CN113211200A - Piston pin grinding device for machining - Google Patents
Piston pin grinding device for machining Download PDFInfo
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- CN113211200A CN113211200A CN202110577361.2A CN202110577361A CN113211200A CN 113211200 A CN113211200 A CN 113211200A CN 202110577361 A CN202110577361 A CN 202110577361A CN 113211200 A CN113211200 A CN 113211200A
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- China
- Prior art keywords
- supporting plate
- piston pin
- electromagnet
- polishing
- spacer
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B5/00—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor
- B24B5/02—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor involving centres or chucks for holding work
- B24B5/06—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor involving centres or chucks for holding work for grinding cylindrical surfaces internally
- B24B5/08—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor involving centres or chucks for holding work for grinding cylindrical surfaces internally involving a vertical tool spindle
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B27/00—Other grinding machines or devices
- B24B27/0023—Other grinding machines or devices grinding machines with a plurality of working posts
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B27/00—Other grinding machines or devices
- B24B27/0076—Other grinding machines or devices grinding machines comprising two or more grinding tools
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B27/00—Other grinding machines or devices
- B24B27/0084—Other grinding machines or devices the grinding wheel support being angularly adjustable
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B41/00—Component parts such as frames, beds, carriages, headstocks
- B24B41/06—Work supports, e.g. adjustable steadies
- B24B41/067—Work supports, e.g. adjustable steadies radially supporting workpieces
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B47/00—Drives or gearings; Equipment therefor
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B47/00—Drives or gearings; Equipment therefor
- B24B47/10—Drives or gearings; Equipment therefor for rotating or reciprocating working-spindles carrying grinding wheels or workpieces
- B24B47/12—Drives or gearings; Equipment therefor for rotating or reciprocating working-spindles carrying grinding wheels or workpieces by mechanical gearing or electric power
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B47/00—Drives or gearings; Equipment therefor
- B24B47/10—Drives or gearings; Equipment therefor for rotating or reciprocating working-spindles carrying grinding wheels or workpieces
- B24B47/14—Drives or gearings; Equipment therefor for rotating or reciprocating working-spindles carrying grinding wheels or workpieces by liquid or gas pressure
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B47/00—Drives or gearings; Equipment therefor
- B24B47/10—Drives or gearings; Equipment therefor for rotating or reciprocating working-spindles carrying grinding wheels or workpieces
- B24B47/16—Drives or gearings; Equipment therefor for rotating or reciprocating working-spindles carrying grinding wheels or workpieces performing a reciprocating movement, e.g. during which the sense of rotation of the working-spindle is reversed
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B47/00—Drives or gearings; Equipment therefor
- B24B47/22—Equipment for exact control of the position of the grinding tool or work at the start of the grinding operation
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B5/00—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor
- B24B5/02—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor involving centres or chucks for holding work
- B24B5/04—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor involving centres or chucks for holding work for grinding cylindrical surfaces externally
- B24B5/047—Machines or devices designed for grinding surfaces of revolution on work, including those which also grind adjacent plane surfaces; Accessories therefor involving centres or chucks for holding work for grinding cylindrical surfaces externally of workpieces turning about a vertical axis
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B9/00—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor
- B24B9/02—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground
- B24B9/04—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground of metal, e.g. skate blades
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)
Abstract
The invention relates to the technical field of polishing devices, in particular to a piston pin polishing device for machining, which comprises a base, wherein an air compressor is fixedly connected right above the base, a first supporting plate is arranged right above the base, the base is fixedly connected with the first supporting plate through a supporting rod, a second supporting plate is arranged right above the first supporting plate, and the first supporting plate is connected with the second supporting plate through a transmission rod; according to the invention, the chamfer of the piston pin inner ring is polished through the mutual matching of the first electromagnet, the second electromagnet, the third electromagnet, the pneumatic telescopic rod, the spring and the like, so that the problem that the chamfer of the piston pin inner ring needs to be polished by other manpower or by using special polishing equipment alone is solved, the occupied space is reduced, and the equipment investment cost is reduced.
Description
Technical Field
The invention relates to the technical field of polishing devices, in particular to a piston pin polishing device for machining.
Background
The piston pin is a cylindrical pin mounted on the skirt of the piston. The middle part of the connecting rod passes through a small end hole of the connecting rod and is used for connecting the piston and the connecting rod, and the function of the connecting rod is to transmit the gas acting force borne by the piston to the connecting rod or to enable the small end of the connecting rod to drive the piston to move together. To reduce weight, piston pins are typically made of high quality alloy steel and machined to be hollow. As a part commonly used on machinery, the piston pin has huge demand, so that a large amount of production and processing are obtained; in the course of working, often need to process the outside of the piston pin of preliminary production and polish, if the outside of piston pin is crude can influence the result of use of piston pin, therefore the grinding device for piston pin just appears very important. However, traditional piston pin grinding device for machining is in the use, because grinding device's single structure, therefore polish at every turn and all can only polish single size's piston pin, and current piston pin surface and inner bore wall are polished and are adopted two sets of equipment to polish, need transport between two equipment and realize the continuity of polishing, the time will be wasted in the transportation of piston pin between equipment, thereby lead to polishing inefficiency, to this problem, a novel piston pin grinding device can be proposed, the efficiency of processing of polishing to the piston pin is improved.
Disclosure of Invention
The invention aims to provide a piston pin polishing device for machining, and solves the problem that in the prior art, the polishing efficiency of a piston pin is low.
In order to achieve the purpose, the invention adopts the following technical scheme: a piston pin polishing device for machining comprises a base, wherein an air compressor is fixedly connected right above the base, an exhaust pipeline of the air compressor is communicated with an air storage tank, a first supporting plate is arranged right above the base, the base is fixedly connected with the first supporting plate through a supporting rod, a second supporting plate is arranged right above the first supporting plate, the first supporting plate is connected with the second supporting plate through a transmission rod, and a plurality of polishing assemblies distributed in an annular array mode by taking a central shaft of the transmission rod as a center are arranged between the first supporting plate and the second supporting plate; the peripheral side surface of the transmission rod is provided with a driving gear; the top end of the second supporting plate is fixedly connected with a servo motor through a bolt, and an output shaft of the servo motor penetrates through the second supporting plate to be in transmission connection with the transmission rod and is in rotary connection with the second supporting plate at the penetrating position;
the polishing assembly comprises a first connecting rod and a pneumatic telescopic rod, the first connecting rod is rotatably connected with a second supporting plate, a driven gear is arranged on the peripheral side face of the first connecting rod, a sliding groove is formed in the bottom end of the first connecting rod, a spacer is arranged in the middle of the sliding groove, sliding assemblies are arranged on two sides of the spacer and are connected with the spacer through springs, and a first electromagnet is arranged at the bottom of each sliding assembly; a polishing layer is arranged on the peripheral side surface of the first electromagnet;
pneumatic telescopic link and first backup pad fixed connection just pneumatic telescopic link and the coincidence of first connecting rod axis, pneumatic telescopic link top fixed mounting has the mount pad, two of mount pad top fixedly connected with fixed plate, two the fixed plate symmetric distribution, and two the fixed plate all is connected with semi-circular polishing piece through pneumatic connecting rod, pneumatic connecting rod and semi-circular polishing piece are connected, pneumatic connecting rod and pneumatic telescopic link all communicate with the gas holder through vent line, be equipped with pressure sensor between semi-circular polishing piece and the pneumatic connecting rod.
According to the preferable technical scheme, a protective cover is arranged on the outer side of the first supporting plate, the protective cover is of a cylindrical structure matched with the first supporting plate, the top of the protective cover is of an open structure, the bottom of the protective cover is provided with an opening matched with the supporting rod, three clamping pieces are fixedly connected to the inner portion of the protective cover, clamping grooves matched with the clamping pieces are formed in the outer wall of the first supporting plate, the three clamping grooves are distributed in a circular array, the center of the array is located on the center shaft of the first supporting plate, the protective cover and the first supporting plate are in sliding connection through matching of the clamping pieces and the clamping pieces, the bottom ends of the clamping pieces are fixedly connected with the base through pneumatic telescopic components, and an observation window made of transparent materials is arranged on the wall of the protective cover.
As the preferable technical scheme of the invention, the mounting seat is provided with a vent hole; the air vent is communicated with a filter chamber through an air passage, and the filter chamber is communicated with an air inlet pipeline of the air compressor.
As a preferred technical scheme, the polishing layer is arranged on the upper end surface of the mounting seat, and the polishing layer on the mounting seat is connected with the upper end surface of the mounting seat through a sticky buckle.
As a preferred technical scheme of the invention, the filter chamber comprises a recovery box, the recovery box is movably arranged at the top end of the filter chamber, a bottom plate of the recovery box is an electromagnetic filter screen, the recovery box is positioned at an air inlet of the filter chamber, and activated carbon is arranged at the bottom of the recovery box.
As a preferable technical scheme, the sliding assembly comprises two vertical plates, a T-shaped cross beam is arranged between the two vertical plates, two sides of the T-shaped cross beam are rotatably connected with the two vertical plates, the bottom end of a lower support leg of the T-shaped cross beam is fixedly connected with a first electromagnet, and the side face of the lower support leg of the T-shaped cross beam is connected with a spacer through a spring.
As a preferable technical scheme, one end of a spring on the left side of the spacer is connected with the side face of the lower support of the T-shaped cross beam, the other end of the spring on the left side of the spacer is connected with a second electromagnet, the second electromagnet is fixedly connected with the spacer, one end of a spring on the right side of the spacer is connected with the side face of the lower support of the T-shaped cross beam, the other end of the spring on the right side of the spacer is connected with a third electromagnet, the third electromagnet is fixedly connected with the spacer, and the bottom heights of the second electromagnet and the third electromagnet are lower than the top height of the first electromagnet.
According to the preferable technical scheme, the circumferential side face of the mounting seat is provided with a blanking assembly, the blanking assembly comprises a blanking plate, the blanking plate is located in a gap between the two semicircular polishing sheets and corresponds to the gap, an output shaft of the servo motor is provided with a slot, and the inner circumferential side face of the second supporting plate is provided with an electromagnetic plug pin which is in plug-in fit with the slot.
The invention has at least the following beneficial effects:
1. according to the invention, through the mutual cooperation of the pneumatic telescopic rod, the semicircular polishing piece, the first electromagnet and the like, the outer surface of the piston pin is rubbed with the semicircular polishing piece in the rotation process of the piston pin, so that the outer surface of the piston pin is polished, when gas supply to the pneumatic connecting rod is started, the pneumatic telescopic rod is circularly exhausted and inflated at the same time, so that the pneumatic telescopic rod moves up and down, the pneumatic telescopic rod moves up and down to drive the semicircular polishing piece to move up and down, and the semicircular polishing piece simultaneously moves up and down while the piston pin rotates, so that the outer surface of the piston pin is polished at multiple angles in the circumferential and radial directions, the outer surface of the polished piston pin is smoother and more round, the polishing time and cost are saved, and the polishing efficiency and quality of products are effectively improved.
2. According to the invention, the chamfer of the piston pin inner ring is polished through the mutual matching of the first electromagnet, the second electromagnet, the third electromagnet, the pneumatic telescopic rod, the spring and the like, so that the problem that the chamfer of the piston pin inner ring needs to be polished by other manpower or by using special polishing equipment alone is solved, the occupied space is reduced, and the equipment investment cost is reduced.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic view of the overall structure of the present invention;
FIG. 2 is a schematic view of a grinding assembly according to the present invention;
FIG. 3 is a schematic top view of the mounting base of the present invention;
FIG. 4 is an overall view of embodiment 2 of the present invention;
fig. 5 is a schematic structural diagram of a first support plate according to embodiment 2 of the present invention;
FIG. 6 is a schematic view of the protective cover and the inner structure of the embodiment 2 of the present invention;
FIG. 7 is a left side sectional view of the first link and the sliding assembly of the present invention;
FIG. 8 is a front sectional view of the first link and the sliding assembly of the present invention;
FIG. 9 is a schematic view showing the structural cooperation of the first link, the sliding assembly, the first electromagnet, the second electromagnet and the third electromagnet in embodiment 3 of the present invention;
fig. 10 is a schematic structural view of a blanking assembly and a mounting seat in embodiment 3 of the present invention.
In the figure: 1. a base; 2. a first support plate; 3. a transmission rod; 4. a driving gear; 5. a fastener; 6. a card slot; 7. an observation window; 8. a protective cover; 9. an air compressor; 10. a strut 11, a second support plate; 12. a servo motor; 13. polishing the assembly; 1301. a first link; 1302. a pneumatic telescopic rod; 1303. a driven gear; 1304. a chute; 1305. a spacer; 1306. a sliding assembly 1307 and a first electromagnet; 1308. a mounting seat; 1309. a fixing plate; 1310. a vent hole; 1311. a pneumatic connecting rod; 1312. grinding a semicircular piece; 1313. a second electromagnet; 1314. a third electromagnet; 14. and a blanking assembly.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is 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.
Example 1:
referring to fig. 1-3, a piston pin polishing device for machining comprises a base 1, wherein an air compressor 9 is fixedly connected right above the base 1, an exhaust pipeline of the air compressor 9 is communicated with an air storage tank, a first supporting plate 2 is arranged right above the base 1, the base 1 is fixedly connected with the first supporting plate 2 through a supporting rod 10, a second supporting plate 11 is arranged right above the first supporting plate 2, the first supporting plate 2 is connected with the second supporting plate 11 through a transmission rod 3, and a plurality of polishing assemblies 13 distributed in an annular array mode by taking a central shaft of the transmission rod 3 as a center are arranged between the first supporting plate 2 and the second supporting plate 11; the peripheral side surface of the transmission rod 3 is provided with a driving gear 4; the top end of the second supporting plate 11 is fixedly connected with a servo motor 12 through a bolt, and an output shaft of the servo motor 12 penetrates through the second supporting plate 11 to be in transmission connection with the transmission rod 3 and is in rotary connection with the second supporting plate 11 at the penetrating position; the transmission rod 3 penetrates through the first supporting plate 2 and drives the air compressor 9 to operate.
The grinding assembly 13 comprises a first connecting rod 1301 and a pneumatic telescopic rod 1302, the first connecting rod 1301 is rotatably connected with the second supporting plate 11, a driven gear 1303 is arranged on the peripheral side face of the first connecting rod 1301, a sliding groove 1304 is arranged at the bottom end of the first connecting rod 1301, a spacer 1305 is arranged in the middle of the sliding groove 1304, sliding assemblies 1306 are arranged on two sides of the spacer 1305 and are connected with the spacer 1305 through springs, a first electromagnet 1307 is arranged at the bottom of each sliding assembly 1306, and a grinding layer is arranged on the peripheral side face of each first electromagnet 1307; the plurality of grinding assemblies 13 are arranged, so that a plurality of piston pins with various sizes can be simultaneously ground, and the machining efficiency is effectively improved.
Pneumatic telescopic link 1302 and 2 fixed connection of first backup pad and pneumatic telescopic link 1302 and the coincidence of first link 1301 axis, pneumatic telescopic link 1302 top fixed mounting has mount pad 1308, two fixed plates 1309 of mount pad 1308 top fixedly connected with, two fixed plates 1309 symmetric distribution, and two fixed plates 1309 all are connected with semi-circular polishing piece 1312 through pneumatic connecting rod 1311, pneumatic connecting rod 1311 is connected with semi-circular polishing piece 1312, pneumatic connecting rod 1311 passes through vent line and gas holder intercommunication, all be equipped with one-way air valve and aperture governing valve in the vent line, be equipped with pressure sensor between semi-circular polishing piece 1312 and the pneumatic connecting rod 1311.
The upper end surface of the mounting base 1308 is provided with a polishing layer, and the polishing layer on the mounting base 1308 is connected with the upper end surface of the mounting base 1308 through a thread gluing. The end of the piston pin can be polished by arranging the polishing layer, and the polishing layer on the mounting seat 1308 can be replaced conveniently by arranging the thread gluing.
The mounting base 1308 is provided with a vent hole 1310; the ventilation hole 1310 is communicated with a filter chamber through an air passage, and the filter chamber is communicated with an air inlet pipeline of the air compressor 9. Through mutually supporting between air vent 1310, air flue, filter chamber, air compressor machine 9 etc. make when satisfying air compressor machine 9's the demand of admitting air the piece and the dust suction filter chamber that polish away semicircular grinding piece 1312, the effectual metal piece density that has reduced in the air improves operational environment. The air entering the air compressor 9 is guaranteed to be clean air through the arrangement of the filter chamber, and the abraded chips and dust are prevented from damaging the air compressor 9.
The filter chamber is including retrieving the box, retrieves box movable mounting at the inlet end of filter chamber, retrieves the bottom plate of box and is even interval distribution's electromagnetic plate, retrieves the box bottom and is equipped with the active carbon. Through the mutual cooperation of retrieving box, electromagnetic plate etc. the realization is retrieved reuse to the metal dust that grinds away. Through the active carbon setting, realize the absorption to non-metallic dust, avoid the dust to cause the damage to air compressor machine 9.
When the grinding device is used, firstly, piston pins with different models and sizes are placed on the mounting seat 1308, the central axis of the piston pin is overlapped with the central axis of the mounting seat 1308, then the servo motor 12 is started, the servo motor 12 drives the transmission rod 3 to start rotating, the transmission rod 3 drives the piston of the air compressor 9 to run back and forth, compressed air of the air compressor 9 enters the air storage tank through a pipeline, the two first electromagnets 1307 generate magnetic attraction by controlling the magnetism of the two first electromagnets 1307 through the control module, the two sliding assemblies 1306 approach to the partition 1306 and extrude the spring under the action of the magnetic attraction, the spring is compressed, the two first electromagnets 1307 are attracted together, the control module enables the pneumatic telescopic rod 1302 to extend for a fixed length through controlling the air pressure in the pneumatic telescopic rod 1302, wherein the fixed length is the distance from the mounting seat 1308 to the lower end face of the first electromagnet 1307, the pneumatic telescopic rod 1302 extends to push the mounting base 1308 to move upwards, so that the first electromagnet 1307 is inserted into the inner hole of the piston pin, when the lower end face of the first electromagnet 1307 is in contact with the mounting base 1308, the pneumatic telescopic rod 1302 stops extending, the control module controls the magnetism of the two first electromagnets 1307 to generate magnetic repulsion between the two first electromagnets 1307, under the combined action of the magnetic repulsion and the spring elasticity, the sliding assembly 1306 moves towards the direction away from the partition 1306, and because the two first electromagnets 1307 are both provided with magnetism, the two first electromagnets 1307 are fixedly connected with the inner hole wall of the piston pin, the servo motor 12 drives the first connecting rod 1301 to rotate through the transmission rod 3 and the driving gear 4, the first connecting rod 1301 drives the sliding assembly 1306 and the first electromagnet 1307 to rotate, the control module enables the pneumatic connecting rod 1311 to extend and push the two semicircular grinding plates to move towards the piston pin 1311 by controlling the air inflow of the pneumatic connecting rod 1311, after the semicircular grinding piece 1312 presses the piston pin, the pressure value of the pressure sensor is increased, when the pressure value of the pressure sensor on one side is equal to a preset value, the gas supply to the pneumatic connecting rod 1311 is stopped, the preset value is set according to the actual production requirement, each grinding assembly 13 has a respective preset value to adapt to piston pins with different sizes, as the piston pin is pressed by the semicircular grinding piece 1312, the piston pin and the semicircular grinding piece 1312 have relative rotation motion, in the rotation process of the piston pin, the outer surface of the piston pin rubs with the semicircular grinding piece 1312 to grind the outer surface of the piston pin, when the gas supply to the pneumatic connecting rod 1311 is started, the pneumatic telescopic rod 1302 performs circular exhaust and inflation operation, so that the pneumatic telescopic rod 1302 moves up and down, the pneumatic telescopic rod 1302 moves up and down to drive the semicircular grinding piece 1312 to move up and down, and as the piston pin rotates and the semicircular grinding piece 1312 moves up and down simultaneously, therefore, the outer surface of the piston pin is polished at multiple angles in the circumferential direction and the radial direction, the polished outer surface of the piston pin is smoother and more round, polishing time and cost are saved, and polishing efficiency and quality of products are effectively improved.
When the inner hole of the piston pin needs to be polished, the control module controls the magnetism of the two first electromagnets 1307 to enable the magnetism of the two first electromagnets 1307 to disappear or reduce, the control module controls the air inflow of the pneumatic connecting rod 1311, the pneumatic connecting rod 1311 extends and pushes the two semicircular polishing pieces 1312 to move towards the piston pin direction, the piston pin is clamped by the two semicircular polishing pieces 1312 to enable the piston pin to be kept fixed, then under the action of spring force or the two first electromagnets 1307, the polishing layers on the circumferential sides of the two first electromagnets 1307 are in contact with the inner side surface of the piston pin and move in the circumferential direction, and therefore the polishing layers on the circumferential sides of the two first electromagnets 1307 polish the inner side surface of the piston pin. Simultaneously, the pneumatic telescopic rod 1302 is controlled to circularly exhaust and inflate, the pneumatic telescopic rod 1302 moves up and down to drive the semicircular polishing piece 1312 to move up and down, the semicircular polishing piece 1312 drives the piston pin of the clamping to move up and down, the polishing layers of the two first electromagnets 1307 polish the inner side surface of the piston pin in the circumferential direction while the semicircular polishing piece 1312 drives the piston pin of the clamping to move up and down, thereby the outer surface of the piston pin is polished at multiple angles in the circumferential direction and the radial direction, the inner side surface of the piston pin polished out is smoother and more circular, the polishing time and cost are saved simultaneously, and the polishing efficiency and the polishing quality of products are effectively improved.
Through two first electro-magnets 1307, a spring, pneumatic telescopic link 1302, semi-circular polishing piece 1312 etc. between mutually supporting, not only make this device realize polishing the piston pin surface, can also polish piston pin inboard surface, still carry out surface or inboard surface to the piston pin and carry out the multi-angle of circumference and radial direction simultaneously and polish, the piston pin that makes the mill out is more smooth and more round, time and the cost of polishing have been practiced thrift simultaneously, the efficiency and the quality of polishing of product have effectively been improved.
Example 2:
in example 1, the inventor found that the hair of the worker is easily caught between the driving gear 4 and the driven gear 1303 above the first support plate 2, and the worker is injured, and thus the inventor modified the following from example 1.
Referring to fig. 5, fig. 6 shows, the outside of first backup pad 2 is provided with protection casing 8, protection casing 8 is the tubular structure who suits with first backup pad 2, the top of protection casing 8 is open structure and the bottom sets up the opening that suits with branch 10, the three fastener 5 of inside fixedly connected with of protection casing 8, set up the draw-in groove 6 that suits with fastener 5 on the outer wall of first backup pad 2, three draw-in groove 6 is circular array distribution and array center is located the epaxial in of first backup pad 2, protection casing 8 passes through the cooperation sliding connection of draw-in groove 6 with fastener 5 with first backup pad 2, pneumatic flexible subassembly and base 1 fixed connection are passed through to fastener 5 bottom, pneumatic flexible subassembly and gas holder intercommunication, the section of thick bamboo wall of protection casing 8 is provided with transparent material's observation window 7. The protective cover 8 can avoid clamping workers in the machining process, the machining safety is improved, and the machining process is conveniently observed through the observation window 17.
When using, place the piston pin on mount pad 22 after, through the extension of the pneumatic flexible subassembly of control, the pneumatic flexible subassembly promotes protection casing 8 and upwards slides, makes protection casing 8 cover the motion piece between first backup pad 2 and the second backup pad 11, observes the course of working through observation window 17 to avoid pressing from both sides the wounded staff, improve the security of processing.
Example 3:
because the inner diameter of the existing part of the piston pin has a chamfer, the chamfer of the piston pin cannot be ground according to the method of the embodiment 1, and the piston pin needs to be ground by additional manual grinding or by using special grinding equipment alone, so that the occupied workshop space is caused, and the equipment investment is large, so the inventor further improves the method on the basis of the embodiment 1 as follows.
Referring to fig. 7-9, the sliding assembly 1306 comprises two vertical plates, a "T" -shaped cross beam is arranged between the two vertical plates, two sides of the "T" -shaped cross beam are rotatably connected with the two vertical plates, the bottom end of the lower leg of the "T" -shaped cross beam is fixedly connected with the first electromagnet 1307, and the side surface of the lower leg of the "T" -shaped cross beam is connected with a spacer 1305 through a spring.
One end of a spring on the left side of a spacer 1305 is connected with the side face of a lower support of the T-shaped cross beam, the other end of the spring on the left side of the spacer 1305 is connected with a second electromagnet 1313, the second electromagnet 1313 is fixedly connected with the spacer 1305, one end of a spring on the right side of the spacer 1305 is connected with the side face of the lower support of the T-shaped cross beam, the other end of the spring on the right side of the spacer 1305 is connected with a third electromagnet 1314, the third electromagnet 1314 is fixedly connected with the spacer 1305, and the heights of the bottom ends of the second electromagnet 1313 and the third electromagnet 1314 are lower than the height of the top end of the first electromagnet 1307.
When in use, after the inner side surface of the piston pin is polished, when the chamfer at the top end of the inner hole of the piston pin needs to be polished, the control module controls the air input of the pneumatic connecting rod 1311, the pneumatic connecting rod 1311 contracts and drives the two semicircular polishing sheets 1312 to move in the direction away from the piston pin,
then the control module controls the magnetism of the two first electromagnets 1307 to generate magnetic repulsion force between the two first electromagnets 1307, the sliding assembly 1306 moves towards the direction far away from the separation piece 1306 under the combined action of the magnetic repulsion force and the spring elasticity, and because the two first electromagnets 1307 are both magnetic, the two first electromagnets 1307 and the inner hole wall of the piston pin form fixed connection, the control module controls the air inflow of the pneumatic telescopic rod 1302 to enable the pneumatic telescopic rod 1302 to drive the upper end surface of the semicircular grinding piece 1312 to be flush with the upper end surface of the piston pin, the control module controls the air inflow of the pneumatic connecting rod 1311 to shrink and drive the two semicircular grinding pieces 1312 to move towards the direction of the piston pin, so that the semicircular grinding pieces 1312 clamp the piston pin, when the pressure value of the pressure sensor is greater than zero, then the control module controls the magnetism of the two first electromagnets 1307 to enable the magnetic force to disappear between the two first electromagnets 1307, continuously adjusting the pneumatic telescopic rod 1302 to enable the upper end surface of the piston pin to be flush with the bottom end surfaces of the two first electromagnets 1307, then enabling the control module to control the magnetism of the two first electromagnets 1307 to generate magnetic attraction between the two first electromagnets 1307, simultaneously enabling the first electromagnet 1307 and the second electromagnet 1313 on the left side of the partition 1305 to generate magnetic repulsion, enabling the first electromagnet 1307 on the right side of the partition 1305 and the third electromagnet 1314 to generate magnetic repulsion, under the action of the magnetic repulsion and the spring elasticity, enabling the T-shaped cross beams on the two sides of the partition 1305 to move towards the two sides, enabling the top ends to be far away by the repulsion due to the magnetic attraction generated at the bottom ends of the two first electromagnets 1307, thereby forming the shape as shown in the figure, then enabling the semicircular polishing piece 1312 and the clamped piston pin to move upwards by controlling the air inflow of the pneumatic telescopic rod 1302 to enable the chamfer at the upper end of the piston pin to be in contact with the polishing part of the first electromagnet 1307, under the rotation that servo motor 12 drove first electro-magnet 1307, make the portion of polishing of first electro-magnet 1307 and piston pin relative motion to the realization is to the polishing of piston pin upper end chamfer. Through mutually supporting between first electro-magnet 1307, second electro-magnet 1313, third electro-magnet 1314 and the spring etc. under, can polish to the piston pin surface simultaneously, the piston pin inner bore wall is polished to the second aspect, the third aspect is realized polishing the chamfer of piston pin inner ring, has solved the problem that needs artifical polishing separately or the dedicated equipment of polishing of exclusive use polishes the chamfer of piston pin inner ring and carries out polishing, has reduced occupation space, has reduced equipment investment cost.
A blanking assembly 14 is further arranged on the peripheral side surface of the mounting seat 1308, the blanking assembly 14 comprises a blanking plate, the blanking plate is located in a gap between the two semicircular polishing pieces 1312 and corresponds to the gap, an output shaft of the servo motor 12 is provided with a slot, and an electromagnetic bolt which is in inserting fit with the slot is arranged on the inner peripheral side surface of the second supporting plate 11.
When a polished piston pin needs to be taken out from the middle of the semicircular polishing piece 1312, the magnetism of the two first electromagnets 1307 is controlled, the magnetism of the two first electromagnets 1307 disappears, the control module controls the air inflow of the pneumatic telescopic rod 1302 to enable the semicircular polishing piece 1312 and the blanking assembly 4 to move downwards together, the two first electromagnets 1307 are moved out from the inner side surface of the piston pin, meanwhile, the control module controls the air inflow of the pneumatic connecting rod 1311 to contract and drive the two semicircular polishing pieces 1312 to move away from the piston pin, a gap is formed between the two semicircular polishing pieces 1312, the control electromagnetic bolt is inserted into a slot of an output shaft of the servo motor 12, the servo motor 12 drives the second supporting plate 11 to rotate around a central axis of an output shaft of the servo motor 12 through the electromagnetic bolt, the second supporting plate 11 rotates and drives the first electromagnets 1307 to synchronously rotate around the central axis of the output shaft of the servo motor 12, first electromagnet 1307
Move into to one side of piston pin from the piston pin top, through the air input of control pneumatic telescopic link 1302, make semi-circular piece 1312 of polishing and unloading subassembly 4 move to first electro-magnet 1307 bottom height and be less than the top height of piston pin with last, servo motor 12 reverses, second backup pad 11 rotates and drives first electro-magnet 1307 around servo motor 12 output shaft's axis synchronous rotation, make first electro-magnet 1307 promote the piston pin and get into the unloading board top of unloading subassembly 14 from the middle space of two semi-circular pieces 1312 of polishing to accomplish the unloading.
To sum up, the basic polishing function of this polishing device can not only be realized to the cooperation between each part and structure, still promoted this polishing device's practicality simultaneously through the improvement in aspects such as the stability of device self and course of working, the convenience of work piece loading and unloading, the compactness of device self structure.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (8)
1. The utility model provides a piston pin grinding device for machining, includes base (1), its characterized in that: an air compressor (9) is fixedly connected right above the base (1), an exhaust pipeline of the air compressor (9) is communicated with an air storage tank, a first supporting plate (2) is arranged right above the base (1), the base (1) is fixedly connected with the first supporting plate (2) through a supporting rod (10), a second supporting plate (11) is arranged right above the first supporting plate (2), the first supporting plate (2) is connected with the second supporting plate (11) through a transmission rod (3), and a plurality of polishing assemblies (13) which are distributed in an annular array mode by taking a middle shaft of the transmission rod (3) as a center are arranged between the first supporting plate (2) and the second supporting plate (11); the peripheral side surface of the transmission rod (3) is provided with a driving gear (4); the top end of the second supporting plate (11) is fixedly connected with a servo motor (12) through a bolt, and an output shaft of the servo motor (12) penetrates through the second supporting plate (11) to be in transmission connection with the transmission rod (3) and is in rotary connection with the second supporting plate (11) at the penetrating position;
the grinding assembly (13) comprises a first connecting rod (1301) and a pneumatic telescopic rod (1302), the first connecting rod (1301) is rotatably connected with a second supporting plate (11), a driven gear (1303) is arranged on the peripheral side of the first connecting rod (1301), a sliding groove (1304) is formed in the bottom end of the first connecting rod (1301), a spacer (1305) is arranged in the middle of the sliding groove (1304), sliding assemblies (1306) are arranged on two sides of the spacer (1305) and are connected with the spacer (1305) through springs, and first electromagnets (1307) are arranged at the bottoms of the sliding assemblies (1306); a polishing layer is arranged on the peripheral side surface of the first electromagnet (1307);
the pneumatic telescopic rod (1302) is fixedly connected with a first supporting plate (2), the pneumatic telescopic rod (1302) is superposed with a center shaft of a first connecting rod (1301), a mounting seat (1308) is fixedly mounted at the top end of the pneumatic telescopic rod (1302), two fixing plates (1309) are fixedly connected to the top of the mounting seat (1308), the two fixing plates (1309) are symmetrically distributed, the two fixing plates (1309) are connected with a semicircular polishing piece (1312) through a pneumatic connecting rod (1311), the pneumatic connecting rod (1311) is connected with the semicircular polishing piece (1312), the pneumatic connecting rod (1311) and the pneumatic telescopic rod (1302) are communicated with an air storage tank through an air vent pipeline, and a pressure sensor is arranged between the semicircular polishing piece (1312) and the pneumatic connecting rod (1311).
2. The piston pin grinding device for machining according to claim 1, characterized in that: a protective cover (8) is arranged on the outer side of the first supporting plate (2), the protective cover (8) is of a cylindrical structure matched with the first supporting plate (2), the top of the protective cover (8) is of an open structure, the bottom of the protective cover is provided with an opening which is matched with the supporting rod (10), the interior of the protective cover (8) is fixedly connected with three clamping pieces (5), the outer wall of the first supporting plate (2) is provided with clamping grooves (6) matched with the clamping pieces (5), the three clamping grooves (6) are distributed in a circular array, the center of the array is positioned on the central shaft of the first supporting plate (2), the protective cover (8) and the first supporting plate (2) are in sliding connection with the clamping piece (5) through the matching of the clamping groove (6), the bottom end of the clamping piece (5) is fixedly connected with the base (1) through the pneumatic telescopic component, the wall of the protective cover (8) is provided with an observation window (7) made of transparent material.
3. The piston pin grinding device for machining according to claim 1, characterized in that: the mounting base (1308) is provided with a vent hole (1310); the vent hole (1310) is communicated with a filter chamber through an air passage, and the filter chamber is communicated with an air inlet pipeline of an air compressor (9).
4. The piston pin grinding device for machining according to claim 1, characterized in that: the polishing device is characterized in that a polishing layer is arranged on the upper end surface of the mounting seat (1308), and the polishing layer on the mounting seat (1308) is connected with the upper end surface of the mounting seat (1308) through a sticky buckle.
5. The piston pin grinding device for machining according to claim 1, characterized in that: the filter chamber is including retrieving the box, retrieve box movable mounting on the filter chamber top, the bottom plate of retrieving the box is electromagnetic filter, it is located filter chamber air inlet department to retrieve the box, it is equipped with the active carbon to retrieve the box bottom.
6. The piston pin grinding device for machining according to claim 1, characterized in that: the sliding assembly (1306) comprises two vertical plates, a T-shaped cross beam is arranged between the two vertical plates, two sides of the T-shaped cross beam are rotatably connected with the two vertical plates, the bottom end of a lower supporting leg of the T-shaped cross beam is fixedly connected with a first electromagnet (1307), and the side face of the lower supporting leg of the T-shaped cross beam is connected with a spacer (1305) through a spring.
7. The piston pin grinding device for machining according to claim 6, characterized in that: one end of a left spring of the spacer (1305) is connected with the lower leg side of the T-shaped cross beam, the other end of the left spring of the spacer (1305) is connected with a second electromagnet (1313), the second electromagnet (1313) is fixedly connected with the spacer (1305), one end of a right spring of the spacer (1305) is connected with the lower leg side of the T-shaped cross beam, the other end of the right spring of the spacer (1305) is connected with a third electromagnet (1314), the third electromagnet (1314) is fixedly connected with the spacer (1305), and the bottom heights of the second electromagnet (1313) and the third electromagnet (1314) are lower than the top height of the first electromagnet (1307).
8. The piston pin grinding device for machining according to claim 1, characterized in that: the periphery side face of the mounting seat (1308) is further provided with a blanking assembly (14), the blanking assembly (14) comprises a blanking plate, the blanking plate is located in a gap between the two semicircular polishing plates (1312) and corresponds to the gap, an output shaft of the servo motor (12) is provided with a slot, and the periphery side face of the inner periphery of the second supporting plate (11) is provided with an electromagnetic bolt matched with the slot in an inserting mode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110577361.2A CN113211200A (en) | 2021-05-26 | 2021-05-26 | Piston pin grinding device for machining |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110577361.2A CN113211200A (en) | 2021-05-26 | 2021-05-26 | Piston pin grinding device for machining |
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| Publication Number | Publication Date |
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| CN113211200A true CN113211200A (en) | 2021-08-06 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202110577361.2A Withdrawn CN113211200A (en) | 2021-05-26 | 2021-05-26 | Piston pin grinding device for machining |
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| CN (1) | CN113211200A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114986301A (en) * | 2022-07-07 | 2022-09-02 | 含山县大力精密机械有限公司 | Pump body finish machining isolated plant convenient to operation |
| CN115139174A (en) * | 2022-07-18 | 2022-10-04 | 安徽誉林汽车部件有限公司 | Automatic chamfering device and chamfering method for automobile bushing |
| CN116572120A (en) * | 2023-07-12 | 2023-08-11 | 晋宁腾锐光学仪器工贸有限公司 | Automatic centre gripping formula optical glass grinding device |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06190655A (en) * | 1992-12-25 | 1994-07-12 | Honda Motor Co Ltd | Positioning device for pressing-in of piston pin |
| CN108515461A (en) * | 2018-03-30 | 2018-09-11 | 宁波高新区新柯保汽车科技有限公司 | Auto parts and components processing unit (plant) |
| CN109108772A (en) * | 2018-08-20 | 2019-01-01 | 刘诗晨 | A kind of small portable machining turning polishing all-in-one machine |
| CN109333182A (en) * | 2018-11-29 | 2019-02-15 | 黄石市科兴机电科技有限公司 | A kind of machining piston pin grinding device |
| CN112276755A (en) * | 2020-11-20 | 2021-01-29 | 江苏春兰机械制造有限公司 | Piston pin grinding device for machining |
| CN112571184A (en) * | 2020-12-04 | 2021-03-30 | 容林 | New energy automobile makes and uses grinding device |
-
2021
- 2021-05-26 CN CN202110577361.2A patent/CN113211200A/en not_active Withdrawn
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06190655A (en) * | 1992-12-25 | 1994-07-12 | Honda Motor Co Ltd | Positioning device for pressing-in of piston pin |
| CN108515461A (en) * | 2018-03-30 | 2018-09-11 | 宁波高新区新柯保汽车科技有限公司 | Auto parts and components processing unit (plant) |
| CN109108772A (en) * | 2018-08-20 | 2019-01-01 | 刘诗晨 | A kind of small portable machining turning polishing all-in-one machine |
| CN109333182A (en) * | 2018-11-29 | 2019-02-15 | 黄石市科兴机电科技有限公司 | A kind of machining piston pin grinding device |
| CN112276755A (en) * | 2020-11-20 | 2021-01-29 | 江苏春兰机械制造有限公司 | Piston pin grinding device for machining |
| CN112571184A (en) * | 2020-12-04 | 2021-03-30 | 容林 | New energy automobile makes and uses grinding device |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114986301A (en) * | 2022-07-07 | 2022-09-02 | 含山县大力精密机械有限公司 | Pump body finish machining isolated plant convenient to operation |
| CN115139174A (en) * | 2022-07-18 | 2022-10-04 | 安徽誉林汽车部件有限公司 | Automatic chamfering device and chamfering method for automobile bushing |
| CN116572120A (en) * | 2023-07-12 | 2023-08-11 | 晋宁腾锐光学仪器工贸有限公司 | Automatic centre gripping formula optical glass grinding device |
| CN116572120B (en) * | 2023-07-12 | 2023-09-15 | 晋宁腾锐光学仪器工贸有限公司 | Automatic centre gripping formula optical glass grinding device |
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Application publication date: 20210806 |