JPH0258582B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a material testing machine, particularly a crosshead lifting unit for a material testing machine used for material testing such as stress corrosion cracking tests, tensile tests, fatigue tests, etc., and a material testing machine having the lifting unit. This invention relates to a crosshead lifting mechanism and a material testing machine.

Material tests such as stress corrosion cracking tests generally involve connecting a fixed crosshead to one end of the test piece and a movable crosshead to the other end, and displacing the movable crosshead upward or downward at a constant speed to apply tensile stress to the test piece. Or compressive stress is applied. FIG. 1 shows a conventional example of an electric material testing machine, and FIG. 2 shows its load application mechanism. In Figure 1, both ends of test piece 1 are chucks 2a and 2b, and pull rod 3.
It is connected to a fixed crosshead 4 and a movable crosshead 5 via a, 3b, etc. Two lead screws 6a and 6b are screwed into the movable crosshead 5, and as the lead screws rotate, the movable crosshead 5 is displaced upward or downward to apply a load to the test piece 1. The load is sensed by a load cell 7 mounted on a fixed crosshead.

In FIG. 2, the rotational driving force from the drive motor 8 is transmitted via a pulley 9, a belt 10, and a pulley 11 to a speed switching reduction mechanism 20 consisting of spur gears 12 to 15, clutches 16 to 18, and a reduction gear 19. In addition, the pulley 21, belt 22, pulley 2
3 and the shaft conversion gear means 24 to the main reduction gearbox 25. The main reduction gearbox includes gear trains 26a-28b, gears 28a, 28
The rotational force b is transmitted to spur gears 31 and 32 fixed to the lead screws 6a and 6b via the final transmission gears 29 and 30, thereby rotating the lead screws.

As mentioned above, in the conventional examples shown in Figs. 1 and 2, the load applying mechanism is simply constructed by a conventional combination of a motor, a pulley, a belt, and a gear, and in particular, it has a driving force transmission section. The crosshead lifting mechanism cannot be separated in practice. Therefore, for example, if you want to change the crosshead lifting speed from ultra-low to ultra-high depending on the test material and test purpose, there is a limit to the speed change range, so you will need to replace the reduction gear.
For the above reasons, it is actually extremely difficult to replace the reduction gear. In addition, since one material testing machine is required for one test piece, low-speed tests (e.g.
0.01 to 0.00001 mm/min) on a large number of test pieces requires a large number of material testing machines or an extremely large number of testing days, which is extremely inconvenient.

FIG. 3 schematically shows a conventional example of a so-called multiple type material testing machine that simultaneously tests materials on a plurality of test pieces, and FIG. 4 shows its load application mechanism.

In FIG. 3, test pieces 41 and 42 are placed in a corrosion tank 4.
One end is connected to fixed crossheads 47a, 47b fixed to the upper frame 46 through pull rods 44a, 44b, and the other end is connected through pull rods 48a, 48b and chucks 49a, 49b. and are connected to a common movable crosshead 50. As will be described later with reference to FIG. 4, in the one shown in FIG. 3, a movable crosshead 50 is fixed to a lead screw 51, and the lead screw itself is vertically displaced to apply the same load to multiple test pieces. load. The upper pedestal 46 is supported on the lower pedestal 53 by support columns 52a and 52b.

In FIG. 4, the rotational driving force from the drive motor 55 is transmitted to a reducer 56, a pulley 57, a belt 58,
Pulley 59, shaft conversion gear means 60 and clutch 6
1 to the main reduction gearbox 62,
Final transmission gear 70 is rotated by spur gears 63-69. The inner peripheral surface of the final transmission gear 70 is screwed into the outer peripheral surface of the lead screw 51, and the lead screw 51 has a keyway 51a formed therein.
Since the key 71 enters the keyway, the rotation of the final transmission gear 70 is converted into linear movement of the lead screw 51.

Similar to the devices shown in FIGS. 1 and 2, the conventional devices shown in FIGS. The driving force transmission section and the crosshead lifting mechanism cannot be separated in practice. Additionally, although multiple test pieces can be attached at the same time, the same load can only be applied to them, making it impossible to perform a wide variety of material tests on multiple test pieces at the same time. It was inconvenient.

Furthermore, the conventional examples shown in FIGS. 1 to 4 all have large-sized load-applying mechanisms, which increases manufacturing costs and also increases the floor area of the testing machine.

Broadly speaking, an object of the present invention is to provide a material testing machine in which a load applying mechanism is a driving force generating part;
It is an object of the present invention to solve all of the above-mentioned problems by making it possible to unitize each of the driving force transmission part and the crosshead lifting mechanism part.

More specifically, the first object of the present invention is to make it possible to unitize the crosshead elevating mechanism, and at the same time to simplify the structure.

The second object is to simultaneously make it possible to unitize the drive generation/transmission part and the crosshead lifting/lowering mechanism part in the load applying mechanism, and to simplify the structure thereof.

The third purpose is to provide a material testing machine that can perform a wide variety of material tests on a large number of test pieces at the same time by realizing an extremely simple and compact crosshead lifting mechanism. be.

Other objects and features of the invention will become apparent to those skilled in the art from the description of this specification and the accompanying drawings.

Some preferred embodiments of the present invention will be exemplarily described below with reference to the drawings.

FIG. 5 is an exploded perspective view of a crosshead elevating mechanism in which each component is integrated into a unit according to the present invention, and FIG. 6 is a sectional view of the assembled unit.

In FIGS. 5 and 6, reference numeral 100 designates a driving force generation and transmission unit comprising a drive motor 101, reduction gearboxes 102, 103, and a main reduction gearbox 104. Reduction gear box 102, 10
3 may have any internal configuration, but it should be noted that the output shaft 101a of the drive motor 101 is screwed into the inner peripheral surface of the first gear 102a of the reduction gear box 102, and The output shaft 102b is the first output shaft of the reduction gearbox 103.
It is adapted to be screwed into the inner peripheral surface of the gear 103a,
It is easy to attach and detach each other. Therefore, the driving force generation and transmission unit can also be understood as a combination of the driving force generation unit (motor 101) and the driving force transmission unit (gearboxes 102, 103, 104).

The drive motor 101 has a desired output speed,
Further, the reduction gearboxes 102 and 103 can be easily replaced with those having a desired reduction ratio.

In the main reduction gearbox 104, the driving force is transmitted to the final transmission gear 113 via a clutch 105 and gears 106-112.

In FIG. 5, reference numeral 114 designates a crosshead lifting unit for raising and lowering a movable crosshead 116 fixed to the lower end of the lead screw 115. The lead screw 115 extends through a substantially cylindrical member 117 having a hexagonal nut-shaped head 117a, and as shown in FIG.
The inner peripheral surfaces of 7a are screwed together.

Final transmission gear 11 of main reduction gearbox 104
A recess 113b having a shape corresponding to the hexagonal nut-shaped head 117a of the crosshead lifting unit is formed in the lower skirt portion 113a of 3, and the hexagonal nut-shaped head 117a is removably fitted into the recess 113b. It is made to be. Therefore, rotation of the final transmission gear 113 causes the substantially cylindrical member 117 to rotate. The substantially cylindrical member 117 is the holding member 11
8,119 for rotation about the lead screw 115. The holding member 119 has a key groove 1 formed in the lead screw 115.
A key 120 cooperating with 15a is fixed and prevents rotation of lead screw 115. Holding member 1
18 is fitted into a socket member 120 fixed to the bottom of the main reduction gear box 104, and a key 121 fixed to the holding member 118 and a key groove 122 formed in the socket member 120 cooperate with each other. , prevents rotation of the holding member 118 and the holding member 119 fixed thereto.

Therefore, the rotational movement of the substantially cylindrical member 117 due to the rotation of the final transmission gear 113 is converted into a linear movement of the lead screw.

Upper skirt portion 113 of final transmission gear 113
A through opening 113d is formed in c to allow the upward movement of the lead screw 115, and the upper limit position of the lead screw is regulated by stopping the motor 101 with a limit switch 123. The handle 124 is used to manually rotate the final transmission gear 113 with the clutch 105 disengaged and manually adjust the position of the lead screw.
Incidentally, reference numeral 140 is a frame for fixing to a material testing machine.

In the illustrated embodiment, the crosshead lifting speed was approximately 0.1 mm/min under the following conditions.

Motor rotation speed: 1500 rpm Reduction gear box 102:: 1/10 Reduction gear box 103: 1/75 Main reduction gear box 104: 1/60 (1/2 x 1/2.5 x 1/4 x 1/3) Lead screw screw pitch : 3mm Therefore, the lifting speed V is: V = 1500 x 1/110 x 1/75 x 1/60 x 33 = 0.1 mm/min If a servo motor or pulse motor is used as the drive motor 101, the rotation speed Alternatively, the crosshead lifting speed can be detected and fed back to the motor. Furthermore, if a constant speed is desired, a synchronous rotary motor may be used.

As is clear from the above, according to the present invention, firstly, the crosshead lifting mechanism itself can be made into a compact unit, which makes it easier to adjust and lower the lifting unit.
Replacement becomes extremely easy.

Furthermore, since the entire crosshead elevating mechanism can be completely integrated into a unit consisting of a driving force generating unit, a driving force transmitting unit, and a crosshead elevating unit, it is possible to easily respond to requests for changing the elevating speed. Furthermore, since the entire lifting mechanism is compact, it can be incorporated into a material testing machine.
The entire material testing machine can be configured compactly.

FIG. 7 shows an example of a material testing machine for constant strain rate testing according to the present invention, which is equipped with the crosshead lifting mechanism shown in FIGS.

The tester main body 150 includes a lower pedestal 151, two columns 152a and 152b, and an upper pedestal 153, and a crosshead lifting mechanism similar to that shown in FIGS. 5 and 6 is installed at the center of the upper pedestal 153.

The test piece 154 is immersed in a corrosion tank 155, and its upper end extends outside the tank through a seal portion 156, and is connected to a load detection load cell 158 by an upper chuck 157. The load cell 158
The movable crosshead 160 is connected by the connecting pin 159.
connected to. The lower end of the test piece extends outside the tank through the seal 161 and is connected to a fixed crosshead 164 by a lower chuck 162 and a connecting pin 163.

The structure and operation of the crosshead lifting mechanism are explained in the fifth section.
Since it is the same as that shown in FIG. 6, the explanation will be omitted.
Incidentally, the load cell 158 may be arranged inside a support tube provided between the upper frame 153 and the lifting mechanism, as in the embodiment shown in FIG. 8 which will be described later.

In addition to the effects of the lifting mechanism shown in Figures 5 and 6,
According to the present invention, the material testing machine becomes very compact, and the installation area is significantly reduced compared to conventional ones. Therefore, a table-top testing machine that is inexpensive and easy to move and transport is realized.

Next, FIG. 8 shows a constant strain rate system according to the present invention, which is equipped with a plurality of crosshead lifting mechanisms shown in FIGS. An example of a material testing machine for testing is shown.

In the illustrated embodiment, material tests are carried out independently of each other on four test pieces (only two are shown) under particularly high temperature and high pressure. The pressure vessel 180 is placed in a common pressure vessel 180 including a lid plate 180b that is hermetically fixed to the pressure vessel 180. The pressure vessel 180 has a lid plate 1
The flange portion 180c of the 80b is fixed to the frame 181 to be supported. A heating furnace 182 surrounding a cup-shaped portion 180a of the pressure vessel 180 is supported by a lifting platform 183 and a column 184 for raising and lowering the cup-shaped portion 180a. When attaching and detaching the test piece, the bolt 185 is loosened, and the motor 186 rotates the column 184 to detach the heating furnace 182 and the cup-shaped portion 180a from the cover plate 180b.

As can be seen from the plan view of FIG. 9, four crosshead lifting mechanisms (A to D) are arranged concentrically on the cover plate 180b. To simplify the explanation, the crosshead lifting mechanism (A) on the right side in FIG. 8 and its related configuration will be described.

The crosshead lifting mechanism includes a driving force generating unit 190, driving force transmitting units 191, 192, 193, and a crosshead lifting unit 194 similar to those shown in FIGS. The crosshead lifting unit is fixed on a mounting base 195, and the mounting base 195 is supported by a support cylinder 196 that is hermetically fixed on the cover plate 180b.

The lower end of the test piece 198 inside the pressure vessel 180 is attached to a chuck 201 on a fixed crosshead 200 fixed to the lid plate 180b by an internal load carrying member 199.
connected via. The upper end of the test piece 198 has a chuck 202, and a pull rod 2 that extends through the through opening 203 formed in the cover plate 180b in an airtight manner.
04 and the like, and is further connected to a movable crosshead 208 at the lower end of the lead screw 207 via a pin 206. Therefore, when the lead screw 207 and the movable crosshead 208 are displaced upward, the test piece 1
Tensile stress is applied to 98, and compressive stress is applied when it is displaced downward, and if this is repeated,
Can perform repeated tension and compression tests.

Next, in relation to the lifting unit (C) on the left in FIG. To detect the elongation of the test piece, a detection arm 211 with one end fixed to a pull rod is attached to a support cylinder 212.
The stress-strain curve of the test piece can be determined by a recorder 215 using a differential transformer 213 fixed to the support cylinder and an elongation amplifier 214 connected thereto. By detecting the load and elongation for each of the plurality of test pieces, the stress-strain curve of each test piece can be recorded on the recorder 215.

As described above, according to the present invention shown in FIG. 8, it is possible to simultaneously perform independent material tests on multiple test pieces under different load conditions, which significantly reduces the cost and time required for testing. To,
It can be reduced and shortened. Furthermore, in addition to unitizing the driving force generation unit, driving force transmission unit, and load cell lifting/lowering unit, the measuring equipment is also unitized using the support tube 196, making adjustment of the testing machine even easier.

[Brief explanation of drawings]

Fig. 1 is a front view showing an example of a conventional material testing machine, Fig. 2 is a sectional view showing the load loading mechanism of the device shown in Fig. 1, and Fig. 3 is a front view showing another example of a conventional material testing machine. , FIG. 4 is a sectional view showing the load applying mechanism of the device shown in FIG. 3, FIG. 5 is an exploded perspective view showing the crosshead lifting unit and crosshead lifting mechanism of the present invention, and FIG. 6 is an internal configuration of the lifting mechanism shown in FIG. 5. 7 and 8 are respectively partially sectional front views showing a material testing machine according to the present invention, and FIG.
FIG. 2 is a partial plan view of the drawing device. [Description of symbols of main parts], 100...Driving force generation and transmission unit, 101...Driving force generation unit, 102, 103, 104...Driving force transmission unit, 113b...Fitting part of driving force transmission unit, 114...Crosshead lifting unit, 11
7... Driving force receiving part, 117a... Fitting part of the driving force receiving part, 115, 207... Lead screw, 116, 160, 208... Movable cross head, 164, 200... Fixed cross head.

Claims (1)

[Scope of Claims] 1. A material testing machine having a fixed crosshead and a movable crosshead connected to both ends of a test piece, respectively, and a driving force generation and transmission device that generates and transmits a rotational driving force to apply stress to the test piece. A crosshead lifting/lowering unit for use in the present invention, which includes a lead screw having one end to be connected to the movable crosshead, and a drive force receiver configured to be rotatable in response to rotational drive force from the drive force generation/transmission device. a driving force converting means provided between the driving force receiving part and the lead screw and converting rotation of the driving force receiving part into linear motion of the lead screw in order to apply stress to the test piece; A fitting portion to be engaged with the driving force generation/transmission device is formed at one end of the driving force receiving portion, and the fitting portion of the driving force receiving portion engages with a corresponding fitting of the driving force generation/transmission device. 1. A crosshead elevating unit for a material testing machine, characterized in that it receives rotational driving force from the driving force generation/transmission device by removably fitting into a mating portion. 2. In Claim 1, the fitting portion of the driving force receiving portion has a polygonal nut shape, and the polygonal nut-shaped fitting portion has a corresponding polygonal shape of the driving force generation and transmission device. 1. A crosshead elevating unit for a material testing machine, characterized in that the crosshead lifting unit for a material testing machine is configured to receive rotational driving force from the driving force generation and transmission device by removably fitting into a fitting part formed of a shaped recess. 3 A crosshead lifting and lowering mechanism for use with a material testing machine having a fixed crosshead and a movable crosshead connected to both ends of a test piece, respectively, which generates and transmits a driving force for generating and transmitting rotational driving force to apply stress to the test piece. and a crosshead elevating unit for elevating the movable crosshead, the crosshead elevating unit comprising a lead screw having one end to be connected to the movable crosshead, and a rotational force generated from the driving force generation and transmission unit. a driving force receiving part configured to be able to rotate in response to a driving force; and a driving force receiving part provided between the driving force receiving part and the lead screw to prevent rotation of the driving force receiving part in order to apply stress to the test piece. a driving force converting means for converting linear motion of the lead screw; a fitting part to be engaged with the driving force generation and transmission unit is formed at one end of the driving force receiving part, and the driving force receiving part The fitting portion is configured to receive rotational driving force from the driving force generation and transmission unit by removably fitting with a corresponding fitting portion formed on the driving force generation and transmission unit. Crosshead lifting mechanism for material testing machines. 4. In Claim 3, the fitting portion of the driving force receiving portion has a polygonal nut shape, and the polygonal nut-shaped fitting portion is formed on the driving force generation and transmission unit. A crosshead elevating mechanism for a material testing machine, characterized in that the crosshead lifting mechanism for a material testing machine is configured to receive rotational driving force from the driving force generation and transmission unit by removably fitting into a fitting part consisting of a polygonal recess. . 5. In claim 3 or 4, the driving force generation and transmission unit includes a driving force generation unit that generates rotational driving force, and a driving force transmission unit that is detachably connected to the driving force generation unit. 1. A crosshead lifting mechanism for a material testing machine, characterized in that the driving force transmitting unit is formed with the fitting part that removably fits into the fitting part of the driving force receiving part. 6. A fixed crosshead and a movable crosshead connected to both ends of the test piece, a driving force generation and transmission unit that generates and transmits rotational driving force to apply stress to the test piece, and a crosshead lifting and lowering unit that raises and lowers the movable crosshead. The crosshead lifting unit has a lead screw having one end to be connected to the movable crosshead, and a driving force configured to be able to rotate in response to rotational driving force from the driving force generation and transmission unit. a receiving portion; and a driving force conversion means provided between the driving force receiving portion and the lead screw and converting rotation of the driving force receiving portion into linear motion of the lead screw in order to apply stress to the test piece. a fitting portion to be engaged with the driving force generation and transmission unit is formed at one end of the driving force receiving portion, and a fitting portion of the driving force receiving portion is formed on the driving force generation and transmission unit. 1. A material testing machine, wherein the rotational driving force is received from the driving force generation/transmission unit by removably fitting into a corresponding fitting part. 7. In claim 6, the fitting portion of the driving force receiving portion has a polygonal nut shape, and the polygonal nut-shaped fitting portion is formed on the driving force generation and transmission unit. 1. A material testing machine characterized by being configured to receive rotational driving force from the driving force generation and transmission unit by removably fitting into a fitting part formed of a polygonal recess. 8. In claim 6 or 7, the driving force generation and transmission unit includes a driving force generation unit that generates rotational driving force, and a driving force transmission unit that is detachably connected to the driving force generation unit. 1. A material testing machine comprising: a driving force transmitting unit, the fitting portion being removably fitted to the fitting portion of the driving force receiving portion; 9 A material testing machine for carrying out material tests on a plurality of test pieces, including a plurality of stress-loading devices for carrying out mutually independent material tests, and each of the plurality of stress-loading devices The test piece consists of a fixed crosshead and a movable crosshead connected to both ends of the test piece, a driving force generation and transmission unit that generates and transmits rotational driving force to apply stress to the test piece, and a crosshead lifter for raising and lowering the movable crosshead. The crosshead lifting unit has a lead screw having one end to be connected to the movable crosshead, and a drive configured to be able to rotate in response to the rotational driving force from the driving force generation and transmission unit. a force receptor;
A driving force converting means converts rotation of the driving force receiving part into linear motion of the lead screw in order to apply stress to a test piece provided between the driving force receiving part and the lead screw. A fitting part to be engaged with the driving force generation and transmission unit is formed at one end of the driving force receiving part, and a fitting part of the driving force receiving part is formed in a corresponding one of the driving force generation and transmission unit. 1. A material testing machine characterized in that the rotational driving force is received from the driving force generation/transmission unit by removably fitting into the fitting part. 10 In claim 9, the fitting portion of the driving force receiving portion has a polygonal nut shape, and the polygonal nut-shaped fitting portion is formed on the driving force generation and transmission unit. A material tester is configured to receive rotational driving force from the driving force generation/transmission unit by removably fitting into a fitting part formed of a polygonal recess. 11. In claim 9 or 10, the driving force generation and transmission unit includes a driving force generation unit that generates rotational driving force, and a driving force transmission unit that is detachably connected to the driving force generation unit. 1. A material testing machine comprising: a driving force transmitting unit, the fitting portion being removably fitted to the fitting portion of the driving force receiving portion;