JP3239785U - hand pump - Google Patents

Abstract

A hand pump having a piston part with a piston seal that can be easily replaced, copes with vibration caused by rotation of a hand push handle, and can be used for a long period of time. A hand pump includes a cylindrical cylinder 10 whose lower end is joined to a water pumping pipe 40 leading to a water source, a discharge chamber 01 provided with a discharge port 02 mounted on the upper end of the cylinder 10, and a discharge chamber 01. It comprises a push handle 30 rotatably attached to a support portion 03 provided outside the cylinder 10, and a piston portion 50 that slides up and down in the cylinder 10 via a piston rod 20 connected to the push handle 30. The piston part 50 is composed of a piston seal made of thermoreversible polyurethane covering the piston core part and its upper outer peripheral surface, and the piston seal has an opening with a different cross-sectional circle size on one end face and the other end face. It is a truncated conical tubular body, and has an opening with a large cross-sectional circle, and an inclined surface is formed from the outer peripheral edge to the inner peripheral edge at the edge of the opening. [Selection drawing] Fig. 1

Description

TECHNICAL FIELD The present invention relates to a hand pump installed in a well, water tank, or the like.

BACKGROUND ART Hand pumps are widely used for pumping water from household wells and water tanks in depopulated areas and farmers, and for supplying water and securing drinking water in the event of disasters such as earthquakes.

Most hand pumps are composed of a cylinder and a piston as means for sucking up water. One end of the cylinder is the suction side, and the other end is the discharge side. A structure is used in which a piston is provided and, as means for reciprocating the piston, a link mechanism is assembled to connect a push handle to the piston via a piston rod.

In such a hand pump, it is necessary to seal the inside of the cylinder pipe on the suction side so that there is no gap between the cylinder and the piston in order to suck water.

As this means, the piston is composed of a wooden piston core generally called a wooden ball and a leather belt (hereinafter referred to as a "leather seal") made of leather of animals such as cows and horses on the outer peripheral surface of the upper part of the core. The leather seal is made to absorb water and expand, and is devised to smoothly slide on the wall surface of the cylinder while keeping the suction side of the cylinder in a sealed state.

However, the leather seal wrapped around the upper outer peripheral surface of the core of the piston expands with water and moves up and down in the cylinder in close contact with the inner wall of the cylinder due to the reciprocating motion of the piston. There is a risk that the sliding surface of this leather seal will deteriorate or harden.

In addition, since the hand pump is used in underground water or a reservoir, dust and the like enter this gap, and the reciprocating motion of the piston rod may scratch and damage the sliding surface of the leather seal.

Under such circumstances, the function as a seal cannot be maintained and the ability to suck up groundwater is reduced, so the leather seal must be periodically replaced.

This rewinding involves adjusting the length and winding condition of the leather based on the condition of the wooden core of the piston and the wear condition of the inner wall of the cylinder. was needed.

As a means for solving the problem of such leather seals, techniques for piston seals and O-ring packings using synthetic/natural rubber or other resins for elastic members have been developed.

JP-A-2009-13876 JP 2015-21484 A

Shichinosuke Ito, "Polyurethane Thermoplastic Elastomer", Journal of the Japan Rubber Association, Vol. 57, No. 11 (1984) Yasuhiko Takemura, "Current Status and Future Prospects of Thermoplastic Elastomers", Journal of the Japan Rubber Association, Vol. 83, No. 9 (2010)

Rubber is a type of elastomer, and elastomers are classified into thermoset and thermoplastic elastomers, both of which have elastic characteristics. Rubber belongs to thermosetting elastomers, and thermosetting elastomers have problems in that they have a higher specific gravity than thermoplastic elastomers, are difficult to mold, and are expensive.

Also, in general, there are various types of resins, each with different properties and characteristics such as hardness, abrasion resistance, and bending resistance. However, there was a problem as to whether it could be applied to a piston seal that slides on the inner peripheral wall of the cylinder of a hand pump.

In addition, in general, the hand pump works with the hand push handle serving as the force point, the base shaft to which the hand push handle is rotatably attached to the support provided in the pump main body as the fulcrum, and the connecting portion connecting the hand push handle and the piston rod as the point of action. , When the push handle is turned up and down, the vertical movement of the point of action is slight, but the movement draws a minor arc. As a result, the axial reciprocating motion of the piston rod connected to the push handle is not an exact vertical motion, but rather a vertical motion with slight fluctuation.

For this reason, the portion of the piston fixed to the piston rod that contacts the inner peripheral wall of the cylinder is also biased in the same direction as the deflection, and a pressing load is always applied to a certain portion of the upper outer peripheral surface of the piston. A thin ring-shaped seal like an O-ring packing that is fitted into a recess does not have a structure that absorbs and mitigates the impact caused by the load applied to the above-mentioned fixed uneven location, so it is used in wells and the like. There was a problem with using it with a normal hand pump.

Therefore, the present invention can be easily and easily attached to the core of the piston in place of the leather seal, is inexpensive and lightweight, and can be easily molded, and furthermore, it prevents vibration of the piston that cannot be absorbed by the O-ring packing. It is an object of the present invention to provide a long-life hand pump having a piston portion with corresponding piston seals.

The hand pump according to the invention described in claim 1 comprises a cylindrical cylinder whose lower end is connected to a water pipe leading to a water source, a discharge chamber provided with a discharge port mounted on the upper end of the cylinder, and the A hand pump having a hand push handle rotatably attached to a support provided outside a discharge chamber, and having a piston part that slides up and down in the cylinder via a piston rod connected to the hand push handle,
The piston portion is composed of a piston core portion and a piston seal that covers an upper outer peripheral surface of the piston core portion, and the piston seal is a truncated conical tubular body having openings with different cross-sectional circle sizes on one end face and the other end face. and a slanting surface is formed from the outer peripheral edge toward the inner peripheral edge at the edge of the opening having a large cross-sectional circle.

A hand pump according to the invention recited in claim 2 is characterized in that the piston seal recited in claim 1 is made of thermoreversible polyurethane.

According to the present invention, it is possible to provide a hand pump equipped with a piston seal covering the upper outer peripheral surface of the piston, which can be easily replaced in place of a leather seal, and which is applied to vibration of the hand pump which cannot be dealt with with O-ring packing.

FIG. 1 is a sectional view showing the construction of a hand pump. FIG. 2 is a perspective view showing the configuration of a piston portion used in a hand pump. FIG. 3 is an exploded view showing the configuration of a piston used in a hand pump, where (a) is a piston seal and (b) is a piston core.

A hand pump according to an embodiment of the present invention will be described below with reference to FIGS. 1 to 3. FIG.

As shown in FIG. 1, the hand pump comprises a main body comprising a cylinder 10 and a discharge chamber 01 mounted on the upper end 15 of the cylinder, and a piston 50 reciprocably provided inside the cylinder of the main body. , a link mechanism portion composed of a piston rod 20 connected to a piston portion 50, and a push handle 30 for reciprocating the piston portion 50 via the link mechanism portion. The lower end 16 of the cylinder of the main body is joined to a pumping pipe 40 installed perpendicularly to the water surface of a water source such as a well.

The discharge chamber 01 of the main body is a bowl-shaped member with an open top, and has a discharge port 02 for discharging the sucked groundwater and a support part 03 on which a hand push handle 30 is rotatably mounted on a base shaft 22 .

The cylinder 10 is a cylindrical member formed so that the piston portion 50 can smoothly slide up and down along the inner peripheral wall 17 thereof. is joined to the pumping pipe 40 by a flange, and the first suction hole 14 serving as a water flow path is formed. In addition, a first check valve 13 is provided at the lower end 16 of the cylinder, which is a joint portion with the pumping pipe 40, so as to cover the first suction hole 14 and prevent backflow of water sucked up from the pumping pipe 40. there is

The piston portion 50 is composed of a piston core portion 51 and a tubular piston seal 60 having a truncated cone shape covering an upper outer peripheral surface of the piston core portion 51 to be described later.

A second suction hole 55, which serves as a flow path for water, penetrates through the center of the piston core portion 51, and a second check valve prevents backflow of water by covering the outlet of the second suction hole 55. A valve 56 is provided on the upper surface 57 of the piston core 51 . Further, fixing holes 23 for connecting and fixing the piston rod 20 and the piston portion 50 are formed on both sides of the second suction hole 55 in the piston core portion 51 . Both the first check valve 13 and the second check valve 56 are in a closed state when stationary.

The link mechanism part has a function of transmitting the movement of the push handle 30 to the piston part 50 via the piston rod 20, and the upper end of the piston rod 20 is connected to the push handle 30 by the connecting shaft 21, and is divided into two parts. The lower end portion passes through two fixing holes 23 formed in the piston core portion 51 and is fixed to the lower surface 58 of the piston core portion 51 by a nut to link the hand push handle 30 and the piston portion 50 .

When the push handle 30 is rotated up and down, the grip portion 31 of the push handle 30 is the power point, and the base shaft 22 to which the push handle 30 is rotatably attached to the support portion 03 provided in the discharge chamber 01 of the main body is the fulcrum. A connecting shaft 21 connecting the handle 30 and the piston rod 20 acts as a point of action, and the piston portion 50 in the cylinder 10 moves up and down along the axial direction.

As the push handle 30 is moved downward, the piston portion 50 slides upward within the cylinder 10 and moves to the cylinder upper end 15, whereupon the space between the lower surface 58 of the piston portion 50 and the cylinder lower end 16 is formed. , the volume of the suction side 11 becomes large.

At this time, since the second check valve 56 closes the second suction hole 55 , the pressure on the suction side 11 becomes negative, and the first check valve 13 opens to allow water to flow into the suction side 11 from the pumping pipe 40 . . When the piston portion 50 moves to the cylinder upper end 15, the entire inside of the cylinder 10 becomes the suction side 11 and is filled with water. At this time, the first check valve 13 and the second check valve 56 are both closed.

As the push handle 30 is moved upward, the piston portion 50 slides downward within the cylinder 10 to the lower end 16 of the cylinder. At this time, the first check valve 13 is closed by the water pressure generated by the downward movement of the piston portion 50 . On the other hand, the second check valve 56 is opened by the pressure of water flowing in from below the second suction hole 55 , and the water on the suction side 11 in the cylinder 10 flows between the upper surface 57 of the piston portion 50 and the cylinder upper end 15 . It flows upward to the discharge side 12 which is a space of .

When the lower surface 58 of the piston portion 50 is positioned at the cylinder lower end 16, almost all of the water in the cylinder 10 has moved to the discharge side 12, which is the space between the upper surface 57 of the piston portion 50 and the cylinder upper end 15. Become.

When the push handle 30 is moved downward to move the piston portion 50 upward, the second check valve 56 is closed by the pressure of water on the discharge side 12 of the cylinder 10, and the pressure inside the cylinder 10 is increased. The water is pushed up into the discharge chamber 01 by the piston part 50 and flows out from the discharge port 02 . At the same time, the first check valve 13 opens due to the negative pressure on the suction side 11 , sucking up water from the pumping pipe 40 to the suction side 11 in the cylinder 10 .

By repeating the vertical movement of the push handle 30, the series of operations described above can be continuously performed and groundwater can be pumped up continuously.

Thus, in order for the water to be sucked up by the vertical movement of the piston portion 50 in the cylinder 10, the piston seal 60 of the piston portion 50 must be interposed between the piston core portion 51 and the cylinder 10 to form the cylinder inner peripheral wall 17. The piston part 50 needs to slide smoothly inside the cylinder 10 while maintaining the airtightness of the contact part. Therefore, the piston seal 60 is required to have elasticity, flexibility, wear resistance, etc. to ensure its function.

2 and 3 are a perspective view and an exploded view showing the configuration of the piston portion 50. FIG.
The piston portion 50 is composed of a piston core portion 51 , a piston seal 60 and a second check valve 56 provided on an upper surface 57 of the piston core portion 51 .

The piston core portion 51 shown in FIGS. 2 and 3(b) is made of a cylindrical wooden material and consists of a first core portion 52, a second core portion 53, and a connecting wall 54. The first core portion 52 has a cylindrical shape extending from the lower surface 58 to the connecting wall 54 with the connecting wall 54 serving as the partition wall between the core portion 52 and the second core portion 53 as a boundary. It has a shape in which the diameter is reduced toward 54 and the outer peripheral surface is formed to be gradually smaller. Moreover, the height of the first core portion 52 is set longer than the height of the second core portion 53 .

A second water absorption hole 55 for introducing water is formed in the axial center of the piston core 51 through the piston core 51, and the piston rod 20 and the piston core 51 are formed on both sides of the piston core 51. A fixing hole 23 is formed for connecting the . A second check valve 56 , which is a movable valve for preventing backflow of water, is fixed to the upper surface 57 of the piston core 51 so as to block the second water suction hole 55 .

As shown in FIGS. 2 and 3, the piston portion 50 is configured by fitting a piston seal 60 (described later) to the second core portion 53 of the piston core portion 51 .

As for the material of the piston seal 60 shown in FIGS. 2 and 3(a), the present inventor investigated a material having elasticity similar to that of rubber as a substitute for leather seals and among resins, and found thermoplastic elastomer. (hereinafter referred to as “TPE”).

Regarding the structure and physical properties of TPE, in order to demonstrate its performance, it is necessary to contain both a flexible component (rubber phase or soft segment) and a molecular constraint component (resin phase or hard segment) in the material. Based on the knowledge that basic physical properties such as mechanical properties, heat resistance, and oil resistance of TPE are determined by the type of segment, we developed hard segment styrene (polystyrene), olefin (polypropylene, polyethylene), and vinyl chloride (hard segment). Crystalline polyvinyl chloride), urethane-based (polyurethane), ester-based (aromatic polyester), amide-based (polyamide), and fluorine-based (fluororesin) TPEs were tested. As a result, urethane-based (TPU) TPE, which has relatively high abrasion resistance, bending resistance, and impact resilience, was selected as the material for the piston seal.

A thermoplastic polyurethane elastomer (hereinafter referred to as "TPU") has properties such as excellent elasticity and flexibility, stretchability, resistance to tension, tearing and abrasion, and shock absorption. Moreover, compared with thermosetting elastomers such as rubber, it is lightweight, easy to process, and can be manufactured at a relatively low cost.

For this reason, TPU was selected as the material for the piston seal 60 because it functions as the piston seal 60 of the hand pump and is practical in terms of manufacturing, cost, and workability.

The soft segment of this TPU includes polyester TPU and polyether TPU, but polyester TPU is more preferable because of its superior wear resistance and moldability.

As shown in FIGS. 2 and 3A, the shape of the piston seal 60 is such that the diameter of the first opening 61 at one end is larger than the diameter of the second opening 62 at the other end, and the outer peripheral surface 63 and the inner peripheral surface Surface 64 is a frusto-conical tubular body having a shape that tapers from one end to the other. The piston seal 60 is fitted to the piston core portion 51 with the large-diameter first opening 61 facing upward and the small-diameter second opening 62 facing downward.

The outer diameter of the first opening 61 is adjusted and set to be larger than the inner diameter of the cylinder 10, and is fitted to the second core 53 of the piston core 51 when the piston 50 moves up and down in the cylinder 10. The outer peripheral surface 63 near the first opening 61 of the piston seal 60 is in strong contact with the inner peripheral wall 17 of the cylinder 10, thereby maintaining the airtightness of the intake side 11 of the cylinder 10 and enabling sliding within the cylinder 10. It is the size to

In addition, the inner diameter of the second opening 62 is adjusted to be smaller than the diameter of the connection wall 54 of the second core 53 . By pushing the second opening 62 of the piston seal 60 into the connecting wall 54 of the piston core 51 , the piston seal 60 can be fixed to the piston core 51 .

The thickness of the piston seal 60 can cope with the pressing load generated inside the cylinder 10, prevents it from being turned up, and maintains the airtightness of the intake side 11 of the cylinder 10 to enable sliding inside the cylinder 10. thickness. The width of the connecting wall 54 is adjusted based on the thickness of the piston seal 60 .

The height of the piston seal 60 is set longer than the height of the second core portion 53 of the piston core portion 51 . That is, when the piston seal 60 is fitted to the second core portion 53 and the second opening portion 62 of the piston seal 60 is in contact with the connecting wall 54 , the first opening portion 61 exceeds the upper surface 57 of the piston core portion 51 . It preferably extends to the height of the second check valve 56 provided on the upper surface 57 .

When the piston seal 60 is fitted to the second core portion 53, the piston seal 60 and the piston core portion 51 can be separated without creating a gap between the inner peripheral surface 64 of the piston seal 60 and the outer peripheral surface of the second core portion 53. can be combined. At this time, since the height of the piston seal 60 is longer than the height of the second core portion 53 , the edge of the first opening portion 61 of the piston seal 60 extends above the upper surface 57 of the piston core portion 51 to form the projecting portion 69 . to form

Due to the characteristics of the TPU that forms the piston seal 60, the projecting portion 69 serves as a buffer area for the pressure load generated when the piston portion 50 comes into contact with the inner peripheral wall 17 of the cylinder due to vibration of the hand pump. , and the intake side 11 of the cylinder 10 can be kept sufficiently airtight.

An inclined surface 65 is formed at the edge of the first opening 61 from the outer peripheral edge 66 toward the inner peripheral edge 67 of the piston seal 60 . By adding the inclined surface 65 between the outer peripheral edge 66 and the inner peripheral edge 67, it is possible to respond more flexibly to the pressing load generated in the cylinder 10, and to make the vertical sliding in the cylinder 10 smoother. can be done.

In addition, a plurality of nail holes 68 may be provided in the outer peripheral surface 63 near the edge of the second opening 62 to allow the piston seal 60 to be tightly fitted to the second core 53 through which nails or screws are passed.

In this nail hole 68, the piston core 51 is made of wood and the second core 53, which is the piston seal cover, is deformed due to deterioration or the like due to long-term use. If there is looseness in the fitting of the piston core portion 51 and the piston seal 60, the piston core portion 51 and the piston seal 60 can be firmly fixed by driving a nail.

By attaching the piston part 50 having the piston seal 60 made of thermoreversible polyurethane to the hand pump in this way, the cylinder pressure generated when the hand push handle 30 is rotated up and down is applied to a certain point on the upper outer peripheral surface of the piston part 50. It is possible to flexibly adapt to the pressing load in contact with the inner peripheral wall 17, avoid wear and damage due to excessive contact with the inner peripheral wall 17 of the cylinder, and perform the pump function. Moreover, this can reduce the maintenance of the piston portion 50 and contribute to the improvement of workability such as replacement of the piston seal 60 .

As described above, according to the hand pump according to the present embodiment, the life of the piston seal 60 of the piston portion 50 is improved, and workability such as attachment and replacement of the piston seal 60 in the piston portion 50 is significantly improved. It becomes possible to

According to the present invention, it is possible to provide a hand pump equipped with a piston seal which can be easily replaced in place of a leather seal and which covers the upper outer peripheral surface of the piston and which is applied to vibration of the hand pump which cannot be dealt with with an O-ring packing.

01 Discharge Chamber 02 Discharge Port 03 Support Part 10 Cylinder 11 Suction Side 12 Discharge Side 13 Movable Valve 1
14 suction hole 1
REFERENCE SIGNS LIST 15 Cylinder upper end 16 Cylinder lower end 17 Cylinder inner peripheral wall 20 Piston rod 21 Connecting shaft 22 Base shaft 23 Fixing hole 1
24 fixing hole 2
30 push handle 31 grip portion 40 pumping pipe 50 piston portion 51 piston core portion 52 first core portion 53 second core portion 54 connecting wall 55 suction hole 2
56 movable valve 2
57 upper surface 58 lower surface 60 piston seal 61 first opening 62 second opening 63 outer peripheral surface 64 inner peripheral surface 65 inclined surface 66 outer peripheral edge 67 inner peripheral edge 68 nail hole 69 protrusion

Claims (2)

A cylindrical cylinder whose lower end is connected to a pumping pipe leading to a water source, a discharge chamber provided with a discharge port mounted on the upper end of the cylinder, and a support portion provided outside the discharge chamber so as to be rotatable. A hand pump having a hand push handle mounted thereon and a piston portion that slides up and down in the cylinder via a piston rod connected to the hand push handle, wherein the piston portion includes a piston core and an upper portion of the core. It is composed of a piston seal that covers the outer peripheral surface, and the piston seal is a truncated cone tubular body having an opening with a different cross-sectional circle size on one end surface and the other end surface. A hand pump, characterized in that an inclined surface is formed from the peripheral edge toward the inner peripheral edge. 2. The hand pump of claim 1, wherein said piston seal is formed of thermoreversible polyurethane.

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