A positioning, tensioning and clamping pneumatic device

Abstract

The present invention discloses a positioning tension clamping pneumatic device, which includes a cylinder body with a cylinder hole, a piston assembly arranged in the cylinder hole, a positioning tension assembly for positioning and tension clamping a workpiece, and a pull rod connected between the piston assembly and the positioning tension assembly; the piston assembly includes a piston, a guiding module connected to the pull rod, and a plurality of rolling elements arranged between the piston and the guiding module; the rolling elements are used to be driven by the piston to extrude the guiding module, so that the pull rod drives the positioning tension assembly to position and tension clamp the workpiece; a first elastic member is arranged in the cylinder hole at the bottom of the piston, which is used to press against the piston to enable the positioning tension assembly to maintain the clamping force on the workpiece. The present invention can still maintain the clamping force after the air supply is cut off by setting the first elastic member, and has a self-locking function. At the same time, by setting a guiding sleeve, it can ensure that the positioning tension assembly has the functions of positioning and tensioning simultaneously during the tensioning process, and prevent machine collision during the handling process.

Description

Technical Field

[0001] The present invention relates to the technical field of pin clamping cylinders, and particularly to a positioning and tensioning clamping pneumatic device. Background Art

[0002] In the fields of machining and automation, when handling relatively compact workpieces with irregular surfaces, if it is necessary to clamp their surfaces, the phenomenon of unstable workpiece clamping will occur due to the irregular surfaces. Therefore, it is necessary to use the positioning pin holes of the workpiece itself for positioning and clamping, and generally a pin clamping cylinder will be selected for clamping.

[0003] However, the existing pin clamping cylinders have complex structures, and at the same time, the existing pin clamping cylinders do not have a self-locking function. There is no clamping force after the air supply is cut off, which will cause the risk of dropping. In addition, it is also necessary to ensure that there is no interference during handling or processing to reduce the risk of collision. Summary of the Invention

[0004] The purpose of the present invention is to provide a positioning and tensioning clamping pneumatic device, which can still maintain the clamping force after the air supply is cut off by setting a first elastic member, and has a self-locking function. At the same time, by setting a guide sleeve, it can ensure that the positioning and tensioning assembly has the functions of positioning and tensioning during the tensioning process, and prevent collision during handling.

[0005] To achieve the above purpose, the following technical solutions are adopted:

[0006] A positioning and tensioning clamping pneumatic device includes a cylinder body with a cylinder hole, a piston assembly arranged in the cylinder hole, a positioning and tensioning assembly for positioning, tensioning and clamping a workpiece, and a pull rod connected between the piston assembly and the positioning and tensioning assembly; the piston assembly includes a piston, a guide module connected to the pull rod, and a plurality of rolling members arranged between the piston and the guide module; the rolling members are used to drive the guide module by the piston, so that the pull rod drives the positioning and tensioning assembly to position, tension and clamp the workpiece; a first elastic member is arranged in the cylinder hole at the bottom of the piston to press against the piston so that the positioning and tensioning assembly maintains the clamping force on the workpiece.

[0007] Preferably, the positioning and tensioning assembly includes a positioning sleeve for inserting into the workpiece for positioning, a wedge block arranged in the positioning sleeve, and a finger block on each of the opposite outer sides of the wedge block, and the inner side surface of the finger block and the outer side surface of the wedge block are provided with inclined surfaces with the same inclination; a finger block moving hole is opened on the side wall of the positioning sleeve corresponding to each finger block; when the wedge block moves downward, the finger block tightens and clamps the workpiece through the corresponding finger block moving hole.

[0008] Preferably, the positioning and tensioning assembly further includes a driving column, a driving hole penetrating through to the opposite side surfaces is opened in the middle of the driving column; the wedge block is arranged in the driving hole, and the driving column is embedded in the positioning sleeve.

[0009] Preferably, a rolling groove is provided on the outer side wall of the lower part of the guiding module corresponding to each rolling element; a receiving groove for the lifting movement of the guiding module is provided at the top of the piston, and the inner side wall of the upper part of the receiving groove is circumferentially formed as a tapered surface with an opening gradually increasing from bottom to top; a wedge-shaped extrusion groove is formed between the tapered surface and each rolling groove.

[0010] Preferably, the guiding module includes a guiding block fitted on the inner wall of the cylinder hole and a locking block movably arranged inside the guiding block; the rolling groove is provided on the outer side wall of the locking block, and a limiting groove is further provided at the bottom of the guiding block corresponding to each rolling groove to limit the upward stroke of the rolling element.

[0011] Preferably, it further includes a front cover with a telescopic hole opened through both ends, the lower end of the front cover is installed on the top of the cylinder block and the telescopic hole is communicated with the cylinder hole; the pull rod is arranged in the telescopic hole along the axial direction of the front cover, and the positioning sleeve extends out of the upper end of the front cover.

[0012] Preferably, it further includes a guiding sleeve movably placed on the inner wall of the front cover, and the guiding sleeve is placed between the pull rod and the front cover; a second elastic member is provided between the bottom of the guiding sleeve and the top of the guiding block for driving the guiding sleeve to push out and reset.

[0013] Preferably, a plurality of first positioning grooves are circumferentially spaced on the outer periphery of the guiding block, and a plurality of second positioning grooves corresponding to the plurality of first positioning grooves one by one are circumferentially provided on the inner wall of the cylinder hole; a positioning steel ball is provided between each first positioning groove and a second positioning groove for limiting and fixing the guiding block.

[0014] Preferably, a first limiting boss is provided on the outer side wall of the middle part of the finger block, and a second limiting boss is provided on the outer side wall of the lower part; an elastic reset ring is sleeved on the outer periphery of the positioning sleeve, and the elastic reset ring is located between the first limiting boss and the second limiting boss; the elastic reset ring is used to retract the finger block by elastic force.

[0015] Preferably, a rear cover is detachably connected to the inner wall of the bottom of the cylinder hole, and a first sealing ring is provided between the rear cover and the inner wall of the cylinder hole; a second sealing ring is provided between the outer periphery of the guiding block and the inner wall of the cylinder hole.

[0016] Adopting the above solution, the beneficial effects of the present invention are:

[0017] The present invention provides a positioning tension clamping pneumatic device, which can maintain the clamping force through the first elastic member even after the air supply is cut off, and has a self-locking function. At the same time, by setting the guide sleeve, it can ensure that the positioning tension assembly has the functions of positioning and tensioning during the tensioning process, prevent machine collision during handling, and the guide sleeve can automatically reset under the action of the second elastic member. In addition, by setting the wedge block and the wedge extrusion groove, multiple wedge structures are used to increase the tension force, which can efficiently clamp and fix during clamping, and there is no need to worry about the workpiece falling due to insufficient clamping force. It has a compact structure and is easy to install, and can clamp larger workpieces in a limited space. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a perspective view of the present invention;

[0019] Figure 2 is an exploded view of the present invention;

[0020] Figure 3 is a sectional view of the present invention;

[0021] Figure 4 is an exploded view of the piston assembly of the present invention;

[0022] Figure 5 is an exploded view of the positioning tension assembly of the present invention;

[0023] Figure 6 is a schematic diagram of the present invention before the finger block is tensioned and before the workpiece is tensioned;

[0024] Figure 7 is a schematic diagram of the present invention after the finger block is tensioned and before the workpiece is tensioned;

[0025] Figure 8 is a schematic diagram of the present invention after the finger block is tensioned and after the workpiece is tensioned;

[0026] Among them, the description of the reference numerals in the drawings:

[0027] 1 - cylinder block, 2 - piston assembly,

[0028] 3 - positioning tension assembly, 4 - pull rod,

[0029] 5 - first elastic member, 6 - front cover,

[0030] 7 - guide sleeve, 8 - second elastic member,

[0031] 9 - positioning steel ball, 10 - rear cover,

[0032] 11 - first sealing ring, 12 - second sealing ring,

[0033] 13 - workpiece, 21 - piston,

[0034] 22 - rolling element, 23 - rolling groove,

[0035] 24 - guiding block, 25 - locking block,

[0036] 26 - limiting groove, 31 - positioning sleeve,

[0037] 32 - wedge block, 33 - finger block,

[0038] 34 - driving column, 35 - first limiting boss,

[0039] 36 - second limiting boss, 37 - elastic reset ring. Detailed implementation manners

[0040] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that for the convenience of description, only parts related to the present invention rather than all structures are shown in the drawings.

[0041] In the description of the present invention, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0042] In the present invention, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "above and over", and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "below and under", and "under" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0043] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0044] Reference Figures 1 to 8 As shown, the present invention provides a positioning, tightening and clamping pneumatic device to solve the problem that the clamping jaws are too large and too heavy in the working environment of the manipulator grasping a large workpiece, including a cylinder body 1 with a cylinder hole, a piston assembly 2 arranged in the cylinder hole, a positioning, tightening and clamping assembly 3 for positioning, tightening and clamping the workpiece 13, and a pull rod 4 connected between the piston assembly 2 and the positioning, tightening and clamping assembly 3; the piston assembly 2 includes a piston 21, a guide module connected to the pull rod 4, and a plurality of rolling elements 22 arranged between the piston 21 and the guide module; specifically, the rolling element 22 uses a transmission steel ball, and the transmission steel ball realizes the transmission function. The rolling element 22 is used to be driven by the piston 21 to squeeze the guide module, so that the pull rod 4 drives the positioning, tightening and clamping assembly 3 to position, tighten and clamp the workpiece 13.

[0045] In addition, a first elastic member 5 is provided in the cylinder hole at the bottom of the piston 21, which is used to press the piston 21 so that the positioning tensioning assembly 3 maintains the clamping force on the workpiece 13. Specifically, the first elastic member 5 is a spring, and ventilation drives the piston 21 to press the first elastic member 5 downward and retreat, thereby driving the pull rod 4 to be pushed out.

[0046] The positioning and tightening assembly 4 includes a positioning sleeve 31 for inserting the workpiece 13 for positioning, a wedge block 32 arranged in the positioning sleeve 31, and a finger block 33 arranged on both sides of the wedge block 32, and the inner side surface of the finger block 33 and the outer side surface of the wedge block 32 are provided with inclined surfaces with the same inclination; the side wall of the positioning sleeve 31 is provided with a finger block movable hole corresponding to each finger block 33; when the wedge block 32 moves downward, the finger block 33 tightens and clamps the workpiece 13 through the corresponding finger block movable hole. When the finger block 33 is inserted into the positioning pin hole of the workpiece 13, the spring force of the first elastic member 5 and the air pressure act on the piston 21 at the same time, thereby expanding the finger block 33, having a strong tightening force, and having a certain tightening force even after the gas is cut off, realizing the self-locking function.

[0047] The positioning and tightening assembly 3 further includes a driving column 34, a driving hole penetrating to two opposite sides is opened in the middle of the driving column 34; the wedge block 32 is arranged in the driving hole, and the driving column 34 is embedded in the positioning sleeve 31. The wedge block 32 and the driving column 34 are integrally formed, and the upper end of the pull rod 4 is detachably connected to the driving column 34.

[0048] On the outer side wall of the lower part of the guiding module, a rolling groove 23 is provided corresponding to each rolling element 22. In a specific embodiment, four rolling grooves 23 are provided to cooperate with four transmission steel balls for transmission, so as to make the finger block 33 expand and tighten outward. On the top of the piston 21, a receiving groove for the lifting movement of the guiding module is provided, and the inner side wall of the upper part of the receiving groove is circumferentially provided with a conical surface with an opening gradually increasing from bottom to top. A wedge-shaped extrusion groove is formed between the conical surface and each rolling groove 23. The guiding module includes a guiding block 24 fitted on the inner wall of the cylinder hole and a locking block 25 movably arranged inside the guiding block 24. The locking block 25 is movably arranged through the guiding block 24, and the lower end of the pull rod 4 is detachably connected to the locking block 25. The rolling groove 23 is provided on the outer side wall of the locking block 25, and a limiting groove 26 is also provided on the bottom of the guiding block 24 corresponding to each rolling groove 23 to limit the upward travel of the rolling element 22.

[0049] Specifically, the wedge-shaped block 32 is arranged with a larger upper part and a smaller lower part, and the wedge-shaped extrusion groove is also with a larger upper part and a smaller lower part. When the piston 21 moves upward so that its conical surface squeezes the rolling element 22 against the rolling groove 23, the rolling element 22 exerts a downward pressure on the locking block 25 to drive the pull rod 4 to move downward. When the wedge-shaped block 32 moves downward following the pull rod 4, it can squeeze the finger block 33 to expand and tighten outward to clamp the positioning pin hole of the workpiece 13. The outward expansion and tightening of the finger block 33 applies a wedge-shaped block 32, and at the same time, the piston 21 cooperates with the rolling element 22 to further tighten the pull rod 4 by applying the wedge-shaped extrusion groove. The rolling element 22 exerts a downward pressure on the locking block 25 to drive the pull rod 4 to move downward, and by reducing the displacement amount, the output force is increased to achieve a strong multiple force output and a strong tightening force, and the overall structure is compact. Of course, when ensuring the multiple force output, it is necessary to ensure its positioning and clamping function.

[0050] It further includes a front cover 6 with telescopic holes opened at both ends. The lower end of the front cover 6 is installed on the top of the cylinder block 1 and the telescopic holes are communicated with the cylinder hole. The front cover 6 is locked to the top of the cylinder block 1 by screws. The pull rod 4 is arranged in the telescopic hole along the axial direction of the front cover 6, and the positioning sleeve 31 extends out of the upper end of the front cover 6.

[0051] It further includes a guiding sleeve 7 movably placed on the inner wall of the front cover 6, and the guiding sleeve 7 is placed between the pull rod 4 and the front cover 6. A second elastic member 8 is provided between the bottom of the guiding sleeve 7 and the top of the guiding block 24 to drive the guiding sleeve 7 to push out and reset. Specifically, the second elastic member 8 adopts a spring.

[0052] A plurality of first positioning grooves are circumferentially spaced on the outer periphery of the guiding block 24, and a plurality of second positioning grooves corresponding to the plurality of first positioning grooves one by one are circumferentially provided on the inner wall of the cylinder hole. A positioning steel ball 9 is provided between each first positioning groove and a second positioning groove to limit and fix the guiding block 24.

[0053] A first limiting boss 35 is provided on the outer side wall of the middle part of the finger block 33, and a second limiting boss 36 is provided on the outer side wall of the lower part; an elastic reset ring 37 is sleeved on the outer circumference of the positioning sleeve 31, and the elastic reset ring 37 is located between the first limiting boss 35 and the second limiting boss 36. In a specific embodiment, the elastic reset ring 37 is a rubber ring with certain elasticity, and is used to retract the finger block 33 by elastic force when the finger block 33 needs to retract and reset after being tightened. By providing the first limiting boss 35 and the second limiting boss 36, the elastic reset ring 37 can be effectively prevented from swinging up and down. When the workpiece 13 needs to be released, the piston assembly 2 descends, thereby driving the wedge block 32 to rise, and the elastic reset ring 37 retracts the finger block 33 by elastic force.

[0054] A rear cover 10 is detachably connected to the inner wall of the bottom of the cylinder hole, and a first sealing ring 11 is provided between the rear cover 10 and the inner wall of the cylinder hole; a second sealing ring 12 is provided between the outer circumference of the guide block 24 and the inner wall of the cylinder hole. Two ends of the second elastic member 8 respectively abut against the bottom of the piston 21 and the rear cover 10. The bottom of the cylinder hole is sealed by the first sealing ring 11, and the top of the cylinder hole is sealed by the second sealing ring 12, so that a sealed space is formed in the cylinder hole.

[0055] As Figure 6 shown, when the positioning and tightening assembly 3 is in the release state, the finger block 33 retracts, and there is a certain margin for the finger block 33 in the positioning pin hole of the workpiece 13, which can ensure the insertion of the workpiece 13 even when the positioning is not so accurate. When tightening and clamping the positioning pin hole of the workpiece 13, a downward pulling force is generated at the same time to tighten the workpiece 13, ensuring that the positioning of the workpiece 13 is accurate enough during movement and placement.

[0056] That is to say, before the finger block 33 is tightened in place, the piston assembly 2 drives the pull rod 4 to pull down. At this time, the wedge block 32 moves downward to make the finger block 33 tighten the positioning pin hole of the workpiece 13, but the guide sleeve 7 remains stationary; after the finger block 33 is tightened in place, the pull rod 4 continues to pull down to drive the guide sleeve 7 and the positioning and tightening assembly 3 to continue to move downward. At this time, since the positioning pin hole of the workpiece 13 has been tightened and clamped by the finger block 33, the workpiece 13 will follow the positioning and tightening assembly 3 to move downward, and then the workpiece 13 can be pulled to fit the top end surface of the front cover 6 to achieve the positioning and tightening function, preventing the machine from being damaged during handling.

[0057] Please continue to refer to Figures 6 to 8 , in which Figure 6 shows the positional relationship among the finger block 33, the front cover 6, and the workpiece 13 before the finger block 33 is tightened and before the workpiece 13 is tightened. At this time, the finger block 33 is in the retracted state, and there is a certain gap between the workpiece 13 and the top end surface of the front cover 6, and this gap is generally less than 0.5 mm; Figure 7It shows the positional relationship among the finger block 33, the front cover 6 and the workpiece 13 after the finger block 33 is tightened and before the workpiece 13 is tightened. At this time, the finger block 33 is in a tightened state, and there is a certain gap between the workpiece 13 and the top surface of the front cover 6; Figure 8 It shows the positional relationship among the finger block 33, the front cover 6 and the workpiece 13 after the finger block 33 is tightened and the workpiece 13 is tightened. At this time, the finger block 33 is in a tightened state, and the workpiece 13 is in close contact with the top surface of the front cover 6.

[0058] A positioning and tightening clamping pneumatic device provided by the present invention has a self-locking function and a positioning and tightening function, and performs handling operations by clamping in a limited space. The structure is compact, and it will not occupy a large clamping space due to the large size of the device, nor will the workpiece 13 fall due to insufficient clamping force.

[0059] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. Obviously, the above embodiments of the present invention are only examples for clearly explaining the present invention and are not limitations on the implementation manners of the present invention. For those of ordinary skill in the art, various obvious changes, re-adjustments, and replacements can be made without departing from the protection scope of the present invention. It is not necessary and impossible to enumerate all the implementation manners here. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A positioning, tensioning and clamping pneumatic device, characterized in that, It includes a cylinder block with cylinder bores, a piston assembly arranged in the cylinder bores, a positioning and tightening assembly for positioning and tightening the clamped workpiece, and a pull rod connected between the piston assembly and the positioning and tightening assembly; the piston assembly includes a piston, a guiding module connected to the pull rod, and a number of rolling elements arranged between the piston and the guiding module; the rolling elements are used to drive the guiding module by the piston to extrude, so that the pull rod drives the positioning and tightening assembly to position and tighten the clamped workpiece; a first elastic element is arranged in the cylinder bore at the bottom of the piston, which is used to press the piston to keep the positioning and tightening assembly clamping force on the workpiece; The positioning and tightening assembly includes a positioning sleeve for inserting into the workpiece for positioning, a wedge block arranged in the positioning sleeve, and a finger block arranged on each of the opposite outer sides of the wedge block, and the inner side surface of the finger block and the outer side surface of the wedge block are provided with inclined surfaces with the same inclination; a finger block moving hole is opened on the side wall of the positioning sleeve corresponding to each finger block; when the wedge block moves downward, the finger block tightens and clamps the workpiece through the corresponding finger block moving hole; The guiding module includes a guiding block fitted on the inner wall of the cylinder bore and a locking block movably arranged inside the guiding block; It also includes a front cover with a telescopic hole opened through both ends, the lower end of the front cover is installed on the top of the cylinder block and the telescopic hole is communicated with the cylinder bore; the pull rod is arranged in the telescopic hole along the axial direction of the front cover, and the positioning sleeve extends out of the upper end of the front cover; It also includes a guiding sleeve movably placed on the inner wall of the front cover, and the guiding sleeve is placed between the pull rod and the front cover; a second elastic element is arranged between the bottom of the guiding sleeve and the top of the guiding block, which is used to drive the guiding sleeve to push out and reset; Before the finger block is tightened in place, the pull rod drives the wedge block to extrude the finger block through the guiding sleeve to realize outward tightening; After the finger block is tightened in place, the pull rod drives the positioning and tightening assembly and the guiding sleeve to move together to realize positioning and tightening of the workpiece.

2. The positioning, tensioning and clamping pneumatic device according to claim 1, characterized in that, The positioning and tightening assembly also includes a driving column, a driving hole penetrating through the opposite side surfaces is opened in the middle of the driving column; the wedge block is arranged in the driving hole, and the driving column is embedded in the positioning sleeve.

3. The positioning, tensioning and clamping pneumatic device according to claim 1, characterized in that, A rolling groove is opened on the outer side wall of the lower part of the guiding module corresponding to each rolling element; a receiving groove for the lifting and moving of the guiding module is opened on the top of the piston, and the inner side wall of the upper part of the receiving groove is circumferentially opened as a conical surface with an opening gradually increasing from bottom to top; a wedge-shaped extrusion groove is formed between the conical surface and each rolling groove.

4. The positioning, tensioning and clamping pneumatic device according to claim 3, characterized in that, The rolling groove is opened on the outer side wall of the locking block, and a limiting groove is also opened on the bottom of the guiding block corresponding to each rolling groove to limit the rising stroke of the rolling element.

5. The positioning, tensioning and clamping pneumatic device according to claim 4, characterized in that, A number of first positioning grooves are circumferentially spaced on the outer circumference of the guiding block, and a number of second positioning grooves corresponding to the number of first positioning grooves one by one are circumferentially opened on the inner wall of the cylinder bore; a positioning steel ball is arranged between each first positioning groove and a second positioning groove to limit and fix the guiding block.

6. The positioning, tensioning and clamping pneumatic device according to claim 1, characterized in that, A first limiting boss is arranged on the outer side wall of the middle part of the finger block, and a second limiting boss is arranged on the outer side wall of the lower part; an elastic reset ring is sleeved on the outer circumference of the positioning sleeve, and the elastic reset ring is located between the first limiting boss and the second limiting boss; the elastic reset ring is used to retract the finger block by elastic force.

7. The positioning, tensioning and clamping pneumatic device according to claim 4, characterized in that, A rear cover is detachably connected to the inner wall of the bottom of the cylinder bore, and a first sealing ring is provided between the rear cover and the inner wall of the cylinder bore; a second sealing ring is provided between the outer circumference of the guide block and the inner wall of the cylinder bore.

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