JP7158052B2 - twin screw pump - Google Patents

Description

TECHNICAL FIELD The present invention relates to a twin-screw pump that transfers a viscous fluid, which is an object to be transferred, with a high level of defoaming ability without altering the physical properties of the fluid.

Conventionally, as this kind of twin-screw pump, one described in Patent Document 1 below is known. The twin-screw pump described in the document is a twin-screw pump with a degassing device, and as shown in FIGS. and between the tip surfaces 7B, 7B of the pump screws 7a, 7b and the inner peripheral surface 2A of the pump casing, respectively, gaps G, H are formed through which gas such as air can pass but viscous fluid cannot pass. . In this device, the viscous fluid is transferred while discharging the gas in the viscous fluid out of the machine by driving the degassing device connected to the gas extraction port of the pump casing. Although it is a positive displacement pump having pump screws 7a and 7b, it has the function of discharging and transferring gas from a viscous fluid.

JP 2015-55179 A

However, the twin-screw pump described in Patent Document 1 described above has a large number of bubbles scattered in the dispersion medium, and when transferring a highly viscous fluid that is stably stationary and does not move, the Since the viscous fluid is transferred in the helical space of the pump chamber while being held in its spatial shape, the air bubbles hardly move in the viscous fluid, and the air bubbles partially remain. There was a problem that the air could not be fully released.

The present invention has been made in view of the conventional problems described above. An object of the present invention is to provide a twin-screw pump capable of degassing to a higher degree.

In order to achieve the above object, a twin screw pump according to the present invention includes a pair of pump screws that are screwed together in a non-contact manner and rotationally driven, and a cylindrical pump that accommodates the pair of pump screws in a non-contact manner. a casing, a viscous fluid intake port provided in the middle of the pump casing in the axial direction, a viscous fluid discharge port provided on the tip side of the pump casing, and a top surface of the pump casing on the distal side of the viscous fluid intake port. and a degassing device connected to the gas outlet provided in a pair of pump screws, between the side surfaces of a pair of pump screws, and between the tip surface of each pump screw and the inner peripheral surface of the pump casing. A twin-screw pump having a gas-permeable but viscous-fluid-impermeable gap between them, wherein the viscous fluid intake of the pump casing has an increased surface area per unit volume of the viscous fluid. A distributing member having surface area increasing means for flowing into the casing, wherein the surface area increasing means diverts the viscous fluid to limit the flow rate of the viscous fluid taken in from the viscous fluid intake before flowing into the pump casing. The dispersing member includes a plate-like body that covers the viscous fluid intake, a valve seat hole formed through the plate-like body through the front and back, and the inner peripheral surface of the valve seat hole. A valve body arranged with a passage gap through which a fluid can pass; and a fixing member for fixing the valve body to the plate-like body. It is characterized in that it is configured to flow into the casing .

Further, the above configuration is characterized by comprising a gap variable mechanism for varying the size of the passage gap by moving the outer peripheral surface of the valve body closer to and away from the inner peripheral surface of the valve seat hole. .

The twin-screw pump according to the present invention includes a pair of pump screws that are screwed together in a non-contact manner and rotationally driven, a cylindrical pump casing that accommodates the pair of pump screws in a non-contact manner, and A viscous fluid intake port provided midway in the axial direction, a viscous fluid discharge port provided on the tip side of the pump casing, and a gas vent provided on the distal side of the viscous fluid intake port on the upper surface of the pump casing. An outlet and a degassing device connected to the gas outlet for allowing gas to pass between the side surfaces of the pair of pump screws and between the tip surface of each pump screw and the inner peripheral surface of the pump casing. A twin-screw pump with a viscous fluid impervious clearance that allows the viscous fluid intake of the pump casing to increase the surface area per unit volume of the viscous fluid to flow into the pump casing. The surface area increasing means restricts the viscous fluid taken in from the viscous fluid intake to a channel cross-sectional area smaller than the flow channel cross-sectional area of the viscous fluid intake before allowing it to flow into the pump casing. A ring-shaped plate-shaped main body that covers a viscous fluid intake, a bottomed cylindrical cylindrical body part that is vertically provided on the inner peripheral edge of the plate-shaped main body, and a fluid throttle member. a passage hole having an opening area smaller than the flow channel cross-sectional area of the cylindrical body portion, the viscous fluid in the cylindrical body portion passing through the through hole. It is characterized in that it flows into the pump casing after passing through.

Further, in the above configuration, the passage hole of the cylindrical body portion is formed in a slit shape, and the passage hole extends in the axial direction of the pump casing in a state where the fluid throttle member is arranged in the viscous fluid intake port. It is characterized in that it is arranged in a direction perpendicular to the

A twin-screw pump according to the present invention is a positive displacement pump containing a pair of pump screws that are not in contact with each other. After the surface area per unit volume is increased by the means, it is sent into the pump casing. Therefore, the increased surface area makes it easier for bubbles to be extracted from the viscous liquid, and more bubbles can be extracted from the gas extraction port. As a result, it is possible to supplement the original degassing ability and perform degassing at a higher level.

Further, since the surface area increasing means is composed of the dispersing member, the viscous fluid flowing into the viscous fluid intake is divided by the distributing member and sent into the pump casing after the flow rate is restricted. At this time, since the total open area of the plurality of passage holes is smaller than the channel cross-sectional area of the viscous fluid intake, the surface area of the viscous fluid flowing in per unit time passes through the plurality of passage holes. before and after becomes larger. Due to these, the viscous fluid is fluidized, and the bubbles in the viscous fluid are encouraged to collide with each other to increase the diameter of the bubbles. more air bubbles in the viscous fluid can be degassed .

The dispersing member comprises a plate-like body covering the viscous fluid intake, a valve seat hole formed in the plate-like body, and a valve body arranged between an inner peripheral surface of the valve seat hole, and a valve body. to the plate-like body, a passage gap for the viscous fluid can be provided between the valve seat hole and the valve body, and the viscous fluid can pass through this passage gap. By dispersing the viscous fluid, high degassing can be performed.

Furthermore, in the case of a valve having a variable clearance mechanism for changing the passage clearance between the outer peripheral surface of the valve body and the inner peripheral surface of the valve seat hole, the outer peripheral surface of the valve body is moved toward and away from the inner peripheral surface of the valve seat hole. Since the size of the passage gap can be changed to an appropriate size that matches the viscosity of the viscous fluid, the viscous fluid can be degassed with an appropriate degassing capacity. can do.

Further, in the twin-screw pump in which the surface area increasing means is composed of a fluid throttle member, the viscous fluid flowing into the viscous fluid inlet is caused to flow through the passage hole of the fluid throttle member so that the cross-sectional area of the viscous fluid inlet is reduced. Since the cross-sectional area of the flow path is also narrowed down, the surface area of the viscous fluid that has passed through the passage hole is increased. As a result, more degassing can be done from the viscous fluid.

In the above configuration, the fluid restricting member includes a plate-like main body covering the viscous fluid inlet, a bottomed tubular portion, and a passage hole formed in the bottom surface of the tubular portion. As a result, it is possible to increase the surface area of the viscous fluid, which is taken in by squeezing the viscous fluid through the passage holes, while maintaining a simple and inexpensive structure, and performing advanced degassing.

Furthermore, in the above configuration, if the passage hole in the cylindrical body portion is formed in a slit shape and the passage hole is arranged so that the longitudinal direction of the slit is oriented in a direction perpendicular to the axis of the pump casing, Since the distance from any position of the hole to the gas extraction port is substantially the same, the viscous fluid can be efficiently degassed regardless of the passage position of the passage hole.

1 is a side configuration diagram showing a twin screw pump according to an embodiment of the present invention; FIG. It is a front block diagram which shows the said twin-screw pump. It is an internal plane block diagram including the partial cross section of the said twin-screw pump. 4 is an internal configuration diagram of the twin-screw pump and is a cross-sectional view taken along the line AA in FIG. 3. FIG. Fig. 3 is a view for explaining a gap in the twin-screw pump, where (a) is a partially enlarged plan view showing a gap between a pair of pump screws, and (b) is a gap between the pump screw and the inner peripheral surface of the pump casing. is a partially enlarged plan view showing a gap between. FIG. 2 is a side configuration diagram including a partial cross-section in which a main portion of the twin screw pump is disassembled; FIG. 4 is a diagram showing a reference example of a dispersing member of the twin screw pump, where (a) is a plan view and (b) is a cross-sectional view taken along the line BB in (a). (a) is an X-ray image of the fish sausage obtained by the twin-screw pump of this embodiment , and (b) is an X-ray image of the fish sausage obtained by the conventional twin-screw pump. is. (a) is a partial plan view of the fish sausage meat obtained by the twin-screw pump of the embodiment and spread in half, and (b) is the fish sausage meat obtained by the conventional twin-screw pump. It is a partial plan view that is split in half and spread out. FIG. 3 is a view showing the dispersing member of the twin screw pump, where (a) is a plan view of the dispersing member used as a reference example in the embodiment, and (b) to (d) are deformations of the dispersing member of (a). FIG. 10 is a plan view showing examples of dispersing members with successively smaller hole widths; (a) to (d) are plan views respectively showing reference examples of other dispersing members that can be used in the twin-screw pump. BRIEF DESCRIPTION OF THE DRAWINGS It is a partial side view including a partial cross section which shows the principal part of the twin-screw pump which concerns on Embodiment 1 of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the component of the twin-screw pump of Embodiment 1 , (a) has shown the valve body, (1) is a top view, (2) is a side view, (3) is a bottom view, (b) ) shows a fixing member, (1) is a plan view, (2) is a cross-sectional view taken along line CC in (1), (3) is a bottom view, and (c) shows a plate-like body. (1) is a plan view, and (2) is a cross-sectional view taken along line DD in (1). 4 is a partial side cross-sectional view for explaining the operation of the essential parts of the twin screw pump of Embodiment 1. FIG. Fig. 10 is a view showing a fluid throttle member used in a twin-screw pump according to Embodiment 2 of the present invention, where (a) is a perspective view looking up obliquely from below, and (b) is a perspective view looking down obliquely from above. be. FIG. 10 is a view showing a fluid throttle member of a twin screw pump of Embodiment 2 , (a) is a plan view, (b) is a cross-sectional view taken along line EE in (a), and (c) is (a). 2 is a cross-sectional view taken along the line FF in FIG. FIG. 8 is an exploded rear view including essential parts of the twin-screw pump of Embodiment 2 ; FIG. 18 is a cross-sectional view taken along line RR in FIG. 17 of the twin screw pump of Embodiment 2 ; Fig. 10 is a rear view showing a state in which essential parts of the twin-screw pump of Embodiment 2 are assembled; 3A is a plan view of a fluid throttle member used in a twin screw pump according to Embodiment 3 of the present invention, and FIG. (c) is a cross-sectional view taken along the line HH in (a), and (d) is a cross-sectional view taken along the line II in (a).

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. It should be noted that the embodiment described below is merely an example that embodies the present invention, and does not limit the technical scope of the present invention. 1 is a side configuration diagram showing a twin screw pump according to an embodiment of the present invention, FIG. 2 is a partial front configuration diagram showing the twin screw pump, and FIG. 3 is a main part of the twin screw pump. 4 is an internal configuration diagram of the twin-screw pump, which is a cross-sectional view taken along the line AA in FIG. 3. FIG.

" Embodiment. "
1 to 4, the twin-screw pump 1 according to this embodiment includes a cylindrical pump casing 2 penetrating in the front-rear direction, and a bearing 5 connected to the rear end of the pump casing 2. there is A discharge-side casing 3 is connected to the front end portion of the pump casing 2 , and a pipe portion 4 is connected to the front end portion of the discharge-side casing 3 . A pair of pump screws 7a and 7b are accommodated in the pump casing 2. As shown in FIG. The front ends of the pump screws 7a, 7b fixed to the shafts 8a, 8b by setscrews or the like form free ends 26, 26 which are not supported by bearings or the like. The free ends 26, 26 of these pump screws 7a, 7b are applied with fixing plates 14, 14 and fixed to the shafts 8a, 8b by bolts 15, 15, for example. The spiral direction of the pump screw 7a and the spiral direction of the pump screw 7b are opposite.

The bearing portion 5 is formed in a box shape by a housing 9 and a cover plate 10 , and the front end face of the cover plate 10 is connected to the cylindrical end face of the pump casing 2 . Conical roller bearings 11 and 11 and roller bearings 12 and 12 are arranged in the housing 9 . These roller bearings 11 and 12 rotatably support the rear end portion of the shaft portion 8a of the pump screw 7a in a cantilever manner. The rear end portion of the shaft portion 8b of the pump screw 7b is also rotatably supported in a cantilever manner by separate conical roller bearings 11 and 12. As shown in FIG. That is, the rear portions of the pump screws 7a and 7b are supported at two points within the housing 9 so as to be freely rotatable. Sealing mechanisms 16, 16 are mounted on the pump screws 7a, 7b in the vicinity of the cover plate 10 within the housing 9. As shown in FIG. A synchronous gear 13a is fixed to the shaft portion 8a of the pump screw 7a, and a synchronous gear 13b that meshes with the synchronous gear 13a is fixed to the shaft portion 8b of the pump screw 7b. Due to the synchronous meshing of the synchronous gears 13a and 13b, the pair of pump screws 7a and 7b are in quasi meshing without coming into contact with each other at any rotation angle. That is, the pump screws 7a and 7b rotate while being screwed together without contact. In this case, for example, the shaft portion 8a of the pump screw 7a serves as a drive shaft and is connected to the motor M via a connection mechanism 30 such as a speed reduction mechanism.

The pump casing 2 is formed with a cocoon-shaped pump chamber 6 penetrating therethrough in the front-rear direction. A cylindrical discharge-side casing 3 is connected to the front end of the pump casing 2 . A tubular pipe portion 4 having a viscous fluid discharge port 19 is connected to the front end portion of the discharge side casing 3 . One end of a vent pipe 34 is connected to the tip of the pipe portion 4 , and a check valve 36 is connected to the other end of the vent pipe 34 . The output side of the check valve 36 is connected to a pipe portion 35 that is connected to a fluid transfer destination. The check valve 36 allows the viscous fluid Q to flow only in the viscous fluid transfer direction (black arrow direction), and is normally closed by the spring elastic force of the spring member. The pump chamber 6 accommodates a pump screw 7a that rotates about the axis Xa and a pump screw 7b that rotates about the axis Xb while constantly screwing the pump screw 7a in a non-contact manner. The outer peripheral surfaces of the pair of pump screws 7a and 7b are always kept out of contact with the inner peripheral surface 2A of the pump chamber 6 as will be described in detail later. On the other hand, a viscous fluid inlet 18 communicating between the pump chamber 6 and the hopper 24 is formed on the upper surface of the pump casing 2 at a position slightly behind the front-rear central portion.

A flange receiving portion 50 is formed on the upper surface of the pump casing 2 surrounding the viscous fluid inlet 18 . The inside of the flange receiving portion 50 connecting the viscous fluid intake port 18 and the pump chamber 6 serves as an introduction path 86 for introducing the viscous fluid Q from the pipe portion 21 into the pump chamber 6 . A flange of the pipe portion 21 is fixed to the flange receiving portion 50 with a bolt 51 . Then, the ferrule joint portion of the pipe portion 21 and the lower ferrule joint portion of the pipe portion 53 are fixed by the clamp band 54, and the ferrule joint portion of the hopper 24 is applied to the upper ferrule joint portion of the pipe portion 53. It is fixed with a clamp band (not shown). Thereby, the hopper 24 and the viscous fluid intake 18 are communicated with each other. On the other hand, in the ceiling surface of the rear end portion of the pump chamber 6, a laterally extending ventilation groove 23 is formed by recessing upward. A gas extraction port 20 is formed in the pump casing 2 above the ventilation groove 23 to communicate the ventilation groove 23 with the upper outside of the casing. That is, a gas extraction port 20 for extracting gas from the pump chamber 6 is formed in the pump casing 2 upstream of the viscous fluid intake port 18 in the viscous fluid transfer direction. A degassing device 27 for extracting gas from the pump chamber 6 is connected to the gas extraction port 20 via a communication passage 29 such as a pipe member. As the degassing device 27, for example, an air ejector type is used here, but a piston-cylinder type or centrifugal fan type decompression pump may be used.

The pair of pump screws 7a, 7b has spiral screw teeth formed on the outer peripheral surfaces of cylindrical bases 7A, 7A through which the shafts 8a, 8b are inserted. Then, as shown in FIG. 5(a), a gap G is provided between the side surface 7Sa of the screw teeth of the pump screw 7a and the side surface 7Sb of the screw teeth of the pump screw 7b so that they are always out of contact. . A gap H is provided between the outer peripheral surface 7B of the screw teeth of the pump screws 7a and 7b and the inner peripheral surface 2A of the pump chamber 6 of the pump screw 2, as shown in FIG. 5(b). Always contactless. In other words, these gaps G and H always exist regardless of the rotational angle of the pair of pump screws 7a and 7b. Both of the gaps G and H are set to a gap width that allows the gas K such as air to pass through but does not allow the high-viscosity liquid of the viscous fluid Q and hard/soft solids to pass through. In this case, the gap width of the gap G is, for example, 0.03 to 0.09 mm, and the gap width of the gap H is, for example, 0.12 to 0.18 mm. The pair of pump screws 7a and 7b produce a pump action capable of transferring the viscous fluid Q within the region P shown in FIGS. Within the area P, the area pa shown in FIGS. 3 and 4 is upstream of the viscous fluid intake port 18 . When the twin-screw pump 1 is used for transporting foods, medicines, cosmetic materials, etc., from the viewpoint of sanitation and maintenance of product physical properties, the parts that come into direct contact with the viscous fluid Q should be made of stainless steel. It is desirable to use The rated pump capacity of the twin screw pump 1 is, for example, 10 to 120 L/min.

On the other hand, in the twin-screw pump 1, as shown in FIG. 6, a dispersing member 40, which is a reference example of the surface area increasing means 77, is arranged on the inlet side of the viscous fluid intake 18 of the pump casing 2. As shown in FIG. As shown in FIG. 7, the dispersing member 40 includes a disc-shaped plate-like main body 42 that covers the viscous fluid intake 18 of the pump casing 2, and is recessed downward from the upper surface of the plate-like main body 42 into the plane central portion of the plate-like main body 42. a plurality of passage holes 41, 41, 41, . 42 and bolt insertion holes 43, 43, 43, 43 through which the bolts 51 are passed. The thickness t of the dispersion member 40 is, for example, 5 mm. In this case, the ^total number of passage holes 41, 41, 41, . . . The open hole area B (cross-sectional area of flow path) [hole width Y×(sum of longitudinal dimensions of passage holes 41)] is smaller.

The operation of the twin-screw pump 1 constructed as described above will now be described. Examples of the high-viscosity viscous fluid Q used for transportation include foods such as fish sausage raw materials, miso, starch syrup, butter, and molten chocolate, cosmetics such as creams and lotions, industrial materials such as molten synthetic resins, and medical materials. etc. As the viscous fluid Q having a high viscosity, one having a relative viscosity of, for example, 1 to 1,000,000 Pa·s can be used. The handling temperature of the viscous fluid Q varies depending on the type of fluid, but is, for example, normal temperature to about 200.degree. Here, an example using "fish meat sausage raw material before casing filling" having a relative viscosity of, for example, 1,000,000 Pa·s is shown. In the viscous fluid Q (see FIG. 1) in the hopper 24, many bubbles 73, 73, 73, .

When the pump screw 7a is rotated in one direction by the rotational driving of the motor M, the pump screw 7b to which power is transmitted through the synchronous gears 13a and 13b is synchronously rotated in the opposite direction. The rotational speed of the pump screws 7a, 7b is, for example, 100-1000 rpm. On the other hand, when the viscous fluid Q is put into the hopper 24 , the viscous fluid Q flows from the hopper 24 into the pipe portion 21 through the pipe portion 53 . After that, the viscous fluid Q in the pipe portion 21 flows into the plurality of passage holes 41, 41, 41, . . . . . , respectively, join again before the viscous fluid intake 18 as inflowing viscous fluids N, N, N, . . . (see FIG. 7(b)). In this case, the inflow amount of the viscous fluid Q per unit time (unit volume referred to in the present invention) in the pipe portion 21 is calculated by [(diameter L/2) ² π inflow length J]. Since the total opening area B of the passage holes 41, 41, 41, . It is longer than the inflow length J of the viscous fluid Q. As a result, the surface area per unit volume of the inflowing viscous fluid N [(2.(hole width Y of each passage hole 41 + hole longitudinal dimension). J1)] is wider.

The viscous fluid Q dispersed and rejoined by the dispersion member 40 in this way flows into the pump chamber 6 of the pump casing 2 via the viscous fluid inlet 18 . On the other hand, by driving the degassing device 27, the gas (mostly air) inside the pump casing 2 is extracted from the gas extraction port 20, and the pressure inside the pump chamber 6 is reduced. At this time, the degree of pressure reduction by the deaerator 27 is, for example, -0.01 to -0.04 MPa (complete vacuum = -0.1 MPa). On the other hand, the viscous fluid Q is sent toward the discharge side casing 3 by the pump action of the pump screws 7a and 7b (in the direction of the black arrow F).

In this case, the viscous fluid Q passes through the passage holes 41, 41, 41, . . . Since the inside of the pump chamber 6 is evacuated by the degassing device 27, the bubbles that have passed through the dispersing member 40 and become large particles move through the viscous fluid Q in the viscous fluid transfer direction (painted black). The direction of the arrow F) is easily moved in the opposite direction (the direction of the white arrow, that is, toward the upstream side in the transfer direction). At this time, fine air bubbles also form a gap H between the inner peripheral surface 2A of the pump casing 2 and the outer peripheral surface 7B of the pump screws 7a and 7b (see FIG. 5(b)), the side surface 7Sa of the pump screw 7a and the pump screw 7b. 5A) and moves backward in the area pa. Thereafter, the air bubbles that have moved are sucked out through the communication passage 29 from the gas extraction port 20 by the action of the degassing device 27 and are discharged to the outside of the machine. As a result, the viscous fluid Q from which a large amount of gas has been removed is delivered from the viscous fluid discharge port 19 to the check valve 36 . The check valve 36, which has been closed by its own spring member, opens against the spring elastic force of the spring member when the pressure on the inlet side reaches a positive pressure of 0.05 MPa, for example, and the viscous fluid Q to the pipe section 35. The viscous fluid Q from the tube section 35 is sent as fish material to a filling machine for filling sausage casings, for example.

The viscous fluid Q sent as described above is filled into a flexible tubular casing by a stuffing machine, and both ends of the tubular casing are sealed with retaining rings to form fish sausage (A). When the resulting fish sausage (A) was photographed with an X-ray apparatus, an X-ray photograph as shown in FIG. 8(a) was obtained. This X-ray photograph showed a casing image 60, a retaining ring image 61 and a fish meat image 62A, but no bubbles were observed in the fish meat image 62A.
On the other hand, the viscous fluid Q was defoamed and conveyed by a conventional twin-screw pump that did not use the dispersing member 40 to obtain a fish sausage (B). When the fish sausage (B) was photographed with an X-ray apparatus, an X-ray photograph as shown in FIG. 8(b) was obtained. The X-ray photograph of this fish sausage (B) shows a casing image 60, a retaining ring image 61, and a fish meat image 62. In the fish meat image 62, several bubble images 63 were observed.

Furthermore, the fish meat was exposed by removing the casing and the retaining ring from the fish sausage (A) obtained using the dispersion member 40 as described above. Fig. 9(a) shows the fish meat cut open in the longitudinal direction. Observation of the fish meat 72AA and the fish meat 72AB that had been cut open vertically showed that the fish meat had a deep pink color, and no air bubbles were found.
On the other hand, when the fish sausage (B) obtained without using the dispersion member 40 is vertically split and opened, as shown in FIG. 73B, bubble 74A and bubble 74B were included. The bubble 73A and the bubble 73B, and the bubble 74A and the bubble 74B were integrated bubbles before the splitting. The fish meat 72A and the fish meat 72B had a lighter pink color than the fish sausage (A), probably because of the high air mixing rate.

As described above, the fish sausage (A) in which almost no air bubbles can be seen has a higher apparent specific gravity and a smaller variation in the detected specific gravity than the conventional fish sausage (B) containing air bubbles. , the oxidative deterioration of sausage ingredients could also be prevented. Therefore, it was able to greatly contribute to the stabilization of product quality.

As described above, according to the twin-screw pump 1 of this embodiment , the dispersing member 40 is arranged on the inlet side of the viscous fluid intake port 18 , so that the viscous fluid immediately before being taken into the pump casing 2 Q can be dispersed by a dispersion member 40 for flow restriction. As a result, the fluidization of the viscous fluid Q can be promoted, and the collision of the bubbles in the viscous fluid Q can be promoted to increase the diameter of the bubbles. Therefore, in the viscous fluid Q taken into the pump casing 2, the large-diameter bubbles easily move toward the gas extraction port 20, so that the high-viscosity fluid Q, in which the bubbles are originally difficult to move, is used. Even if there is, the air bubbles can be reliably and highly extracted from the viscous fluid Q, and the degassing performance can be improved. In addition, the function of the surface area increasing means 77 provided by the dispersing member 40 increases the surface area of the viscous fluid N, N, N, . be improved.

By the way, as shown in FIG. 10(a), each passage hole 41 of the dispersion member 40 has a relatively wide hole width Y (for example, 5 mm). However, it is possible to use a dispersing member having passage holes with a hole width corresponding to the viscosity and quality of the viscous fluid Q. FIG. For example, in the distribution member 40A of FIG. 10B, the hole width YA of each passage hole 41A is set to 4 mm. Further, the hole width YB of each passage hole 41B is 3 mm in the distribution member 40B of FIG. 4C, and the hole width YC of each passage hole 41C is 2 mm in the distribution member 40C of FIG. 4D. It goes without saying that these dispersing members 40A to 40C also exhibit the same kind of effects as the dispersing member 40 does.

In the distribution members 40 to 40C on the upper surface, a plurality of through holes 41 to 41C linearly viewed from the top are arranged in parallel , for example , as shown in FIGS. Distribution members 40a-40d are also helpful for the present invention. In these components, the distribution member 40a is formed with linear passage holes 41a arranged radially, and the distribution member 40b is formed with a large number of circular passage holes 41b. Further, in the distribution member 40c, a large number of circular passage holes 41c having a larger diameter than the passage holes 41b are formed, and in the distribution member 40d, a plurality of passage holes 41d having a large diameter are arranged in a cross shape. formed. Even with such a dispersing member, the viscous fluid Q can be fluidized and the collision between the bubbles can be promoted, so that the effect of improving the degassing can be obtained.

"Embodiment 1. "
In the above-described embodiment, the dispersion members 40 to 40C and 40a are provided with the plate-like main body 42 and the plurality of passage holes 41 to 41C and 41a to 41d formed in the plate-like main body 42, respectively. 40d are shown as a reference example, but for example , a twin-screw pump having a dispersing member 40e as shown in FIG. 12 is included in the present invention as the first embodiment .
The dispersing member 40e includes a disc-shaped plate-like body 45 that covers the viscous fluid intake 18 of the pump casing 2, a valve seat hole 38 that is formed through the plate-like body 45 from front to back, and a valve seat hole 38. To fix the valve body 46 at a predetermined position on the plate-like body 45, and the valve body 46 arranged with the passage gap YD (see FIG. 14) through which the viscous fluid can pass between the inner peripheral surface 37 and the plate-like body 45 , a fixing member 47 and a nut 59. Further, the dispersing member 40 e also has a gap variable mechanism 39 . The variable gap mechanism 39 includes a base portion 55 of the fixing member 47, a female screw portion 57 of the base portion 55, and a male screw portion 48 erected on the upper portion of the valve body 46 and screwed with the female screw portion 57. and consists of

As shown in FIG. 13(c), the plate-like body 45 is a disk-like body that covers the viscous fluid inlet 18, and has a stepped portion 44a that is recessed downward from the upper surface of the plate. , between the outer peripheral edge and the inner peripheral edge (upper edge of the inner peripheral surface 37 of the valve seat hole 38) of the circular valve seat hole 38 in plan view formed vertically through the central portion of the stepped portion 44a, and the stepped portion 44a. , and bolt insertion holes 43, 43, 43, 43 formed in the periphery of the plate.
As shown in FIG. 13(a), the valve body 46 is composed of a truncated conical tapered portion 49 whose diameter is reduced upward, and a male screw portion 48 erected on the upper surface of the tapered portion 49. It is Reference numeral 49A in the drawing denotes the lower surface of the tapered portion 49. As shown in FIG. The valve body 46 is manufactured as a whole by shaving, for example, a stainless steel bar.
As shown in FIG. 13(b), the fixing member 47 includes a flat plate-shaped base portion 55, a pair of legs 56, 56 vertically provided from both ends of the base portion 55, and the base portion 55. A female threaded portion 57 is formed at the center of the plane and screwed with the male threaded portion 48 of the valve body 46 . The lower ends of the legs 56 , 56 are formed with the same curvature as the mounting groove 58 of the plate-like body 45 so that they can be installed at any free position within the mounting groove 58 .

In the twin-screw pump using the dispersing member 40e configured as described above, as shown in FIG. It disperses by descending while spreading along 49 . After that, the viscous fluid Q passes through the passage gap 41 e having a gap width YD, for example, reaches the viscous fluid inlet 18 , and flows into the pump casing 2 . By disposing the dispersion member 40e in this manner, a passage gap YD for allowing the viscous fluid Q to pass is formed between the inner peripheral surface 37 of the valve seat hole 38 and the tapered portion 49 of the valve body 46. can be done. By allowing the viscous fluid Q to pass through the passage gap YD, the flow rate of the viscous fluid Q can be restricted and diverted like the inflow viscous fluid N1, and advanced degassing can be realized.

Furthermore, in the variable clearance mechanism 39 , the male threaded portion 48 of the valve body 46 is screwed up and down with respect to the female threaded portion 57 of the fixed member 47 . The gap width YD (size) of the passage gap 41e can be adjusted by moving the tapered portion 49 (outer peripheral surface) of the . Therefore, the gap width YD of the passage gap 41e can be changed to an appropriate size suitable for the viscosity of the viscous fluid Q. FIG. For example, for a viscous fluid Q having a higher viscosity, the male threaded portion 48 is screwed downward (in the direction of the arrow N in FIG. 14) with respect to the female threaded portion 57, so that the passage gap 41e is made, for example, the width of the gap. It can be expanded like YD1. Further, by bringing the tapered portion 49 of the valve body 46 into close contact with the inner peripheral surface 37 of the valve seat hole 38, the passage gap 41e can be completely closed. Furthermore, the dispersing member 40e also increases the surface area of the inflowing viscous fluid N1 compared to before the inflow, so that the defoaming performance can be further enhanced.

"Embodiment 2. "
In addition, in the first embodiment described above, the twin-screw pump having the dispersing member whose gap width is variable was exemplified, but the present invention is not limited thereto. For example, the present invention also includes a twin-screw pump using a fluid restriction member having a single passage hole. Such a twin-screw pump, as shown in FIGS. 15 to 19, has a fluid restriction member 78 instead of the dispersing member shown in the first embodiment. This fluid throttling member 78 is another example of the surface area increasing means 77, and has a ring-shaped plate-like main body 42 that covers the viscous fluid intake 18 of the pump casing 2, and the entire inner peripheral edge of the plate-like main body 42 from the upper surface of the plate. A stepped portion 44 formed by recessing downward, a bottomed cylindrical cylindrical body portion 79 vertically provided over the entire circumference of the inner peripheral edge of the stepped portion 44, and a bottom surface portion 80 of the cylindrical body portion 79 vertically penetrating. and bolt insertion holes 43 , 43 , 43 , 43 formed in the periphery of the plate-like main body 42 and through which the bolts 51 pass. The thickness t of the plate-like main body 42 is, for example, 10 mm. The cylindrical body portion 79 of the fluid throttle member 78 is inserted into the introduction passage 86 of the flange receiving portion 50, and the plate-like main body 42 is attached to the flange receiving portion together with the flange portion of the tube portion 21 by the bolt 51 passed through the bolt insertion hole 43. Fixed at 50. A top opening of the cylindrical body portion 79 serves as an introduction hole 83 for taking in the viscous fluid Q from the pipe portion 21 .

In this case, the opening area B1 of the ^single passage hole 82 (flow cross section area) [hole width SH×diameter L] is smaller. The bottom portions 80, 80 of the cylindrical body portion 79 are two concave curved surfaces corresponding to the ceiling shape of the pump chambers 6, 6 of the pump casing 2, and the ridgeline portion 81 where the bottom portions 80, 80 are joined extends forward and backward. It has a straight line shape. The passage hole 82 is formed so as to extend in the left-right direction perpendicular to the linear ridgeline portion 81 . The boundary portions of the left and right pump chambers 6, 6 are a ridgeline portion 84 on the ceiling side and a ridgeline portion 85 on the lower side, which extend in the front-rear direction within the pump casing 2. As shown in FIG.

Using the twin screw pump configured as described above, the viscous fluid Q "tororo (viscosity 8000 cp)" is introduced from the hopper 24 and degassed by the degassing device 27 while being transferred by the pump screws 7a and 7b. Then, the liquid was discharged from the viscous fluid discharge port 19 . The discharged grated yam was boiled in hot water, and the defoaming performance was evaluated by the ups and downs in the hot water. If there are many air bubbles in the tororo, the tororo after boiling will float in the hot water, and if there are few air bubbles, it will sink. In this case, the test grated yam showed a state of sinking after boiling, indicating that it was sufficiently degassed. Incidentally, it was found that the grated yam that had been transported by a twin-screw pump that did not use the fluid restricting member 78 floated after boiling, indicating that degassing was insufficient.

Subsequently, using a twin-screw pump using a fluid throttling member 78, "pasta sauce (viscosity 100,000 cp)", which is the viscous fluid Q, is introduced from the hopper 24 in the same manner as for grated yam, and degassing device 27 While degassing with , it was transferred by the pump screws 7 a and 7 b and discharged from the viscous fluid discharge port 19 . The defoaming performance was evaluated by measuring the apparent specific gravity of the discharged pasta sauce. In this case, many samples of the measured pasta sauce had an apparent specific gravity higher than the preset specific gravity for evaluation, and the defect rate was relatively small at 0.125%. Also, no pasta sauce was observed to enter the communication passage 29 leading to the degassing device 27 . On the other hand, the pasta sauce sample transported by the twin-screw pump without using the fluid throttle member 78 had an apparent specific gravity lower than the specific gravity for evaluation and a defective rate of 0.25%, and the pasta sauce A part of it entered the communication passage 29 to the degassing device 27 and foresaw the future failure of the degassing device 27 .

On the other hand, the fluid restricting member 78 was prepared so that the width SH of the passage hole 82 was 5 mm and 2 mm, and the viscous fluid Q was applied to the twin-screw pump using each of them. The defoaming performance was evaluated by an apparent specific gravity test. As a result, it was found that using the fluid restricting member 78 with a hole width SH of 2 mm was superior in defoaming performance to using the fluid restricting member 78 with a hole width SH=5 mm. However, when the fluid restricting member 78 with a hole width SH=2 mm is used, the amount of fluid passing through the passage hole 82 is inevitably reduced. only applicable.

As described above, since the twin-screw pump 1 of the third embodiment uses the fluid throttle member 78, the viscous fluid Q flowing into the viscous fluid intake port 18 passes through the passage hole of the fluid throttle member 78. The viscous fluid is narrowed by 82 to an open hole area smaller than the channel cross-sectional area A of the viscous fluid intake 18 and sent. Therefore, as shown in FIG. 16, the surface area (peripheral area [2·(L+SH)·J2]) of the inflowing viscous fluid N2 (unit volume corresponding to the inflow length J2) that has passed through the passage hole 82 per unit time is It is larger than the surface area (peripheral area [L·π·J]) of the inflowing viscous fluid N (unit volume of inflow length J) flowing through the viscous fluid intake 18 per unit time. As a result, a large amount of degassing can be performed from the inflowing viscous fluid N2.

Further, since the fluid throttling member 78 includes the plate-shaped main body 42, the cylindrical body portion 79, and the passage hole 82 of the cylindrical body portion bottom surface portion 80, the structure is simple and inexpensive, and the viscous fluid can pass through the hole. The surface area of the inflowing viscous fluid N2 that has been throttled at 82 can be increased, and high degree of degassing can be performed. The passage hole 82 of the cylindrical body portion 79 is arranged so that the longitudinal direction of the slit (the direction of arrow V ( see FIG. 17 )) is directed to the right and left directions perpendicular to the axes Xa and Xb of the pump casing 2. Therefore, the distance from any position of the slit of the passage hole 82 to the gas extraction port 20 is substantially the same. Therefore, the inflowing viscous fluid N2 can be efficiently degassed regardless of the passage position in the passage hole 82 .

"Embodiment 3. "
In the above description, the twin-screw pump using the fluid restricting member 78 having the slit-like passing hole 82 with the narrow hole width SH as an example of the surface area increasing means 77 is shown, but the present invention is not limited thereto. For example, the present invention also includes a twin-screw pump using a fluid throttle member 78a as shown in FIG. The fluid throttle member 78a of the third embodiment also has the same components as the fluid throttle member 78 of the second embodiment. 2 is attached. The fluid throttling member 78a is made flat by leaving the bottom surface portions 80a, 80a on the front side (discharge port side) of the cylindrical body portion 79 and cutting out the rear side (air vent side) of the bottom surface portion. A passage hole 82a having a semicircular shape and a wide hole width SH1 is formed.
In the twin-screw pump using this fluid restricting member 78a, the inflowing viscous fluid N having an inflow length J per unit time flowing from the viscous fluid inlet 18 into the introduction hole 83a of the fluid restricting member 78a is , is narrowed down to an opening area smaller than the channel cross-sectional area A of the introduction hole 83a. That is, the surface area (peripheral area) of the inflowing viscous fluid N3 (fluid amount corresponding to the inflow length J3) that has passed through the passage hole 82a is equal to the inflowing viscous fluid N (fluid amount corresponding to the inflow length J3) flowing through the introduction hole 83a per unit time. ) surface area (peripheral area). As a result, a large amount of air was removed from the inflowing viscous fluid N3.

The present invention described above is not limited to the first to third embodiments described above. Of course, the present invention includes any design changes that do not deviate from the gist of the invention.

1 twin screw pump 2 pump casing 2A inner peripheral surfaces 7a, 7b pump screws 7Sa, 7Sb side surface 7B tip surfaces 8a, 8b shaft portion 18 viscous fluid intake port 19 viscous fluid discharge port 20 gas extraction port 27 degassing device 29 communication passage 37 inner peripheral surface 38 valve seat hole 39 gap variable mechanism
40e dispersion member
41e passage gap 42 plate-like body 45 plate-like body 46 valve body 47 fixing member 48 male screw portion 49 tapered portion (outer peripheral surface)
50 Flange receiving portion 57 Female screw portion 59 Nut 77 Surface area increasing means 78 Fluid restriction member 79 Cylindrical portion 80 Bottom portion 82 Passing holes G, H Gap Q Viscous fluids Xa, Xb Axial center
SH, SH1 Hole width YD, YD1 Gap width J , J2 , J3 Inflow length L Diameter N, N1, N2, N3 Inflow viscous fluid

Claims (4)

a pair of pump screws that are screwed together and driven to rotate in a non-contact manner; a cylindrical pump casing that accommodates the pair of pump screws in a non-contact manner; A viscous fluid intake port, a viscous fluid discharge port provided on the tip end side of the pump casing, a gas discharge port provided on the upper surface of the pump casing more distal than the viscous fluid intake port, and the gas discharge port. and a degassing device connected to a gas-permeable and viscous A twin-screw pump in which a fluid-impermeable gap is formed,
The viscous fluid inlet of the pump casing is provided with a surface area increasing means for increasing the surface area per unit volume of the viscous fluid and allowing it to flow into the pump casing ,
wherein the surface area increasing means comprises a dispersing member that diverts the viscous fluid into the pump casing to limit the flow rate of the viscous fluid taken in from the viscous fluid inlet;
The dispersing member includes a plate-like body that covers the viscous fluid intake, a valve seat hole formed through the plate-like body from front to back, and an inner peripheral surface of the valve seat hole. and a fixing member for fixing the valve body to the plate-like body. After the viscous fluid passes through the passage gap, A twin-screw pump characterized in that it is constructed such that it flows into the pump casing at the same time . 2. The valve assembly according to claim 1 , further comprising a gap variable mechanism that changes the size of the passage gap by moving the outer peripheral surface of the valve body closer to and away from the inner peripheral surface of the valve seat hole. Twin screw pump. a pair of pump screws that are screwed together and driven to rotate in a non-contact manner; a cylindrical pump casing that accommodates the pair of pump screws in a non-contact manner; A viscous fluid intake port, a viscous fluid discharge port provided on the tip end side of the pump casing, a gas discharge port provided on the upper surface of the pump casing more distal than the viscous fluid intake port, and the gas discharge port. and a degassing device connected to a gas-permeable and viscous A twin-screw pump in which a fluid-impermeable gap is formed,
The viscous fluid inlet of the pump casing is provided with a surface area increasing means for increasing the surface area per unit volume of the viscous fluid and allowing it to flow into the pump casing,
The surface area increasing means restricts the viscous fluid taken in from the viscous fluid intake to a flow passage cross-sectional area smaller than that of the viscous fluid intake, and then flows into the pump casing. is composed of
The fluid throttling member comprises a ring-shaped plate-shaped body covering the viscous fluid inlet, a bottomed tubular body vertically provided on the inner peripheral edge of the plate-shaped body, and a bottom surface of the tubular body. a passage hole having an open hole area smaller than the flow passage cross-sectional area of the cylindrical body portion, the viscous fluid in the cylindrical body portion passing through the passage hole. A twin-screw pump characterized in that it is configured to flow into the pump casing afterward. The passage hole of the cylindrical body portion is formed in a slit shape, and the passage hole is arranged such that the longitudinal direction of the slit is aligned with the axis of the pump casing when the fluid throttle member is arranged in the viscous fluid intake port. 4. A twin-screw pump according to claim 3 , characterized in that it is arranged in a perpendicular direction.

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