CN105952636B - The capacity new-type double screw pump of self-lubricating supporting - Google Patents

Abstract

A self-lubricating support variable volume new twin-screw pump belongs to the technical field of screw pumps. The left pump housing is provided with a medium input end, and the right pump housing is provided with a medium output end. The connection between the left pump housing and the right pump housing There is a self-lubricating bearing device inside, a driving screw and a driven screw with variable pitch run through the pump body, a rear support cover is connected to the end of the left pump casing, and a driving gear and a driven gear that are meshed are arranged in the rear support cover. Gear, the end face of the rear support cover is provided with a rear end cover, the end of the right pump casing is connected with a front support cover, the end face of the front support cover is provided with a front end cover, and the head of the driving screw sticks out of the front end cover as a twin-screw pump The power input end of the screw; the volume is changed by changing the fixed pitch of the screw, which can reduce the deformation of the middle part of the screw in the working process of the twin-screw pump, reduce the vibration and noise when transporting gas-liquid media, and improve the stability of the screw pump transmission. , Improve the bearing capacity of the gear, thereby improving the working efficiency of the screw pump.

Description

Self-lubricating support of variable volume new twin-screw pump

technical field

The invention belongs to the technical field of screw pumps, and relates to a novel twin-screw pump with self-lubricating support and variable volume, in particular to a novel twin-screw pump with bearing support, arc gear pump transmission and variable volume.

Background technique

The twin-screw pump is a volumetric quantitative pump. The screws in the pump mesh with each other, and the screw and the hole wall and pump body that accommodate the screw form a sealed cavity that is connected to each other. The ends of the two screw rods are connected by synchronous gear transmission, and the synchronous gear is set in the gear box with independent lubrication and separated from the pump chamber. The synchronous gear ensures the relatively continuous stationary rotation of the screw, so that the sealing chamber can move forward continuously and smoothly in the axial direction without agitation, so as to achieve the purpose of pumping. The outstanding feature of the twin-screw pump is that it has good self-priming performance, can supply liquid continuously and smoothly without pulsation, the pressure of the conveying medium is stable, the flow rate is constant, the vibration is small, and the noise is low. The above-mentioned properties of the twin-screw pump make it widely used in various fields, such as oil field, oil refining, steel, thermal power, chemical industry, etc., to transport various viscosities, especially high-viscosity liquid media.

But its disadvantages are:

1. When the conveying medium moves from the input port to the output port, the effective volume of the conveying medium in the pump cavity remains unchanged, only the position of the pump input port and the output port changes, so when there is a difference between the input port and the output port When there is a large pressure difference, especially when transporting gas, since the gas is very easy to compress, the pressure at the output port will not be too high, which will easily cause surge and greatly reduce the output efficiency of the pump.

2. Due to the current structure of the synchronous gear transmission device used in the twin-screw pump is mainly spur gears and helical gears. Although the manufacturing and assembly process of the spur gear transmission is relatively simple, it is prone to shock, vibration and noise when the gears are meshing and withdrawing, and its bearing capacity is also poor; the helical gear transmission has a large coincidence coefficient, stable transmission, high gear strength, and is suitable It is suitable for heavy load transmission and low noise, but helical gears will generate axial force, and the assembly process is more complicated than that of spur gears.

3. During the working process of the twin-screw pump, the screw will be affected by the pressure of the fluid, and the screw will be deformed, especially in the middle of the screw.

Contents of the invention

The purpose of the present invention is to address the existing technical problems, to propose a self-lubricating bearing variable volume novel twin-screw pump, to change the volume by changing the fixed pitch of the screw, so that the deformation of the middle part of the screw in the working process of the twin-screw pump can be reduced, and Reduce the vibration and noise when transporting gas-liquid media, improve the stability of the screw pump transmission, increase the bearing capacity of the gears, and thus improve the working efficiency of the screw pump.

The technical solution of the present invention is: a self-lubricating support variable volume new twin-screw pump, including a twin-screw pump housing; it is characterized in that: the twin-screw pump housing is composed of a left pump housing and a right pump housing, so The left pump casing is provided with a medium input end, the right pump casing is provided with a medium output end, and the connection between the left pump casing and the right pump casing is provided with a self-lubricating bearing device. The casing and the right pump casing are provided with a driving screw and a driven screw with variable pitch. The outer contours of the driving screw and the driven screw match the inner wall of the twin-screw pump casing, and the ends of the left pump casing are connected A rear support cover is provided, and a driving gear and a driven gear meshed with each other are arranged inside the rear support cover, the driving gear is functionally connected with the driving screw, and the driven gear is functionally connected with the driven screw, The end face of the rear support cover is provided with a rear end cover, the end of the right pump casing is connected with a front support cover, the end face of the front support cover is provided with a front end cover, and the head of the driving screw sticks out The front end cover is used as the power input end of the twin-screw pump, and the rear end cover, rear support cover, left pump casing, right pump casing, front support cover and front end cover form a closed cavity through mechanical seal.

Both the driving screw and the driven screw are single-headed screws with uniform variable pitch. .

The uniform variable pitch is the change of the pitch of the active screw and the driven screw from large to small. The initial pitch is p, the lift is d, the number of upper teeth on the screw is n, and the pitch is changed from large to small by p+nd, p+ (n-1)d, p+(n-2)d, p+(n-3)d and so on.

Both the driving gear and the driven gear are double-arc gears, the modulus and the number of teeth of the driving gear and the driven gear are equal, the driving gear is connected with the driving screw through a gear sleeve, and the gear sleeve is connected with the driving screw through a flat key.

A bushing and a locking round nut are respectively arranged in the axial direction of the driving gear and the driven gear.

The self-lubricating bearing device is located between the left pump housing and the right pump housing, and embedded in the left pump housing and the right pump housing; the self-lubricating bearing device is composed of a bearing positioning device, an active lubricating bearing arranged in the bearing positioning device It is composed of the driven lubricating bearing and the baffle connected to the bearing positioning device; there are rectangular holes on both sides of the self-lubricating bearing device; the active lubricating bearing and the driven lubricating bearing are both composed of the upper half bearing body and the lower half bearing body through mortise joints Way to connect composition.

The inner walls of the active lubricating bearing and the driven lubricating bearing are both provided with arc-shaped water tanks, and the number of water tanks is 6.

The lower half bearing body of the active lubricating bearing has a flat bottom, the upper half bearing body of the driven lubricating bearing has a flat bottom, and the flat bottom surfaces of the two half bearing bodies contact each other to form a support to reduce deformation in the middle of the screw.

The material of the upper half bearing body and the lower half bearing body is ultra-high relative molecular mass polyethylene material.

The middle parts of the driving screw and the driven screw are optical axis structures, and the optical axis structure forms a clearance fit with the inner diameters of the active lubricating bearing and the driven lubricating bearing.

The beneficial effects of the present invention are: the self-lubricating bearing variable volume novel twin-screw pump proposed by the present invention has a novel structure and a clear working principle. There is a self-lubricating bearing device in the middle. The driving screw and the driven screw rotate in the opposite direction, and the conveying medium enters from the large pitch end. The cavity formed by the driving screw, the driven screw and the pump chamber, with the relative rotation of the screw, the thread Continuously squeeze the cavity body to move the cavity body towards the small pitch end until output. During this process, the volume of the cavity body gradually decreases, which gives effective pre-compression to the conveying medium, and changes the fixed pitch of the screw by changing the screw pitch. Volume, so that it can reduce the deformation of the middle part of the screw in the working process of the twin-screw pump, reduce the vibration and noise when transporting gas-liquid medium, improve the stability of the screw pump transmission, and increase the bearing capacity of the gear, thereby improving the performance of the screw pump. work efficiency.

The specific beneficial effects are as follows:

1. The pitch of the screw used is evenly reduced, so that the conveying medium is pre-compressed in the pump cavity, which can suppress the surge at the output port, so that the pump works more smoothly and reduces vibration and noise.

2. It adopts double-arc gear transmission, the transmission is relatively stable, and the vibration and noise are small. In addition, due to its large tooth root thickness, its load-carrying capacity is also high.

3. The self-lubricating bearing of the twin-screw pump makes the main and slave screws support each other, thereby reducing the deformation of the middle part of the screw and improving the working efficiency of the twin-screw pump.

4. The self-lubricating bearing of the twin-screw pump in the present invention is made of composite materials. When the screw pump works, a layer of lubricating water film can be formed on the bearing surface, so that the bearing forms self-lubrication and reduces the wear of the screw.

Description of drawings

Fig. 1 is a schematic diagram of the assembly structure of the present invention.

Fig. 2 is a schematic diagram of the flow direction of the medium flowing through the self-lubricating bearing device in the present invention.

Fig. 3 is a schematic diagram of the meshing structure of the driving screw and driven screw with variable pitch in the present invention.

Fig. 4 is a schematic diagram of other methods for changing the volume of a screw pump involved in the present invention.

Fig. 5 is a schematic diagram of the gear meshing structure in the present invention.

Fig. 6 is a schematic structural diagram of the self-lubricating bearing device in the present invention.

Fig. 7 is a schematic diagram of the connection structure between the upper half bearing body and the lower half bearing body in the present invention.

In the figure: driven gear 1, driven gear bushing 1-1, driven gear flat key 1-2, driving gear 2, driving gear bushing 2-1, gear sleeve 2-2, fastening bolt 2-3 , Locking round nut 2-4, flat key 2-5, rear end cover 3, rear support cover 4, locking bolt 5, driven screw 6, driving screw 7, left pump housing 8, self-lubricating bearing device 9 , Bearing positioning device 9-1, set screw 9-2, upper half bearing 9-3, driving screw intermediate optical axis 9-4, lower half bearing 9-5, driven screw intermediate optical axis 9-6, baffle 9-7. Right pump housing 10, front support cover 11, front end cover 12, support bearing 13, medium input end 14, and medium output end 15.

detailed description

The present invention will be further described below in conjunction with accompanying drawing:

As shown in Figure 1-7, the self-lubricating new type variable volume twin-screw pump includes a twin-screw pump casing; the twin-screw pump casing is composed of a left pump casing 8 and a right pump casing 10, and the left pump casing 8 is provided with a medium input end 14, and the right pump housing 10 is provided with a medium output end 15, and the connection between the left pump housing 8 and the right pump housing 10 is provided with a self-lubricating bearing device 9 inside, and the left pump housing 8 is connected to the right pump housing 10. The right pump housing 10 is provided with a variable-pitch driving screw 7 and a driven screw 6. The outer contours of the driving screw 7 and the driven screw 6 match the inner wall of the twin-screw pump housing, and the ends of the left pump housing 8 are connected. There is a rear supporting cover 4, and the driving gear 2 and the driven gear 1 are arranged in the rear supporting cover 4, the driving gear 2 is connected with the driving screw 7, the driven gear 1 is connected with the driven screw 6, and the rear supporting The end face of the cover 4 is provided with a rear end cover 3, and the end of the right pump housing 10 is connected with a front support cover 11, and the end face of the front support cover 11 is provided with a front end cover 12, and the head of the driving screw 7 extends out of the front end cover 12. As the power input end of the twin-screw pump, the rear end cover 3, the rear support cover 4, the left pump housing 8, the right pump housing 10, the front support cover 11 and the front end cover 12 form a closed cavity through a mechanical seal.

As shown in Figure 1-7, the self-lubricating new type variable volume twin-screw pump, the driving screw 7 and the driven screw 6 are single-headed screws with uniform variable pitch, the tooth profile is trapezoidal, and the driving screw 7 is a convex trapezoid tooth, the driven screw 6 is a concave trapezoidal tooth, and the driving screw 7 and the driven screw 6 mesh with each other; the uniform variable pitch is the change of the pitch of the driving screw 7 and the driven screw 6 from large to small, and the initial pitch is p , the lift distance is d, the number of upper teeth of the screw is n, and the pitch from large to small is p+nd, p+(n-1)d, p+(n-2)d, p+(n-3)d and so on; active Both gear 2 and driven gear 1 are double-arc gears, the modulus and number of teeth of driving gear 2 and driven gear 1 are equal, and driving gear 2 is connected with driving screw 7 through gear sleeve 2-2, and gear sleeve 2-2 Connect with the driving screw 7 through the flat key 2-5; the axial direction of the driving gear 2 and the driven gear 1 are respectively provided with a bushing 2-1 and a locking round nut 2-4; the self-lubricating bearing device 9 is located in the left pump casing 8 and the right pump housing 10, and embedded in the left pump housing 8 and the right pump housing 10; the self-lubricating bearing device 9 is composed of a bearing positioning device 9-1, an active lubricating bearing arranged in the bearing positioning device 9-1 It is composed of the driven lubricating bearing and the stopper 9-7 connected to the bearing positioning device 9-1; the two sides of the self-lubricating bearing device 9 have rectangular holes; -3 and the lower half bearing body 9-5 are connected by mortise joints; the inner walls of the active lubricating bearing and the driven lubricating bearing are equipped with arc-shaped water tanks, and the number of water tanks is 6; the lower half bearing body of the active lubricating bearing 9-5 is a flat bottom, and the upper half bearing body 9-3 of the driven lubricating bearing is a flat bottom, and the flat bottom surfaces of the two half bearing bodies contact each other to form a support to reduce the deformation of the middle part of the screw; the upper half bearing body 9-3 and the lower The material of the half-bearing body 9-5 is an ultra-high molecular weight polyethylene material; the middle parts of the driving screw 7 and the driven screw 6 are optical axis structures, and the optical axis structure is formed with the inner diameters of the active lubricating bearing and the driven lubricating bearing. Clearance fit.

As shown in Figure 2, the self-lubricating support variable volume new twin-screw pump, in order to facilitate the installation of the self-lubricating bearing device 9, the twin-screw pump housing is divided into two parts 8 and 10. The input end and the output end are on the shell 8 and the shell 10 respectively, and the liquid enters the pump cavity through the inlet of the screw pump shell 8, and is discharged from the outlet of the shell 10, and the flow direction is shown by the arrow in Fig. 2 .

As shown in Figure 3, a new variable volume twin-screw pump with self-lubricating support, taking the pitch of the active screw as an example, the screw pitch is the initial pitch is p, and the lift is d. Other variable volume schemes are shown in Figure 4-a, 4- As shown in b and 4-c, in Figure 4-a, by changing the depth of the screw groove, the paired screw increases or decreases △d respectively; in Figure 4-b, by changing the width of the screw groove, the paired screw increases or decreases Δt respectively, Figure 4-c The variable volume is realized through the taper of the screw.

As shown in Figure 5, the variable volume double-screw pump with self-lubricating support, the casing 10 and the support bearing 13 provide support for the screw; the main and driven screws 7 and 6 mesh with each other; the driving gear connected with the driving screw 7 2. The driving gear 2 is connected with the driving screw 7 through the gear sleeve 2-2, and the gear sleeve 2-2 is connected with the driving screw 7 with a flat key 2-5. Sleeve 2-1 and locking round nut 2-4; driven screw 6 is connected with driven gear 1 through key 1-2, in order to prevent driven gear 1 from moving axially, bushing 1-1 and lock Tight round nuts 1-4.

As shown in Figure 6, the variable volume double-screw pump with self-lubricating support consists of two integral bearings formed by the upper half bearing body 9-3 and the lower half bearing body 9-5 through tenon joints, and the two integral bearings are placed on the self-lubricating shaft. In the lubricating bearing positioning device 9-1, the positioning device 9-1 provides support to prevent the radial movement of the bearing; the stopper 9-7 is fixed on the positioning device 9-1 by the set screw 9-2 to prevent the bearing from moving axially. move. The inner diameter of the self-lubricating bearing is clearance fit with the middle part of the driving screw 7 and the driven screw 6, and the outer contour 9-1 of the self-lubricating bearing positioning device is matched with the combined screw pump housing 8,10 internal grooves. At the same time, there are rectangular holes on both sides of the self-lubricating bearing positioning device 9-1 to facilitate the circulation of liquid.

When the screw rods are engaged, the liquid flowing through the housing 8 flows into the cavity of the housing 10 through the rectangular holes on both sides of the self-lubricating bearing positioning device 9-1, and then the liquid flows from both ends to the output end. At the same time, due to the torque and pressure difference during meshing, the middle part of the screw is easily deformed. After installing the self-lubricating bearing device, it provides support for the middle part of the screw, which can effectively reduce the deformation.

As shown in Figure 1, the working principle of the new self-lubricating variable volume twin-screw pump is as follows: There are two meshing variable-pitch trapezoidal screws in the twin-screw pump body, and the outer circumference of the screw cooperates with the pump chamber. There is a single-head thread, the large pitch is the input port, and the end of the small pitch is the output port. There are support covers at both ends of the pump body. The shaft of the screw is rotatably supported on the support cover. The cover serves as the power input. When working, input power from the driving screw, the driving gear transmits torque through the flat key between the driving screw and the gear sleeve, the gear sleeve and the driving gear are connected and compressed by fastening bolts, and the driving gear and the driven gear are meshed and transmitted Torque, the driven gear transmits torque through the key between the driven screw, and the synchronous gear drives the driven screw to rotate in the opposite direction. With the relative rotation of the screw, a closed cavity is continuously formed on the input side of the large pitch , the cavity moves toward the air outlet with gradually smaller pitch. During the moving process, due to the continuous reduction of the pitch, the volume of the unit cavity will gradually decrease, resulting in a continuous increase in pressure, and the expected pressure value will be reached at the output port.

The foregoing description is only a description of the preferred embodiments of the present invention, and is not any limitation to the scope of the present invention. Those skilled in the art of the present invention can make modifications according to the foregoing, especially by changing the groove depth, groove width or screw taper of the screw groove. To change the volume of the twin-screw pump, all belong to the scope of protection of the present invention.

Claims (10)

1. the capacity new-type double screw pump of self-lubricating supporting, including Quimby pump housing；It is characterized in that：The Quimby pump Housing is connected and composed by left pump case (8) and right pump case (10), and the left pump case (8) is provided with medium input (14), The right pump case (10) is provided with medium output end (15), the left pump case (8) with inside right pump case (10) junction Provided with self-lubricating bearing device (9), the left pump case (8) is with running through the driving screw rod provided with varying pitch in right pump case (10) (7) match with driven screw (6), the outline and Quimby pump inner walls of the driving screw rod (7) and driven screw (6) Close, left pump case (8) end is connected with rear support lid (4), and the driving tooth being meshed is provided with the rear support lid (4) Take turns (2) and driven gear (1), the driving gear (2) acts on the driving screw rod (7) to be connected, the driven gear (1) and Driven screw (6) effect is connected, and the end face of the rear support lid (4) is provided with rear end cap (3), the right pump case (10) End is connected with front support lid (11), and the end face of the front support lid (11) is provided with drive end bearing bracket (12), the driving screw rod (7) Head stretch out the power intake of the drive end bearing bracket (12) as Quimby pump, the rear end cap (3), rear support lid (4), a left side Pump case (8), right pump case (10), front support lid (11) and drive end bearing bracket (12) form the cavity of closing by mechanical seal.

2. the capacity new-type double screw pump of self-lubricating supporting according to claim 1, it is characterised in that：The active spiral shell Bar (7) and driven screw (6) are all the single-head screws of uniform varying pitch, and tooth form is trapezoidal, and driving screw rod (7) is convex trapezoidal Tooth, driven screw (6) are recessed stepped tooth, and driving screw rod (7) is intermeshed with driven screw (6).

3. the capacity new-type double screw pump of self-lubricating supporting according to claim 1, it is characterised in that：The varying pitch Be driving screw rod (7) and driven screw (6) since fluid inlet end to the port of export, its pitch is descending progressively to be become Change, the change of pitch is a fixed value in a small amount, and the initial designs pitch for making screw spiral tooth form is p, and the pitch of each circle becomes a small amount of For d.

4. the capacity new-type double screw pump of self-lubricating supporting according to claim 1, it is characterised in that：The driving tooth Wheel (2) and driven gear (1) are Novikov gears with double circular arc tooth profiles, and the modulus of driving gear (2) and driven gear (1), the number of teeth are equal, are led Moving gear (2) is connected by geared sleeve (2-2) with driving screw rod (7), and geared sleeve (2-2) passes through flat key (2-5) and driving screw rod (7) connect.

5. the capacity new-type double screw pump of self-lubricating supporting according to claim 1, it is characterised in that：The driving tooth The axial direction of wheel (2) and driven gear (1) sets bushing (2-1) and stripped nut (2-4) respectively.

6. the capacity new-type double screw pump of self-lubricating supporting according to claim 1, it is characterised in that：The self-lubricating Bearing arrangement (9) is between left pump case (8) and right pump case (10), and embedded left pump case (8) and right pump case (10) It is interior；Self-lubricating bearing device (9) is by bearing positioning device (9-1), the active lubrication axle being arranged in bearing positioning device (9-1) Hold and driven lubrication bearing and catch (9-7) composition being connected with bearing positioning device (9-1)；Self-lubricating bearing device (9) Both sides be provided with rectangular opening；Active lubrication bearing and driven lubrication bearing are by upper half bearing body (9-3) and bottom half-bearing body (9- 5) connected and composed by dovetail manner.

7. the capacity new-type double screw pump of self-lubricating supporting according to claim 6, it is characterised in that：The active profit The inwall of plain besring and driven lubrication bearing is equipped with circular arc tank, the bar number of tank 6.

8. the capacity new-type double screw pump of self-lubricating supporting according to claim 6, it is characterised in that：The active profit The bottom half-bearing body (9-5) of plain besring is flat, and the upper half bearing body (9-3) of driven lubrication bearing is flat, two half-and-half bearings The planar base surface of body contacts with each other to form support, to reduce the deformation in the middle part of screw rod.

9. the capacity new-type double screw pump of self-lubricating supporting according to claim 6, it is characterised in that：The upper semiaxis The material for holding body (9-3) and bottom half-bearing body (9-5) is ultra high molecular weight polyethylene material.

10. the capacity new-type double screw pump of self-lubricating supporting according to claim 1, it is characterised in that：The active The middle part of screw rod (7) and driven screw (6) is plain shaft structure, plain shaft structure and active lubrication bearing, driven lubrication axle The internal diameter held forms gap and coordinated.