Device and method for measuring symmetry and verticality of gear shaft hole and slotted shaft hole of differential housing

Abstract

The invention discloses a device and a method for measuring the symmetry and verticality of a gear shaft hole and a straight shaft hole of a differential housing, and relates to the technical field of form and position tolerance measurement. The invention solves the problem that an existing differential housing inspection tool cannot perform online detection of the symmetry and verticality of a gear shaft hole and a straight shaft hole of a differential housing in real time. The invention comprises a spindle assembly and a V-shaped positioning member; the spindle assembly comprises a gear shaft hole positioning spindle and a straight shaft hole positioning spindle; the V-shaped positioning member comprises a fixed V-shaped positioning member and a floating V-shaped member; the gear shaft hole positioning spindle is inserted into the gear shaft hole of the differential housing for positioning, and the straight shaft hole positioning spindle is inserted into the following circular hole of the gear shaft hole positioning spindle and then positioned with the straight shaft hole of the differential housing; the differential housing with the spindle assembly inserted into the V-shaped positioning member, and the display values ​​of the symmetry measuring micrometer and the verticality measuring micrometer are observed to realize the measurement of the symmetry and verticality of the gear shaft hole and the straight shaft hole of the differential housing. The invention improves the detection efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of form and position tolerance measurement, and in particular to a device and method for measuring the symmetry and perpendicularity of a differential housing gear shaft hole and a slotted shaft hole (planetary gear positioning shaft hole). Background Art

[0002] The traditional form of hole position measurement form and position tolerance online inspection fixture (hole position gauge) is to make holes with the same spatial position of the product and contain the product in the inspection fixture structure. When measuring, the product is placed in it. The spatial position form and position tolerance and dimensional accuracy of the online inspection fixture are designed according to one tenth of the product accuracy form and position tolerance and dimensional tolerance. The diameter size of the hole measurement pin is based on the form and position tolerance size, and the influence of the manufacturing accuracy of the inspection fixture itself must also be considered. After the above-mentioned influencing factors are calculated, the reduced diameter size is calculated. Only in this way can the designed and processed measuring pin detect whether the product is qualified or unqualified. The inspected part must be After the hole size is qualified, the measuring pin with a reduced diameter according to the form and position tolerance size is inserted into the measured hole. The product part that can be inserted is a qualified part, otherwise it is an unqualified part. The traditional form of hole form and position tolerance online inspection fixture is easily affected by the structure, form and position tolerance size (>0.1 mm), size tolerance size (>0.5 mm) and human factors. It is illegal to use when the size and form and position tolerance accuracy of the product part is less than 0.1 mm. In other words, the traditional form of hole form and position tolerance online inspection fixture can no longer be applied to the inspection of today's new automotive product parts.

[0003] At present, the shape and position tolerance accuracy requirements for the gear shaft hole and the slotted shaft hole of the differential shaft system are very high, such as Figure 1 As shown, Figure 1This is a schematic diagram of the differential housing structure. The symmetry accuracy of the gear shaft hole and the slotted shaft hole is required to be 0.05 mm, that is, the maximum deviation of the center lines of the two holes cannot exceed 0.025 mm. The verticality is 0.08 mm, that is, the verticality of the slotted shaft hole to the center line of the gear shaft hole over the entire length is 0.08 mm. Because the center line of the hole is required to be used as the measurement reference, the hole itself has a dimensional tolerance, and a self-centering mandrel is required to locate the measurement hole. The online inspection fixture requires accurate measurement and convenient verticality. Since it is difficult to design a detection device with this function, a detection device with the above function has not been developed yet. In the existing technical application, three-coordinate measurement is adopted. The differential housing is produced and processed in a large-scale production mode with a very fast production rhythm. According to the modern large-scale production mode, the first piece processed in each shift must be inspected, and three pieces must be sampled during the four-hour processing. If there is no online inspection tool and three-coordinate measurement is adopted, the production of the differential housing will not be able to proceed normally. The three-coordinate is generally installed in the precision measurement room. It takes at least 20 minutes to send each piece for inspection, which seriously affects the production efficiency. Therefore, the development of an online inspection tool (accurately reading the value) that can quickly and accurately detect the symmetry and verticality of the gear shaft hole and the slotted shaft hole of the differential housing is the only option at present. Summary of the invention

[0004] The present invention aims to solve the problem that the existing differential case inspection tool cannot perform online inspection on the symmetry and perpendicularity of the differential case gear shaft hole and the straight shaft hole in real time, and provides a device and method for measuring the symmetry and perpendicularity of the differential case gear shaft hole and the straight shaft hole.

[0005] A device for measuring the symmetry and verticality of a gear shaft hole and a slotted shaft hole of a differential housing, the device comprising a spindle assembly and a V-shaped positioning member; the spindle assembly comprises a gear shaft hole positioning spindle and a slotted shaft hole positioning spindle; the V-shaped positioning member comprises a fixed V-shaped positioning member and a floating V-shaped member;

[0006] The floating V-shaped member is provided with a micrometer for measuring symmetry and a micrometer for measuring verticality;

[0007] The fixed V-shaped positioning member is fixed on the bottom plate and is used to position the gear shaft hole and the positioning spindle;

[0008] The floating V-shaped member is connected to the positioning shaft assembly installed on the bottom plate, and can move up and down or swing on the bottom plate to position the straight-axis hole positioning spindle;

[0009] Insert the gear shaft hole positioning spindle into the gear shaft hole of the differential case for positioning, insert the slotted shaft hole positioning spindle into the round hole of the gear shaft hole positioning spindle and then position it with the slotted shaft hole of the differential case;

[0010] Place the differential case with the spindle assembly into the V-shaped positioning piece, observe the displayed values ​​of the symmetry micrometer and the verticality micrometer, and measure the symmetry and verticality of the gear shaft hole and the slotted shaft hole of the differential case.

[0011] The present invention also provides a method for measuring the symmetry and perpendicularity of a gear shaft hole of a differential case and a straight shaft hole. The method is implemented by a device for measuring the symmetry and perpendicularity of a gear shaft hole of a differential case and a straight shaft hole. The method is implemented by the following steps:

[0012] Step 1: Position the gear shaft hole positioning spindle and the gear shaft hole of the differential case; pass the slotted shaft hole positioning spindle through the circular hole of the gear shaft hole positioning spindle and position it with the slotted shaft hole of the differential case;

[0013] Step 2: Place the positioning surfaces at both ends of the gear shaft hole positioning spindle on the fixed V-shaped positioning piece, and place the slotted shaft hole positioning spindle on the floating V-shaped piece;

[0014] Step 3: Set the symmetry micrometer and the verticality micrometer to zero, then remove the differential housing, rotate it 180° along the axial direction of the lower gear shaft hole and put it back into the V-shaped positioning piece. The change value of the symmetry micrometer is the symmetry, and the change value of the verticality micrometer corresponds to 2 times the verticality.

[0015] Beneficial effects of the invention: The device for measuring the symmetry and verticality of the differential housing gear shaft hole and the slotted shaft hole of the invention adopts a gapless spindle for positioning, and the positioning accuracy is higher than the three-coordinate drilling point accuracy, and the repeated measurement accuracy is 1 to 2 microns. The device is easy to operate, and the display of symmetry and verticality is intuitive.

[0016] The measuring device of the present invention, after the gear shaft hole positioning spindle and the slotted shaft hole positioning spindle are installed in the differential housing, the positioning surfaces at both ends of the gear shaft hole positioning spindle are placed on the fixed V-shaped positioning piece of the online inspection fixture, and the slotted shaft hole positioning spindle is placed on the floating V-shaped piece. At this time, the floating V-shaped positioning shaft of the differential housing changes in height and angle relative to the positioning sleeve and the base plate under the action of gravity, the micrometer for measuring symmetry and the micrometer for measuring verticality are cleared, and then the differential housing with the spindle assembly installed is removed and rotated 180 degrees along the gear shaft hole axis and reinserted. At this time, the change value of the micrometer for measuring symmetry corresponds to the symmetry, and the change value of the micrometer for measuring verticality corresponds to twice the verticality, and the distance between the measuring point of the micrometer for measuring verticality and the center of the floating V-shaped piece is the length of the slotted shaft hole.

[0017] The measuring device of the present invention is designed with a self-centering spindle to eliminate the influence of the gap during the spindle positioning process. Different spindle structures are designed according to different positioning positions and different purposes. In order to solve the problem between the shaft diameter, hole diameter and bead bearing when the positioning spindle of the straight shaft hole penetrates the straight shaft hole, that is, when the front end of the positioning spindle begins to penetrate the straight shaft hole, the front end bead bearing participates in the spindle centering, and there is a pure rolling displacement between the positioning spindle, the straight shaft hole and the bead bearing sleeve. Therefore, the rear end bead bearing sleeve of the positioning spindle is linked to the front end bead bearing sleeve positioning spindle, that is, a double-stage bead bearing sleeve linkage positioning spindle is realized.

[0018] The method for measuring the symmetry and perpendicularity of a differential case gear shaft hole and a slotted shaft hole of the present invention can realize real-time online detection and accurately read the values ​​of symmetry and perpendicularity, thereby improving detection accuracy and detection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of the differential housing structure;

[0020] Figure 2 It is a schematic structural diagram of the device for measuring the symmetry and perpendicularity of the differential case gear shaft hole and the slotted shaft hole of the present invention;

[0021] Figure 3 It is a schematic diagram of the installation position of the micrometer for measuring symmetry in the device for measuring symmetry and perpendicularity of the gear shaft hole and the slotted shaft hole of the differential case of the present invention;

[0022] Figure 4 It is a schematic diagram of the installation position of the micrometer for measuring perpendicularity in the device for measuring the symmetry and perpendicularity of the gear shaft hole and the slotted shaft hole of the differential case of the present invention;

[0023] Figure 5 A front view of the spindle structure for positioning the gear shaft hole;

[0024] Figure 6 for Figure 5 A top view of

[0025] Figure 7 It is a schematic diagram of the structure of the positioning spindle with a straight-axis hole; that is, a schematic diagram of the contact between the double-section bead bearing sleeve and the limit sleeve;

[0026] Figure 8 It is a schematic diagram of the structure of the positioning spindle of the straight-axis hole; that is, a schematic diagram of the contact between the double-section bead bearing sleeve and the limit handle;

[0027] Fig. 9 It is a schematic diagram of the gear shaft hole positioning mandrel after it is inserted into the gear shaft hole for positioning and then inserted into the slotted shaft hole for positioning mandrel;

[0028] Fig.10 A schematic diagram of the spindle assembly after positioning the differential housing;

[0029] Fig.11 The schematic diagram of the gear shaft hole centerline and the slotted shaft hole centerline offset upward when measuring symmetry;

[0030] Fig.12 This is the schematic diagram when the center line of the gear shaft hole and the center line of the slotted shaft hole are offset downward.

[0031] In the figure, 1, support leg, 2, bottom plate, 3, support plate, 4, fixed V-shaped positioning piece, 5, positioning sleeve, 6, fastening screw, 7, V-shaped positioning shaft, 8, top screw, 9, floating V-shaped piece, 10, limit pin, 11, ball bearing, 12, pin, 13, spring, 14, gear shaft hole positioning spindle, 14-1, spindle body, 14-2, positioning sleeve, 14-3, cage, 14-4, ball, 14 -5, pin, 14-6, locking nut, 15, micrometer for measuring verticality, 16, micrometer seat for measuring verticality, 17, positioning spindle for slotted shaft hole, 17-1, positioning spindle body, 17-2, positioning pin, 17-3, limit sleeve, 17-4, double-section ball bearing sleeve, 17-5, limit handle, 18, micrometer seat for measuring symmetry, 19, micrometer for measuring symmetry, 20, measuring block. DETAILED DESCRIPTION

[0032] Specific implementation method 1. Combination Figures 1 to 10 The present embodiment is described, the differential case gear shaft hole and the straight shaft hole symmetry, verticality measuring device, the differential case gear shaft hole and the straight shaft hole symmetry, verticality directly determines the performance of the differential, so it has very high requirements for symmetry and verticality, Figure 1 In the differential case, the gear shaft hole size tolerance is 0.025 mm, the slotted shaft hole is 0.021 mm, the symmetry tolerance is 0.05 mm, and the verticality tolerance is 0.08 mm. In order to accurately measure the form and position tolerances, the spindle used when measuring the gear shaft hole and the slotted shaft hole should have no gap. Therefore, a self-centering spindle must be used to eliminate the influence of the gap during the spindle positioning process. Different spindle structures are designed according to different positioning positions and different purposes. The device includes a spindle assembly and two sets of V-shaped positioning parts; the spindle assembly includes a gear shaft hole positioning spindle 14 and a slotted shaft hole positioning spindle 17;

[0033] The two groups of V-shaped positioning members include a group of fixed V-shaped positioning members 4 and another group of floating V-shaped members 9. A micrometer 19 for measuring symmetry and a micrometer 15 for measuring verticality are installed at the bottom of the floating V-shaped members 9 through a measuring block 20.

[0034] The fixed V-shaped positioning member 4 is fixed on the base plate 2 through the support plate 3, and is used to position the gear shaft hole positioning spindle 14; the floating V-shaped member 9, the floating V-shaped member 9 is connected to the positioning shaft assembly installed on the base plate 2, and the floating V-shaped member 9 can be moved up and down on the base plate 2, and can also be swung within a certain angle range (the certain angle range can be set according to actual needs), and is used to position the straight shaft hole positioning spindle 17.

[0035] Insert the gear shaft hole positioning spindle 14 into the gear shaft hole for positioning, insert the straight shaft hole positioning spindle 17 into the round hole of the gear shaft hole positioning spindle 14 and then position it with the straight shaft hole;

[0036] Place the differential housing with the spindle assembly into the V-shaped positioning piece, observe the display values ​​of the micrometer 19 for measuring symmetry and the micrometer 15 for measuring verticality, and realize the measurement of symmetry and verticality.

[0037] Combination Figures 2 to 4 To explain this embodiment, in this embodiment, the positioning shaft assembly includes a positioning sleeve 5, a fastening screw 6, a floating V-shaped positioning shaft 7, a top screw 8, a limit pin 10, a ball bearing 11, a pin 12 and a spring 13;

[0038] The floating V-shaped part 9 is tightly connected to the floating V-shaped positioning shaft 7, and the floating V-shaped part 9 is perpendicular to the axis of the floating V-shaped positioning shaft 7. The positioning sleeve 5 is fixed on the base plate 2 by a fastening screw 6. The floating V-shaped positioning shaft 7 and the hole of the positioning sleeve 5 are rollingly connected without gaps through a dense ball bearing 11. In order to limit the movement or rotation between the floating V-shaped positioning shaft 7 and the positioning sleeve 5, the positioning sleeve 5 is processed with a pin hole, and the floating V-shaped positioning shaft 7 is processed with a following circular hole. The limit pin 10 passes through the pin hole at the lower end of the positioning sleeve 5 and is connected with the following circular hole at the lower end of the floating V-shaped positioning shaft 7. The radius of the following circular hole is larger than the radius of the limit pin 10, so the floating V-shaped positioning shaft 7 can move axially relative to the positioning sleeve 5, and can also swing within a certain angle range. The axial up and down movement is exactly what is needed when measuring symmetry, and the rotation within a certain angle is exactly what is needed when measuring verticality. The lower end of the pin 12 is pressed against the limit pin 10, the spring 13 is pressed against the upper end surface of the pin 12, and the top screw 8 is pressed against the upper end of the spring 13. Under the action of the spring force, the floating V-shaped positioning shaft 7 is lifted upward until the floating V-shaped positioning shaft 7 is pressed against the limit pin 10 along the arc of the lower end of the circular hole. When the floating V-shaped part 9 is subjected to force, the floating V-shaped positioning shaft 7 can move downward and rotate.

[0039] In this embodiment, a measuring block 20 is installed at the bottom of the floating V-shaped member 9, and the symmetry measuring micrometer 19 is installed on the symmetry measuring micrometer base 18 on the base plate 2, and the symmetry measuring micrometer base 18 is installed on the measuring block 20 on the floating V-shaped member 9 through lever measurement; the verticality measuring micrometer 15 is installed on the verticality measuring micrometer base 16 on the base plate 2, wherein the measuring point of the verticality measuring micrometer 15 is on the measuring block 20 installed on the floating V-shaped member 9, and the distance between the measuring point and the center of the floating V-shaped member 9 is equal to the length of the straight-axis hole of the differential housing.

[0040] Combination Figure 5 and Figure 6 To explain this embodiment, Figure 5 and Figure 6 The present invention is a structural schematic diagram of a gear shaft hole positioning spindle 14, which includes a spindle body 14-1, a circular hole is provided at the center of the spindle body 14-1, and two pin holes with a diameter larger than that of a pin 14-5 are provided on the spindle body 14-1, a double-row ball structure is provided on the spindle body 14-1, and locking nuts 14-6 are installed at both ends of the spindle body 14-1; the double-row ball structure is composed of a positioning sleeve 14-2, a retaining frame 14-3, a ball 14-4 and a pin 14-5; the function of the pin 14-5 is to limit the axial movement of the positioning sleeve 14-2 on the spindle body 14-1, so as to ensure that the maximum distance of the gap between the two retaining frames 14-3 installed on the spindle body 14-1 and the positioning sleeve 14-2 is smaller than the diameter of the ball 14-4, so as to ensure that the ball 14-4 does not fall out in a relaxed state. When locking, the locking nut 14-6 can push the positioning sleeve 14-2 toward the direction of the ball 14-4. Because the spindle body 14-1 and the positioning sleeve 14-2 have a 45° angle surface where the ball is placed, the locking nut 14-6 pushes toward the positioning sleeve 14-2, and the positioning sleeve 14-2 then squeezes the ball 14-4 outward and fixes it through the angle surface corresponding to the retaining frame 14-3, so that the diameter of the gear shaft hole positioning spindle 14 becomes larger until it is positioned with the gear shaft hole.

[0041] In this embodiment, the gear shaft hole positioning spindle 14 adopts a double-row bead structure to center the gear shaft hole. After the gear shaft hole positioning spindle 14 is positioned, it can achieve centering and prevent axial movement. Both ends of the gear shaft hole positioning spindle 14 are positioning sleeves 14-2 with the same diameter and concentric with the spindle, ensuring operability and stability and reliability during the measurement process.

[0042] In this embodiment, the diameter of the slotted shaft hole positioning spindle 17 is relatively small, generally between 17.5-22 mm. Considering the centering structure of the slotted shaft hole, the two ends of the positioning spindle must have diameter dimensions to participate in the positioning and measurement requirements. Considering the stability and strength issues, the diameters at both ends are as large as possible, so it adopts a dense bead bearing structure. The slotted shaft holes at both ends of the differential housing are generally 100 to 150 mm long, and a traditional dense bead bearing shaft, shaft and sleeve (hole) structure is adopted. A 100 mm long hole is positioned with a 100 mm long dense bead bearing, and the minimum length of the shaft is 200 mm. The shaft, the ball bearing and the hole can be completely positioned. Considering that the positioning shaft diameter at both ends of the spindle has a certain length, the traditional method is at least 260 mm. In order to solve the problem of shaft diameter, hole diameter and ball bearing when the positioning spindle of the straight-axis hole is inserted into the straight-axis hole, the front end ball bearing participates in the centering of the spindle when the front end of the positioning spindle begins to penetrate into the straight-axis hole. There is a pure rolling displacement between the positioning spindle, the straight-axis hole and the ball bearing sleeve. Then, the rear end ball bearing sleeve of the positioning spindle is designed to link the front end ball bearing sleeve to position the spindle, that is, the double-stage ball bearing sleeve is linked to the positioning spindle. The positioning spindle adopts a stepped shaft structure. When it is first inserted, the balls of the dense bead bearing are at the small diameter shaft diameter position. There is a gap between the dense bead bearing, the positioning spindle, and the slotted shaft hole, and pure rolling cannot be achieved among the three, so it does not participate in positioning. When the rear end dense bead bearing sleeve is inserted into the slotted shaft hole, the rear end dense bead bearing sleeve and the positioning spindle and the slotted shaft hole perform pure rolling motion. At this time, because the front and rear dense bead bearing sleeves are integrated, the rear dense bead bearing sleeve pulls the front dense bead bearing sleeve into the position with large spindle diameter to achieve the positioning and centering effect of the spindle.

[0043] Combination Figure 7 and Figure 8 To explain this embodiment, Figure 7 and Figure 8This is a schematic diagram of the structure of the positioning spindle 17 for a straight shaft hole. The positioning spindle 17 for a straight shaft hole includes a positioning spindle body 17-1, a positioning pin 17-2, a limiting sleeve 17-3, a double-section bead bearing sleeve 17-4 and a limiting handle 17-5. The positioning spindle body 17-1 adopts a stepped shaft, and the limiting sleeve 17-3 is fastened by the positioning pin 17-2 at a position with a small diameter, and the end face has a specified distance from the position with a large diameter. When one end of the double-section bead bearing sleeve 17-4 is pushed to contact the limiting sleeve 17-3, all the balls at the front end of the double-section bead bearing sleeve 17-4 are at a position with a small diameter of the positioning spindle body 17-1. At this time, the gap between the diameter of the positioning spindle body 17-1 and the straight shaft hole is much larger than twice the diameter of the balls. The positioning spindle is inserted into the straight shaft hole in a clearance fit state. When the balls at the rear end of the double-section bead bearing sleeve 17-4 are pushed to contact the straight shaft hole, the positioning spindle body 17-1 with a large diameter is The clearance between the position and the slotted shaft hole is equal to or less than twice the ball diameter, and the ball rolls purely between the positioning spindle body 17-1 and the slotted shaft hole of the differential housing. The moving distance of the double-stage dense bead bearing sleeve 17-4 is half of the relative moving distance between the positioning spindle body 17-1 and the slotted shaft hole of the differential housing. After the movement, the ball at the front end of the double-stage dense bead bearing sleeve 17-4 also moves to the position with a larger diameter of the positioning spindle body 17-1, positioning the other end of the slotted shaft hole of the differential housing.

[0044] Combination Fig. 9 and Fig.10 The present embodiment is described, and the positioning process of the spindle assembly is as follows: first, the gear shaft hole positioning spindle 14 is inserted into the gear shaft hole, and the circular hole in the middle position of the gear shaft hole positioning spindle 14 can be connected with the position of the straight shaft hole, and the locking nuts 14-6 at both ends are locked to tighten the gear shaft hole positioning spindle 14 to center it, and then the straight shaft hole positioning spindle 17 is inserted. When inserting, the double-section bead bearing sleeve 17-4 of the straight shaft hole positioning spindle 17 is pushed onto the front end limiting sleeve 17-3 of the positioning spindle, and the front end ball of the double-section bead bearing sleeve 17-4 falls to the shaft diameter position with a small diameter of the positioning spindle, and the positioning spindle can easily pass through the straight shaft hole until the ball on the rear end bead bearing sleeve contacts the straight shaft hole, and the ball and the positioning spindle and the straight shaft hole perform pure rolling without gap, and the front end of the same bead sleeve is also brought to the shaft diameter position with a large diameter for pure rolling, until the rear end limiting handle 17-5 touches the differential housing, and then the spindle completely positions the hole.

[0045] Specific implementation method 2: Combination Fig.11 and Fig.12 This embodiment is described. This embodiment is a method for measuring symmetry and perpendicularity using the symmetry and perpendicularity measuring device for the gear shaft hole of the differential housing and the slotted shaft hole described in the first embodiment. The specific measurement process is as follows:

[0046] The two groups of V-shaped positioning members in this embodiment, one group of fixed V-shaped positioning members 4 is fixed on the bottom plate, and is used to position the gear shaft hole positioning spindle 14. The other group of floating V-shaped members 9 can be moved up and down on the bottom plate, and can also swing within a certain angle range, and is used to position the straight shaft hole positioning spindle 17. In this way, after the spindle assembly is put on the differential housing, the shaft diameter at both ends of the positioning spindle for positioning the gear shaft hole is positioned and fixed on the fixed V-shaped positioning members 4 on the bottom plate 2, and the shaft diameter at both ends of the positioning spindle for positioning the straight shaft hole is positioned on the other group of floating V-shaped members 9 on the bottom plate, which can be moved up and down, and can also swing within a certain angle range, to ensure that both groups of spindles can contact and position with the two groups of V-shaped members.

[0047] The process of using the symmetry and verticality measuring device for the differential case gear shaft hole and the slotted shaft hole to realize symmetry detection is as follows:

[0048] First, pass the gear shaft hole positioning spindle 14 through the differential case gear shaft hole to position and lock it, then insert the slotted shaft hole positioning spindle and position it, and then place the differential case with the spindle assembly into the V-shaped positioning piece. At this time, measure the height, that is: set the apparent value of the symmetry micrometer 19 to zero, assume that the upward offset between the center line of the gear shaft hole and the center line of the slotted shaft hole is Δ, and then rotate the differential case 180° along the gear shaft axis and place it on the V-shaped positioning piece again. At this time, the offset between the center line of the gear shaft hole and the center line of the slotted shaft hole should be the downward offset Δ, and the apparent value change of the symmetry micrometer 19 is 2Δ, which is the symmetry between the gear shaft hole and the slotted shaft hole of the differential case. This value can be directly used to adjust the equipment coordinate parameters. In theory, half of this value is Δ to adjust the coordinate, and the symmetry between the gear shaft hole and the slotted shaft hole of the processed differential case is 0.

[0049] The process of using the symmetry and perpendicularity measuring device for the differential case gear shaft hole and the slotted shaft hole to detect the perpendicularity is as follows:

[0050] After placing the differential housing with the spindle assembly into the positioning V-shape, measure the rotation amount, that is: set the apparent value of the verticality micrometer 15 to zero, and the measuring point of the verticality micrometer 15 is on the measuring block 20 on the floating V-shaped part 9. The position of the measuring point is equal to the length of the straight-axis hole of the differential housing at a distance from the center line of the floating V-shaped part 9. Then rotate the differential housing 180° along the axial direction of the gear shaft and place it in the positioning V-shape again to see the change in the apparent value of the verticality micrometer 15. This value is twice the verticality value of the gear shaft hole of the differential housing and the straight-axis hole. This value can be directly used to adjust the coordinate parameters of the equipment. In theory, half of this value is used to adjust the coordinates, and the verticality of the gear shaft hole and the straight-axis hole of the processed differential housing is 0.

[0051] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0052] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A device for measuring the symmetry and perpendicularity of a gear shaft hole and a slotted shaft hole of a differential housing, characterized by: The device comprises a spindle assembly and a V-shaped positioning member; the spindle assembly comprises a gear shaft hole positioning spindle (14) and a straight shaft hole positioning spindle (17); the V-shaped positioning member comprises a fixed V-shaped positioning member (4) and a floating V-shaped member (9); The floating V-shaped member (9) is provided with a micrometer (19) for measuring symmetry and a micrometer (15) for measuring verticality; The fixed V-shaped positioning member (4) is fixed on the bottom plate (2) and is used to position the gear shaft hole positioning spindle (14); The floating V-shaped member (9) is connected to a positioning shaft assembly installed on the bottom plate (2) and can move up and down or swing on the bottom plate (2) to position the straight-axis hole positioning spindle (17); The gear shaft hole positioning spindle (14) is inserted into the gear shaft hole of the differential case for positioning, and the straight shaft hole positioning spindle (17) is inserted into the round hole of the gear shaft hole positioning spindle (14) and then positioned with the straight shaft hole of the differential case; The differential housing with the spindle assembly inserted therein is placed in a V-shaped positioning piece, and the displayed values ​​of the symmetry micrometer (19) and the verticality micrometer (15) are observed to measure the symmetry and verticality of the gear shaft hole and the slotted shaft hole of the differential housing.

2. The device for measuring symmetry and perpendicularity of the gear shaft hole and the slotted shaft hole of the differential case according to claim 1, characterized in that: The positioning shaft assembly comprises a positioning sleeve (5), a fastening screw (6), a floating V-shaped positioning shaft (7), a top screw (8), a limit pin (10), a ball bearing (11), a pin (12) and a spring (13); The floating V-shaped member (9) is tightly connected to the floating V-shaped positioning shaft (7), the positioning sleeve (5) is fixed to the base plate (2) by means of a fastening screw (6), the floating V-shaped positioning shaft (7) and the positioning sleeve (5) are connected in a rolling manner without gap by means of a ball bearing (11), the limit pin (10) passes through the pin hole at the lower end of the positioning sleeve (5) and is connected to the lower end of the floating V-shaped positioning shaft (7) along with the circular hole, the lower end of the pin (12) is pressed against the limit pin (10), the spring (13) is pressed against the upper end surface of the pin (12), the top screw (8) is pressed against the upper end of the spring (13), and under the action of the spring force, the floating V-shaped positioning shaft (7) is lifted upward until the floating V-shaped positioning shaft (7) is pressed against the limit pin (10) along the arc at the lower end of the circular hole, and when the floating V-shaped member (9) is subjected to force, the floating V-shaped positioning shaft (7) moves downward and rotates.

3. The device for measuring symmetry and perpendicularity of a gear shaft hole and a straight shaft hole of a differential case according to claim 2, characterized in that: The radius of the circular hole at the lower end of the floating V-shaped positioning shaft (7) is larger than the radius of the limiting pin (10), so that the floating V-shaped positioning shaft (7) can move axially relative to the positioning sleeve (5) and swing within a certain angle range.

4. The device for measuring symmetry and perpendicularity of a gear shaft hole and a straight shaft hole of a differential case according to claim 1, characterized in that: The gear shaft hole positioning spindle (14) comprises a spindle body (14-1), a circular hole is opened at the center of the spindle body (14-1), a double-row bead structure is arranged on the spindle body (14-1), and locking nuts (14-6) are connected to both ends of the spindle body (14-1); The double-row ball structure is composed of a positioning sleeve (14-2), a retaining frame (14-3), a ball (14-4) and a pin (14-5); The pin (14-5) passes through the pin hole on the spindle body (14-1) to limit the axial movement of the positioning sleeve (14-2) on the spindle body (14-1); when the locking nut (14-6) is locked, the positioning sleeve (14-2) is pushed in the direction of the ball (14-4); the spindle body (14-1) and the positioning sleeve (14-2) are provided with a 45° angle surface at the position where the ball (14-4) is placed; the positioning sleeve (14-2) extrude the ball (14-4) outward and fixes it through the retaining frame (14-3); the diameter of the gear shaft hole positioning spindle (14) increases until it is positioned with the gear shaft hole.

5. The device for measuring symmetry and perpendicularity of a gear shaft hole and a straight shaft hole of a differential case according to claim 1, characterized in that: The straight-axis hole positioning spindle (17) comprises a positioning spindle body (17-1), a positioning pin (17-2), a limiting sleeve (17-3), a double-stage bead bearing sleeve (17-4) and a limiting handle (17-5); The positioning spindle body (17-1) adopts a stepped shaft structure, and the limiting sleeve (17-3) is fastened to the position of the stepped shaft with a small diameter through the positioning pin (17-2). When one end of the double-section bead bearing sleeve (17-4) is pushed to contact the limiting sleeve (17-3), the front end balls of the double-section bead bearing sleeve (17-4) are all located at the position of the positioning spindle body (17-1) with a small diameter; when the rear end balls of the double-section bead bearing sleeve (17-4) are pushed to contact the straight-axis hole, the front end balls of the double-section bead bearing sleeve (17-4) are driven to the position of the positioning spindle body (17-1) with a large diameter, thereby achieving complete positioning of the straight-axis hole positioning spindle (17) on the straight-axis hole of the differential case.

6. The device for measuring symmetry and perpendicularity of a gear shaft hole and a straight shaft hole of a differential case according to claim 5, characterized in that: The front end balls of the double-section dense bead bearing sleeve (17-4) are all located at the position where the diameter of the positioning spindle body (17-1) is small. At this time, the clearance between the diameter of the positioning spindle body (17-1) and the straight-axis hole is greater than twice the diameter of the balls. After the straight-axis hole positioning spindle (17) is inserted into the straight-axis hole, it is in a clearance fit state. When the rear end balls of the double-section dense bead bearing sleeve (17-4) are pushed to contact the straight-axis hole, the position where the diameter of the positioning spindle body (17-1) is large is in contact with the straight-axis hole. The clearance is equal to or less than twice the diameter of the ball, and the ball performs pure rolling motion between the positioning spindle body (17-1) and the slotted shaft hole of the differential housing. The moving distance of the double-stage dense bead bearing sleeve (17-4) is half of the relative moving distance between the positioning spindle body (17-1) and the slotted shaft hole of the differential housing. After the movement, the ball at the front end of the double-stage dense bead bearing sleeve (17-4) also moves to a position with a larger diameter of the positioning spindle body (17-1), thereby completely positioning the slotted shaft hole of the differential housing.

7. The device for measuring symmetry and perpendicularity of a gear shaft hole and a straight shaft hole of a differential case according to claim 1, characterized in that: A measuring block (20) is installed at the bottom of the floating V-shaped member (9), a symmetry measuring micrometer (19) is installed on the measuring block (20) via a symmetry measuring micrometer base (18), a verticality measuring micrometer (15) is installed on a verticality measuring micrometer base (16), a measuring point of the verticality measuring micrometer (15) is located on the measuring block (20), and a distance between the measuring point and the center of the floating V-shaped member (9) is equal to the length of the slotted shaft hole of the differential housing; The symmetry measuring dial gauge base (18) and the verticality measuring dial gauge base (16) are both mounted on the base plate (2).

8. A method for measuring the symmetry and perpendicularity of a differential case gear shaft hole and a slotted shaft hole, characterized in that: The measuring method is implemented by the symmetry and perpendicularity measuring device for the differential case gear shaft hole and the slotted shaft hole as claimed in claims 1 to 7, and the specific steps of the measuring method are: Step 1: Position the gear shaft hole positioning spindle (14) and the gear shaft hole of the differential case; pass the straight shaft hole positioning spindle (17) through the circular hole of the gear shaft hole positioning spindle (14) and position it with the straight shaft hole of the differential case; Step 2: Place the positioning surfaces at both ends of the gear shaft hole positioning spindle (14) on the fixed V-shaped positioning piece (4), and place the slotted shaft hole positioning spindle on the floating V-shaped piece (9); Step 3: Set the symmetry dial gauge (19) and the verticality dial gauge (15) to zero, then remove the differential housing, rotate it 180° along the axial direction of the lower gear shaft hole and re-insert it into the V-shaped positioning piece. The change value of the symmetry dial gauge (19) is the symmetry, and the change value of the verticality dial gauge (15) corresponds to 2 times the verticality.

9. The method for measuring the symmetry and perpendicularity of the gear shaft hole and the slotted shaft hole of the differential case according to claim 8, characterized in that: After the apparent value of the symmetry micrometer (19) is set to zero, the center line of the gear shaft hole and the center line of the slotted shaft hole are set to be offset upward by Δ, and then the differential housing is rotated 180° along the gear shaft axis and placed on the V-shaped positioning piece again. At this time, the center line of the gear shaft hole and the center line of the slotted shaft hole should be offset downward by Δ. The apparent value change of the symmetry micrometer (19) is 2Δ, and 2Δ is the symmetry of the gear shaft hole and the slotted shaft hole of the differential housing. The change 2Δ is used to adjust the equipment coordinate parameters, that is, half of the change 2Δ, that is, Δ, is used as the adjustment coordinate. When the differential housing is inspected after processing, the symmetry of the gear shaft hole and the slotted shaft hole of the differential housing is 0.

10. The method for measuring the symmetry and perpendicularity of the gear shaft hole and the slotted shaft hole of the differential case according to claim 8, characterized in that: After the verticality dial gauge (15) is set to zero, the differential housing is rotated 180° along the gear shaft axis and then placed on the V-shaped positioning piece again to see the change in the verticality dial gauge (15). The change in the verticality is twice the verticality value of the gear shaft hole of the differential housing and the slotted shaft hole. Half of the change in the verticality is used as the coordinate parameter of the adjustment device. When the differential housing is inspected after processing, the verticality of the gear shaft hole of the differential housing and the slotted shaft hole is 0.

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