Eccentric tightening shaft

Abstract

The eccentric tightening shaft comprises a floating assembly, the floating assembly comprises a guide shaft fixedly installed on a base plate and an installation part installed on the guide shaft in a sliding mode, a tightening rod and an eccentric rod are arranged on the installation part at intervals, and the guide shaft, the tightening rod and the eccentric rod are parallel to one another; the upper end of the tightening rod is rotationally connected with the mounting part, and the lower end of the tightening rod corresponds to the tightening device and is located below one side of the base plate; the lower end of the eccentric rod is rotationally connected with the mounting part, and the upper end of the eccentric rod corresponds to a fastener to be tightened; the tightening rod is in transmission connection with the eccentric rod; when the tightening device is located below the base plate and acts on the lower end of the tightening rod, the tightening rod moves upwards to drive the mounting part and the eccentric rod to move upwards, and the upper end of the eccentric rod acts on a fastener to be tightened. Therefore, tightening operation of the fastener at the shielded tightening point is carried out on the original tightening assembly station, and damage to equipment, station waste and increase of manpower and material resource cost are avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of automobile assembly, in particular to an eccentric tightening shaft. Background Art

[0002] At present, in the production of automobiles, the tightening and assembling process of the vehicle body and components is essential. However, when tightening fasteners at the tightening and assembling station, some tightening points are often blocked by conveying equipment or other equipment for various reasons. At this time, it is very difficult for the anti-torsion arm or other tightening guns to directly fasten the components.

[0003] To solve the above problems, usually, the equipment is modified to dig holes to avoid the tightening points. Such a method damages the equipment, increases labor and manufacturing costs, and is not friendly to the introduction of new vehicle models in the later stage. It is very likely that the new vehicle models cannot be compatible in the later stage; or the positions where the tightening points are blocked are reserved for tightening at other unblocked stations, which will waste stations and increase labor and material costs. Summary of the Utility Model

[0004] The applicant of the present utility model aims at the above-mentioned disadvantages in the existing production technology and provides an eccentric tightening shaft, so as to perform the tightening operation of the fasteners at the blocked tightening points on the original tightening and assembling station, avoiding damage to the equipment, waste of stations, and increase of labor and material costs.

[0005] The technical solution adopted by the present utility model is as follows:

[0006] An eccentric tightening shaft includes a floating assembly. The floating assembly includes a guiding shaft fixedly installed on a substrate and an installation part slidably installed on the guiding shaft. A tightening rod and an eccentric rod are arranged at intervals on the installation part. The guiding shaft, the tightening rod, and the eccentric rod are parallel to each other;

[0007] The upper end of the tightening rod is rotatably connected to the installation part. The lower end of the tightening rod corresponds to a tightening device, and the lower end of the tightening rod is located below one side of the substrate;

[0008] The lower end of the eccentric rod is rotatably connected to the installation part, and the upper end of the eccentric rod corresponds to a fastener to be tightened;

[0009] The tightening rod and the eccentric rod are in transmission connection;

[0010] Wherein, when the tightening device is located below the substrate and acts on the lower end of the tightening rod, the tightening rod moves upward, thereby driving the installation part and the eccentric rod to move upward, and the upper end of the eccentric rod acts on the fastener to be tightened.

[0011] As a further improvement of the above technical solution:

[0012] The upper end of the eccentric rod is a sleeve.

[0013] A first synchronous pulley is arranged on the tightening rod, a second synchronous pulley is arranged on the eccentric rod, and the first synchronous pulley and the second synchronous pulley are connected by a synchronous belt for transmission.

[0014] The mounting portion is rotatably connected to the guide shaft and is used for rotating the mounting portion around the axis of the guide shaft.

[0015] It further includes a limiting member fixedly installed on the substrate, and the limiting member includes a limiting shaft parallel to the guide shaft;

[0016] A limiting hole is arranged on the mounting portion, the limiting shaft is located in the limiting hole, and the inner diameter of the limiting hole is larger than the diameter of the limiting shaft.

[0017] A conical boss is arranged below the limiting shaft, the conical boss is fixedly connected to the substrate, a conical hole is arranged below the limiting hole, and the conical hole is matched with the conical boss.

[0018] The floating assembly further includes a movable seat, the movable seat is of a tubular structure, two thrust ball bearings are fixedly installed on the movable seat along the axial direction, the two thrust ball bearings are connected through the mounting portion, and movable holes corresponding to the thrust ball bearings are arranged on the mounting portion. The inner diameter of the movable hole and the inner diameter of the seat ring of the thrust ball bearing are both larger than the outer diameter of the movable seat; the middle part of the movable seat is slidably connected to the guide shaft.

[0019] A fixing member is detachably installed at the upper end of the movable seat, a fixing structure is arranged at the lower end of the movable seat, and the two thrust ball bearings are fixed between the fixing member and the fixing structure.

[0020] The fixing member is threadedly connected to the movable seat.

[0021] A linear bearing slidably matched with the guide shaft is arranged in the movable seat.

[0022] The beneficial effects of the present utility model are as follows:

[0023] The structure of the present utility model is compact and reasonable, and the operation is convenient. By arranging a tightening rod and an eccentric rod which are connected by transmission on the substrate, the tightening device and the position to be tightened and assembled are connected in a dislocation manner, so as to realize the tightening operation of the blocked tightening point at the original tightening and assembling station without damaging the equipment and changing the operation station, and avoid increasing the labor and material costs.

[0024] The present utility model further has the following advantages:

[0025] (1) Rotate the installation part to be connected with the guide shaft, and set a limit part on the substrate. The limit part cooperates with the limit hole on the installation part. Control the swing amplitude of the installation part within a certain range by the diameter difference between the limit hole and the limit shaft to prevent the swing amplitude of the installation part around the guide shaft from being too large.

[0026] (2) Rotate the installation part and the movable seat through two thrust ball bearings. While enabling the installation part, the tightening rod, and the eccentric rod to rotate as a whole centered on the guide shaft, a small range of floating centered on the guide shaft is realized to absorb the small deviation between the fastener and the vehicle body during tightening and ensure that the bolt can be smoothly screwed into the vehicle body hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the present utility model.

[0028] Figure 2 is Figure 1 the top view of

[0029] Figure 3 is Figure 2 the axonometric sectional view of the A-A section in

[0030] Figure 4 is Figure 2 the sectional view of the B-B section in

[0031] Figure 5 It is a structural schematic diagram of the floating component of the present utility model.

[0032] Figure 6 is Figure 5 the sectional view of

[0033] Figure 7 It is a structural schematic diagram of the limit part of the present utility model.

[0034] Wherein: 1. Substrate;

[0035] 2. Floating component; 21. Guide shaft; 22. Installation part; 221. Limit hole; 222. Tapered hole; 223. Movable hole; 23. Thrust ball bearing; 24. Movable seat; 241. Linear bearing; 25. Fixed part; 26. Fixed structure; 27. Movable limit ring;

[0036] 3. Tightening rod; 31. First synchronous pulley; 32. External hexagonal tightening head;

[0037] 4. Eccentric rod; 41. Sleeve; 42. Second synchronous pulley;

[0038] 5. Limit part; 51. Limit shaft; 52. Tapered boss. SPECIFIC EMBODIMENTS

[0039] The following will describe the specific embodiments of the present invention in conjunction with the accompanying drawings.

[0040] Embodiment 1:

[0041] As Figures 1-3 shown, the eccentric tightening shaft of this embodiment includes a floating assembly 2. The floating assembly 2 includes a guide shaft 21 fixedly installed on the substrate 1 and a mounting portion 22 slidably installed on the guide shaft 21. Tightening rods 3 and eccentric rods 4 are arranged at intervals on the mounting portion 22. The guide shaft 21, the tightening rods 3, and the eccentric rods 4 are parallel to each other;

[0042] The upper end of the tightening rod 3 is rotatably connected to the mounting portion 22. The lower end of the tightening rod 3 corresponds to the tightening device, and the lower end of the tightening rod 3 is located below one side of the substrate 1;

[0043] The lower end of the eccentric rod 4 is rotatably connected to the mounting portion 22. The upper end of the eccentric rod 4 corresponds to the fastener to be tightened;

[0044] The tightening rod 3 and the eccentric rod 4 are in transmission connection;

[0045] Among them, when the tightening device is located below the substrate 1 and acts on the lower end of the tightening rod 3, the tightening rod 3 moves upward, thereby driving the mounting portion 22 and the eccentric rod 4 to move upward, and the upper end of the eccentric rod 4 acts on the fastener to be tightened.

[0046] Specifically, the substrate 1 can be a conveying device following the vehicle body or a certain part structure of the device, and bolts need to be assembled; the tightening device is an anti-torsion arm or other tightening guns arranged at the tightening assembly station. After the vehicle body is conveyed to the tightening assembly station, the output end of the tightening device moves upward, thereby jacking up the tightening rod 3 and being in transmission connection with the tightening rod 3. At the same time, the fastener arranged at the upper end of the eccentric rod 4 is aligned and positioned with the hole on the vehicle body. After the tightening device is started, the tightening rod 3 rotates and then drives the eccentric rod 4 to rotate through a synchronous belt. The rotation of the eccentric rod 4 drives the fastener to rotate for tightening operation.

[0047] Furthermore, the upper end of the eccentric rod 4 is a sleeve 41. The sleeve 41 is a standard internal hexagonal fastening sleeve, which is convenient for placing the fastener at the upper end of the eccentric rod 4. The lower end of the corresponding tightening rod 3 can be an external hexagonal tightening head 32, and the external hexagonal tightening head 32 acts on the output end of the tightening device. The lower end of the external hexagonal tightening head 32 is in an inverted conical shape, which cooperates with the output end of the tightening device to play a guiding role during the contact process.

[0048] Furthermore, a first synchronous pulley 31 is arranged on the tightening rod 3, and a second synchronous pulley 42 is arranged on the eccentric rod 4. The first synchronous pulley 31 and the second synchronous pulley 42 are in transmission connection through a synchronous belt.

[0049] Specifically, the tightening device is drivingly connected to the external hexagon tightening head 32, so that the torque is transmitted to the first synchronous pulley 31 through the flat key between the tightening rod 3 and the first synchronous pulley 31. The first synchronous pulley 31 transmits the torque to the second synchronous pulley 42 through the synchronous belt, and the second synchronous pulley 42 then transmits the torque to the eccentric rod 4 through a flat key. The eccentric rod 4 tightens the bolt through the sleeve 41, and fastens the part to the vehicle body, so as to achieve the purpose of tightening and assembling.

[0050] The tightening rod 3 and the eccentric rod 4 which are drivingly connected to each other are arranged on the substrate 1, and the tightening device and the position to be tightened and assembled are misaligned and connected, so as to realize the tightening operation of the blocked tightening point at the original tightening and assembling station without damaging the equipment and changing the operation station, and avoid increasing the labor and material costs.

[0051] Embodiment 2:

[0052] On the basis of Embodiment 1, a floating allowance of the eccentric rod 4 and the tightening rod 3 in the horizontal direction is set, which is convenient for the flexible docking of the tightening device and the eccentric rod 4, and absorbs the displacement during the rotation of the fastener when tightening the fastener. The improvement scheme is as follows.

[0053] As Figures 4-7 shown, the mounting portion 22 is rotatably connected to the guide shaft 21 for rotating the mounting portion 22 around the axis of the guide shaft 21.

[0054] It further includes a limiting member 5 fixedly mounted on the substrate 1. The limiting member 5 includes a limiting shaft 51 parallel to the guide shaft 21;

[0055] A limiting hole 221 is provided on the mounting portion 22. The limiting shaft 51 is located in the limiting hole 221, and the inner diameter of the limiting hole 221 is larger than the diameter of the limiting shaft 51.

[0056] A conical boss 52 is provided below the limiting shaft 51. The conical boss 52 is fixedly connected to the substrate 1. A conical hole 222 is provided below the limiting hole 221, and the conical hole 222 matches the conical boss 52.

[0057] The mounting portion 22 is rotatably connected to the guide shaft 21, and the limiting member 5 is arranged on the substrate 1. The limiting member 5 cooperates with the limiting hole 221 on the mounting portion 22, and the swing amplitude of the mounting portion 22 is controlled within a certain range by the diameter difference between the limiting hole 221 and the limiting shaft 51, so as to avoid the swing amplitude of the mounting portion 22 around the guide shaft 21 from being too large.

[0058] When the tightening device acts on the external hexagonal tightening head 32, the installation part 22, the tightening rod 3, and the eccentric rod 4 are lifted as a whole, the conical boss 52 and the conical hole 222 are disengaged, and the installation part 22, the tightening rod 3, and the eccentric rod 4 can rotate around the guide shaft 21 as the center and rotate within the clearance range between the limit hole 221 and the limit shaft 51, so as to realize the positioning when the fastener, i.e., the bolt, in the sleeve 41 is aligned with the vehicle body.

[0059] After the tightening device releases the action on the tightening rod 3, the installation part 22, the tightening rod 3, and the eccentric rod 4 fall as a whole and reset under the cooperation of the conical boss 52 and the conical hole 222.

[0060] As Figures 3-6 shown, the floating assembly 2 further includes a movable seat 24. The movable seat 24 is of a tubular structure. Two thrust ball bearings 23 are fixedly installed on the movable seat 24 along the axial direction. The two thrust ball bearings 23 are connected through the installation part 22. The installation part 22 is provided with movable holes 223 corresponding to the thrust ball bearings 23. The inner diameter of the movable holes 223 and the inner diameter of the seat rings of the thrust ball bearings 23 are both larger than the outer diameter of the movable seat 24. The middle part of the movable seat 24 is slidably connected with the guide shaft 21.

[0061] A fixing part 25 is detachably installed at the upper end of the movable seat 24, and a fixing structure 26 is arranged at the lower end of the movable seat 24. The two thrust ball bearings 23 are fixed between the fixing part 25 and the fixing structure 26.

[0062] The fixing part 25 is threadedly connected with the movable seat 24. Specifically, the fixing part 25 is a locking round nut.

[0063] A linear bearing 241 that is slidably matched with the guide shaft 21 is arranged in the movable seat 24.

[0064] Specifically, the two thrust ball bearings 23 are fixedly installed on the movable seat 24, that is, the axial position of the thrust ball bearings 23 relative to the movable seat 24 remains unchanged. The fixing structure 26 is a flanging structure at the lower end of the movable seat 24, and the shaft ring of the lower thrust ball bearing 23 is fixedly connected with the fixing structure 26. The two thrust ball bearings 23 are mirror-symmetrical. The seat rings of the two thrust ball bearings 23 are respectively located in two circular grooves on the upper and lower surfaces of the installation part 22 and are tightly fitted with the grooves. The shaft ring of the upper thrust ball bearing 23 is radially limited by connecting with the outer periphery of the movable seat 24 through a movable limit ring 27. At the same time, the fixing part 25 is threadedly connected with the movable seat 24 to limit the movable limit ring 27, the thrust ball bearings 23, the installation part 22, and the other thrust ball bearing 23 between the fixing part 25 and the fixing structure 26. The distance between the movable holes 223 and the movable seat 24 provides a movable space for the thrust ball bearings 23.

[0065] The mating structure of the linear bearing 241 and the guide shaft 21 can ensure the vertical accuracy during the vertical upward movement when tightening and the vertical downward movement after tightening; the mounting part 22 and the movable seat 24 are rotationally connected by two thrust ball bearings, so that while the mounting part 22, the tightening rod 3 and the eccentric rod 4 rotate as a whole around the guide shaft 21, they can float within a small range around the guide shaft 21, absorbing the small deviation between the fastener and the vehicle body during tightening and ensuring that the bolt can be smoothly screwed into the vehicle body hole.

[0066] The eccentric tightening shaft of this embodiment has a simple structure and high reliability, and has low requirements for the stroke and space of the tightening machine. By using the eccentric tightening shaft for eccentric tightening, it can effectively avoid and block interference points, fasten the parts and the vehicle body, without damaging the equipment, without involving adding workstations, saving costs, and can effectively solve the problem that the tightening points between the vehicle body and the parts are blocked by the equipment and cannot be smoothly fastened.

[0067] The above description is an explanation of the present invention, not a limitation of the invention. For the scope defined by the present invention, refer to the claims. Within the protection scope of the present invention, any form of modification can be made.

Claims

1. An eccentric tightening shaft, characterized in that: The floating assembly (2) comprises a guide shaft (21) fixedly mounted on a base plate (1) and a mounting portion (22) slidably mounted on the guide shaft (21); a tightening rod (3) and an eccentric rod (4) are arranged on the mounting portion (22) at intervals; and the guide shaft (21), the tightening rod (3) and the eccentric rod (4) are parallel to each other. The upper end of the tightening rod (3) is rotatably connected to the mounting portion (22), the lower end of the tightening rod (3) corresponds to the tightening device, and the lower end of the tightening rod (3) is located below one side of the base plate (1); The lower end of the eccentric rod (4) is rotatably connected to the mounting portion (22), and the upper end of the eccentric rod (4) corresponds to a fastener to be tightened; The tightening rod (3) is transmission-connected to the eccentric rod (4); When the tightening device is located below the base plate (1) and acts on the lower end of the tightening rod (3), the tightening rod (3) moves upwards, thereby driving the mounting portion (22) and the eccentric rod (4) to move upwards, and the upper end of the eccentric rod (4) acts on the fastener to be tightened.

2. An eccentric tightening shaft according to claim 1, characterized in that: The upper end of the eccentric rod (4) is a sleeve (41).

3. An eccentric tightening shaft according to claim 1, characterized in that: The tightening rod (3) is provided with a first synchronous wheel (31), and the eccentric rod (4) is provided with a second synchronous wheel (42). The first synchronous wheel (31) and the second synchronous wheel (42) are connected by a synchronous belt transmission.

4. An eccentric tightening shaft according to claim 1, characterized in that: The mounting portion (22) is rotatably connected to the guide shaft (21) so as to enable the mounting portion (22) to rotate around the axis of the guide shaft (21).

5. An eccentric tightening shaft according to claim 4, characterized in that: It also includes a limiting member (5) fixedly mounted on the base plate (1), wherein the limiting member (5) includes a limiting axis (51) parallel to the guide axis (21); A limiting hole (221) is provided on the mounting portion (22), the limiting shaft (51) is located in the limiting hole (221), and the inner diameter of the limiting hole (221) is greater than the diameter of the limiting shaft (51).

6. An eccentric tightening shaft according to claim 5, characterized in that: A conical boss (52) is provided below the limiting shaft (51), and the conical boss (52) is fixedly connected to the base plate (1); a conical hole (222) is provided below the limiting hole (221), and the conical hole (222) matches the conical boss (52).

7. An eccentric tightening shaft according to claim 4, characterized in that: The floating assembly (2) further comprises a movable seat (24), the movable seat (24) being a tubular structure, the movable seat (24) being fixedly mounted with two thrust ball bearings (23) along the axial direction, the two thrust ball bearings (23) being connected via the mounting portion (22), the mounting portion (22) being provided with a movable hole (223) corresponding to the thrust ball bearing (23), the inner diameter of the movable hole (223) and the inner diameter of the seat ring of the thrust ball bearing (23) being both larger than the outer diameter of the movable seat (24); the middle portion of the movable seat (24) being slidably connected to the guide shaft (21).

8. An eccentric tightening shaft according to claim 7, characterized in that: A fixing piece (25) is detachably mounted on the upper end of the movable seat (24), a fixing structure (26) is provided on the lower end of the movable seat (24), and two thrust ball bearings (23) are fixed between the fixing piece (25) and the fixing structure (26).

9. An eccentric tightening shaft according to claim 8, characterized in that: The fixing member (25) is threadedly connected to the movable seat (24).

10. An eccentric tightening shaft according to claim 7, characterized in that: A linear bearing (241) that is slidably matched with the guide shaft (21) is arranged in the movable seat (24).

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