JP2006226455A - Scraper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sufficient durable scraper capable of solving the wear and damage due to the lack of a lubricant and the mixing of dust while it has the sufficient pressure tightness. <P>SOLUTION: It is the scraper 15 to perform the wipering of the dust mixing pressurized fluid on a sliding face of the cylinder 2a or the rod 2b that constitutes a fluid pressure actuator 2. It is the scraper 15 to have the first annular scraper 13 consisting of the elastic material with a lip part 13b while executing the vulcanizing adhesion of a metal ring 13a inside, the second annular scraper 14 consisting of the resin material with a lip part 14a in close to the first scraper 13 that contacts to the sliding face, an annular packing 8 with an edge part 8a arranged by spacing from the first scraper 13 and the second scraper 14 to seal the fluid pressure and a sliding face liquid membrane by contacting the sliding face and an annular back-up ring 9 consisting of the resin material to pressure resist and support the packing 8. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a scraper. Specifically, the first relative movement member and the first relative movement member are relatively inserted into the first relative movement member while sliding. The present invention relates to a scraper that can perform wipering of a dust mixed pressurized fluid existing on a sliding surface with a second relative moving member that moves in an axial direction with sufficient durability. The present invention relates to a pressure-resistant and high-function type scraper suitable for, for example, wiping dusty pressurized fluid existing on a sliding surface of a cylinder or rod constituting a fluid pressure actuator.

  Sliding between the first relative movement member and the second relative movement member that is inserted and slides inside the first relative movement member and relatively moves in the axial direction of the first relative movement member. A scraper made of an elastic material such as synthetic rubber is widely used for wiping of a dust mixed pressurized fluid existing on a moving surface, for example, a wiper of a fluid pressure actuator such as a general hydraulic cylinder or a pneumatic cylinder. The scraper made of an elastic material exhibits a sealing function and a drip-proof function for dust and the outside air in the atmosphere under the condition that a lubricating liquid film exists on the sliding surface of the cylinder or rod of the fluid pressure actuator. This scraper made of an elastic material is also applied to dust wiping with respect to a dust mixed pressurized fluid such as coolant liquid such as water or cutting fluid having poor lubricity.

  However, for example, a scraper made of an elastic material for an oil / pneumatic cylinder is originally used under atmospheric pressure conditions, and is not expected to be used under conditions directly affected by the pressure of a pressurized fluid. However, there are problems in terms of durability (life) and sliding characteristics.

  FIG. 11 is a view of the use situation of a scraper 1 made of an annular and elastic material of low to medium pressure (3.5 MPa or less) type for water / cutting fluid used for a fluid pressure actuator 2 comprising a cylinder 2a and a rod 2b. It is a longitudinal cross-sectional view which shows an example partially. In the example shown in FIG. 11, as the scraper 1, a general annular and elastic material hydraulic / pneumatic cylinder dust seal 3 and a general annular and elastic material hydraulic / pneumatic cylinder packing 4 are used. Reference numeral 5 denotes a bearing.

  On the other hand, FIG. 12 is a longitudinal cross-sectional view partially showing an example of a usage state of a high-pressure (7 to 10 MPa or less) type annular and elastic material scraper 6 for water / cutting fluid used in the fluid pressure actuator 2. FIG. In the example shown in FIG. 12, as the scraper 6, an annular and elastic material dust seal 7 made of vulcanized and bonded metal ring 7a, a highly sealed annular seal 8 and a seal 8 are supported. An annular and resin backup ring 9 is used. Reference numeral 10 denotes a metal spacer for supporting the dust-mixed fluid seal 7, and reference numeral 11 denotes a retaining ring for fixing the dust-mixed fluid seal 7.

  However, if the dust wiper ring with respect to the dust mixed pressurized fluid described above is performed using the scraper 1 shown in FIG. 11 or the scraper 6 shown in FIG. 12, the pressure resistance resulting from the fact that the seals 3 and 7 are made of an elastic material. The scrapers 1 and 6 are used early after the start of use due to various factors such as lack of lubrication, lack of lubricity of the pressurized fluid itself containing dust, and wear and breakage of the seals 3 and 7 made of elastic material due to the mixed dust. The problem of lack of durability that breaks occurs.

  For example, when the operation durability test is performed on the scraper 6 shown in FIG. 12, the required life (100 to 1.5 million repeated operations under a pressure of 7 to 14 MPa) is increased from 500,000 times (pressure: 10 MPa) to 70. The number of repetitions of about 10,000 times (pressure: 7 MPa) causes leakage due to damage and wear due to poor lubrication, making it unusable.

  For the purpose of improving the durability of the dust-mixed fluid seal 7 under the pressurized condition in response to the result of the above operation durability test, the inventors first put an elastic material on the scraper 6 shown in FIG. It was considered to add a resin backup ring for supporting the dust-mixed fluid seal 7 and improving its pressure resistance.

FIG. 13 is a longitudinal cross-sectional view partially showing an example of a usage state of the annular scraper 12 in which an annular and resin backup ring 11 is added to the scraper 6 shown in FIG.
When the scraper 12 was similarly subjected to an operation durability test, the dust-encapsulated fluid seal 7 was supported by the added backup ring 11 so that the dust-encapsulated fluid seal 7 was not damaged. The lip 7b of the dust-mixed fluid seal 7 is worn early due to insufficient lubrication of the moving surface and dust mixing, and the swollen portion is damaged, and the number of repeated operations is approximately the same as the scraper 6 shown in FIG. Caused a leak.

  Thus, in order to provide a scraper having sufficient durability even when applied to dust wiper ring for dust mixed pressurized fluid, it is not enough to improve its pressure resistance, and lack of lubrication. It is also required to solve the early wear and breakage of the lip portion of the dust mixed fluid seal caused by the dust contamination.

  In order to improve both the pressure resistance and durability of the scraper that wipes the dust mixed pressurized fluid existing on the sliding surface of the cylinder or rod constituting the fluid pressure actuator, the material of the dust mixed fluid seal is made elastic. At first glance, it is effective to replace the material with a resin material such as PA, POM, PTFE, or UHMWPE, which excels in sliding characteristics in a pressurized fluid with poor lubricity and scraping performance of mixed dust. Conceivable. However, since the resin material is inferior in flexibility and elasticity compared to an elastic material such as a synthetic rubber and has poor adhesion and followability to the sliding surface of the rod, even if the durability could be improved, It is inevitable that the sealing performance with respect to the dust mixed pressurized fluid, which is the basic performance of the seal, is deteriorated.

  Therefore, as a result of further studies, the present inventor not only supports the inside of the cylinder of the scraper (first scraper) made of an elastic material such as synthetic rubber in the axial direction of the cylinder, but also the lip portion of the scraper. Adds a second scraper made of resin, such as PTFE, that has a lip that makes surface contact with the sliding surface so that it can withstand repeated loads such as pressure deformation and sliding stress between the rod However, if the wiper of the dust mixed pressurized fluid is performed through the second scraper, sufficient elasticity and good adhesion followability with respect to the movement of the rod can be maintained even under a condition where a high pressure is applied. The desired pressure resistance and contamination dust removal function (sealing function) can be achieved. This eliminates early wear and breakage of the lip due to insufficient lubrication and dust contamination. Can, and found that can provide a scraper having a sufficient durability, and completed the present invention.

  As illustrated in FIG. 1, the present invention includes a first relative movement member 2 a (the illustrated example is a cylinder constituting the fluid pressure actuator 2), and a slide inserted into the first relative movement member 2 a. Sliding with a second relative movement member 2b (in the illustrated example, a rod constituting the fluid pressure actuator 2) that moves relatively in the axial direction (vertical direction in FIG. 1) of the first relative movement member 2a while moving. A scraper 15 for wiping dust-injected pressurized fluid existing on the surface, the first scraper 13 being made of an elastic material having a lip portion 13b, and the axial direction of the first relative movement member 2a. An annular ring made of a resin material that is mounted on the inner side of the first relative movement member 2a than the first scraper 13 and has a lip portion 14a that supports the first scraper 13 and that is in surface contact with the sliding surface. A scraper 15, characterized in that it comprises a second scraper 14.

  The scraper 15 according to the present invention is arranged at a position closer to the inner side of the first relative motion member 2a than the second scraper 14 with respect to the axial direction of the first relative motion member 2a, and contacts the sliding surface. Thus, an annular packing 8 having an edge portion 8a for sealing the liquid film of the pressurized fluid that has passed through the second scraper 14 and an annular packing made of a resin material that supports the packing 8 and improves the pressure resistance of the packing 8 It is desirable to provide a backup ring 9.

  These scrapers 15 according to the present invention are in surface contact with the sliding surface by the lip portion 14a of the second scraper 14 being urged toward the sliding surface by the lip portion 13b of the first scraper 13. To do.

  In these scrapers 15 according to the present invention, the lip portion 13b of the first scraper 13 contacts the sliding surface as shown in the first or third embodiment described later with reference to FIG. 1 to FIG. 4 or FIG. Alternatively, as shown by the second or third embodiment described later with reference to FIG. 5 to FIG. 7 or FIG. 8, the lip portion 13-1b of the first scraper 13-1 May be configured not to contact the sliding surface.

  According to the present invention, a first relative movement member and a second relative movement that is inserted and slides inside the first relative movement member and relatively moves in the axial direction of the first relative movement member. Pressurization with dust such as coolant liquid such as water or cutting fluid with poor lubricity existing on the sliding surface with the member, for example, the sliding surface of the cylinder or rod constituting the fluid pressure actuator shown in FIG. When wiping a fluid, it is possible to provide a scraper having sufficient pressure resistance and also capable of solving wear and breakage due to insufficient lubrication and dust mixing, thereby providing sufficient durability.

(Embodiment 1)
The best mode for carrying out the scraper according to the present invention will be described below in detail with reference to the accompanying drawings. In the following description of each embodiment, the first relative movement member in the present invention is a cylinder constituting the fluid pressure actuator and the second relative movement member is a rod constituting the fluid pressure actuator. Take as an example.

The first embodiment is an example related to a scraper in which the lubricity of a dust mixed pressurized fluid is relatively good and the sealing performance is regarded as important.
FIG. 1 is a longitudinal sectional view showing the configuration of the scraper 15 of the first embodiment. FIG. 2 is an explanatory view showing the first scraper 13 and the second scraper 14 extracted from FIG. FIG. 3 is an explanatory diagram showing dimensions of each part of the first scraper 13. Further, FIG. 4 is an explanatory diagram showing the dimensions of each part of the second scraper 14.

  As described above with reference to FIG. 1, the scraper 15 according to the first embodiment wipes the sliding surface of the cylinder 2 a or the rod 2 b constituting the fluid pressure actuator 2. The first scraper 13 made of an elastic material having an excellent sealing performance and the second scraper 14 made of a resin material are combined and further provided with a packing 8 and a backup ring 9 as suitable conditions. .

  The second scraper 14 according to the first embodiment exhibits sufficient elasticity even when a high pressure is applied, and good adhesion followability with respect to the movement of the rod 2b to provide a desired pressure resistance and mixed dust removal function ( Because it has a sealing function), it can solve premature wear and breakage due to insufficient lubrication and dust mixing, and has sufficient durability. For this reason, the 1st scraper 13, the 2nd scraper 14, the packing 8, and the backup ring 9 which are the components of the scraper 15 of Embodiment 1 are demonstrated in order.

[First scraper 13 and second scraper 14]
As shown in FIGS. 1 to 3, the first scraper 13 is an annular and elastic seal member that is attached to the inner peripheral surface of the cylinder 2 a of the fluid pressure actuator 2 via a retaining ring 11. And tightly seal the lip portion 14a and the main body portion 14b of the second scraper 14, and by filling the gap with the rod 2b, the deformation due to a change in the applied pressure or sliding friction is suppressed and the pressure resistance is increased. Further, the lip portion 14a is given elasticity and good followability to the movement of the rod 2b, and in this example, a seal of dust mixed pressurized fluid existing between the cylinder 2a and the rod 2b of the fluid pressure actuator 2 is provided. Also do.

  The first scraper 13 is made of an elastic material. Specifically, the first scraper 13 is sealed in close contact with a lip portion 14a and a main body portion 14b of a second scraper 14, which will be described later, and fills the gap with the rod portion 2b. In addition to suppressing the deformation caused by the change in the applied pressure and sliding friction, the pressure resistance is improved, and the lip portion 14a has elasticity capable of imparting elasticity and good followability to the movement of the rod 2b. It is made of an elastic material that is chemically compatible with the dust mixed pressurized fluid. Examples of such elastic materials include various rubber materials such as NBR, FKM, HNBR, and EPDM.

  Inside the first scraper 13, a metal ring 13a having an L-shaped cross section is vulcanized and bonded. Thereby, the rigidity of the 1st scraper 13 main part is maintained. The metal ring 13a may be disposed inside the first scraper 13 by means other than vulcanization adhesion, for example, press-fitting adhesion.

  The first scraper 13 has a lip portion 13b having a sharp edge formed at the tip. The lip portion 13b is tightly sealed to a lip portion 14a and a main body portion 14b of a second scraper 14 to be described later, and fills a gap with the rod 2b, thereby suppressing deformation due to a change in pressure or sliding friction. Thus, the pressure resistance is increased, and the lip portion 14a is given elasticity and good followability to the movement of the rod 2b. In this example, the tightening allowance δ (FIGS. 2, 3) set at the tip of the own lip portion 13b is provided. The sharp edge at the tip is in contact with the outer peripheral surface of the rod 2b.

  Specifically, referring to FIG. 2, the first scraper 13 has a slight allowance δ with respect to the outer peripheral surface of the rod 2b when mounted at a predetermined mounting position of the cylinder 2a. The outer shape of the second scraper 14 can be in close contact with the second scraper 14. As a result, the first scraper 13 has pressure resistance and uses the elastic force obtained by having the tightening allowance δ so that the lip portion 14a of the second scraper 14 is attached to the outer peripheral surface of the rod 2b. Rush. As a result, the sliding characteristics in the dust mixed pressure fluid with poor pressure resistance and lubricity that cannot be obtained by the first scraper 13 made of an elastic material alone, and the scraping performance of dust contained in the dust mixed fluid are obtained. You can get enough.

  In this example, the sharp edge formed at the tip of the lip portion 13b is configured to come into contact with the outer peripheral surface of the rod 2b. As described above, the seal surface 14c of the seal portion 14a is the outer peripheral surface of the rod 2b. In combination with the contact with the cylinder 2a, the dust mixed pressurized fluid existing between the cylinder 2a and the rod 2b is sealed. Thereby, it is possible to obtain a higher sealing effect.

  On the other hand, as shown in FIGS. 1, 2, and 4, the second scraper 14 is mounted on the inner side of the cylinder 2 a than the first scraper 13 in the axial direction of the cylinder 2 a and supports the first scraper 13. A ring scraper made of a resin material having a lip portion 14a in surface contact with the sliding surface.

  Examples of the resin material used for the second scraper 14 include PTFE, PA, POM, and UHMWPE. Examples of the filler when PTFE is used include carbon fiber, glass fiber, and a special heat resistant resin. If PTFE is used, extremely good sliding characteristics can be obtained even with a dust mixed pressurized fluid having poor lubricity.

  As described above, the seal surface 14c provided on the lip portion 14a of the second scraper 14 abuts on the outer peripheral surface of the rod 2b that forms the sliding surface, and the space between the first scraper 13 and the rod 2b. By filling the gap, the pressure resistance and sliding characteristics of the first scraper 13 are improved, and the dust mixed pressurized fluid existing between the cylinder 2a and the rod 2b of the fluid pressure actuator 2 is sealed.

Here, the first scraper 13 and the second scraper 14 will be described in detail with reference to FIGS.
The scraper 15 of the first embodiment shown in FIGS. 1 to 4 is a combination of a first scraper 13 made of an elastic material and a second scraper 14 made of a resin material. The material and shape of each of the first scraper 13 and the second scraper 14 are appropriately set according to the type of pressurized fluid, dust conditions, pressure conditions, operating conditions, and the specification of the set sliding resistance. Thus, the wiperability, sliding characteristics, pressure resistance and durability of the scraper 15 can be freely adjusted.

  3 and 4, in the scraper 15 of the present embodiment, the first scraper 13 and the second scraper 14 are sufficiently adhered to each other, and the shape of the lip portion 14a of the second scraper 14 is Since it is important to set and adjust the tightening allowance δ of the first scraper 13 and the second scraper 14, these points will be described.

  First, in order to sufficiently secure the close contact between the first scraper 13 and the second scraper 14, the close contact portion (length T1, N) of the first scraper 13 with the second scraper 14 shown in FIG. , H2, H3, radii R1, R2) and the shapes of the second scraper 14 shown in FIG. 4 in close contact with the first scraper 13 (distances t1, n, h2, h3, radii r1, r2). It is important to synchronize the dimensions and position, that is, to allow the gap l1 in the product tolerance range in FIG.

  As a result, as shown by a broken line in FIG. 2, it is possible to minimize deformation strain and stress associated with sliding of the first scraper 13 during pressurization, and the durability of the scraper 13 can be remarkably improved. .

  Further, the rod axial direction distance h0 of the main body 14b of the second scraper 14 is set to be about 3 to 5% larger than the rod axial direction distance H1 of the close contact portion of the first scraper 13 with the second scraper 14. Thus, when the main body 14b of the second scraper 14 is press-fitted into the contact portion of the first scraper 13 and attached, the distance X (FIG. 1, FIG. 1) is formed on the seat surface 13c of the first scraper 13. 2), which can absorb the bending when the first scraper 13 is press-fitted to the inner peripheral surface of the cylinder 2a and the product tolerance of each other, and can reduce the pressure load to the second. The first scraper 13 can be supported by the main body 14 b of the scraper 14, the adhesion between the first scraper 13 and the second scraper 14 can be sufficiently maintained, and the first scraper 13 by the second scraper 14. Support functions (pressure resistance of the acquisition) can be made reliable.

  Further, the lip portion 13b of the first scraper 13 is made of an elastic material and has the above-described tightening allowance δ, so that the lip portion 14a of the second scraper 14 is brought into close contact with the outer peripheral surface of the rod 2b. By filling the gap in this portion, it is possible to suppress deformation caused by a change in applied pressure or sliding friction, thereby improving and stabilizing the scraper sealing function of the first scraper 13b. Furthermore, since the second scraper 14 is made of a resin material, for example, a scraping function for adhering foreign matters such as fiber scraps and a sliding characteristic that is hardly affected by the deterioration of the lubrication condition can be obtained.

  Further, by changing the height of the lip portion 13b (the distance H4 in FIGS. 1 and 2) of the first scraper 13 of the first embodiment, the sealing function and the frictional characteristics exhibited by the first scraper 13 can be changed. Can also be changed. Since the first embodiment is an example in which the sealing performance against high-pressure fluid when the lubricity of mixed dust and fluid is relatively good as described above is important, the first scraper 13 is shown in FIG. By setting the height H4 of the lip portion 13b large, the lip portion 13b is brought into direct contact with the outer peripheral surface of the rod 2b to give priority to ensuring the sealing function. As a result, the second scraper 14 made of a resin material can cope with high pressure while maximizing the sliding characteristics of the second scraper 14, and enhances the scraping function against hard dust such as mixed dust, adhesive dust, and metal. be able to.

  For this reason, it is desirable that the height H4 of the lip portion 13b of the first scraper 13 is a height that does not significantly impair the fastening allowance δ of the lip portion 13b. Specifically, the height H4 of the lip portion 13b is set to be not less than (1/2) and not more than (1/1) the height H5 of the lip portion of the known dust mixed pressurized fluid seal shown in FIG. By setting the rounding r3 of the outer peripheral side shape of the tip portion of the lip portion 14a of the second scraper 14 and the tip portion thickness t2 to be thin, a good adhesion state can be obtained. In addition, by appropriately setting these dimensions, the tightness δ of the lip portion 13b of the first scraper 13 can be changed to finely adjust the sealing performance and the frictional resistance to a desired level.

  In the scraper 15 of the first embodiment, as shown in FIG. 4, the shape of the sliding surface side of the main body 14b of the second scraper 14 is a gently tapered surface having an inclination angle θ. Thereby, even if a minute foreign matter enters, deposits and sliding surface oil film (liquid film) can be discharged to the outside by this taper surface using the operation of the rod 2b.

  As described above, since the scraper 15 of the present embodiment includes both the first scraper 13 made of an elastic material and the second scraper 14 made of a resin material, it is possible to suppress deformation when a high pressure is applied and good Maintains excellent sliding characteristics and has sufficient pressure resistance and dust removal function (sealing function), which can solve early wear and breakage caused by insufficient lubrication and dust contamination. Has excellent durability.

[Packing 8]
As described above, the scraper 15 of the first embodiment includes both the first scraper 13 and the second scraper 14 described above, so that the intrusion of dust contained in the dust mixed pressurized fluid into the inside is prolonged. This can be prevented over a period of time, and this alone is required as a scraper for wiping dusty pressurized fluid, such as coolant, present on the sliding surface of the cylinder or rod constituting the fluid pressure actuator. It has sufficient functions.

  When it is desired to prevent the liquid film of the pressurized fluid from which the dust has been removed by the first scraper 13 and the second scraper 14 from entering the inside of the cylinder 2a in the axial direction, the packing described below is used. It is desirable to use 8 and the backup ring 9 together with the first scraper 13 and the second scraper 14.

  A packing 8 in FIG. 1 is an annular seal member mounted on the inner peripheral surface of the cylinder 2a of the fluid pressure actuator 2. The packing 8 is arranged and mounted on the inner peripheral surface of the cylinder 2a so as to be separated from the second scraper 14 in the axial direction (vertical direction in FIG. 1) of the cylinder 2a with respect to the axial direction of the cylinder 2a.

  The edge 8a on the front end side of the packing 8 abuts on the outer peripheral surface of the rod 2b that forms the sliding surface, so that the dust is removed by the second scraper 14 but passes through the second scraper 14 and the cylinder 2a and the rod. The liquid film of the pressurized fluid existing on the sliding surface 2b is sealed.

Further, the edge portion 8a is urged by a Pascal force accompanying a pressure change of 0 to 21 MPa, for example, and bulges and deforms to reliably close the gap between the cylinder 2a and the rod 2b.
[Backup ring 9]
The backup ring 9 in FIG. 1 is an annular member made of a resin material that is attached to the inner peripheral surface of the cylinder 2a. The backup ring 9 supports the packing 8 adjacent to the end face 8 b of the packing 8. When the backup ring 9 comes into contact with the end face 8 b of the packing 8, the pressure resistance of the packing 8 is improved.

Further, the backup ring 9 is in surface contact with the sliding surfaces of the cylinder 2a and the rod 2b.
As described above, according to the scraper 15 of the first embodiment, it is present on the sliding surface of the cylinder 2a or the rod 2b constituting the fluid pressure actuator 2, for example, a coolant such as water having poor lubricity or a cutting fluid. Even with a pressurized fluid containing dust, sufficient pressure resistance is exhibited, and early wear and breakage due to insufficient lubrication and dust contamination can be solved. In this case, the durability sufficiently satisfying the required life (the number of repetitive operations 100 to 1.5 million times under a pressure of 7 to 14 MPa) is ensured.

  Therefore, according to the first embodiment, the cylinder 2a constituting the fluid pressure actuator 2, which is an example of the first relative movement member, and the first relative movement member are inserted into the first relative movement member while sliding. Existing on the sliding surface with the rod 2b constituting the fluid pressure actuator 2 which is an example of the second relative movement member that moves in the axial direction of the first relative movement member, for example, water or cutting with poor lubricity When wiping dusty pressurized fluid such as coolant liquid, it has sufficient pressure resistance and can also solve wear and breakage due to insufficient lubrication and dust contamination. A scraper 15 having excellent durability is provided.

(Embodiment 2)
Next, a second embodiment will be described. In the following description of each embodiment, portions that are different from the above-described first embodiment will be mainly described, and common portions will be denoted by the same reference numerals in the drawings, and redundant description will be omitted.

  FIG. 5 is a longitudinal sectional view showing a part of an example of the configuration of the scraper 15-1 of the second embodiment. FIG. 6 is an explanatory diagram showing the first scraper 13-1 and the second scraper 14-1 extracted from FIG. Furthermore, FIG. 7 is explanatory drawing which shows the dimension of each part of the 2nd scraper 14-1.

As shown in FIGS. 5 to 7, the scraper 15-1 according to the second embodiment is suitable for use when the dust-proof function is given priority because the lubricity of the mixed dust or fluid is poor.
That is, the scraper 15-1 has a higher tip end height of the lip portion 14-1a of the second scraper 14-1 than the scraper 15 shown in FIG. The shape is thick and sturdy. As a result, the lip portion 13-1b of the first scraper 13-1 is in close contact with the lip portion 14-1a of the second scraper 14-1 to seal this portion, and the second scraper 14-1 Although the lip portion 14-1a is brought into contact with the outer peripheral surface of the rod 2b by being urged, the lip portion 13-1b of the first scraper 13-1 is not brought into contact with the outer peripheral surface of the rod 2b. Thereby, priority is given to the scraping property and sliding characteristic of the mixed dust of the second scraper 14-1.

  Although the method for bringing the first scraper 14-1 and the second scraper 14-1 into close contact with each other is the same as that of the first embodiment described above, there is a situation where the lubricity of mixed dust and fluid is poor. However, in order to achieve a sufficient scraper function, as shown in FIG. 6, a slight tightening allowance δ is set in the lip portion 14-1a of the second scraper 14-1, and the height of the lip portion 14-1a. Is set higher than the height of the lip portion 14a of the first embodiment, and the tip (14-1d portion in FIG. 7) of the lip portion 14-1a is sharpened.

  The tightening allowance δ of the second scraper 14-1 in this example is within the processing tolerance range of the product in consideration of the mounting property to the outer peripheral surface of the rod 2b because the second scraper 14-1 is made of a resin material. And a slight setting that does not cause a gap with the rod 2b during mounting. Regarding the close contact and followability to the rod 2b, the elastic force and tightening allowance by the first scraper 13-1 and the Pascal force by the pressurized fluid (the area corresponding to the height of the lip portion 13-1b of the first scraper 13-1). X pressure).

  Since the second scraper 14-1 of the scraper 15-1 of the second embodiment has such a shape, the tip of the lip portion 14-1a mainly contacts the outer peripheral surface of the rod 2b, and the dustproof function is enhanced. It is done. Thereby, the scraping function with respect to a solid substance can be strengthened when the rubber aggression property by the metal powder, solid substance, adhesive dust, adhesive dust, etc. which are contained in mixing dust is high.

  In the second embodiment, similarly to the first embodiment, the shape on the sliding surface side of the main body 14-1b of the second scraper 14-1 is a gently tapered surface having an inclination angle θ. Thereby, even if a minute foreign matter enters, deposits and sliding surface oil film (liquid film) can be discharged to the outside by this taper surface using the operation of the rod 2b.

(Embodiment 3)
In the scrapers 15 and 15-1 of the first and second embodiments described above, the shape of the sliding surface side of the main bodies 14b and 14-1b of the second scrapers 14 and 14-1 is made to have a gentle inclination angle θ. As a tapered surface, the mixed fine foreign matters and the sliding surface oil film (liquid film) are discharged to the outside by the angle difference of the sliding contact surface using the function of the rod 2b.

However, in this example, the shape of the sliding surface of the main body 14-2b of the second scraper 14-2 is not an gently tapered surface having an inclination angle θ but an edge shape directed toward the inner side.
FIG. 8 shows a second scraper having a main body 14-2b in which the shape on the sliding surface side of the main body portion 14b of the second scraper 14 of the scraper 15 of the first embodiment is an edge shape oriented in the inner side direction. It is a longitudinal cross-sectional view which shows partially the scraper 15-2 provided with 14-2.

  FIG. 9 shows a main body 14- in which the shape on the sliding surface side of the main body 14-1b of the second scraper 14-1 of the scraper 15-1 of the second embodiment is an edge shape oriented in the inner side direction. It is a longitudinal cross-sectional view which shows partially the scraper 15-3 provided with the 2nd scraper 14-3 which has 3b.

  Both the second scraper 14-2 shown in FIG. 8 and the second scraper 14-3 shown in FIG. 9 are enhanced in the function of scraping a sliding surface oil film such as a lubricant on the inside thereof. The second scraper 14-2, 14-3 is prevented from scraping the lubricant, grease, or the like filled therein to the outside, and the durability is improved by maintaining the lubrication function over a long period of time. .

(Embodiment 4)
FIG. 10 is an explanatory diagram illustrating a configuration example of the scraper 15-4 according to the fourth embodiment.
This example is a modified example of the scraper 15-3 shown in FIG. 9, and a rubber having a groove 2c formed annularly in the cylinder 2a and vulcanized and bonded to the metal ring 13a with the first scraper 13-2. By covering, a rubber coating layer press-fitting portion 13-2d that fits in the groove 2c is provided.

  The rubber coating layer having the rubber coating layer press-fitting portion 13-2d is bent and elastically deformed by its own elasticity when the first scraper 13-2d is press-fitted and inserted into the cylinder 2a.

  In the present embodiment, the rubber coating layer press-fitting portion 13-2d formed on the first scraper 13-2 is made to be elastically deformed by utilizing the elasticity and the bending deformation of the rubber coating layer of the first scraper 13-2. By fitting into the groove 2c, the first scraper 13-2 is firmly fitted into the cylinder 2a, thereby eliminating the need for the retaining ring 11 for preventing the withdrawal.

  The rubber coating layer press-fitting portion 13-2d formed in the first scraper 13-2 is fitted into the groove 2c formed in the cylinder 2a, thereby providing high sealing performance, that is, prevention of intrusion of dust mixed pressure fluid from the outside. The function and the escape prevention function can be realized with a simple configuration.

  For this reason, the first scraper 13-2 has a sufficient dustproof function and can be mounted without an auxiliary tool such as a retaining ring. That is, by being press-fitted into the mounting portion of the cylinder 2a and being fitted, the second scraper 14-3 and the second scraper 14-3 are securely joined and fixed. An elastic force that urges the lip portion 14-3a toward the outer peripheral surface of the rod 2b can be exhibited.

  Although the first scraper 13-1 made of an elastic material alone has a certain sealing function, sufficient pressure resistance and sliding characteristics are ensured by using it in combination with the second scraper 14-2 made of a resin material. In addition, it can sufficiently satisfy the durability and reliability, specifically the required life (7 to 14 MPa, 100 to 1,500,000 times) even under conditions where a dust mixed pressurized fluid having poor lubricity acts. Durability of 1.5 million times or more was obtained.

(Modification)
In the above description of the first to fourth embodiments, the first relative movement member in the present invention is a cylinder constituting a fluid pressure actuator, and the second relative movement member is a rod constituting the fluid pressure actuator. Take an example. However, the present invention is not limited to this mode, and the first relative movement member and the first relative movement member are relatively inserted while being inserted and slid inside the first relative movement member. Various devices including the second relative movement member that moves in the axial direction can be applied similarly to the case of the fluid pressure actuator.

  Various materials can be used by appropriately changing the materials and shapes of the first scraper and the second scraper shown in the first to fourth embodiments and the installation position in consideration of the performance required of the scraper. It is possible to provide a scraper that can be used in various types of dust-containing pressurized fluid, temperature, pressure, and the like. These forms are also within the scope of the present invention. For example, it is possible to provide a scraper that can be sufficiently used against mixed dust, adhesive dust, and the like by appropriately selecting and recombining the shape and rigidity of the lip portions of the first scraper and the second scraper. it can.

FIG. 3 is a longitudinal sectional view showing a part of an example of the configuration of the scraper according to the first embodiment. It is explanatory drawing which extracts and shows the 1st scraper and 2nd scraper in FIG. It is description which shows the dimension of each part of a 1st scraper. It is explanatory drawing which shows the dimension of each part of a 2nd scraper. FIG. 6 is a longitudinal sectional view showing a part of an example of a configuration of a scraper according to a second embodiment. It is explanatory drawing which extracts and shows the 1st scraper and 2nd scraper in FIG. It is explanatory drawing which shows the dimension of each part of a 2nd scraper. The longitudinal section which shows a scraper provided with the 2nd scraper which has the main part which made the shape of the sliding surface side of the main part of the 2nd scraper of the scraper of Embodiment 1 the edge shape which goes to the inside side direction FIG. The longitudinal section which shows a scraper provided with the 2nd scraper which has the main part which made the shape of the sliding surface side of the main part of the 2nd scraper of the scraper of Embodiment 2 into the shape of an edge which goes to the inside side direction FIG. FIG. 10 is an explanatory diagram illustrating a configuration example of a scraper according to a fourth embodiment. It is a longitudinal cross-sectional view which shows partially an example of the use condition of the scraper made from the low-medium pressure type cyclic | annular and elastic material for water and cutting fluid used for the fluid pressure actuator which consists of a cylinder and a rod. It is a longitudinal cross-sectional view which shows partially an example of the usage condition of the scraper made from the high pressure type cyclic | annular and elastic material for water and cutting fluid used for the fluid pressure actuator. It is a longitudinal cross-sectional view which shows partially an example of the use condition of the cyclic | annular scraper which added the cyclic | annular and resin-made backup ring to the scraper shown in FIG.

Explanation of symbols

2 Fluid pressure actuator 2a Cylinder 2b Rod 7a Metal ring 8 Packing 8a Edge portion 9 Backup ring 13 First scraper 13b Lip portion 14 Second scraper 14a Lip portion 14b Body 15 Scraper

Claims (5)

A first relative movement member and a second relative movement member that is inserted and slides inside the first relative movement member and relatively moves in the axial direction of the first relative movement member. A scraper that wipes dust-injected pressurized fluid existing on the sliding surface,
An annular first scraper made of an elastic material having a lip portion;
It is made of a resin material that is mounted on the inner side of the first relative movement member relative to the first scraper with respect to the axial direction, and has a lip portion that supports the first scraper and is in surface contact with the sliding surface. A scraper comprising an annular second scraper. The liquid of the pressurized fluid that has been disposed away from the second scraper in the axial direction with respect to the inner side of the first relative motion member and has passed through the second scraper by contacting the sliding surface. An annular packing having an edge to seal the membrane;
The scraper according to claim 1, further comprising an annular backup ring made of a resin material that supports the packing and improves the pressure resistance of the packing.   The lip portion of the second scraper is brought into surface contact with the sliding surface by being urged toward the sliding surface by the lip portion of the first scraper. Scraper.   The scraper according to any one of claims 1 to 3, wherein a lip portion of the first scraper is in contact with the sliding surface.   The scraper according to any one of claims 1 to 3, wherein a lip portion of the first scraper does not contact the sliding surface.

Images