An automatic centering flexible fixture

Abstract

The present invention discloses an automatic self-aligning flexible clamp, comprising a clamp bottom plate, a clamp bottom frame and a clamping device installed on the clamp bottom frame, wherein the clamp bottom frame is flexibly connected to the clamp bottom plate through an elastic device and a movable device, and when the clamp bottom frame is subjected to an external force, it is displaced through the movable device, and when the external force is eliminated, the clamp bottom frame is reset through the elastic device. The clamp of the present invention realizes the dynamic concentricity of the threaded hole on the product to be threaded with the screw, and can quickly and easily realize the real-time concentricity of the product threaded hole and the screw, solves the problem of the screw not being locked in place and the screw thread surface being damaged due to the eccentricity problem, reduces the labor cost, and improves the production efficiency and product quality.

Description

Technical Field

[0001] The invention relates to the technical field of clamping tools, in particular to an automatic centering flexible clamp. Background Art

[0002] With the change of production technology, more and more automated equipment is put into production line operation to replace manual simple and repetitive assembly line operations, thereby reducing labor costs and improving productivity and corporate competitiveness. At present, automatic screw threading machines have been widely used, but in the process of use, there are often quality problems such as the screw not being threaded in place and the screw thread surface being damaged (silver plating layer damaged) after the screw is threaded. Manual processing is required, which increases the workload, reduces production efficiency, affects production capacity, and also increases production costs. Summary of the invention

[0003] The main technical problem solved by the present invention is to avoid the problem of the screw being out of center with the threaded hole on the product, thereby solving the problem of the screw not being able to be inserted into place and the screw being damaged, and eliminating the product defects that may be caused by the above-mentioned screw insertion process.

[0004] In order to solve the above technical problems, a technical solution adopted by the present invention is: to provide an automatic self-aligning flexible clamp, including a clamp base plate, a clamp bottom frame and a clamping device installed on the clamp bottom frame, the clamp bottom frame and the clamp base plate are flexibly connected through an elastic device and a movable device, when the clamp bottom frame is subjected to external force, it can be displaced through the movable device, and when the external force is eliminated, the clamp bottom frame is reset through the elastic device.

[0005] Wherein, the elastic device comprises an elastic member and a fixing mechanism arranged on the clamp bottom plate, the fixing mechanism is fixed to the clamp bottom plate, one end of the elastic member is connected to the fixing mechanism, and the other end is fixed to the clamp bottom frame.

[0006] Wherein, at least two of the elastic devices are symmetrically distributed around the center of the plane where the clamp bottom frame is located.

[0007] Wherein, the elastic member is at least one of a tension spring, an elastic rope, a rubber ring, and a hydraulic rod.

[0008] Among them, the movable device is a steel ball roller, and a groove is provided at a corresponding position on the clamp bottom plate. The stud part of the steel ball roller is stuck in the clamp bottom frame, and the steel ball part is embedded in the groove. When the clamp bottom frame is subjected to external force, the steel ball roller can roll in the groove.

[0009] Wherein, the groove is an arc-shaped groove, and the number of the steel ball rollers and the grooves is multiple groups.

[0010] Wherein, the movable device is an XY two-way guide rail structure, the XY two-way guide rail structure is fixed on the fixture bottom plate, and the fixture bottom frame is fixed on the XY two-way guide rail structure.

[0011] Wherein, the clamping device comprises at least two guide rails arranged on the bottom frame of the clamp and positioning blocks arranged on the guide rails, and the positioning blocks on at least two of the guide rails can move in two directions perpendicular to each other.

[0012] Wherein, the clamping device comprises two guide rails arranged in parallel on the bottom frame of the clamp, and also comprises a plurality of positioning plates, the bottom ends of the positioning plates are fixed on the bottom frame of the clamp or mounted on the sliders of the guide rails;

[0013] A sliding groove is provided on the positioning plate, and each positioning plate and the guide rail are provided with at least one positioning block. The positioning blocks are provided with a slot for fixing the screw product to be inserted, and each positioning block can slide along the corresponding guide rail or the sliding groove and be fixed by screws.

[0014] Wherein, a floating end positioning plate is further provided between the two positioning plates, the floating end positioning plate is fixed on the bottom frame of the fixture or can slide along the sliding groove, the floating end positioning plate is provided with at least one floating end positioning block, and the floating end positioning block is provided with a card slot for fixing the screw product to be threaded;

[0015] The floating end positioning block can slide along the floating end sliding groove provided on the floating end positioning plate and be fixed by screws.

[0016] Through the above technical solution, the threaded hole on the screw product to be inserted is dynamically concentric with the screw, which can quickly and easily achieve real-time concentricity between the product threaded hole and the screw, solving the problems of inability to lock in place and damage to the screw thread surface caused by eccentricity of the screw, reducing labor costs and improving production efficiency and product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a structural schematic diagram of an embodiment of an automatic centering flexible clamp of the present invention;

[0019] Figure 2 It is a top view of an embodiment of an automatic centering flexible clamp of the present invention. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] In view of the above problems, the inventors of the present invention have found that the existing automatic screw threading machine uses a fixed fixture, which has the following disadvantages:

[0022] After this type of fixing fixture is installed, the concentricity of the screw and the threaded hole on the product depends on the machining and assembly accuracy of the fixture. If the deviation is large, the screw will not be able to pass through the cover plate. Increasing the torque for threading the screw can improve this problem, but it will increase the damage to the screw thread surface and destroy the silver plating on the screw surface, resulting in defects. In the industry, CCD detection can be used to correct the deviation of the fixing fixture, but because the screw and the bit cannot be completely concentric, the center of the screw is constantly changing during the actual rotation of the screw, so installing a CCD correction system will also cause the screw and the threaded hole on the cover plate to be non-concentric. Therefore, the present invention provides the following solution to solve the problem of the screw not being able to pass through and the screw being damaged, and eliminate the technical problem of product defects that may be caused by the above-mentioned screw threading process.

[0023] See also Figure 1 , Figure 1 It is a schematic diagram of an automatic centering flexible clamp of the present invention, including a clamp base plate 1, a clamp base frame 3 and a clamping device installed on the clamp base frame 3. The clamp base frame 3 is flexibly connected to the clamp base plate 1 through an elastic device and a movable device 2. When the clamp base frame 3 is subjected to external force, it can be offset through the movable device 2. When the external force is eliminated, the clamp base frame 3 is reset through the elastic device. The clamp base frame 3 is provided with a guide rail 11 and a positioning device installed on the guide rail 11. The screw product 8 to be threaded is fixed on the clamp base frame 3 through the positioning device. The clamp base plate 1 is fixed on the automatic screw threading machine, and the screw product 8 to be threaded is fixed on the clamp base frame 3. The positional relationship between the threaded hole on the product and the screw is adjusted so that the screw passes through the threaded hole on the screw product to be threaded on the clamp, and then the nut is locked. Since the center of the screw and the threaded hole may deviate, the present embodiment sets a dynamic automatic centering flexible clamp so that the two are always concentric to avoid product defects caused by non-concentricity. This embodiment realizes flexible adjustment of the center by providing an elastic device and a movable device 2. Even if the bottom frame 3 of the clamp is moved by external force, it will be reset by the elastic device to reach a dynamic equilibrium state, so that the screw and the threaded hole are always concentric. The specific structure will be described in detail below.

[0024] The elastic device in this embodiment includes an elastic member 13 and a fixing mechanism 12 arranged on the clamp bottom plate 1, the fixing mechanism 12 is fixed on the clamp bottom plate 1, one end of the elastic member 13 is connected to the fixing mechanism 12, and the other end is fixed on the clamp bottom frame 3. The elastic member 13 provides a rebound force for the flexible clamp, so that the clamp bottom frame 3 is reset under the action of the rebound force after moving. The elastic device 13 of the present invention can have multiple implementation methods. In order to achieve a dynamic balance of force, the number of elastic devices is set to an even number, and at least two elastic devices are symmetrically distributed around the center of the plane where the clamp bottom frame is located, so that no matter from which direction the clamp bottom frame 3 is subjected to force, it can return to its original position. In this embodiment, four elastic devices are set as an example, all of which are set at the four corners of the clamp bottom plate 1 and arranged symmetrically. When the clamp bottom plate 1 and the clamp bottom frame 3 are in a normal corresponding position, the elastic member 13 is in a relaxed state. Since the elastic member 13 is symmetrically fixed at the four corners of the clamp bottom plate 1, the clamp bottom frame 3 is in a balanced state, and the force in any direction can make it move. When the clamp bottom frame 3 is moved by external force, two elastic members 13 compress the other two elastic members 13 and stretch them. When the external force is eliminated, due to the elastic force of the four elastic members 13, the clamp bottom frame 3 automatically returns to the initial position and returns to the balanced state, thereby achieving the function of automatically adjusting the center. The elastic member 13 can be at least one of a tension spring, an elastic rope, a rubber ring, and a hydraulic rod. The fixing mechanism 12 can be selected as a fixing block, the bottom of which is fixed on the clamp bottom frame 3, providing a fixed end for the elastic member 13.

[0025] The movable device 2 in this embodiment is a steel ball roller, and an arc groove is provided at the corresponding position on the fixture bottom plate 1. The number of steel ball rollers and grooves is multiple groups. In this embodiment, four groups are taken as an example, which are distributed at the four corners of the fixture, corresponding to the number and position of the elastic members. One end of the steel ball roller is a stud with an external thread on the outside, and the other end is a rotating head. A steel ball is provided in the center of the rotating head. Part of the steel ball is exposed from the rotating head and can rotate on any contact surface. The stud part of the steel ball roller is clamped in the fixture bottom frame 3 through interference fit, and the rotating head part is embedded in the arc groove. Since the friction coefficient of the steel ball roller is very small, when the fixture bottom frame 3 is subjected to external force, the steel ball can roll smoothly in any direction in the groove.

[0026] The movable device 2 in another embodiment is an XY two-way guide rail structure, the XY two-way guide rail structure is fixed on the fixture bottom plate 1, and the fixture bottom frame 3 is fixed on the XY two-way guide rail structure. The use of the XY two-way guide rail structure for sliding can also achieve the effect of automatic centering. Of course, such a setting does not require the arc groove to be provided on the fixture bottom plate 1. The XY two-way guide rail is directly installed and fixed on the fixture bottom plate 1, and the fixture bottom frame 3 is fixed on the XY two-way guide rail. One end of the elastic device is connected to the fixture bottom plate, and the other end is connected to the guide rail. When the clamp bottom frame 3 is subjected to external force, it can slide toward the X-axis or Y-axis direction through the XY two-way guide rail structure. When the external force is eliminated, the clamp bottom frame 3 is reset through the elastic device. The elastic member can continue to use the tension spring, elastic rope, rubber ring or hydraulic rod used for the above-mentioned steel ball roller. In this way, the purpose of flexible centering can be achieved. However, due to the limitation of the XY two-way guide rail structure, the force direction is limited to the X-axis or Y-axis. When subjected to forces in other directions, the sliding effect of the clamp bottom frame 3 is not good, and the threaded hole on the product to be inserted with the stud cannot be well concentric. The structure of this embodiment can meet the use requirements of specific products and processes.

[0027] The clamping device in this embodiment includes at least two guide rails 11 arranged on the bottom frame 3 of the clamp and positioning blocks arranged on the guide rails 11. The positioning blocks on at least two guide rails 11 can move in two directions perpendicular to each other. The clamping device needs to fix at least two sides of the screw product 8 to be threaded in order to obtain a relatively stable clamping effect. Of course, the stability will be higher if three or four guide rails are set. In this embodiment, two adjacent and perpendicular guide rails 11 are set as an example. The guide rails 11 are respectively arranged on the adjacent two sides of the bottom frame 3 of the clamp. The guide rails 11 are linear guide rails. A single or multiple positioning blocks are arranged on the guide rails 11 for sliding of the positioning blocks so as to clamp different positions of the screw product 8 to be threaded. This embodiment uses the positioning blocks on the guide rails 11 for clamping, at least clamping the two sides of the screw product 8 to be threaded. Of course, four guide rails 11 can also be set for clamping four sides, but the guide rails 11 are fixed on the bottom frame 3 of the clamp, so that the clamping range of the clamping device cannot be adjusted, which is suitable for clamping a specific product with fixed external dimensions.

[0028] See also Figure 2A top view shows that the clamping device in another embodiment includes two guide rails 11 arranged in parallel on the clamp bottom frame 3, and also includes a plurality of positioning plates, the bottom ends of the positioning plates are fixed on the clamp bottom frame 3 or installed on the sliders 16 of the guide rails 11; sliding grooves are arranged on the positioning plates, and at least one positioning block is arranged on each positioning plate and the guide rail 11, and a card slot is arranged on the positioning blocks for fixing the screw product 8 to be threaded, and each positioning block can slide along the corresponding guide rail 11 or sliding groove, and is fixed by screws. In this embodiment, two positioning plates are set as an example, and the two positioning plates are respectively a fixed end positioning plate 4 fixed on the clamp bottom frame 3 and a movable end positioning plate 10 fixed on the sliders 16 of the two parallel guide rails 11, both of which are perpendicular to the two guide rails 11, and the movable end positioning plate 10 can slide along the guide rails 11, and the fixed end positioning plate 4 is fixed to the end of the clamp bottom frame 3, and both are provided with sliding grooves. At least one guide rail end positioning block 6, fixed end positioning block 5 and movable end positioning block 15 are respectively provided on the two guide rails 11, the fixed end positioning plate 4 and the movable end positioning plate 10, which can move along the corresponding guide rail 11 direction or the sliding groove direction and are fixed by screws. A handle 7 is also provided on the guide rail 11 for adjusting the guide rail end positioning block 6. The clamping grooves on the guide rail end positioning block 6, the fixed end positioning block 5 and the movable end positioning block 15 clamp one side of the screw product 8 to be inserted, and fix the screw product 8 to be inserted.

[0029] In the above-mentioned embodiment, the guide rail end positioning blocks 6, the movable end positioning plate 10 and the fixed end positioning plate 4 of the two guide rails 11 are respectively arranged in the four directions of the screw product 8 to be threaded, and only the movable end positioning plate 10 is movable, and the two guide rails 11 and the fixed end positioning plate 4 are not movable. The clamping range of the clamping device is adjusted by the displacement of the movable end positioning plate 10, and then the different positions of the screw product 8 to be threaded are selected by sliding each positioning block, and the four directions of the screw product 8 to be threaded are fixed and limited, so that the screw product 8 to be threaded cannot move. This structure can only be adjusted in the displacement direction parallel to the guide rail 11, that is, the movable end positioning plate 10, and cannot be adjusted in the vertical direction of the guide rail 11. The clamping range of the clamping device can only be adjusted in one direction, which also has certain defects.

[0030] In order to avoid the above problems, in this embodiment, a floating end positioning plate 14 is further provided between the fixed end positioning plate 4 and the movable end positioning plate 10. The floating end positioning plate 14 is fixed on the clamp bottom frame 3 or can slide along the sliding groove. The floating end positioning plate 14 is provided with at least one floating end positioning block 9. The floating end positioning block 9 is provided with a slot for fixing the screw product 8 to be threaded. The floating end positioning block 9 can slide along the floating end sliding groove provided on the floating end positioning plate 14 and is fixed by screws. In order to enable the clamping device to adjust the clamping range of the screw product 8 to be threaded in both the length and width directions, a floating end positioning plate 14 is provided in the middle of the clamp bottom frame 3, parallel to the fixed end positioning plate 4 and the movable end positioning plate 10. The floating end positioning plate 14 can be fixedly provided or provided at both ends on the movable end positioning plate 10 and the fixed end positioning plate 4, slide along the sliding groove in a direction perpendicular to the movement direction of the movable end positioning plate 10, and adjust the clamping range of the clamping device together with the movable end positioning plate 10. The floating end positioning block 9 can also slide in the floating end sliding groove on the floating end positioning plate 14. At this time, the guide rail end positioning block 6, the fixed end positioning block 5, the movable end positioning block 15 and the floating end positioning block 9 are respectively located on four different faces of the screw product 8 to be threaded, and the four positioning blocks are used to clamp and fix in different directions. Of course, it can also be fixed on the bottom frame 3 of the clamp, and the two ends and the top surface are respectively fixed to the side wall of the fixed end positioning plate 4 and the bottom of the movable end positioning plate 10. Since it is fixed and cannot slide, it can only clamp products of specific sizes.

[0031] The number of the guide rail end positioning block 6, the fixed end positioning block 5, the movable end positioning block 15 and the floating end positioning block 9 in this embodiment is at least one. When there are multiple positioning blocks, each positioning block can be dispersed at equal distances during use, and the force can be evenly applied to clamp the product more stably.

[0032] By using the automatic centering flexible clamp of the present invention, an elastic device and a rolling device are provided to connect the clamp bottom plate and the clamp bottom frame, so that the threaded hole on the product and the stud can automatically adjust their centers, and the threaded hole on the product to be threaded with the screw and the screw can be dynamically concentric, thereby solving the problems of the screw not being able to be locked in place and the screw thread surface being damaged due to the eccentricity problem, reducing labor costs and improving production efficiency and product quality.

[0033] The above description is only an implementation mode of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. An automatic centering flexible clamp, characterized in that: The clamp comprises a clamp bottom plate, a clamp bottom frame and a clamping device installed on the clamp bottom frame, wherein the clamp bottom frame is flexibly connected to the clamp bottom plate through an elastic device and a movable device, at least two of the elastic devices are symmetrically distributed about the center of the plane where the clamp bottom frame is located, and when the clamp bottom frame is subjected to an external force, the clamp bottom frame is deflected through the movable device, and when the external force is eliminated, the clamp bottom frame is reset through the elastic device; The clamping device comprises at least two guide rails arranged on the bottom frame of the clamp and positioning blocks arranged on the guide rails, and the positioning blocks on at least two of the guide rails can move in two directions perpendicular to each other, or, the clamping device comprises two guide rails arranged in parallel on the bottom frame of the clamp, and also comprises a plurality of positioning plates, and the bottom ends of the positioning plates are fixed on the bottom frame of the clamp or mounted on the sliders of the guide rails; The positioning plate is provided with a sliding groove, each positioning plate and the guide rail is provided with at least one positioning block, each positioning block is provided with a slot for fixing the screw product to be inserted, each positioning block can slide along the corresponding guide rail or the sliding groove and be fixed by screws; A floating end positioning plate is also provided between the two positioning plates, the floating end positioning plate is fixed on the bottom frame of the fixture or can slide along the sliding groove, the floating end positioning plate is provided with at least one floating end positioning block, and the floating end positioning block is provided with a slot for fixing the screw product to be threaded; The floating end positioning block can slide along the floating end sliding groove provided on the floating end positioning plate and be fixed by screws.

2. The automatic centering flexible clamp according to claim 1, characterized in that: The elastic device comprises an elastic member and a fixing mechanism arranged on the clamp bottom plate, the fixing mechanism is fixed on the clamp bottom plate, one end of the elastic member is connected to the fixing mechanism, and the other end is fixed on the clamp bottom frame.

3. The automatic centering flexible clamp according to claim 2, characterized in that: The elastic member is at least one of a tension spring, an elastic rope, a rubber ring, and a hydraulic rod.

4. The automatic centering flexible clamp according to any one of claims 1 to 3, characterized in that: The movable device is a steel ball roller, and a groove is provided at a corresponding position on the clamp bottom plate. The stud part of the steel ball roller is stuck in the clamp bottom frame, and the steel ball part is embedded in the groove. When the clamp bottom frame is subjected to external force, the steel ball roller can roll in the groove.

5. The automatic centering flexible clamp according to claim 4, characterized in that: The groove is an arc-shaped groove, and the number of the steel ball rollers and the grooves is multiple.

6. The automatic centering flexible clamp according to any one of claims 1 to 3, characterized in that: The movable device is an XY two-way guide rail structure, the XY two-way guide rail structure is fixed on the fixture bottom plate, and the fixture bottom frame is fixed on the XY two-way guide rail structure.

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