JP7333609B2 - Penetration piston, soil tester and method of moving the lower unit of the penetration piston - Google Patents

Description

Application of Patent Law Article 30, Paragraph 2 On November 15, 2019, Kansai Kiki Seisakusho Co., Ltd. announced in a business negotiation with World Test Co., Ltd. and Seiki Tokyu Kogyo Co., Ltd.

The present invention relates to a penetrating piston, a soil testing machine and a method of moving the lower unit of the penetrating piston.

In civil engineering and construction work, various ground tests are performed to check the condition and strength of the ground. Among these ground tests, there is a CBR test as a type of penetration test mainly designed to confirm the bearing capacity of roadbeds and roadbeds.

In the CBR test defined in JIS A 1211 (Non-Patent Document 1), when testing a commonly-conducted specimen of compacted soil, first, a sample is prepared to create a specimen. Specifically, a mold, a collar and a perforated bottom plate are assembled, a spacer disc is placed in the mold, and a filter paper is laid over the spacer disc. The spacer disk is specified in JIS A 1210 (Non-Patent Document 2) as a metal disk with a height of (50±0.2) mm.

One layer of soil is placed in the mold and tamped a predetermined number of times using a rammer. Repeat this for three layers, remove the collar, and scrape off the protruding soil at the top of the mold with a straight knife. The mold is then inverted to remove the perforated bottom plate and remove the filter paper and spacer discs from the mold. At this time, the upper surface of the specimen is positioned 50 mm below the upper end of the mold, which is the height of the spacer disk.

After that, after a water absorption expansion test, a penetration test is performed by using a CBR tester to penetrate a penetration piston into the specimen. At this time, first, after installing the mold containing the specimen in the loading device so that the center line of the penetration piston and the specimen is aligned, a load of 0.05 kN or less is applied to bring the specimen and the penetration piston into close contact. . After that, the loading device is raised to cause the penetration piston to penetrate at a speed of 1 mm/min, and the reading of the load meter at a predetermined penetration amount is recorded. After recording, remove the load and remove the mold from the loading device. (Non-Patent Document 1).

In the CBR test described in Non-Patent Document 1, the penetration piston is fixed, and in the penetration test, the loading device rises to bring the test piece and the penetration piston into close contact, and then the penetration piston to the test piece. Let it penetrate. The loading capacity of the loading device is set to 50 kN or more, which is a very large load, and since it is necessary to penetrate at a constant speed of 1 mm / min, it is easy to control the amount of penetration, but a screw jack or the like that moves slowly is used. Often used to raise and lower. Therefore, there is a problem that the penetration test takes a very long time.

In order to solve this problem, a CBR tester has been developed in which the upper unit to which the penetration piston is attached is movable in the vertical direction, and the upper unit is lowered to bring the test piece and the penetration piston closer. (Non-Patent Document 3).

Japanese Industrial Standards "CBR test method" (JIS A 1211:2009) Japanese Industrial Standards "Soil compaction test method by tamping (JIS A 1210: 2009) Please refer to the product catalog page on the website of Kansai Kiki Seisakusho Co., Ltd. 70, [online], [searched January 20, 2020], Internet, <https://kansaikiki-s.co.jp/wp/wp-content/uploads/2019/11/catalog_soli.pdf>

However, as stipulated in Non-Patent Document 1, the center line of the penetration piston and the specimen must be aligned, and even in the CBR tester described in Non-Patent Document 3, it is visually confirmed. However, since it is necessary to operate the penetrating piston to descend gradually, a worm gear is used in the upper unit to reduce the rotation speed of the motor or the like. Therefore, the penetration piston must be raised by at least 50 mm to remove the mold containing the specimen after the penetration test is completed, but it is difficult to quickly raise the penetration piston in the upper unit. Therefore, even with the CBR tester, it took a long time for the penetration test.

The present invention has been made to solve such problems, and can withstand a large load generated during a penetration test, and can quickly perform work before and after penetration into a test piece. A penetration piston is provided.

In order to solve the above problems, a penetration piston according to an aspect of the present invention includes a cylindrical shaft body, a handle portion protruding from the side surface of the shaft body, and a substantially T shape provided on the upper surface of the shaft body. a lower member having a letter-shaped engaging member, a cylindrical portion having a large-diameter portion on the lower end side and a small-diameter portion above the large-diameter portion, and a flange portion having a substantially circular opening at the upper end portion; an intermediate member disposed above the lower member and having a through hole for allowing the engaging member to slide vertically; a fixed upper member, wherein the lower member supports the lower portion of the engaging member by the inner peripheral surface of the small diameter portion, supports the shaft by the inner peripheral surface of the large diameter portion, and The engaging portion of the engaging member can be sandwiched between the lower surface of the intermediate member and the upper surface of the spring seat by the elastic member arranged in the opening and the spring seat placed on the upper part of the elastic member. and the upper member is provided with an accommodating portion capable of rotatably accommodating an upper portion of the engaging member.

ADVANTAGE OF THE INVENTION According to one aspect of the present invention, the penetration piston can withstand a large load generated during a penetration test, and it is possible to quickly perform operations before and after the penetration piston penetrates into the specimen.

It is the perspective view which looked at the penetration piston which is 1st embodiment of this invention from above. 1 is a perspective view from above of a lower unit of a penetration piston according to a first embodiment of the present invention; FIG. 1 is a top perspective view of a lower member of a penetration piston according to a first embodiment of the present invention; FIG. It is the perspective view which looked at the intermediate member of the penetration piston which is 1st embodiment of this invention from the (a) upper part, and (b) the perspective view which looked from the lower part. FIG. 10 is an exploded perspective view of part of the penetration piston, which is the second embodiment of the present invention, viewed from above; FIG. 4 is a schematic explanatory diagram of a method of upward movement of the lower unit of the penetration piston, which is one embodiment of the present invention; FIG. 4 is a schematic explanatory diagram of a downward movement method of the lower unit of the penetration piston, which is one embodiment of the present invention;

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. Note that the configurations shown in the following examples are examples, and the present invention is not limited to these configurations.

As shown in FIG. 1, a penetration piston 1 according to one embodiment of the present invention comprises a shaft 2, a handle 3, a lower member 5, an intermediate member 6 and an upper member 7. As shown in FIG.

FIG. 2 is a perspective view from above of the lower unit 1a of the penetration piston 1, which is one embodiment of the present invention. As shown in FIG. 2, a handle portion 3 protrudes from the side surface of the cylindrical shaft body 2 . A substantially T-shaped engaging member 4 is provided in the center of the upper surface of the shaft 2 .

The handle portion 3 may have any shape as long as the shaft body 2 can be manually rotated, and examples thereof include a rod-like member. Moreover, the handle portion 3 may be fixed to the shaft body 2 in advance, or may be attached by screws or the like each time. The material of the handle portion 3 is not particularly limited, and examples thereof include metal.

The engaging member 4 has a substantially T-shape and includes an upper portion 4a and a lower portion 4b. Both ends of the upper portion 4a are engaging portions 4c that engage with other members or the like. As a method of attaching the engaging member 4 to the upper surface of the shaft 2, for example, it is possible to attach using an enameled set or the like. As the material of the engaging member 4, it is possible to use the same metal as the shaft body 2 in consideration of the influence on the penetration test.

As shown in FIG. 3, the lower member 5 has a flange portion 51 at its upper end, and the flange portion 51 is provided with a substantially circular opening 52 . The lower member 5 has a tubular portion 55, a large diameter portion 55a is provided on the lower end side of the tubular portion, and a small diameter portion 55b is provided above the large diameter portion 55a. As shown in FIG. 6, the inner peripheral surface of the large diameter portion 55a supports the shaft 2, and the inner peripheral surface of the small diameter portion 55b supports the lower portion 4b of the engaging member 4. As shown in FIG. As shown in FIG. 5, an elastic member 53 and a spring seat 54 placed on the upper portion of the elastic member 53 are arranged in the opening 52 . Examples of the elastic member 53 include a spring and the like. With this configuration, the engaging portion 4 c of the engaging member 4 can be sandwiched between the upper surface of the spring seat 54 and the lower surface of the intermediate member 6 .

As shown in FIG. 1 , the intermediate member 6 is arranged above the lower member 5 . As shown in FIG. 4, the intermediate member 6 has a through hole 61 that allows the engaging member 4 to slide vertically. The through hole 61 is provided according to the shape of the engaging member 4 .

The upper member 7 is arranged above the intermediate member 6 and fixed together with the intermediate member 6 and the lower member 5 by a fixing member 8, as shown in FIG. The fixing member 8 is not particularly limited as long as the penetration piston 1 does not affect the penetration test, and examples thereof include a cap bolt. Further, as shown in FIG. 6 , the upper member 7 moves the upper portion 4 a of the engaging member 4 when the penetration in the penetration test is completed and the engaging member 4 is slid upward in the through hole 61 . It has a housing portion 71 for housing. In this case, by rotating the lower unit 1a using the handle portion 3 and engaging the engaging portion 4c of the engaging member 4 with the upper surface 62 of the intermediate member 6, the engaging member 4 is placed in the housing portion 71. Locked.

Further, as shown in FIG. 5 , a protrusion 64 for locking the engaging member 4 may be provided on the upper surface 62 and/or the lower surface 63 of the intermediate member 6 . After the engaging member 4 slides out of the through-hole 61, the lower unit 1a is rotated by the handle portion 3, whereby the projecting portion 64 is engaged with the engaging portion 4c of the engaging member 4. , the engaging member 4 can be easily locked. For example, the projecting portion 64 may be a cap bolt or the like. Further, the position of the projecting portion 64 is not particularly limited as long as the engagement member 4 is locked.

A mark M may be provided on the shaft 2 as shown in FIG. The mark M may be attached at a position where the shaft body 2 and the lower body 5 overlap each other and where the lower unit 1a is rotated when the lower unit 1a is moved up and down using the handle 3. It is not necessary to attach it to the whole circumference|surroundings of the shaft 2. FIG. Also, grooves may be carved on the side surface of the shaft 2, or marks may be applied with paint or a seal.

By attaching the penetration piston 1 according to one embodiment of the present invention to a conventional soil testing machine, it is possible to quickly perform work before and after the penetration of the penetration piston 1 into the specimen in the penetration test. The soil testing machine includes a CBR testing machine, but it is not limited to the CBR testing machine as long as it can be used for a penetration test in the CBR test.

FIG. 6 is a schematic illustration of a method of upward movement of the lower unit of the penetration piston, which is one embodiment of the present invention. In the conventional example, after the penetration in the penetration test is completed, the penetration piston is raised by the operation of the soil tester, but as shown in FIG. In the method, the handle portion 3 is used to rotate the lower unit 1a to a position where the engaging member 4 can slide in the through hole 31 (FIG. 6A), and then the handle portion 3 is used to rotate the lower unit 1a. , the upper portion 4a of the engaging member 4 is moved to the housing portion 71 of the upper member 7 by sliding the engaging member 4 vertically upward by sliding in the through hole 61 (FIG. 6 (b)), and by further rotating the lower unit 1a using the handle portion 3, the engaging portion 4c and the upper surface 62 of the intermediate member 6 are engaged to lock the engaging member 4 (FIG. 6 ( c)). After this, the mold containing the specimen is removed. Therefore, compared with the case where the penetration piston is raised by a conventional soil tester using a penetration piston that cannot be moved quickly, the work after penetration into the specimen can be performed quickly.

FIG. 7 is a schematic explanatory diagram of a downward movement method of the lower unit of the penetration piston, which is one embodiment of the present invention. When performing a penetration test on a plurality of specimens, the penetration piston was lowered by the operation of the soil tester after replacing the specimens, but as shown in FIG. 7, a penetration piston 1 according to an embodiment of the present invention In the moving method of the lower unit 1a, after rotating the lower unit 1a to a position where the engaging member 4 can slide in the through hole 61 using the handle 3 (FIG. 7(a)), the handle 3 to move the upper portion 4a of the engaging member 4 to the spring seat 54 ( 7(b)), by rotating the lower unit 1a while pushing down the spring seat 54 using the handle portion 3, the engaging portion 4c of the engaging member 4 is engaged with the lower surface 63 of the intermediate member 6, thereby It is sandwiched between the lower surface 63 of the member 6 and the upper surface of the spring seat 54 (FIG. 7(c)). Therefore, compared with the case where the penetration piston is lowered by a conventional soil tester using a penetration piston that cannot be moved quickly, the work before penetration into the specimen can be performed quickly. Also, during the penetration test, the elastic member 53 urges the engaging portion 4c of the engaging member 4 upward through the spring seat 54, so that the engaging portion 4c of the engaging member 4 moves toward the intermediate member 6. Since it is stably held by the lower surface 63 of the spring seat 54 and the upper surface of the spring seat 54, it does not affect the penetration test in which a very large load is generated.

It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the above description, and is intended to include all modifications within the scope and meaning of equivalents of the scope of the claims.

1 Penetration Piston 1a Lower Unit 2 Shaft 3 Handle 4 Engaging Member 4a Upper Part 4b Lower Part 4c Engaging Part 5 Lower Member 6 Intermediate Member 7 Lower Member 51 Flange 52 Opening 53 Elastic Member 54 Spring Seat 55 Cylindrical Part 55a Large Diameter portion 55b Small diameter portion 61 Through hole 62 Upper surface 63 Lower surface 64 Protruding portion 71 Accommodating portion

Claims (6)

a cylindrical shaft;
a handle protruding from the side surface of the shaft;
a substantially T-shaped engaging member provided on the upper surface of the shaft;
a lower member having a tubular portion having a large-diameter portion on the lower end side and a small-diameter portion above the large-diameter portion, and a flange portion having a substantially circular opening at the upper end;
an intermediate member disposed above the lower member and having a through hole for vertically sliding the engaging member;
an upper member disposed above the intermediate member and fixed together with the intermediate member and the lower member by a fixing member;
with
The lower member supports a lower portion of the engaging member by the inner peripheral surface of the small diameter portion, supports the shaft by the inner peripheral surface of the large diameter portion, and includes an elastic member disposed in the opening and the the engaging portion of the engaging member can be sandwiched between the lower surface of the intermediate member and the upper surface of the spring seat by the spring seat placed on the upper portion of the elastic member;
A penetration piston, wherein the upper member is provided with an accommodating portion capable of rotatably accommodating an upper portion of the engaging member. The penetration piston according to claim 1, wherein the upper surface and/or the lower surface of the intermediate member are provided with protrusions for locking the engaging member. The penetration piston according to claim 1 or 2, wherein a mark indicating a position for rotating the lower unit of the penetration piston is provided on the side surface of the shaft. A soil tester using the penetration piston according to any one of claims 1 to 3. A method of moving a lower unit of a penetration piston using the soil tester according to claim 4,
a step of rotating the lower unit to a position where the engaging member can slide in the through hole by using the handle after the penetration is completed;
After rotating the lower unit, using the handle to raise the lower unit to move the upper portion of the engaging member to the receiving portion;
After moving the upper portion of the engaging member to the housing portion, the lower unit is rotated using the handle portion, thereby engaging the engaging portion of the engaging member with the upper surface of the intermediate member. a step;
A method of moving a lower unit of an intrusion piston comprising: A method of moving a lower unit of a penetration piston using the soil tester according to claim 4,
a step of rotating the lower unit to a position where the engaging member can slide in the through-hole by using the handle after replacing the test pieces during the penetration test of a plurality of test pieces;
a step of moving the upper portion of the engaging member to the spring seat by lowering the lower unit using the handle after rotating the lower unit;
After moving the upper portion of the engaging member to the spring seat, the lower unit is rotated while pushing down the spring seat using the handle, thereby moving the engaging portion of the engaging member to the spring seat. a step of engaging with the lower surface of the intermediate member and sandwiching it between the lower surface of the intermediate member and the upper surface of the spring seat;
A method of moving a lower unit of an intrusion piston comprising: