TW201410976A - Bellows pump - Google Patents

Abstract

The present invention provides a bellows pump that prevents deformation of a bottom wall resulting from pressure variation of a pumping chamber and provides having a pumping function of stabilization of liquid amount of conveyance and circulation. The bellows pump of the present invention is constructed as follows: a plastic bellows tube (6) is arranged in an extendable/retractable manner in an axial direction so as to alternately perform a discharging operation of supplying a liquid from a pumping chamber (7) formed by being surrounded by the bellows tube (6) and an intake operation of supplying the liquid to the pump chamber (7). In the bellows pump, a metal operation plate (10) is supported by the pump housing (5) in a manner of being movable in the axial direction and the operation sheet (10) and a bottom wall (6c) of the bellows tube (6) are secured to each other in outer circumferential portions thereof so that opposing end faces (6g, 10c) of a central part of the bottom wall (6c) of the bellows tube (6) that is a liquid contacting part (6f) in contact with the liquid in the pumping chamber (7) and the operation plate (10) are in tight engagement with each other. The parts (6g,10c) that are in tight engagement with each other are sealed by a sealing element of an O-ring (15).

Description

Telescopic pump

The present invention relates to a slurry for use in a chemical solution (for example, a chemical solution used in a semiconductor, a liquid crystal, an organic EL, or the like) or a slurry component such as a solid component (for example, using a CMP apparatus (CMP) A telescopic pump that feeds liquid and circulates a liquid such as a polishing liquid used in a surface polishing apparatus for a semiconductor wafer of the method of the invention.

As such a telescopic pump, it is known that a plastic bottomed cylindrical telescopic tube having an opening attached to a pump casing is stretched and contracted in the axial direction, thereby being alternately formed by being surrounded by a telescopic tube. The pumping chamber discharges the liquid to the discharge passage through the discharge-side check valve, and the suction step of supplying the liquid to the pump chamber through the suction-side check valve from the suction passage (see, for example, FIG. 1 or Patent Document 2 of Patent Document 1) figure 2).

In the telescopic pump, there is a problem that the bottom of the plastic telescopic tube is deformed due to pressurization of the pump chamber during the discharge step and/or decompression (negative pressure) of the pump chamber during the suction step. . For example, when the telescopic tube is subjected to the discharge step of the reduction operation, the bottom wall of the telescopic tube is convexly bent by the pressure of the pump chamber, and conversely, when the extension tube is subjected to the suction step of the stretching operation, due to the pump chamber It is a negative pressure, so there is a problem that the bottom wall of the bellows is attracted to be concavely curved. Alternatively, when the mechanism for causing the telescopic tube to perform the telescopic operation is a cylinder mechanism (refer to paragraph number [0024]), there is a pressurized air supplied to the supply and exhaust space, so that the plastic is made. The bottom wall of the telescopic tube has a problem of deformation such as bending. For example, in the discharge step of the telescopic tube performing the reduction operation, when the pressure of the supply and exhaust space is smaller than the pressure of the pump chamber, there is a pressurized air supplied to the supply and exhaust space, so that the bottom wall of the extension tube is pushed. The pressure is bent into a concave shape toward the pump chamber. Therefore, if the bottom wall of the bellows is deformed in this manner, the amount of liquid to be supplied (the amount of discharge liquid) or the amount of circulating fluid of the telescopic pump may be unstable, and variations may occur, and an appropriate pump function may not be exerted.

[Advanced technical literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2002-174180

[Patent Document 2] Japanese Laid-Open Patent Publication No. 2012-122380

In the telescopic pump, since the pump chamber is pressurized in the discharge step and/or the pump chamber is depressurized (negative pressure) in the suction step, the bottom wall of the plastic telescopic tube is deformed by bending or the like. problem. For example, in the discharge step in which the telescopic tube is subjected to the reduction operation, there is a problem that the bottom wall of the telescopic tube is pressed and convexly curved due to the pressure of the pump chamber, and conversely, in the suction step of the extension operation of the extension tube The pump chamber is under negative pressure, so there is a problem that the bottom wall of the bellows is attracted and bent into a concave shape. Therefore, if the bottom wall of the bellows is deformed in this way, the volume of the pump chamber is substantially changed, and the liquid supply amount (the amount of the discharge liquid) or the circulating fluid amount of the telescopic pump is unstable, and variations occur, etc., which cannot be properly performed. Pump function.

However, in the telescopic pump, as shown in FIG. 1 of Patent Document 1 and Patent Document 2 2, as a mechanism for guiding the movement of the telescopic tube in the axial direction (the expansion and contraction operation) or as a mechanism for synchronizing the expansion and contraction movements of the two telescopic tubes in the double-acting type telescopic pump, the bottom wall of the telescopic tube is connected An actuating plate supported by the pump casing that is movably movable in the axial direction. Therefore, by making the actuating plate made of metal, the bottom wall of the telescopic tube which is easily deformed by plastic can be reinforced.

However, the connection between the bottom wall of the bellows and the actuating plate is as shown in FIG. 1 of Patent Document 1 or FIG. 2 of the patent document, and since it is performed only on the outer peripheral portion thereof, the central portion of the bottom wall of the telescopic tube is The portion that is not connected to the actuation plate cannot be prevented from being deformed by the pressure fluctuation of the pump chamber in the above-described discharge step and/or suction step. For example, if the pump chamber is under negative pressure in the suction step, the central portion of the bottom wall of the telescopic tube that is not fixed to the actuation plate is bulged into the pump chamber due to the attraction force generated by the negative pressure (deformed into a concave shape). Problem)

The present invention has been made in view of the above, and it is an object of the invention to provide a method for reliably preventing deformation of a bottom wall of a bellows due to a pressure fluctuation of a pump chamber during a discharge step and/or a suction step, and the amount of liquid to be supplied (The amount of the discharge liquid) or the amount of the circulating fluid does not cause a deviation, and the telescopic pump that can stably and appropriately function as a pump can be used.

The present invention relates to a telescopic pump which is configured such that a plastic bottomed cylindrical telescopic tube having an opening attached to a pump casing is stretched and contracted in an axial direction, thereby being alternately formed by being surrounded by a telescopic tube. The pumping chamber discharges the liquid to the discharge passage through the discharge-side check valve, and the suction step of supplying the liquid to the pump chamber through the suction-side check valve from the suction passage, and in order to achieve the above object, (1) or 2) General composition.

(1) The metal base plate and the bottom wall of the bellows are connected and fixed to the outer peripheral portion thereof, and the metal plate is supported by the pump casing so as to be movable in the axial direction. The central portion of the bottom wall of the shrink tube, that is, the liquid contact portion in contact with the liquid of the pump chamber is in close contact with the opposite end surface of the actuation plate, and the close portion is sealed by an annular sealing member.

(2) The metal base plate and the bottom wall of the bellows are connected and fixed to the outer peripheral portion thereof, and the metal plate is supported by the pump casing so as to be movable in the axial direction so that the center of the bottom wall of the bellows is A portion of the liquid contact portion that is in contact with the liquid of the pump chamber and the opposite end surface of the actuating plate are formed with a sealed space sealed by the annular sealing member, and the sealed space is filled with an incompressible fluid.

In a preferred embodiment of the telescopic pump, the annular sealing member is an O-ring, and the O-ring is engaged and held in an O-ring groove formed in a bottom wall of the telescopic tube or an actuating plate.

In the case of the telescopic pump of the present invention, in the case of the configuration of (1), since the central portion of the bottom wall of the bellows, that is, the liquid-contacting portion, is in close contact with the actuation plate in a sealed state, the pressure of the pump chamber varies. In any case, the liquid-contacting portion and the actuating plate are always kept in an inseparable manner, and in the case of the configuration as in (2), the liquid-contacting portion and the central portion of the bottom wall of the bellows are actuated. The sealed space formed between the plates is filled with a non-compressible fluid, and the sealed space filled with the non-compressible fluid functions as a rigid body, so the liquid-contacting portion can always be used regardless of the pressure fluctuation of the pump chamber. The sealed space in which the rigid body functions and the actuating plate are kept in a state in which they are inseparably in close contact with each other. Therefore, in any one of (1) and (2), for the pressure of the pump chamber, the metal plate is used to reinforce the liquid contact portion of the bottom wall of the bellows, and the pressure due to the pump chamber can be reliably prevented. The deformation of the wetted portion caused by the change. Alternatively, in the telescopic pump of the present invention, when the mechanism for causing the telescopic tube to perform the expansion and contraction operation is a cylinder mechanism (see paragraph number [0024]), the telescopic tube is prevented from being subjected to the expansion and contraction operation. The pressurized air supplied to the supply and exhaust space enters between the bottom wall of the plastic telescopic tube and the metal-made moving plate, and can reliably prevent the plastic telescopic tube caused by the pressurized air supplied to the supply and exhaust space. Deformation of the bottom wall. Therefore, in the suction step and the discharge step, the volume of the pump chamber does not change due to deformation of the bottom wall of the bellows, and the amount of liquid to be delivered (the amount of discharge liquid) or the amount of circulating fluid is stable, and an appropriate pump can be exerted. Features. Further, since the bottom wall of the bellows itself does not need to have the strength to prevent deformation due to the pressure fluctuation of the pump chamber, whether it is constituted as in (2) or in the case of (1), It can be as thin as possible, so that the telescopic tube can be greatly reduced in weight.

1‧‧‧ spitting pathway

2‧‧‧Inhalation pathway

3‧‧‧ pump head

4‧‧‧Cylinder shell

4a‧‧‧Exhaust port

4b‧‧‧Air supply space

4c‧‧‧ pressurized air

4d‧‧‧air supply space

5‧‧‧ pump casing

6‧‧‧ telescopic tube

6a‧‧‧Walls

6b‧‧‧Open end

6c‧‧‧ bottom wall

6d‧‧‧ End of the valley

6e‧‧‧outer part

6f‧‧‧ wetted parts

6g‧‧‧ opposite end faces

6h‧‧‧ positioning convex

7‧‧‧ pump room

8‧‧‧Spread side check valve

8a‧‧ ‧ spring

8b‧‧‧ valve body

9‧‧‧Inhalation side check valve

9a‧‧ ‧ spring

9b‧‧‧ valve body

10‧‧‧ actuation board

10a‧‧‧ Body Department

10b‧‧‧Linking Department

10c‧‧‧ opposite end faces

10d‧‧‧Circular recess

10e‧‧‧outer part

10f‧‧‧ female thread recess

11‧‧‧Installation board

12‧‧‧ Connecting rod

12a‧‧‧End screws

13‧‧‧O-ring

14‧‧‧ Nut components

15‧‧‧Aperture sealing member (O-ring)

15a‧‧O ring groove

15b‧‧‧O ring groove

16‧‧‧ screws

17‧‧‧Installation board

18‧‧O ring

19‧‧‧ bearing ring

20‧‧‧ actuation axis

20a‧‧‧Threading Department

21‧‧‧Link board

22‧‧‧Seal space

23‧‧‧Incompressible fluid

24‧‧O ring

Fig. 1 is a longitudinal sectional side view showing an example of a telescopic pump of the present invention.

Fig. 2 is a longitudinal sectional front view of a main portion taken along line II-II of Fig. 1.

Fig. 3 is a longitudinal sectional side view showing a modification of the telescopic pump of the present invention.

Fig. 4 is an enlarged view of a main part of Fig. 3.

Fig. 5 is a longitudinal sectional front view taken along line V-V of Fig. 3.

Fig. 6 is a longitudinal sectional side view showing another modification of the telescopic pump of the present invention.

Fig. 7 is an enlarged view of a main part of Fig. 6.

Fig. 8 is a longitudinal sectional front view taken along line VIII-VIII of Fig. 6.

The form for carrying out the invention will be specifically described based on the drawings.

Fig. 1 is a longitudinal sectional side view showing an example of a telescopic pump of the present invention, and Fig. 2 is a longitudinal sectional front view of a main portion taken along line II-II of Fig. 1. Furthermore, in the following description, left and right Refers to the left and right in Figure 1.

The telescopic pump (hereinafter referred to as "first pump") shown in FIG. 1 is used for liquid supply and circulation of a liquid (for example, a chemical liquid used in a manufacturing process such as a semiconductor, a liquid crystal, or an organic EL). The horizontal double-acting type telescopic pump is configured to include a pump casing 5 including a pump head 3 having a discharge passage 1 and a suction passage 2, and a pair of left and right cylinder casings 4 provided on both sides thereof. A pair of left and right telescopic tubes 6 are disposed in each of the cylinder casings 4, and are attached to the pump head 3 in a linear direction (horizontal direction), and a pair of left and right pump chambers 7 surrounded by the respective telescopic tubes 6. A pair of right and left discharge check valves 8 are attached to the pump head 3 in a state of protruding toward the respective pump chambers 7; and a pair of left and right suction side check valves 9 are attached to the respective pump chambers 7 In the pump head 3, the two telescopic tubes 6 are alternately expanded and contracted, and the discharge step of supplying liquid from the pump chamber 7 to the discharge passage 1 through the discharge side check valve 8 and the self-suction passage 2 are simultaneously performed. A suction step of supplying liquid to the other pump chamber 7 via the suction side check valve 9. Further, the two cylinder cases 4, the two bellows 6, the two pump chambers 7, the two discharge side check valves 8, and the two suction side check valves 9 constituting the telescopic pump are the same except for the left-right symmetrical structure. structure.

The pump head 3 has a disk shape in which the discharge passage 1 connected to the liquid supply line and the suction passage 2 connected to the liquid supply line are formed. Therefore, as shown in Fig. 1, the left and right sides are respectively branched and opened. The upstream end of the passage 1 and the downstream end of the suction passage 2.

Each of the cylinder casings 4 has a bottomed cylindrical shape attached to the pump head 3 as shown in Figs. 1 to 4 . The pump casing 5 is constituted by the two cylinder casings 4 and the pump head 3, and is divided into two left and right portions by the pump head 3 inside the pump casing 5.

As shown in FIG. 1 and FIG. 2, each of the bellows 6 has a peripherally formed cylindrical body having a cross-sectional wave-shaped serpentine structure, and is expanded by the axial direction (left-right horizontal direction). The volume of the pump chamber 7 is reduced. Each of the bellows 6 has its open end 6b closely attached to the pump head 3, and the inside of the bellows 6 is configured as a pump chamber 7 that is closed by the pump head 3. As a constituent material of each of the bellows 6, a fluororesin (for example, polytetrafluoroethylene (PTFE), perfluoroalkoxy resin (PFA)) or the like can be used depending on the properties of the liquid, etc., but in this case, PTFE is used. . In each of the bellows 6, the bottom wall 6c is a disk having a constant wall thickness (thickness in the axial direction), and the outer diameter thereof is the same as the outer diameter of the peripheral wall 6a (the outer diameter of the mountain portion), and the valley of the peripheral wall 6a. The end portion 6d of the portion is coupled to the bottom wall 6c.

As shown in FIG. 1, the bottom wall 6c of each bellows 6 is connected and fixed to a disc-shaped actuating plate 10 made of metal (for example, stainless steel). Each of the actuating plates 10 is composed of a thin-walled disk-shaped main body portion 10a and a thick-walled annular connecting portion 10b formed on the outer peripheral portion thereof, and is joined to and bonded to the main body portion 10a of the actuating plate 10, and is fitted to The state of the connecting portion 10b is connected and fixed to the bottom wall 6c of the bellows 6. That is, the wall thickness of the bottom wall 6c of the bellows 6 is set to be the same as or slightly thicker than the wall thickness (thickness in the axial direction) of the joint portion 10b of the actuating plate 10, by being attached to the joint portion 10b of the actuating plate 10. The outer peripheral portion of the bottom wall 6c of the bellows 6 is pressed between the mounting plate 11 and the main body portion 10a of the actuating plate 10 (the outer peripheral side of the bottom wall 6c is closer to the connecting portion of the end portion 6d of the valley portion of the peripheral wall 6a). Part 6), as shown in FIG. 1, the bottom wall 6c of the bellows 6 is connected to the outer peripheral portion of the actuating plate 10 in a state in which the bottom wall 6c of the bellows 6 is in close contact with the body portion 10a of the actuating plate 10. And integration.

The two telescopic tubes 6 are connected to the movable plate 10 by a plurality of (for example, four) connecting rods 12, and simultaneously expand and contract in the opposite direction. That is, as shown in FIG. 1 , when one telescopic tube 6 is in the most reduced state, the other telescopic tube 6 is in the most extended state, and the two telescopic tubes 6 are connected in series, that is, when the telescopic tube 6 performs the reduction operation. The other telescopic tube 6 is extended in conjunction with it.

In the plurality of connecting rods 12, the outer peripheral portions of the two actuating plates 10, that is, the connecting portions 10b are connected at equal intervals in the circumferential direction, and the two actuating plates 10 are coupled by the connecting rods 12, and At the same time, the bottom wall 6c of each of the bellows 6 is connected to the actuating plate 10 at the same time. In other words, each of the connecting rods 12 is disposed in the cylinder casing 4 and is inserted into and held in the pump casing 5 via the O-ring 13 so as to be movable in the axial direction, and penetrates the end portion of the connecting portion 10b of the mounting plate 11 and the actuating plate 10 The screw 12a is screwed to the nut member 14 and fastened, thereby connecting the two actuating plates 10, and connecting and fixing the bottom wall 6c of each of the bellows 6 and the actuating plate 10. Further, the wall thickness of the main body portion 10a of the actuating plate 10 is set to have at least an intensity that does not cause deformation due to the pressure of the pump chamber 7 in the suction step and the discharge step, and preferably has the same Set as thin as possible within the range of strength.

The operation mechanism for causing the telescopic tube 6 to perform the expansion and contraction operation is generally constituted by a piston-cylinder mechanism, a crank mechanism, an air cylinder mechanism, etc., but in this example, it is constituted by an air cylinder mechanism. In other words, the operating mechanism is configured such that the air supply and exhaust port 4a formed in the bottom wall of each of the cylinder casings 4 is supplied to the air supply and exhaust space 4b formed between the bellows 6 and the actuating plate 10 and the cylinder casing 4 The air (4c) is pressurized, whereby the telescopic tube 6 is expanded and contracted in the axial direction. The supply and exhaust from the two supply and exhaust ports 4a are alternately and simultaneously performed, and are simultaneously exhausted from the other supply and exhaust port 4a by supplying the pressurized air 4c from the supply and exhaust port 4a to the supply and exhaust space 4b. The expansion and contraction operation of the two telescopic tubes 6 is the simultaneous expansion and contraction of the two pump chambers 7 in the opposite direction. That is, the suction step (or the discharge step) in one pump chamber 7 is performed in synchronization with the discharge step (or the suction step) in the other pump chamber 7, and the discharge step in the two pump chambers 7 (the liquid is discharged from the pump chamber 7 via the discharge) The step of the side check valve 8 supplying the liquid to the discharge passage 1 is performed simultaneously with the switching of the suction step (the step of supplying the liquid from the suction passage 2 to the pump chamber 7 via the suction side check valve 9). Furthermore, Fig. 1 shows the suction step in the pump chamber 7 on the left side. The end state of the discharge step in the pump chamber 7 on the right side.

As shown in Fig. 1, each of the discharge-side check valves 8 is configured such that when the extension tube 6 is extended (the volume of the pump chamber 7 is expanded and changed), the suction step is performed by the biasing force of the spring 8a. The valve body 8b is held at the valve closing position, and when the telescopic tube 6 performs the reduction operation (the volume of the pump chamber 7 is reduced and changed), the pressure is increased by the pump chamber 7, and the valve is biased against the biasing force of the spring 8a. The body 8b is moved to the valve opening position. As shown in Fig. 1, each of the suction side check valves 9 is configured such that in the discharge step of performing the reduction operation of the extension tube 6, the back pressure (pressure of the pump chamber 7) and the biasing force of the spring 9a are made. The valve body 9b is held at the valve closing position, and in the suction step in which the extension tube 6 is extended, the pressure of the pump chamber 7 is lowered, and the valve body 9b is moved to the valve opening position against the biasing force of the spring 9a.

Further, in the member which is in contact with the liquid among the pump constituent members such as the pump head and the bellows 6, the appropriate material can be selected according to the properties of the liquid or the like, and in this example, the corrosion resistance and the chemical resistance are selected. It is composed of a fluororesin-based plastic such as polytetrafluoroethylene.

Further, in the first pump, as shown in Fig. 1, the central portion of the bottom wall 6c of the bellows 6, that is, the liquid contact portion with the liquid of the pump chamber 7 (the bottom portion of the bottom wall 6c and the valley portion of the peripheral wall 6a) The portion on the inner peripheral side of the joint portion 6d) 6f is in close contact with the opposite end faces 6g and 10c of the actuating plate 10, and the close-contact portions 6g and 10c are sealed by the annular seal member 15. In this example, an O-ring composed of an incompressible inert material (such as fluororubber) is used as the annular seal member 15, and the O-ring 15 is engaged and held in the bottom wall 6c formed in the bellows 6 Ring groove 15a.

Therefore, when the pressure of the pump chamber 7 changes with the expansion and contraction operation of the bellows 6 (the expansion and contraction of the pump chamber volume), the bottom wall 6c of the bellows 6 does not deform, and does not The problem described at the outset is generated so that the proper pump function can be achieved.

That is, in the pump chamber (for example, the pump chamber on the left side shown in FIG. 1) in the suction step, the pressure in the pump chamber 7 is reduced due to the suction step by the stretching operation of the bellows 6 Negative pressure, therefore, only the bottom wall 6c of the bellows 6 to which the outer peripheral portion 6e is coupled to the actuating plate 10 has a problem that the central portion thereof, that is, the liquid-collecting portion 6f, is pulled in the pump chamber 7 of the negative pressure to be concavely curved and deformed. . However, the liquid-receiving portion 6f of the bottom wall 6c of the bellows 6 is in close contact with the body portion 10a of the actuating plate 10, and the close-contact portions 6g, 10c are sealed by the O-ring 15 so that it is not formed by the above-mentioned negative pressure. The body portion 10a of the movable panel 10 is separated from the attraction. In other words, the liquid contact portion 6f of the bottom wall 6c of the bellows 6 is held in a state in which it cannot be separated from the main body portion 10a of the actuator plate 10. Therefore, the suction force acting on the liquid contact portion 6f of the bottom wall 6c of the bellows 6 is received by the body portion 10a of the metal-made moving plate 10 without the problem that the liquid-repellent portion 6f is deformed at the suction step.

Further, in the pump chamber (for example, the pump chamber on the right side shown in FIG. 1) in the discharge step, the pressure of the pump chamber 7 rises due to the discharge step by the reduction operation of the bellows 6 Since the high pressure is applied, only the bottom wall 6c of the bellows 6 to which the outer peripheral portion 6e is coupled to the actuating plate 10 has a problem that the central portion, that is, the liquid receiving portion 6f, is convexly bent and deformed by the pressing force formed by the pressure of the pump chamber 7. However, since the liquid receiving portion 6f of the bottom wall 6c of the bellows 6 is in close contact with the body portion 10a of the actuating plate 10, the above-mentioned pressing force acting on the liquid receiving portion 6f is received by the body portion 10a of the metal making moving plate 10 There is no problem that the liquid receiving portion 6f is deformed at the time of the discharge step.

Thus, by the first pump, in any of the steps of the suction step and the discharge step, the bottom wall 6c of the bellows 6 is not deformed due to the pressure of the pump chamber 7, and the pump chamber is not generated. Substantial change in volume resulting in liquid delivery (discharge volume) or circulating fluid The amount is unstable, and there are problems such as deviations, so that appropriate pump functions can be exerted.

Further, in the first pump, since the liquid receiving portion 6f of the bottom wall 6c of the bellows 6 is reinforced by the actuating plate 10 as described above, the bottom wall 6c of the bellows 6 need not be provided with the pump chamber. The thicker person of the pressure of 7 with respect to the strength of the resistance is necessary and sufficient to be connected to the actuating plate 10 by the end plate screw 12a of the connecting plate 11 and the connecting rod 12 and the nut member 14. It is enough. Therefore, the bottom wall 6c of the bellows 6 can be made as thin as possible as compared with the conventional telescopic pump described at the outset, so that the weight of the bellows 6 can be reduced.

However, the configuration of the telescopic pump of the present invention is not limited to the above-described embodiments, and various modifications and changes can be made without departing from the basic principles of the invention.

For example, in the first pump, as shown in FIG. 1, the two actuating plates 10 are coupled to each other by a connecting rod 12 supported by the pump casing 5 so as to be movable in the axial direction, so that the actuating plates 10 are connected via the connecting rods. 12 is supported by the pump casing 5 so as to be movable in the axial direction, and the movable plate 10 and the bottom wall 6c of the bellows 6 are connected via the mounting plate 11 by connecting the movable plates 10 and the connecting rod 12, but each The supporting mechanism of the actuating plate 10 to the pump casing 5 and the connecting mechanism between each of the actuating plates 10 and the bottom wall 6c of the bellows 6 may be individually independent as shown in FIGS. 3 to 5.

3 is a longitudinal sectional side view showing a modification of the telescopic pump of the present invention, FIG. 4 is an enlarged view of a main portion of FIG. 3, and FIG. 5 is a longitudinal sectional front view taken along line VV of FIG. The telescopic pump (hereinafter referred to as "second pump") shown is a lateral double-acting type telescopic pump, which has the same configuration as that of the first pump except for the following points. In addition, the same components as those of the first pump are denoted by the same reference numerals as those in FIGS. 1 and 2 in FIGS. 3 to 5, and detailed description thereof will be omitted.

In the second pump, as shown in FIGS. 3 and 4, the bottom wall 6c of each of the bellows 6 and the actuating plate 10 are in the shape of a disk having the same thickness (thickness in the axial direction) of the same diameter, and The bottom wall 6c of the bellows 6 and the actuating plate 10 are connected in a state in which a plurality of screws 16 inserted into the outer peripheral portions 6e and 10e are screwed and fastened to the mounting plate 17 to be in close contact with each other. In this example, as shown in Fig. 5, the outer peripheral portion 6e of the bottom wall 6c of the bellows 6 and the outer peripheral portion 10e of the actuating plate 10 are connected by eight screws 16 arranged at equal intervals in the circumferential direction. . Further, the thickness of the actuating plate 10 is set to have at least a degree of deformation which is not deformed by the pressure of the pump chamber 7 in the suctioning step and the discharging step, and is preferably set as much as possible within the range having the strength. Thinner.

In the center portion of each of the actuating plates 10, an operating shaft 20 movably supported in the axial direction is integrally formed on the bottom wall of the cylinder casing 4 via the O-ring 18 and the bearing ring 19. At the end of each of the actuating shafts 20, a disc-shaped connecting plate 21 is fixed to the outside of the cylinder casing 4, and the two connecting plates 21 are disposed outside the cylinder casing 4 and are suitably supported by the pump casing 5 by the axial direction. The connecting rods 12 of the number of roots (two in this example) are connected. Therefore, since the two actuating plates 10 are coupled via the actuating shaft 20, the connecting plate 21, and the connecting rod 12, the two telescopic tubes 6 can simultaneously expand and contract in the opposite direction. That is, as illustrated in FIG. 3, when one telescopic tube 6 is in the most reduced state, the other telescopic tube 6 is connected to the two telescopic tubes 6 in a state of being the most extended state, and when one telescopic tube 6 performs a reduction operation, the other The bellows 6 is extended in conjunction with it.

In the same manner as the first pump, the operation mechanism for causing the telescopic tube 6 to perform the expansion and contraction operation is configured such that an air supply port (not shown) formed in the bottom wall of each of the cylinder casings 4 is formed in the extension tube 6 and The supply and exhaust space 4d between the actuator plate 10 and the cylinder casing 4 is supplied with pressurized air, whereby the telescopic tube 6 is expanded and contracted in the axial direction. Further, the supply and exhaust of the two supply and exhaust spaces 4d are alternately and simultaneously performed, whereby the expansion and contraction operation of the two telescopic tubes 6, that is, the expansion and contraction operation of the two pump chambers 7, is performed in the opposite direction. That is, the suction step (or the discharge step) in a pump chamber 7 is The discharge step (or the suction step) in the other pump chamber 7 is performed simultaneously, and the discharge step in the two pump chambers 7 can be simultaneously performed (the liquid is supplied from the pump chamber 7 to the discharge passage 1 via the discharge-side check valve 8). The step is switched with the suction step (the step of supplying the liquid from the suction passage 2 to the pump chamber 7 via the suction side check valve 9). Further, Fig. 3 shows the end state of the suction step in the pump chamber 7 on the left side and the discharge step in the pump chamber 7 on the right side.

Further, in the second pump, as shown in Figs. 3 and 4, in the same manner as the first pump, the central portion of the bottom wall 6c of the bellows 6, that is, the liquid contact portion with the liquid of the pump chamber 7 (bottom wall) The portion of the 6c which is closer to the inner peripheral side than the joint portion of the end portion 6d of the valley portion of the peripheral wall 6a) 6f is in close contact with the opposite end faces 6g, 10c of the actuating plate 10, and is sealed by the annular sealing member 15. The close portions 6g, 10c. In this example, as the annular seal member 15, an O-ring composed of an incompressible bismuth material (such as fluororubber) is used in the same manner as the first pump, and the O-ring 15 is engaged and held in the actuating plate. 10 O ring groove 15b. Further, in a central portion of the liquid contact portion 6f of the bottom wall 6c of the bellows 6, a circular positioning convex portion 6h closely fitted to the circular concave portion 10d formed at the central portion of the actuation plate 10 is formed, and The bottom wall 6c of the bellows 6 is designed to be concentrically joined to the actuating plate 10.

Therefore, in the second pump, similarly to the first pump, when the pressure of the pump chamber 7 changes as the telescopic tube 6 expands and contracts (the pump chamber volume expands and contracts), the bellows The bottom wall 6c of the 6 is also reinforced by the metal making of the movable plate 10, and is not deformed, so that the problem described at the beginning is not caused, and an appropriate pump function can be exerted. Further, in the second pump, since the connecting rod 12 is disposed outside the cylinder casing 4, the volume of the supply and exhaust space 4d is smaller than the supply and exhaust space 4b of the first pump, and the expansion tube 6 can be reduced. The amount of pressurized air for telescopic movement.

Further, in the first pump, the liquid contact portion 6f of the bottom wall 6c of the bellows 6 is The reinforcement is achieved by actuating the plate 10 as described above, so that the bottom wall 6c of the bellows 6 need not be a thick wall having a strength comparable to the pressure of the pump chamber 7, as long as it has the screw 16 and the mounting plate. 17 is sufficient for the connection to the actuating plate 10 as necessary and sufficient wall thickness. Therefore, similarly to the first pump, the bottom wall 6c of the bellows 6 can be made as thin as possible as compared with the conventional telescopic pump described at the beginning, and the weight of the bellows 6 can be reduced.

Further, in the first and second pumps, the liquid contact portion 6f of the bottom wall 6c of the bellows 6 is in close contact with the opposite end faces 6g, 10c of the actuating plate 10, and an annular sealing member (O-ring) is used. 15 sealing the adhesive portions 6g, 10c, but as shown in FIGS. 6 to 8, a sealed space 22 sealed by the annular sealing member 15 is formed between the opposite end faces 6g, 10c, and will be uncompressed. The fluid 23 is filled in the sealed space 22.

6 is a longitudinal sectional side view showing another modification of the telescopic pump of the present invention, FIG. 7 is an enlarged view of a main portion of FIG. 6, and FIG. 8 is a longitudinal sectional front view taken along line VIII-VIII of FIG. The telescopic pump (hereinafter referred to as "third pump") shown in Fig. 6 is a lateral double-acting type telescopic pump, which has the same configuration as that of the second pump except for the following points. In addition, the same components as those of the second pump are denoted by the same reference numerals as those in FIGS. 3 to 5 in FIGS. 6 to 8 , and detailed description thereof will be omitted.

In the third pump, as shown in FIGS. 6 and 7, a circular recess is formed on the outer surface of the liquid contact portion 6f of the bottom wall 6c of each of the bellows 6, that is, the center of the bottom wall 6c of the bellows 6 is formed. The wall thickness (thickness in the axial direction) of the liquid contact portion 6f is thinner than the wall thickness of the outer peripheral portion 6e, and the circular concave portion is formed between the liquid contact portion 6f and the opposite end faces 6g, 10c of the actuation plate 10. The space 22 formed. Further, the space 22 is a sealed space by the annular seal member 15 disposed between the outer peripheral portion 6e of the bottom wall 6c of the bellows 6 and the actuating plate 10. Again, In the annular seal member 15, an O-ring is used similarly to the second pump, and the O-ring 15 is engaged and held by the O-ring groove 15b formed in the actuation plate 10.

Further, an incompressible fluid (for example, a liquid such as oil) 23 is densely packed in the sealed space 22.

Further, in the third pump, as shown in FIGS. 6 and 7, the actuating shaft 20 is formed separately from the actuating plate 10, and the threaded portion 20a formed at the front end of the actuating shaft 20 is screwed to the female thread formed on the actuating plate 10. The recessed portion 10f is sealed by the O-ring 24, whereby the both 10 and 20 are integrally coupled.

Further, in the third pump, as for the pump chamber in the suction step (for example, the pump chamber on the left side shown in Fig. 6), the pump is operated by the suction step by the stretching operation of the bellows 6 The pressure of the chamber 7 is reduced to become a negative pressure. Therefore, the bottom wall 6c of the bellows 6 in which only the outer peripheral portion 6e is coupled to the actuation plate 10 is provided with a central portion, that is, the liquid contact portion 6f is negatively pressurized by the plurality of screws 16. The pump chamber 7 is pulled and deformed in a concave shape. However, a non-compressible fluid 23 such as oil is densely filled in the sealed space 22 formed between the liquid contact portion 6f of the bottom wall 6c of the bellows 6 and the opposite end faces 6g, 10c of the actuation plate 10, and is filled with the non-filled space. The sealed space 22 of the compressive fluid 23 functions as a rigid body. Therefore, when the pump chamber 7 is under a negative pressure, the liquid receiving portion 6f of the bottom wall 6c of the bellows 6, the sealed space 22 filled with the non-compressible fluid 23 functioning as a rigid body, and the actuating plate 10 are held to each other. In a state in which it is not separably adhered, the liquid-repellent portion 6f is not deformed into a concave shape by being pulled into the inside of the pump chamber 7, and the volume of the pump chamber 7 does not change in the suction step.

Further, in the pump chamber (for example, the pump chamber on the right side shown in FIG. 6) 7 in the discharge step, the pump chamber 7 is caused by the discharge step by the contraction operation of the bellows 6 The pressure rises to become a high pressure. Therefore, only the bottom wall 6c of the bellows 6 to which the outer peripheral portion 6e is coupled to the actuating plate 10 has a central portion, that is, the pressing portion 6f, which is pressed by the pressure of the pump chamber 7, to the sealed space 22 The problem of deformation into a convex shape. However, since the sealed space 22 functions as a rigid body filled with the incompressible fluid 23 as described above, the pressing force acting on the pressure of the pump chamber 7 of the liquid contact portion 6f of the bottom wall 6c of the bellows 6 is formed. The movable plate 10 is received by the metal through the sealed space 22 that functions as a rigid body. Therefore, the liquid contact portion 6f does not have a problem of deformation at the time of the discharge step, and the volume of the pump chamber 7 does not change during the discharge step.

As described above, according to the third pump, similarly to the first and second pumps, the bottom wall 6c of the bellows 6 does not occur due to the pressure fluctuation of the pump chamber 7 in any of the steps of the suction step and the discharge step. In the case of deformation, there is no problem that the volume of the pump chamber is substantially changed, and the amount of liquid to be supplied (the amount of discharged liquid) and the amount of circulating fluid are unstable and deviated, and an appropriate pump function can be exerted.

Further, in the third pump, since the liquid receiving portion 6f of the bottom wall 6c of the bellows 6 is reinforced by the actuating plate 10 via the sealed space 22 as described above, the bottom wall 6c of the bellows 6 can be borrowed as long as it has It is sufficient and sufficient wall thickness to connect the outer peripheral portion 6e to the actuating plate 10 by the screw 16 and the mounting plate 17, and the central portion, that is, the liquid receiving portion 6f, can be larger than the first and second pumps. The thickness is reduced in thickness, so that the telescopic tube 6 can be greatly reduced in weight.

Furthermore, the present invention can be preferably applied to a single-acting type telescopic pump, in addition to a double-acting type telescopic pump such as the first to third pumps.

1‧‧‧ spitting pathway

2‧‧‧Inhalation pathway

3‧‧‧ pump head

4‧‧‧Cylinder shell

4a‧‧‧Exhaust port

4b‧‧‧Air supply space

4c‧‧‧ pressurized air

5‧‧‧ pump casing

6‧‧‧ telescopic tube

6a‧‧‧Walls

6b‧‧‧Open end

6c‧‧‧ bottom wall

6d‧‧‧ End of the valley

6e‧‧‧outer part

6f‧‧‧ wetted parts

6g‧‧‧ opposite end faces

7‧‧‧ pump room

8‧‧‧Spread side check valve

8a‧‧ ‧ spring

8b‧‧‧ valve body

9‧‧‧Inhalation side check valve

9a‧‧ ‧ spring

9b‧‧‧ valve body

10‧‧‧ actuation board

10a‧‧‧ Body Department

10b‧‧‧Linking Department

10c‧‧‧ opposite end faces

10d‧‧‧Circular recess

10e‧‧‧outer part

10f‧‧‧ female thread recess

11‧‧‧Installation board

12‧‧‧ Connecting rod

12a‧‧‧End screws

13‧‧‧O-ring

14‧‧‧ Nut components

15‧‧‧Aperture sealing member (O-ring)

15a‧‧O ring groove

Claims (3)

A telescopic pump is configured such that a plastic bottomed cylindrical telescopic tube having an opening attached to a pump casing is stretched and contracted in an axial direction, thereby alternately performing a pump chamber formed by surrounding the telescopic tube a step of discharging the liquid from the discharge side check valve to the discharge passage and a suction step of supplying the liquid from the suction passage to the pump chamber via the suction side check valve, wherein the metal plate is movable in the axial direction Supporting the pump casing, and connecting the actuating plate and the bottom wall of the telescopic tube to the outer peripheral portion thereof, such that the central portion of the bottom wall of the telescopic tube, that is, the liquid contacting portion of the pump chamber, is opposite to the actuating plate. The end faces are in close contact with each other, and the close-contact portion is sealed with an annular sealing member. A telescopic pump is configured such that a plastic bottomed cylindrical telescopic tube having an opening attached to a pump casing is stretched and contracted in an axial direction, thereby alternately performing a pump chamber formed by surrounding the telescopic tube a step of discharging the liquid from the discharge side check valve to the discharge passage and a suction step of supplying the liquid from the suction passage to the pump chamber via the suction side check valve, wherein the metal plate is movable in the axial direction Supporting the pump casing, and connecting the actuating plate and the bottom wall of the telescopic pipe to the outer peripheral portion thereof, so that the central portion of the bottom wall of the telescopic pipe, that is, the bottom wall portion of the telescopic pipe facing the pump chamber and the opposite side of the actuating plate A sealed space sealed by an annular sealing member is formed between the end faces, and the sealed space is filled with an incompressible fluid. The telescopic pump according to claim 1 or 2, wherein the annular sealing member is an O-ring, and the O-ring is engaged and held in an O-ring groove formed in a bottom wall of the telescopic tube or an actuating plate.