CN212527176U

CN212527176U - Quasi-planetary low-speed high-precision ball valve core grinding machine tool

Info

Publication number: CN212527176U
Application number: CN202021817097.2U
Authority: CN
Inventors: 伍若峰
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-08-27
Filing date: 2020-08-27
Publication date: 2021-02-12
Anticipated expiration: 2030-08-27

Abstract

The utility model discloses a planetary-like grinding machine tool for a low-speed high-precision ball valve core, which consists of a workpiece clamping system, a chuck system, a feed system and a machine tool bottom plate, wherein both a workpiece in the workpiece clamping system and a main shaft in the chuck system rotate at low speed; the grinding part in the chuck system adopts a miniature pneumatic or electric motor to drive a grinding wheel or a felt wheel to grind. The linear velocity of the cutting part of the utility model exceeds the linear velocity of the traditional chuck, so that the grinding efficiency and the grinding precision both exceed the conventional processing method; the grinding feed adopts the main shaft to carry out straight feed, the clearance between the main shaft and the bearing bush is small, the feed stroke is short, and the machining error caused in the feed process of the grinding tool is avoided; during grinding, the workpiece and the grinding tool are in an externally tangent relation, scraps are easy to remove, and the working part of the grinding tool is easy to trim and clean; the utility model has no limit to the size of the processed object and has wide adjusting range; compared with the traditional machine tool, the utility model discloses simple structure, manufacturing cost is lower.

Description

Quasi-planetary low-speed high-precision ball valve core grinding machine tool

Technical Field

The utility model belongs to the technical field of mechanical design makes the specialty, a ball valve case grinding lathe is related to, and its usage is the spherical case that is arranged in processing all kinds of ball valves.

Background

The valve is a control component in a fluid conveying system, has the functions of stopping, regulating, guiding, preventing counter flow, stabilizing pressure, shunting or overflowing and relieving pressure and the like, and is a device for controlling the direction, pressure and flow of fluid in the fluid system. Ball valves play an important role in a wide variety of valves, and the operating principle of the ball valves is to rotate a valve core to open or close the valve. The ball valve switch is light, small in size, reliable in sealing, simple in structure and convenient to maintain, can be made into a large-caliber ball valve, a sealing surface and a spherical surface are always in a closed state, and are not easily eroded by a medium, so that the ball valve switch is widely applied to various industries. The valve core of the ball valve is a round ball with an opening, the valve core is a key part of the ball valve and is also a part which is directly contacted with a medium and is used for controlling the cutting and the communicating of a pipeline, and the quality of the valve core directly determines the quality of the performance of the valve. Therefore, the valve core has extremely high requirements on geometric dimension precision, surface hardness and roughness, and the design and use requirements can not be met through processes such as precision grinding until grinding and polishing.

As shown in fig. 1, the conventional spool grinding process is such that: the roughly machined valve core workpiece rotates at a low speed on the clamping device, and a chuck which is clamped with a plurality of grinding tools (generally consisting of high-performance oilstones) rotates at a high speed around the workpiece, and the centers of the two are equal in height and form a ninety-degree angle with each other. During clamping, the rotation center of the chuck is aligned with the center of the valve core, and during working, the chuck approaches to the center of a workpiece along the axial direction until the chuck contacts the workpiece to start feed grinding. The rotation of the workpiece itself and the revolution of the grinding tool cause the locus of their points of contact to form a sphere. Therefore, the stability of chuck rotation and feed is the key to ensure the processing quality of the workpiece while maintaining the stable rotation of the workpiece. However, in order to achieve the required surface roughness, the chuck must be rotated at a high speed, and the chuck is difficult to achieve an ideal state due to dynamic balance during high-speed rotation, which causes vibration, thereby making it difficult to ensure the machining quality. In order to eliminate such vibrations as much as possible, it is necessary to increase the size and mass of the grinding machine and to increase the manufacturing accuracy and structural complexity of the machine, which results in an increase in the manufacturing costs and an increase in the price of such machines. Therefore, the above-mentioned processing technique has the first problem that: not only is the product quality of the valve difficult to ensure, but also the manufacturing cost of the valve is improved. The second problem is: for valve cores with different sizes, grinding machine tools with different sizes and specifications are required. On the same machine tool, the same chuck can only grind workpieces with similar sizes, and the adjustment range is limited. Therefore, each machine tool needs to be provided with a series of chucks, the chucks need to be replaced according to the size of a workpiece during machining, relevant parameters need to be readjusted, operation is quite troublesome, and working efficiency is reduced. For valve manufacturers, more machine tools and accessories are purchased, increasing capital cost. The third problem is: according to the grinding method, the workpiece and the grinding tool are cut in an inner cutting mode, scraps generated in the machining process are not easy to remove and are easy to accumulate on the surface of the grinding tool, so that the cutting function of the grinding tool is reduced, and the working efficiency is reduced. And the grinding tool needs to be cleaned in time in the processing process so as to ensure the normal processing. The fourth problem is: because the feed of the chuck is pushed by the dovetail guide rail, certain working errors can be generated due to the objective existence of the gap between the guide rails, and the quality of products is influenced.

SUMMERY OF THE UTILITY MODEL

In order to overcome the above-mentioned problem that current case grinding process and equipment exist, the utility model aims at designing a kind of planetary type low-speed high accuracy valve core grinding machine tool of brand-new structure.

The utility model adopts the technical scheme as follows: the utility model provides a kind of planetary low-speed high accuracy ball valve case grinding machine, its characterized in that: the machine tool comprises a workpiece clamping system, a chuck system, a feed system and a machine tool bottom plate, wherein both a workpiece in the workpiece clamping system and a main shaft in the chuck system rotate at a low speed, and the low-speed rotation is rotation of dozens of revolutions per minute; the grinding part in the chuck system adopts a miniature pneumatic or electric motor with the rotating speed of tens of thousands of revolutions per minute to drive a grinding wheel or a felt wheel to grind.

The chuck system comprises a pneumatic motor, a fixed bottom plate, a main shaft and a chuck, wherein the chuck is locked at the front end of the main shaft by a compression screw, the compression screw is loosened, and the chuck can slide back and forth on the main shaft, so that the large-scale adjustment between a workpiece and a grinding tool is facilitated; the pneumatic motor is connected with the chuck through a fixed bottom plate, and the fixed bottom plate can translate on the chuck and also can rotate to a certain degree so as to adjust the working posture of the pneumatic motor; the tail end of the main shaft is connected with a low-speed motor through a sliding spline combination.

The rear end of the main shaft is provided with a compressed air leading-in ring with a sealing ring, the main shaft is provided with an inner cavity from the rear end of the main shaft to the front end of the main shaft, the inner cavity is connected with a soft air pipe at the front end of the main shaft, and the other end of the soft air pipe is connected with the pneumatic motor.

The feed system comprises a feed cone disc, a trapezoidal screw, a moving screw sleeve, a main rocker arm shaft, a feed push rod, a rolling wheel, a tool withdrawal rocker arm, a balance rod, a tension spring, a feed platform support and the like, wherein the feed cone disc is fixed on the main shaft; when the tool is withdrawn, the hand wheel is operated to reversely rotate the trapezoidal screw, so that the tool feeding push rod and the rolling wheel are withdrawn, and at the moment, under the action of the extension spring, the tool withdrawing conical disc and the main shaft move backwards together under the action of the tool withdrawing rocker arm and the balance rod, so that the tool withdrawal is realized.

The grinding feed of the feed system is realized by pushing a pneumatic motor to move forwards by the axial movement of a main shaft, the pneumatic motor is adjusted to a set position through a fixed bottom plate before grinding, and the large-size adjustment of a grinding tool is realized by loosening a compression screw and pushing a chuck to slide on the main shaft.

The workpiece clamping system, the chuck system and the feed system are all installed on the machine tool bottom plate.

Compare with traditional case grinding process, the utility model has the following advantages: 1. the main shafts in the workpiece clamping system and the chuck system both adopt a low-speed rotating mode, so that the vibration of the chuck caused by unbalance of dynamic balance is avoided; the grinding part adopts a miniature pneumatic or electric motor to drive a grinding wheel or a felt wheel to cut, the rotating speed of the motor is extremely high and can reach tens of thousands of revolutions per minute, so the linear speed of the cutting part is higher than that of the traditional chuck, and the grinding efficiency and the grinding precision exceed those of the conventional processing method. 2. The grinding feed adopts the main shaft to directly feed without a guide rail, the rotating speed of the main shaft is very low, the gap between the main shaft and a bearing bush is very small, the large-amplitude stroke adjustment of the main shaft is completed by a grinding tool fixing chuck, and the feed stroke of the main shaft is very short, so that the machining error caused in the feed process of the grinding tool is avoided. 3. The utility model discloses the limitation problem of the size of general like machine tool machining object has basically been solved. The valve cores with different sizes can be processed on the same machine tool, and the size range is very wide. The adjustment of the processing parameters is also very simple. Theoretically, if the machine tool is designed according to the valve core with the largest size, only one machine tool is needed to machine various valve cores from the smallest to the largest. When the valve core with smaller size is processed, the head part of the main shaft is extended by a method of additionally installing an extension rod, and the chuck of the grinding tool is pushed forward to a proper position. Each machine tool can greatly expand the processing range only by being provided with a certain number of extension bars, and the extension bars are connected with the taper sleeves by Morse taper heads, so that the machine tool is convenient and quick and is reliable in connection. 4. The utility model discloses a work piece is circumscribed relation with the grinding apparatus during grinding, and the bits end is got rid of easily, and grinding apparatus work position also easily is maintained and is cleared up. 5. Compared with the traditional machine tool, the utility model discloses simple structure, manufacturing cost is lower.

Drawings

FIG. 1 is a schematic diagram of grinding machining of a valve core of a current ball valve;

FIG. 2 is a schematic structural view of the present invention;

FIG. 3 is a top view of FIG. 2 with the workpiece clamping system in place;

fig. 4 is a schematic view of the extension of the spindle of the present invention;

in fig. 1: i is a grinding tool, II is a chuck, III is a valve core workpiece to be processed, and IV is a clamping shaft of the valve core workpiece to be processed;

in fig. 2-4, 1 is the valve core to be processed: 2 is a machine tool bottom plate; 3 is a grinding wheel or a felt wheel; 4 is a pneumatic motor; 5 is a fixed pressure plate; 6 is a fixed base plate; 7 is a compression screw; 8 is a chuck; 9 is a soft trachea; 10 is a main shaft; 11 is a feed cone disc; 12 is a feed platform; 13 is a feed platform support; 14 a main shaft bearing support; 15 is a compressed air introduction ring; 16 is a low speed motor; 17 is a motor mounting support; 18 is a valve core processing clamp; 19 is a headstock support; 20 is a chuck; 21 is a chicken heart clip; 22 is a pulley; 23 is a low speed motor; 24 is an extension spring; 25 is a retracting rocker arm; 26 is a retracting rocker shaft; 27 is a balance bar; 28 is a feed pusher bar; 29 is a feed roller; 30 is a main rocker shaft; 31 is a main rocker arm; 32 is a movable screw sleeve; 33 is a trapezoidal screw; 34 is a seal ring; 35 is a sliding spline combination; 36 is a baffle; 37 is a tension screw; 38 is an extension bar; and 39 is a morse taper sleeve.

Detailed Description

The following description of the embodiments will be made with reference to the accompanying drawings.

2-4, the utility model relates to a kind of planetary type low-speed high accuracy ball valve case grinding machine tool, by work piece clamping system, chuck system, feed system and lathe bottom plate composition, work piece clamping system and chuck system all adopt the low-speed rotation, are used for reducing the vibration that dynamic balance unbalance arouses the chuck, the low-speed rotation is the rotational speed of tens revolutions per minute; the grinding part in the chuck system adopts a miniature pneumatic motor or an electric motor with the rotating speed of tens of thousands of revolutions per minute to drive a grinding wheel or a felt wheel to grind, thereby ensuring that the working linear speed of a cutting part is higher than that of the traditional grinding, and ensuring that the processed part has high-quality surface roughness. The concrete structure is as follows:

(1) a workpiece clamping system: the workpiece is clamped by a valve core processing clamp 18 and supported by two apexes of a bed head and a bed tail, and the large workpiece needs to be supported by an auxiliary support; in addition, the low-speed motor 23 drives the workpiece 1 to rotate at a low speed through the belt pulley 22 and the heart clamp 21.

(2) A chuck system: the pneumatic clamping device comprises a pneumatic motor 4, a fixed bottom plate 6, a main shaft 10 and a chuck 8, wherein the chuck 8 locked by a compression screw 7 is installed at the front end of the main shaft 10. The chuck 8 can slide back and forth on the spindle 10 by loosening the compression screw. The air motor 4 is fixed on the fixed base plate 6 through the fixed pressing plate 5. The fixed bottom plate 6 is connected with the chuck 8, and the fixed bottom plate 6 can move horizontally on the chuck 8 and also can rotate to a certain degree so as to adjust the working posture of the pneumatic motor. The rear end of the main shaft 10 is provided with a compressed air introduction ring 15 having a packing 32 to prevent air leakage. The main shaft 10 is provided with an inner cavity from the rear end of the main shaft to the front end of the main shaft, the inner cavity is connected with a soft air pipe at the front end of the main shaft, the other end of the soft air pipe is connected with the pneumatic motor, and compressed air is led to the front end of the main shaft from the inner cavity of the main shaft and shunted to the soft air pipe to drive the pneumatic motor to work. The tail end of the main shaft is connected with the low-speed motor 16 through a sliding spline combination 35. The motor 16 is fixed on the machine tool bottom plate 2 through a motor support 17. The motor 16 drives the main shaft 10 to rotate at a low speed through the sliding spline assembly 35, and the main shaft can move back and forth relative to the motor within a small range.

(3) A feed system: the system comprises a feed cone disc 11, a trapezoidal screw 33, a movable screw sleeve 32, a main rocker arm 31, a main rocker arm shaft 30, a feed push rod 28, a roller 29, a tool withdrawal rocker arm 25, a balance rod 27, an extension spring 24, a feed platform 12, a feed platform support 13 and the like. The feed cone disk 11 is fixed on the main shaft 10. During feeding, the control hand wheel rotates the trapezoidal screw 33 to drive the movable screw sleeve 32 to move backwards, the main rocker arm 31 rotates backwards and forwards, the feeding push rod 28 and the roller 29 move forwards, and the roller and the cone act to generate axial displacement of the main shaft 10 to realize axial feeding. When the tool is withdrawn, the hand wheel is operated to reversely rotate the trapezoidal screw 33, so that the tool feeding push rod 28 and the rolling wheel 29 are withdrawn, and at the moment, under the action of the tension spring 24, the tool withdrawing rocker arm 25 and the balance rod 27 act to enable the tool feeding conical disc 11 and the main shaft 10 to move backwards together, so that the tool withdrawal is realized. It should be noted that the functional description of the feed system is a working process in the case where the position of the grinder and the position of the workpiece are adjusted to be very close, and the working stroke is relatively small for grinding. The large advance and retreat of the grinding tool is realized by loosening the compression screw 7 and then pushing the chuck 8 to slide on the main shaft.

(4) A machine tool bottom plate: it is a common platform on which the systems are mounted. The main shaft 10 is mounted on the platform by two bearings 14 using semi-circular bearing bushes, and a small clearance and sufficient lubrication between the shaft and the bearing bushes should be maintained. As long as platform itself has sufficient high flatness and rigidity, just can guarantee the mutual position precision between each system relatively easily to reach the operating condition that makes each portion of lathe can the even running, thereby make the utility model discloses an each item target can be realized.

Work piece clamping system the chuck system with the feed system is all installed on the lathe bottom plate.

In order to improve the working efficiency, the chuck of the utility model can be designed into a plurality of parts, such as 2-4 parts, so that a plurality of spherical valve cores can be processed at one time.

The feed system of the utility model can be pushed by a shifting fork or driven by a numerical control device; the pneumatic motor may be replaced by an electric motor, etc.

The embodiments of the present invention are only descriptions of the simplified embodiments of the present invention, and are not intended to limit the spirit and scope of the present invention. Therefore, without departing from the design concept of the present invention, the technical content of the present invention, which is claimed by the present invention, is fully recorded in the claims.

Claims

1. The utility model provides a kind of planetary low-speed high accuracy ball valve case grinding machine, its characterized in that: the machine tool comprises a workpiece clamping system, a chuck system, a feed system and a machine tool bottom plate, wherein both a workpiece in the workpiece clamping system and a main shaft in the chuck system rotate at low speed, and the low-speed rotation is rotation of dozens of revolutions per minute; the grinding part in the chuck system adopts a miniature pneumatic or electric motor with the rotating speed of tens of thousands of revolutions per minute to drive a grinding wheel or a felt wheel to grind.

2. The quasi-planetary low-speed high-precision ball valve core grinding machine tool according to claim 1, characterized in that: the chuck system comprises a pneumatic motor, a fixed bottom plate, a main shaft (10) and a chuck (8), wherein the chuck (8) is locked at the front end of the main shaft (10) through a compression screw (7), the compression screw is loosened, and the chuck (8) can slide back and forth on the main shaft (10) so as to be convenient for large-scale adjustment between a workpiece and a grinding tool; the pneumatic motor (4) is connected with the chuck (8) through the fixed bottom plate (6), and the fixed bottom plate (6) can translate and rotate on the chuck (8) so as to adjust the working posture of the pneumatic motor; the tail end of the main shaft is connected with a low-speed motor (16) through a sliding spline combination (35).

3. The quasi-planetary low-speed high-precision ball valve core grinding machine tool according to claim 2, characterized in that: the rear end of the main shaft is provided with a compressed air leading-in ring (15) with a sealing ring, the main shaft is provided with an inner cavity from the rear end of the main shaft to the front end of the main shaft, the inner cavity is connected with a soft air pipe at the front end of the main shaft, and the other end of the soft air pipe is connected with a pneumatic motor.

4. The quasi-planetary low-speed high-precision ball valve core grinding machine tool according to claim 1, characterized in that: the feed system consists of a feed cone disc (11), a trapezoidal screw (33), a movable screw sleeve (32), a main rocker arm (31), a main rocker arm shaft (30), a feed push rod (28), a roller (29), a tool withdrawal rocker arm (25), a balance rod (27), a tension spring (24), a feed platform (12), a feed platform support (13) and a control hand wheel, wherein the feed cone disc (11) is fixed on the main shaft (10), during feed, the control hand wheel rotates the trapezoidal screw (33) to drive the movable screw sleeve (32) to move backwards, the main rocker arm (31) rotates backwards to enable the feed push rod (28) and the roller (29) to move forwards, and the roller and a conical surface act to enable the main shaft (10) to generate axial displacement to realize axial feed; when the tool is withdrawn, the hand wheel is operated to reversely rotate the trapezoidal screw (33), so that the tool feeding push rod (28) and the rolling wheel (29) are withdrawn, and at the moment, under the action of the tension spring (24), the tool withdrawing rocker (25) and the balance rod (27) act to enable the tool feeding conical disc (11) and the main shaft (10) to move backwards together to realize tool withdrawal.

5. The quasi-planetary low-speed high-precision ball valve core grinding machine tool according to claim 4, characterized in that: the grinding feed of the feed system is realized by pushing a pneumatic motor to move forwards by the axial movement of a main shaft (10), the pneumatic motor is adjusted to a set position through a fixed bottom plate before grinding, and the adjustment of a grinding tool is realized by loosening a compression screw (7) and then pushing a chuck (8) to slide on the main shaft.

6. The quasi-planetary low-speed high-precision ball valve core grinding machine tool according to claim 1, characterized in that: the workpiece clamping system, the chuck system and the feed system are all installed on the machine tool bottom plate.

7. The quasi-planetary low-speed high-precision ball valve core grinding machine tool according to claim 1, characterized in that: the chuck is 1 or more pieces.

8. The quasi-planetary low-speed high-precision ball valve core grinding machine tool according to claim 7, characterized in that: the plurality of pieces is 2, 3 or 4 pieces.