CN114799982A

CN114799982A - Double-conical-surface boosting clamping mechanism

Info

Publication number: CN114799982A
Application number: CN202210734834.XA
Authority: CN
Inventors: 罗庆丰; 王超; 郭祥福; 李效民; 朱祝生; 杨甫; 张又予; 常启彪; 李朔斌; 樊兴荣; 张建兵
Original assignee: Yunnan Machinery Research And Design Institute Co ltd
Current assignee: Yunnan Machinery Research And Design Institute Co ltd
Priority date: 2022-06-27
Filing date: 2022-06-27
Publication date: 2022-07-29

Abstract

The invention discloses a double-conical-surface boosting clamping mechanism, wherein a fastening head is arranged on one side of a pull rod, the other side of the pull rod is fixed in a pressure-bearing disc, a front plug is arranged at the front end of a cylinder body, the pressure-bearing disc is coaxially arranged in the cylinder body and forms a hollow inner cavity with the front plug, an elastic body is arranged in the hollow inner cavity, the front end of the elastic body is abutted against the rear end of the front plug, a first conical block is arranged outside the pressure-bearing disc in a sliding mode, the front end of the first conical block is abutted against the rear end of the elastic body, the outer side of the rear end of the first conical block forms a first conical surface, a second conical block is arranged in a cylinder body step through hole on the outer side of the first conical block, the front end of the first conical block is abutted against a step end surface of the step through hole, the inner side of the rear end of the rear plug forms a second conical surface, a ring is arranged at one end of the pressure-bearing disc, a ball body is arranged in a wedge-shaped space among the first conical surface, a second conical surface and the front end surface of the ring, and a piston is arranged in a sliding mode and fixed at the rear end of the cylinder body. The invention has the characteristics of compact structure, larger reinforcement amplification factor, small friction loss and clamping and self-locking.

Description

Double-conical-surface boosting clamping mechanism

Technical Field

The invention relates to the technical field of machine tool tables, in particular to a double-conical-surface boosting clamping mechanism which is compact in structure, large in boosting amplification coefficient, small in friction loss and capable of clamping and self-locking.

Background

In general, a tool holder of a machine tool such as a cutting and grinding tool is fixed to a spindle by a clamp mechanism. Conventionally, a conical surface matched with a tool holder is generally arranged at one end of a main shaft, a blind rivet is connected with the tool holder, a tensioning mechanism is connected with the other end of the main shaft, a pull pin in the tensioning mechanism is connected with the blind rivet through a clamping flap, and a spring is sleeved outside the clamping flap; when the tool is detached, the external force is closed, and the clamping clacks at one end of the blind rivet are opened under the rebound of the spring to release the tool handle; or conversely, when the tool is in operation, the disk spring provides tension to enable the handle to be clamped and fixed in the main shaft, and when the tool is removed, the pull pin is moved towards the rivet direction through external force, so that the clamping petals at one end of the pull pin are contracted, the clamping petals at one end of the pull pin are expanded, and the end head of the pull pin abuts against the end head of the pull pin to enable the handle to be separated. If the clamping mechanism is clamped by the clamping force, the self-locking cannot be realized due to the fact that external force is needed to maintain, the reliability is low, the energy consumption is high, the generated pulling force is small, and the tool holder is not firmly fixed; and with the mode that belleville spring provided the clamp force, because single belleville spring can't provide enough big power, if only rely on increasing belleville spring quantity to realize grabbing sword power, then the volume great can lead to clamping mechanism's oversize, and also increases the required loose sword power of handle of a knife unclamping.

In the prior art, in order to solve the problems of the traditional clamping mechanism, mechanical clamping mechanisms such as a hydraulic device and a mechanical screw rod locking device are mostly adopted for clamping, but if fluid devices such as hydraulic devices need to maintain a high-pressure clamping force for a long time, the volume of the device is too large, and leakage occurs due to overlarge hydraulic pressure, so that the clamping reliability is reduced; when the mechanical screw rod locking device clamps a workpiece, a large rotating torque is applied, and the requirement for clamping the workpiece is difficult to meet due to high labor intensity. Therefore, in the prior art, a proper mechanical force increasing mechanism is combined on the basis of fluid transmission technologies such as hydraulic pressure, air pressure and the like, so that the working pressure of a fluid system can be effectively reduced, the service life of the fluid system is prolonged, and the clamping reliability can be improved; however, when the common lever force-increasing mechanism, hinge rod force-increasing mechanism, wedge force-increasing mechanism and the like are used for a hydraulic clamp, the clamp structure is not compact, the friction loss is large, and the force amplification coefficient is effective. For example, the existing steel ball-steel ball type primary force increasing mechanism has a small force amplification coefficient, and the direction of output force is vertical to the direction of input force; however, as part of the steel ball-double-inclined-plane type secondary force increasing mechanism, although the amplification factor is large, the friction loss of force in the transmission process is too large due to the surface friction between the double inclined-plane type and the double inclined-plane type. And the clamping force of the mechanism can be maintained under the external force, and certain potential safety hazards exist for high-reliability clamping. Therefore, in the prior art, a self-locking oil path and a mechanical self-locking mechanism are additionally arranged on the clamping mechanism, and the oil path self-locking is realized by additionally arranging a hydraulic valve for pressure maintaining, so that the hydraulic oil of the oil cylinder does not return to the oil tank, and the oil pressure in the oil cylinder is stable; however, the hydraulic lock adopted by the oil circuit self-locking has larger overall dimension and the valve core cannot realize zero leakage, and the piston rod still moves to influence the locking effect when the oil cylinder is subjected to larger load or along with the time. The mechanical self-locking is to additionally arrange a nut on a piston rod of the oil cylinder, and after the piston rod of the oil cylinder extends out of a required position, the nut on the piston rod of the oil cylinder is rotated to the bottom to be contacted with the cylinder body, so that the piston rod is fixed to the required position; however, the mechanical self-locking requires manual rotation of the nut, which is difficult to smoothly perform under certain specific working conditions or is easy to cause personal safety accidents and equipment damage. Therefore, a follow-up self-locking mechanism is vertically arranged on one side of the clamping rod, and the clamping rod and the ratchet on the locking rod are mutually engaged to realize locking by manual or electric control; although the locking is reliable and can be maintained without external force after being locked, the structure is more complex and the space occupation is larger due to the vertically-compared structure.

Disclosure of Invention

The invention aims to provide a double-conical-surface boosting clamping mechanism which is compact in structure, large in boosting amplification coefficient, small in friction loss and capable of clamping and self-locking.

The invention is realized by the following steps: the elastic body is arranged in the hollow inner cavity, the front end of the elastic body is abutted to the rear end of the front plug, the first conical block is arranged outside the pressure bearing disc in a sliding mode, the front end of the first conical block is abutted to the rear end of the elastic body, a first conical surface is formed on the outer side of the rear end of the first conical block, the second conical block is arranged in the inner cavity of the step through hole of the cylinder body on the outer side of the first conical block, the front end of the second conical block is abutted to the step end face of the step through hole, and a second conical surface is formed on the inner side of the rear end of the second conical block, the bearing plate is further provided with a ring platform at one end far away from the fastening head, the ball body is arranged in a wedge-shaped space formed among the first conical surface, the second conical surface and the front end face of the ring platform, the piston is coaxially arranged in the cylinder body in a sliding mode, and the rear plug is fixedly arranged at the rear end of the cylinder body.

The invention has the beneficial effects that:

1. according to the self-locking clamping device, a wedge-shaped space is formed among the first conical surface of the first conical block, the second conical surface of the second conical block and the front end surface of the annular table, so that a ball body in the wedge-shaped space forms a secondary force-increasing structure, the elastic body resetting elasticity at the rear end of the first conical block is amplified for the second time, the body of the annular table, namely a bearing disc, is pushed to drive the pull rod to move, the distance between the fastening head and the front plug at the front end of the pull rod is reduced, and self-locking clamping of a rotary table and the like placed between the fastening head and the front plug is realized; the clamping process is safe and reliable because the clamping of the invention does not need additional power input and artificial interference, the clamping can be kept stable for a long time after clamping without influencing the locking effect, and the force amplification factor of the clamping device is larger due to the secondary force-increasing structure.

2. The secondary force-increasing structure of the invention does not need an additional auxiliary mechanism, so the structure is more compact; under the condition of a certain clamping force, the diameter of the cylinder body and the volume of the whole clamp can be obviously reduced, or the fluid pressure during loosening can be reduced, so that the pollution of hydraulic leakage to the environment is avoided, the service life of the clamp can be prolonged, or the clamping force can be improved under the condition of a certain elastic body such as a disc spring.

3. The invention forms the second reinforcement through the interaction between the sphere and the first conical surface and the second conical surface, because the sphere is in point contact with the conical surface or in small-area elastic surface contact under high pressure, and the hardness of the sphere is high and the surface finish is good, the friction loss is smaller compared with the surface contact reinforcement mechanism tangent to the two inclined surfaces, thereby improving the force transmission efficiency.

4. The through holes are uniformly distributed on the ring platform of the pressure bearing disc to be internally provided with the slidable cylindrical pins, so that the first conical block is directly and quickly pushed by the piston through the cylindrical pins to move to compress the elastic body when the elastic body is loosened, the force required by unlocking and loosening is small, the pressure bearing disc drives the pull rod to quickly loosen a clamped object to realize quick loosening, the pressure applied to the ball body, the first conical surface and the second conical surface by the piston can be reduced, and the service life of the secondary force-increasing structure is prolonged.

In conclusion, the invention has the characteristics of compact structure, larger force amplification coefficient, small friction loss and clamping and self-locking.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a left side view of FIG. 1;

FIG. 3 is a right side view of FIG. 1;

in the figure: 1-pull rod, 2-fastening head, 3-cylinder body, 4-front plug, 5-elastomer, 6-bearing disc, 601-annular table, 7-first cone block, 8-second cone block, 9-sphere, 10-piston, 11-rear plug, 12-cylindrical pin, 13-fastening block, 14-screw and square sealing ring for 15 holes.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

As shown in fig. 1, 2 and 3, the invention comprises a pull rod 1, a fastening head 2, a cylinder body 3, a front plug 4, an elastic body 5, a pressure bearing disc 6, a first conical block 7, a second conical block 8, a sphere 9, a piston 10 and a rear plug 11, wherein the fastening head 2 is movably arranged at one side of the pull rod 1, the other side of the pull rod 1 is coaxially and fixedly arranged in the pressure bearing disc 6, the front plug 4 is arranged at the front end of the cylinder body 3 in a threaded engagement manner, the pressure bearing disc 6 is coaxially arranged in the cylinder body 3 and forms a hollow inner cavity with the front plug 4, the elastic body 5 is arranged in the hollow inner cavity and the front end is abutted against the rear end of the front plug 4, the first conical block 7 is arranged outside the pressure bearing disc 6 in a sliding manner and the front end is abutted against the rear end of the elastic body 5, the outer side of the rear end of the first conical block 7 forms a first conical surface, the second conical block 8 is arranged in the inner cavity of the stepped through hole of the cylinder body 3 at the outer side of the first conical block 7 and the front end is abutted against the stepped through hole, the rear end of the second cone block 8 is formed into a second conical surface on the inner side, the end of the pressure bearing disc 6 far away from the fastening head 2 is provided with a ring platform 601, the ball body 9 is arranged in a wedge-shaped space formed between the first conical surface, the second conical surface and the front end surface of the ring platform 601, the piston 10 is coaxially arranged in the cylinder body (3) in a sliding manner, and the rear end plug 11 is fixedly arranged at the rear end of the cylinder body 3.

At least 3 through holes are uniformly distributed in the annular table 601, cylindrical pins 12 are arranged in the through holes in a sliding mode, the length of each cylindrical pin 12 is smaller than the distance between the rear end face of each first conical block 7 and the rear end face of the annular table 601 when the ball body 9 is located at the lowest end of each first conical surface, and is larger than the distance between the rear end face of each first conical block 7 and the rear end face of the annular table 601 when the ball body 9 is located at the highest end of each first conical surface.

And a first thread section is arranged on the outer circle of one side of the pull rod 1, which is far away from the fastening head 2, and the first thread section is meshed and fixed with a threaded hole in the pressure bearing disc 6.

The rear end of the bearing disc 6 is provided with a counter bore coaxial with the threaded hole, a fastening block 13 is arranged in the counter bore, the fastening block 13 is in threaded connection with the pull rod 1 through a screw 14, and the front end of the fastening block 13 abuts against the rear end face of the pull rod 1.

One end of the pull rod 1 close to the fastening head 2 is provided with an inner triangle, inner four corners or an inner hexagonal counter bore, and the fastening head 2 is in threaded engagement with the second thread section on the excircle of the pull rod 1.

The annular table 601 is a cylindrical table coaxial with a threaded hole in the pressure bearing disc 6, and the outer circular surface of the annular table 601 is coaxially and slidably matched with the inner circular surface of the cylinder body 3.

The excircle surface of the second cone block 8 is tightly matched with the inner circle surface of the cylinder body 3, and the diameter of the inner hole of the second cone block 8 is smaller than the inner diameter of the step surface of the step through hole of the cylinder body 3.

The first conical surface of the first conical block 7 and the second conical surface of the second conical block 8 mutually form a V-shaped wedge surface with an opening facing the front end of the annular table 601.

An annular groove is coaxially arranged on the outer circular surface of the piston 10, and a square sealing ring 15 for holes is arranged in the annular groove.

The elastic body 5 is a disc spring or a rubber ring.

The working principle and the working process of the invention are as follows:

as shown in fig. 1, 2 and 3, when an object to be clamped is placed in and loosened, a hydraulic or high-pressure gas system is used for injecting high-pressure fluid into the cylinder body 3 from the rear plug 11, the piston 10 moves leftwards under the action of the high-pressure fluid, so that the cylindrical pin 12 directly pushes the first conical block 7 to move leftwards to compress the elastic body 5 (disc spring), the pressure of the fluid in the cylinder body 3 does not need to overcome the force increment formed by the secondary force increment structure, and the pressure of the fluid in the cylinder body 3 is reduced; meanwhile, as the first conical block 7 moves leftwards, the steel ball 9 moves downwards along the first conical surface of the first conical block 7, so that the pressure applied to the ball body 9, the first conical surface and the second conical surface by the piston 10 can be reduced, and the piston 10 pushes the cylindrical pin 12 and simultaneously directly pushes the bearing plate 6 to move leftwards, so that the distance between the fastening head 2 and the front plug 4 is rapidly increased, and a clamped object is convenient to loosen.

When clamping, high pressure flow in the piston 10 is released, the compressed elastic body 5 (disc spring) rebounds after losing the compression force from the piston 10, the cylindrical pin 12 is pushed to drive the piston 10 to move right, the first conical block 7 moves rightwards, the steel ball 9 moves upwards along the first conical surface under the pushing of the first conical block 7, the rebounding of the elastic body 5 (disc spring) is amplified for one time, then the steel ball 9 moves rightwards and upwards under the blocking of the second conical surface of the second conical block 8, the rebounding of the elastic body 5 (disc spring) is amplified for two times, the ring platform 601 is pushed to move rightwards under the action of the steel ball 9 moving rightwards and upwards, the ring platform 601 drives the body, namely the bearing disc 6 and the pull rod 1 connected with the bearing disc 6 to move rightwards, so that the distance between the fastening head 2 and the front plug 4 is reduced to realize clamping, and the secondarily amplified force acting on the ring platform 601 is output as clamping force through the pull rod 1 and the fastening head 2, the self-locking clamping of the object to be clamped is realized.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A double-conical-surface boosting clamping mechanism is characterized by comprising a pull rod (1), a tightening head (2), a cylinder body (3), a front plug (4), an elastic body (5), a pressure bearing disc (6), a first conical block (7), a second conical block (8), a ball body (9), a piston (10) and a rear plug (11), wherein the tightening head (2) is movably arranged on one side of the pull rod (1), the other side of the pull rod (1) is coaxially and fixedly arranged in the pressure bearing disc (6), the front plug (4) is arranged at the front end of the cylinder body (3) in a threaded engagement manner, the pressure bearing disc (6) is coaxially arranged in the cylinder body (3) and forms a hollow inner cavity with the front plug (4), the elastic body (5) is arranged in the hollow inner cavity, the front end of the elastic body is abutted against the rear end of the front plug (4), the first conical block (7) is slidably arranged outside the pressure bearing disc (6), and the front end of the first conical block is abutted against the rear end of the elastic body (5), the rear end outside of first taper block (7) forms first conical surface, second taper block (8) set up in the inner chamber of cylinder body (3) step through-hole in the first taper block (7) outside and the step terminal surface butt of front end and step through-hole, the rear end inboard of second taper block (8) forms the second conical surface, bearing disc (6) still is provided with ring platform (601) in the one end of keeping away from tight fixed head (2), spheroid (9) set up in the wedge space that forms between the preceding terminal surface of first conical surface, second conical surface and ring platform (601), piston (10) coaxial slip sets up in cylinder body (3), back end cap (11) are fixed to be set up in the rear end of cylinder body (3).

2. The double-cone boosting clamping mechanism according to claim 1, characterized in that at least 3 through holes are uniformly distributed on the annular table (601), cylindrical pins (12) are slidably arranged in the through holes, and the length of each cylindrical pin (12) is smaller than the distance between the rear end surface of the first cone block (7) and the rear end surface of the annular table (601) when the ball body (9) is located at the lowest end of the first cone surface, and is larger than the distance between the rear end surface of the first cone block (7) and the rear end surface of the annular table (601) when the ball body (9) is located at the highest end of the first cone surface.

3. The double-cone boosting clamping mechanism according to claim 1, characterized in that the outer circle of the side of the pull rod (1) far away from the fastening head (2) is provided with a first threaded section and is engaged and fixed with a threaded hole in the bearing disc (6).

4. The double-conical-surface boosting clamping mechanism is characterized in that a counter bore coaxial with a threaded hole is formed in the rear end of the bearing disc (6), a fastening block (13) is arranged in the counter bore, the fastening block (13) is in threaded connection with the pull rod (1) through a screw (14), and the front end of the fastening block (13) abuts against the rear end face of the pull rod (1).

5. The double-cone boosting clamping mechanism according to claim 3, characterized in that a counter bore with an inner triangle, an inner four corners or an inner hexagonal is arranged at one end of the pull rod (1) close to the fastening head (2), and the fastening head (2) is in threaded engagement with a second thread section on the excircle of the pull rod (1).

6. The double-cone energizing clamping mechanism according to any one of claims 1 to 5, wherein the ring platform (601) is a cylindrical platform coaxial with a threaded hole in the pressure bearing disk (6), and the outer circular surface of the ring platform (601) is coaxially and slidably engaged with the inner circular surface of the cylinder body (3).

7. The double-cone boosting clamping mechanism according to claim 6, characterized in that the outer circular surface of the second cone block (8) is tightly matched with the inner circular surface of the cylinder body (3), and the diameter of the inner hole of the second cone block (8) is smaller than the inner diameter of the step surface of the step through hole of the cylinder body (3).

8. The double-cone force-increasing clamping mechanism according to claim 7, characterized in that the first conical surface of the first cone block (7) and the second conical surface of the second cone block (8) mutually form a V-shaped wedge surface with an opening facing the front end of the annular table (601).

9. The double-cone energizing clamping mechanism according to claim 6, wherein the outer circumferential surface of the piston (10) is coaxially provided with an annular groove, and a square sealing ring (15) for holes is arranged in the annular groove.

10. The double-cone energizing clamping mechanism according to claim 6, wherein said elastomer (5) is a belleville spring or a rubber ring.