measure the meshing clearance indirectly;

2. Because the arc groove on the bottom surface of the pressure block is adapted to the size of the rack, and is equipped with a rubber lining strip, the friction is reduced and the wear between the pressure block and the rack is reduced;

3. The gap measurement device adopts laser displacement sensor or grating displacement sensor, which does not need to contact the back of the rack, which improves the accuracy of the measurement value and avoids unnecessary wear caused by the traditional contact rack measurement.

Description of drawings

The present invention will be further explained below in conjunction with the accompanying drawings and specific embodiments;

1 is a cross-sectional structural view of a rack and pinion steering gear with a rack pressing device in an embodiment of the present invention;

Figure 2 is a schematic structural diagram of a rack pressing device;

Fig. 3 is the structural schematic diagram of the pressing block cover in Fig. 2;

Fig. 4 is the structural representation of the bottom of the pressing block in Fig. 2;

FIG. 5 is a schematic structural diagram of the bottom of the pressing block in FIG. 4;

FIG. 6 is a schematic diagram of the structure of the rubber lining in FIG. 2

Fig. 7 is a schematic diagram of the structure of the fastening screw in the pressing device in Fig. 1;

8 is a schematic structural diagram of a gap measurement device;

The marks in the above picture are: 1. Pressure block cover, 2. Pressure block bottom, 3. First annular groove, 4. Fastening screw, 5. Rubber lining, 6. Rack, 7, Gear, 8 , steering gear housing, 9, through hole, 10, second annular groove, 11, first rubber ring, 12, second rubber ring, 13, stand, 14, U-shaped bracket, 15, displacement measuring device, 16 , Support frame, 17, screw hole, 18, groove, 19, column part, 20, support frame through hole.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

As shown in Figure 1, the rack and pinion steering gear is a cross-sectional structure diagram. The rack pressing device for the rack and pinion steering gear designed in this application includes a pressure block cover 1 and a pressure block bottom 2; as shown in Figure 2 The pressure block cover 1 shown in and 3 includes a cover body part and a column body part 19. Both the cover body part and the column body part 19 are cylinders, but the diameter of the cover body part is larger than the diameter of the column body part 19, and the column body part 19 It is coaxially arranged at the bottom of the cover part, and the whole is like an umbrella. A plurality of connection holes are opened in the cover part, and threads 001 are opened on the side wall surface of the cover part, and the pressure block cover 1 is connected with the steering gear housing 8 by screws. A plurality of second annular grooves 10 are provided on the side wall surface of the cylindrical portion 19, and a second rubber ring 12 is installed in the second annular groove 10. The second rubber ring 12 can make the pressure block cover 1 and the pressure block bottom 2 tightly In combination, the positional stability of the pressing device during normal pressing work is ensured. The bottom of the cylindrical portion 19 is an inwardly concave arc groove.

As shown in Figures 4, 5 and 7, the outside of the pressure block bottom 2 is cylindrical, and a plurality of first annular grooves 3 are provided on the side wall surface of the pressure block bottom 2, and a first rubber ring 11 is installed in the first annular groove 3, The first rubber ring 11 can stabilize the position of the pressing device in the steering gear housing, and prevent the pressing block bottom 2 and the housing 8 from being severely worn. A through hole 9 is axially opened in the central position of the pressing block bottom 2 . The diameter of the through hole 9 matches the diameter of the cylinder part 19 to ensure that the cylinder part 19 penetrates into the through hole 9 during installation. A plurality of screw holes 17 are provided on the upper surface of the pressing block bottom 2, and the screw holes 17 correspond to the connecting holes of the cover part one by one; The connection between the pressure block covers 1. The bottom of the pressure block bottom 2 is an inwardly concave arc groove, and the arc groove at the bottom of the pressure block bottom 2 and the arc groove at the bottom of the cylinder part 19 are on the same arc, and the arc and the rack 6 The outer arcs of the racks fit together to compress the rack 6. A groove 18 as shown in FIG. 5 is symmetrically arranged on the arc groove at the bottom of the pressure block bottom 2, and a rubber lining strip is installed in the groove 18. The rubber lining strip can reduce the pressure between the pressure block bottom 2 and the rack 6. The friction during direct contact reduces the wear of the rack and limits the relative position of the pressing block device and the rack 6 .

As shown in Figure 6, a rubber lining 5 is also installed between the pressure block bottom 2 and the pressure block cover 1, and a hole that is adapted to the size and position of the through hole 9 is opened in the center of the rubber lining 5. There are also screw holes that are compatible with the size and position of the four screw holes 17 of the pressure block bottom 2. The rubber lining 5 can fasten the pressure block cover 1 and the pressure block bottom 2 to prevent the pressure block cover 1 and the pressure block bottom. 2 Wear in direct contact.

Based on the above rack pressing device, the present application also proposes a rack and pinion clearance measuring device for a rack and pinion steering gear, as shown in FIG. Fixed frame, each set of fixed frames includes two symmetrically distributed support frames 16, and a displacement measuring device 15 is installed on the top of each support frame 16; the displacement measuring device 15 adopts a laser displacement sensor or a grating displacement sensor; each support frame The side wall surface of 16 is provided with a support frame through hole 20 . When measuring the rack and pinion clearance of the rack and pinion steering gear, it is only necessary to open the pressure block cover 1, and insert the measuring head of each displacement measuring device 15 into the through hole 9, and use the displacement measuring device 15 to detect The displacement generated between the gear 7 and the rack 6 during the rotational meshing process is the meshing gap between the two. The rack and pinion clearance measuring device designed in this application does not need to be in contact with the rack 6; and the extension lines of the two measuring heads are on both sides of the axis of the rack 6, eliminating the need for a single measuring head to measure when the rack and pinion rotates left and right in the traditional technology. error caused by the gap.

Based on the above-mentioned rack and pinion clearance measuring device for a rack and pinion steering gear, the present application also proposes a rack and pinion clearance measuring method for a rack and pinion steering gear, comprising the following steps:

Step 1. Fix the steering gear housing 8 on the U-shaped frame 14 of the platform 13 and pass through the support frame through hole 20 on the support frame 16;

Step 2. When measuring the gap between the rack and pinion, open the pressure block cover 1, pass the measuring head of the displacement measuring device 15 through the through hole 9 of the pressure block bottom 2, and arrange them on both sides of the axis of the rack 6 respectively. The measuring device 15 can detect the distance between the measuring head and the rack 6, so it can be close to the rack 6 but not contact the surface of the rack, preventing the wear caused when the measuring head contacts the surface of the rack 6;

再将齿轮7和齿条6反向转动，反转时，两个位移测量装置15再次检测到位移信号分别是y1和y2，将得到的位移值再次取平均值

再将两次得到的位移平均值x和y取平均值，将x和y的平均值作为最终的间隙值。传统技术测量啮合间隙时，往往将千分表之间直接齿条6背，转动齿轮、与齿条6时，千分表的测量头往往会发生摆动，采用本发明中的间隙测量装置及方法式时，避免了这样的问题，大大提高了传统间隙测量的精度。Step 3. Use a torque wrench to rotate the rack 6 at one end of the rack 6, from the initial contact position of the gear 7 and the rack 6 to the final contact position. During the rotation and meshing of the gear 7 and the rack 6, the displacement measuring device 15 measures the gear. The displacement generated between 7 and the rack 6 is the meshing gap between the two; during forward rotation, the two displacement measuring devices 15 both detect the displacement and generate displacement signals which are x1 and x2 respectively, and the two displacement measuring devices 15 The resulting displacement values are averaged

Then rotate the gear 7 and the rack 6 in the reverse direction. When the reverse is reversed, the two displacement measuring devices 15 detect that the displacement signals are y1 and y2 respectively, and the obtained displacement values are averaged again.

Then take the average value of the displacement average x and y obtained twice, and take the average value of x and y as the final gap value. When measuring the meshing gap with the traditional technology, the dial indicator is often placed directly behind the rack 6, and when the gear and the rack 6 are rotated, the measuring head of the dial indicator tends to swing. The gap measuring device and method in the present invention are used. When the formula is used, such a problem is avoided, and the accuracy of the traditional gap measurement is greatly improved.

The above embodiments are only used to illustrate the design ideas and features of the present invention, and the purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly, and the protection scope of the present invention is not limited to the above embodiments. Therefore, all equivalent changes or modifications made according to the principles and design ideas disclosed in the present invention fall within the protection scope of the present invention.

Claims (9)

1. A rack pressing device for a rack-and-pinion steering gear, characterized in that it comprises a pressure block cover (1) and a pressure block bottom (2); the pressure block cover (1) includes a cover body part, and the cover body A cylindrical body part (19) is coaxially arranged at the center of the part, and the diameter of the cover body part is larger than the diameter of the cylindrical body part (19); the bottom of the cylindrical body part (19) is an inwardly concave arc groove; The side wall surface of the fuselage is threaded (001); The outside of the pressing block bottom (2) is cylindrical, and a through hole (9) is axially opened in the central position of the pressing block bottom (2). and use fasteners to realize the detachable connection between the pressure block bottom (2) and the pressure block cover (1); the bottom of the pressure block bottom (2) is an inwardly concave arc groove; the pressure block bottom ( 2) The camber groove at the bottom and the camber groove at the bottom of the cylinder part (19) are on the same arc, and the arc fits with the outer arc of the rack (6), so as to prevent the rack (19). 6) The pressing effect. 2. The rack pressing device according to claim 1, wherein a groove (18) is symmetrically arranged on the arc groove at the bottom of the pressing block (2), and a rubber is installed in the groove (18). The material of the lining strip and the rubber lining strip can reduce the friction when the pressure block bottom (2) and the rack (6) are in direct contact, reduce the wear of the rack, and have a good effect on the contact between the pressure block bottom (2) and the rack (6). The relative position is limited. 3. The rack pressing device according to claim 1, wherein a plurality of connecting holes are opened in the cover part, and a plurality of screw holes (17) are opened on the upper surface of the pressing block bottom (2), The screw holes (17) correspond one-to-one with the connecting holes of the cover part. 4. The rack pressing device according to claim 1, wherein a plurality of second annular grooves (10) are provided on the side wall surface of the cylindrical portion (19), and the second annular groove (10) A second rubber ring (12) is installed inside; the second rubber ring (12) can make the pressure block cover (1) and the pressure block bottom (2) tightly combined, so as to ensure the positional stability of the pressing device during normal pressing work. 5 . The rack pressing device according to claim 1 , wherein a plurality of first annular grooves ( 3 ) are provided on the side wall surface of the pressing block bottom ( 2 ), and the first annular groove ( 3 ) A first rubber ring (11) is installed inside, and the first rubber ring (11) can stabilize the position of the pressing device in the steering gear housing (8) and prevent the pressure block bottom (2) from occurring with the steering gear housing (8). Severe wear and tear. 6 . The rack pressing device according to claim 1 , wherein a rubber lining ( 5 ) is also installed between the pressing block bottom ( 2 ) and the pressing block cover ( 1 ). 7 . 7. A rack and pinion clearance measuring device for a rack and pinion steering gear, which is suitable for the rack pressing device according to claim 1, characterized in that it comprises a bench (13), and the bench (13) is A set of fixed frames is fixedly arranged on the upper surface, each set of fixed frames includes two symmetrically distributed support frames (16), and a displacement measurement device (15) is installed on the top of each support frame (16); the displacement measurement device (15) ) using a laser displacement sensor or a grating displacement sensor; a supporting unit is arranged between the two supporting frames (16), and the supporting unit is composed of two symmetrically distributed U-shaped brackets (14); the bottom of the U-shaped bracket (14) is fixedly installed on the stand (13). 8. The rack and pinion clearance measuring device according to claim 7, characterized in that, when measuring the rack and pinion clearance of the rack and pinion steering gear, it is only necessary to open the pressing block cover (1), and set each The measuring heads of each displacement measuring device (15) protrude from the through hole (9), and the displacement measuring device (15) is used to detect the displacement generated between the gear (7) and the rack (6) during the rotation and meshing process of the two, That is the meshing gap between the two. 9. A rack and pinion clearance measuring method based on the rack and pinion clearance measuring device according to claim 8, characterized in that, comprising the steps of: Step 1. Fix the steering gear housing (8) on the U-shaped bracket (14) of the platform (13); Step 2. When measuring the gap between the rack and pinion, open the pressure block cover (1), pass the measuring head of the displacement measuring device (15) through the through hole (9) of the pressure block bottom (2), and place them on the rack respectively. (6) The two sides of the axis are arranged, close to the rack (6) but not in contact with the surface of the rack, to prevent the wear caused when the measuring head contacts the surface of the rack (6); Step 3. From the initial contact position of the gear (7) and the rack (6) to the final contact position, during the rotation and meshing of the gear (7) and the rack (6), the two displacement measuring devices (15) measure the gear The displacement generated between (7) and the rack (6) is the meshing gap between the two; during forward rotation, the two displacement measuring devices (15) detect the displacement and generate displacement signals which are x1 and x2, respectively. The displacement values obtained by the displacement measuring devices (15) are averaged

Then the gear (7) and the rack (6) are rotated in the reverse direction. When the reverse is reversed, the two displacement measuring devices (15) again detect that the displacement signals are y1 and y2 respectively, and the obtained displacement values are averaged again.

Then take the average value of the displacement average x and y obtained twice, and take the average value of x and y as the final gap value.

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