JPH06504828A - Seals for high pressure pumps - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Seals for high pressure pumps (Technical field) The present invention provides high pressure Concerning pumps, the invention particularly relates to reciprocating plunger pumps of this type and Concerning seals such as plunger seals.

, (Background technology) High pressure water pumps are used in many different fields. For example, high pressure Water jets clean various surfaces or cut different materials. Transfer of the present invention A new application of high-pressure water, recently introduced by receiver Toro, is to spray water onto lawns. It's about being mindful. In this application, a high-pressure water sprayer is directed toward the ground and Forms multiple pores in the raw material.

Various pumps are known to supply high pressure water for use in these various applications. ing. One pump has multiple reciprocating pumps, each housed in a separate pump chamber. It has a plunger. Water is directed to each pump chamber through an inlet passage. plastic The engine is connected to a rotating crankshaft. When this crankshaft rotates, each The plungers in turn reciprocate in their pump chambers, causing the water contained therein to Increase the pressure and pump this water out of the outlet passage. U.S. Patent Nos. 4 and 3 No. 52,499 shows a reciprocating plunger pump of this type. There is. Water flows back along the plunger and prevents it from leaking from the high pressure side of the plunger. A seal surrounds this plunger to prevent It consists of a ■-shaped sealing member backed by a backup material made of

This backup member is often made of brass or similar material. however, The inventor believes that this seal has a lifespan that can withstand pressures up to approximately 5,000 psi. I found out that I don't have it.

(Disclosure of invention) Therefore, it is a primary object of the present invention to It has a lifespan and performance that can withstand force, and is suitable for use in reciprocating plunger pumps. The purpose of this invention is to provide a high-pressure seal.

Another object of the invention is to provide means for sealing around the plunger at a height of the plunger. The present invention is to realize a reciprocating plunger type fluid pump provided on the pressure side.

This sealing means is made of a bendable material and has a sealing section having a predetermined cross-sectional structure. Composed of wood. A relatively stiff backup member is used to accommodate the seal member. The inner hole of the sealing member receives the inner hole of the sealing member, and the sealing member acts as a backup member. It is now possible to touch it. This backup member is reinforced with highly reinforced fibers. Made from plastic material.

(Brief explanation of the drawing) Embodiments of the invention will be explained in detail on the basis of the following drawings. In this drawing Identical elements are indicated by the same reference numerals.

FIG. 1 is a sectional view of an improved reciprocating plunger pump according to the present invention; one pump chamber, a pump plunger, and a system around the plunger. The assembly is shown.

FIG. 2 is a cross-sectional view of the improved seal of the present invention.

FIG. 3 is a sectional view of the backup member consisting of the seal portion in FIG. 2. .

(Best mode for carrying out the invention) The present invention relates to a pump designated by reference numeral 2 in FIG. Water is pumped at pressures reaching 5,000 psi. Pump 2 has at least one A pump head 4 having one, preferably one or more pump chambers 6 is provided. on the other hand, One pump chamber 6 is shown in FIG. 1, and pumps of this type usually have at least It is equipped with three pump chambers 6. The reciprocating plungers 8 each have a pump chamber 6 is stored.

The plunger 8 has a working or high pressure end 10 which is housed in the pump chamber 6. Ru. The other end 12 of the plunger 8 extends outwardly from the pump head 4 and is connected to a conventional connection. It is rotatably connected to the rank shaft 14 by a rod (path shown).

When the crankshaft 14 is rotated by a suitable driving source, the plunger 8 is rotated by each pump. It has a working end 10 that reciprocates in the pool chamber 6. Generally, plunger 8 is They circulate out of phase with each other.

The pump head 4 includes an inlet passage 16 that allows water to enter the pump chamber 6 . plunge The pump chamber 8 is pulled out or pulled back in the pump chamber 6 (i.e., as shown in FIG. side), suction is started in the pump chamber 6, and water is drawn from the inlet passage 16 into the pump chamber 6. bring it into. In addition, the pump head 4 also has an outlet through which water is located in the pump chamber 6. A passage 18 is provided. This causes the plunger 8 to move away from the pump chamber 6 towards the closed end. (left side of Figure 1).

This movement of the plunger 8 increases the pressure of the water and pumps the water into the pump chamber 6. Check valves are provided in the inlet and outlet passages to prevent backflow of water. To prevent.

Plunger 8 is a metal cylinder rod with fixed external dimensions. deer However, the plunger 8 may have a shape different from that shown here. plunge The pump 8 is a simple member that reciprocates within the pump chamber 6, and the water introduced into the pump chamber 6 is Pump out and apply pressure. This type of reciprocating plunger is well known. There is.

The present invention provides an improved sealing arrangement around each plunger 8 on the high pressure end 10. It is equipped with assembly 20.

Seal assembly 20 prevents water from leaking along the outer circumference of plunger 8.

The seal assembly 20 is carried in a retaining recess 21 formed in the pump head 4. , and the plunger 8 is concentric when it is inserted into the pump chamber 6 I try to surround myself with The seal assembly 20 has a pump head 4 connected to the pump 2. is held in place in the recess 21 when bolted to the remaining housing portion of the Ru.

The main parts of the seal assembly 20 include a bendable V-shaped seal member and this part. This is a backup member 24 that comes into contact with the material. The seal member 22 is a chevron seal. known as nitrile and made from nitrile impregnated fiber material or other suitable sealing material. It is being

In FIG. 3, the backup member 24 is a relatively stiff annular ring that A square-shaped inner hole 26 is provided on the seal member 22. As shown in Figure 1, the backup The cap member 24 is in direct contact with the seal member 22, and the seal member 22 is in contact with the fitting V. The shape is received within a bore 26 of the shape.

Referring to FIG. 2, the seal assembly 20 also includes a front ring 28, which The ring is attached to the V7 section of the seal member 22 that contacts the front end of the seal receiving recess 21 on the closed side. Accepted within the area. The ring 22 is connected to the seal member 2 with respect to the backup member 24. Hold 2. In addition, the metal seal holding member 30 supports the backup member 24. It is located on the other end side, that is, on the back side. The seal holding member 30 is attached to the pump head 4 When the back-up member 24 and the remaining housing of the pump 2 are bolted together, sandwiched between the parts. The seal retaining member 30 is generally attached to the plunger 8. A U-shaped low-pressure water sealing member 32 is provided for further sealing. .

This low pressure seal member 32 prevents further leakage of water that has flowed beyond the first seal member 22. Prevent this from happening.

In a typical pump 2, the backup member 24 is typically made of a hard metal material, e.g. made of brass. Reach about 5,000 psi with a pump like this Attempts to pump water with pressure are useless with the above seal 20 for various reasons. This was discovered by the present inventor. The brass backup member 24 is a sealing member. 22 and causes damage to the inner diameter of the seal lip, shortening its life.

In addition, the sealing member 22 is pushed out from the brass backup member 24 by the above pressure. The seal effect cannot be achieved.

In order to solve this problem of seal life, the present inventors developed The back cover is made of plastic material selected so that it can be used without tension. I considered making a top member 24. This plastic backup member Under high pressure filling the gap between plunger 8 and the surrounding case wall The sealing member 22 has a certain degree of flexibility or curvature, and has good protrusion of the sealing member 22. It was designed to prevent

However, the inventor also discovered that the force applied by the rotation of the crankshaft It is recognized that the pull-up member 24 is exposed to a considerable load from the side of the plunger 8. I met. In this way, the seal member 22 also functions as a bearing member for the plunger 8. have.

Inventors have tried various materials to design suitable backup members. Na Iron had a tendency to swell in water and was not considered suitable. Ba The backup member 24 may be made of various plastics, such as Teflon or Delrin. It was also reinforced with carbon fiber. However, these materials It was not able to adequately handle the load from both sides, and it was also not strong enough to withstand wear.

Thereafter, the inventor replaced the backup member 24 with plastic reinforced with high-strength fibers. For example, the idea was to manufacture it from an aramid fiber known as Kevlar. . In particular, some backup members 24 are made of acetal polymer plastics, e.g. For example, Kevlar fibers cut to lengths of approximately 378 inches were added to Delrin shaped material. Manufactured by mixing pellets. This Kevlar fiber has a weight ratio of is about 30%. This mixture is then backed up using conventional injection molding methods. It is integrally molded as a pull member 24. Delrin and Kevlar are both from DuPont. It is a registered trademark and a well-known and excellent product.

The backup member 24, which is made of Delrin reinforced with Kevlar fiber, is an excellent backup material. Provides a pull member. This backup member 24 reaches 5,000 psi. Prevents seal ejection due to pressure. In addition, heat is not transmitted to the sealing member 22. So it has excellent friction properties. In addition, reciprocating plunger/crank It can sufficiently handle the lateral loads applied to the shaft structure. Therefore, the point of economic structure is Pump 2 shall pump water at a pressure reaching at least approximately 5,000 psi. Can be done.

When manufacturing the backup member 24, the Kevlar fiber is manufactured by DuPont Delly. However, Celanise also Manufactures a lurin-shaped material, an acetal polymer known as Cercon. Ru. Kevlar fibers mix well with Cercon brand acetal polymer.

In this way, the backup member 24 is made of Kevlar fiber by Celanise Co., Ltd. Mix with acetal polymer manufactured and sold under the trade name "Cercon" Preferably, it is manufactured by.

The present invention can be modified in various ways as will be apparent to those skilled in the art, and the claims of the present invention may be modified. The scope is limited only by the appended claims.

Claims (14)

[Claims] 1. a pump head having at least one pump chamber; inlet means for admitting fluid into said pump chamber; and fluid in said pump chamber. an outlet means for allowing fluid to exit the pump chamber after the pump has been pressurized; The high-pressure end is housed in the pump chamber, and when the high-pressure end moves toward one end of the pump chamber, a plunger that compresses and pressurizes the fluid contained in the pump chamber when the pump is pumped; the front with sufficient force to pressurize the fluid to at least about 5,000 psi. a drive means for reciprocating the plunger within the pump chamber; Located at the high pressure end of the plunger and sealing around the plunger, the pump To prevent the pressurized fluid in the chamber from leaking between the area around the plunger and the pump chamber. For this purpose, a sealing means consisting of a sealing member and a relatively hard back-up member is provided. , The sealing member is made of a bendable material and has a predetermined shape extending between the front and back surfaces. The backup member has a cross-sectional shape that is similar to the cross-sectional shape of the seal member. a receiving inner hole, and the back surface of the sealing member is brought into contact with the inner hole so that the surfaces are brought into contact with each other. the seal member is supported by the inner hole of the backup member, and , the backup member is made of plastic material reinforced with high reinforcement fibers. A reciprocating plunger type fluid pump characterized by: 2. Claim characterized in that the plastic material consists of an acetal polymer. Item 1. Reciprocating plunger type fluid pump. 3. Highly reinforced fibers contain approximately 30% by weight of the backup material. The reciprocating plunger type fluid pump according to claim 2, characterized in that: 4. The reciprocating plunger type fluid pump according to claim 2. 5. Highly reinforced fibers contain approximately 30% by weight of the backup material. The reciprocating plunger type fluid pump according to claim 5. 6. The reciprocating prism according to claim 1, wherein the highly reinforced fiber is an aramid fiber. Langer type fluid pump. 7. The sealing member is a chevron-shaped seal having an approximately V-shaped cross-sectional structure, and The inner bore of the cup-up member is V-shaped to receive the seal member therein. 2. A reciprocating plunger type fluid pump according to claim 1. 8. having at least one pump chamber for allowing fluid to flow into the pump chamber; a pump head comprising an inlet means and an outlet means for said fluid to exit the pump chamber; Do and a first high pressure end contained within the pump chamber and a first end extending outwardly from the pump head; a reciprocating plunger having two ends; during operation of the pump to pressurize fluid contained in the pump chamber through the inlet means; A driving means for continuously reciprocating the plunger within the pump chamber, and a high pressure side plunger. Seals the circumferential surface of the plunger to prevent fluid leakage between the circumferential surface and the pump chamber. , surrounding the plunger concentrically when the plunger is housed in the pump chamber. a seal assembly comprising: A bendable V-shaped seal member and a backup member that abuts this seal member and the backup member is a backup member adjacent to the seal member. Consisting of a relatively rigid annular ring with a V-shaped inner hole in the side wall; The backup member is in direct contact with one side of the seal member to form a V-shape of the seal member. It fits into a shaped inner hole, and the backup member is made of highly reinforced fibers. Comparison, characterized by being made from acetal plastic material A pump that supplies fluid under high pressure. 9. The driving means includes a rotatable crankshaft connected to the second end of the plunger. 9. The pump of claim 8, further comprising: 10. 10. The pump of claim 9, wherein the fibers are aramid fibers. 11. The drive means pressurizes the fluid within the pump chamber to at least about 5,000 psi. 11. The pump of claim 10, wherein the pump is configured to: 12. Aramid fibers account for approximately 30% by weight of the backup material. 11. The pump of claim 10. 13. The drive means pressurizes the fluid within the pump chamber to at least about 5,000 psi. 9. The pump of claim 8, wherein the pump is configured to: 14. 14. The pump of claim 13, wherein the fibers are aramid fibers.