CN219178504U

CN219178504U - Piezoelectric ceramic deformation measuring device

Info

Publication number: CN219178504U
Application number: CN202223377919.1U
Authority: CN
Inventors: 陈缔; 阮兆辉; 蒋大梅; 杨莞榕; 褚祥诚
Original assignee: Foshan Southern China Institute For New Materials
Current assignee: Foshan Southern China Institute For New Materials
Priority date: 2022-12-14
Filing date: 2022-12-14
Publication date: 2023-06-13
Anticipated expiration: 2032-12-14

Abstract

The utility model provides a piezoelectric ceramic deformation measuring device which comprises a mounting frame and also comprises an adjusting seat mounted on the mounting frame, wherein one end of the adjusting seat is provided with a base, the other end of the adjusting seat is provided with a hand wheel, the base is mounted on the mounting frame, the adjusting seat is provided with a screw rod and an adjusting table screwed with the screw rod, the hand wheel is connected with the screw rod, the adjusting table is provided with a shooting mechanism, the adjusting table is used for adjusting the space position of the shooting mechanism, the adjusting seat is used for adjusting the position of the adjusting table, the base is provided with a detection mechanism and an adjusting mechanism, the detection mechanism comprises a container and a displacement sensor, the container is mounted on the base, the displacement sensor is connected with the adjusting mechanism, the adjusting mechanism is mounted on the base, and the visual range of the shooting mechanism covers the container. The utility model can solve the problem that the data source of the sample measurement is single, so that a measurer can compare and verify the measurement data of the displacement sensor with the measurement data of the shooting mechanism.

Description

Piezoelectric ceramic deformation measuring device

Technical Field

The utility model relates to the field of mechanical measurement, in particular to a piezoelectric ceramic deformation measuring device.

Background

In the existing piezoelectric ceramic deformation detection scheme, a patch type strain gauge and an LVDT linear displacement sensor are mature. The patch type strain gauge is a metal foil, can be stuck on the surface of a sample, requires additional surface treatment before testing, and is stuck with the strain gauge, so that the patch type strain gauge is inconvenient to use. The using method of the LVDT linear displacement sensor comprises the following steps: when the piezoelectric ceramic deformation is detected, the extension rod is used for contacting the surface of the sample, and the displacement of the sample drives the displacement of the sensor, so that the strain is calculated by the displacement. The two methods are contact measurement means, and have obvious defects in the aspects of equipment installation space, sample preparation and the like; the laser displacement sensor in the non-contact measuring equipment can achieve the displacement resolution of 10nm if the effect is desired, and the equipment is relatively expensive.

Meanwhile, in the prior art, the non-contact measuring equipment can also be used for shooting and measuring by using a digital camera, but the digital camera is often only installed by using a simple tripod, and the change of the working distance brought by the camera after the camera is matched with a lens is difficult to conveniently adjust; the focusing process of the sample is very complicated and inconvenient, and the placing position of the sample is also inconvenient to adjust; meanwhile, the data sources of the sample measurement in the prior art scheme are single, and no additional verification means is provided.

Disclosure of Invention

Based on the above, in order to solve the problems that the digital camera is inconvenient to move and the focusing process is very complicated and inconvenient when the digital camera is used for shooting and measuring in the prior art, and the data source of the sample measurement is single, the utility model provides a piezoelectric ceramic deformation measuring device, which has the following specific technical scheme:

the piezoelectric ceramic deformation measuring device comprises a mounting frame, and further comprises an adjusting seat mounted on the mounting frame, wherein one end of the adjusting seat is provided with a base, the other end of the adjusting seat is provided with a hand wheel, the base is mounted on the mounting frame, the adjusting seat is provided with a screw and an adjusting table connected with the screw in a threaded manner, the hand wheel is connected with the screw, the adjusting table is provided with a shooting mechanism, the adjusting table is used for adjusting the space position of the shooting mechanism, the adjusting seat is used for adjusting the position of the adjusting table, the base is provided with a detection mechanism and an adjusting mechanism, the detection mechanism comprises a container and a displacement sensor, the container is mounted on the base, the displacement sensor is connected with the adjusting mechanism, the adjusting mechanism is mounted on the base, and the visual range of the shooting mechanism covers the container.

According to the piezoelectric ceramic deformation measuring device, the adjusting seat, the base, the adjusting table and the shooting mechanism are arranged on the adjusting table, so that the position of the adjusting table can be adjusted by rotating the hand wheel, the position of the shooting mechanism can move along with the position movement of the adjusting table, and meanwhile, the adjusting table can finely adjust the space position of the shooting mechanism, so that the shooting mechanism can perform focusing more conveniently; in addition, the position of the displacement sensor can be adjusted through the adjusting mechanism, so that the displacement sensor can better measure the sample in the container; the container is covered by the visual range of the shooting mechanism, so that the shooting mechanism can also carry out a measuring procedure on a sample in the container, and further the problem that the data source for measuring the sample is single is solved, so that a measurer can compare and verify the measuring data of the displacement sensor with the measuring data of the shooting mechanism.

Further, the adjusting seat comprises a sliding block, the sliding block is connected with the screw rod, and the adjusting table is arranged on the sliding block.

Further, the adjusting table comprises a first sliding table, a second sliding table, a third sliding table, a universal inclination table and a rotary sliding table which are sequentially arranged from bottom to top, the first sliding table is arranged on the sliding block, and the shooting mechanism is arranged on the upper surface of the rotary sliding table.

Further, the first slip table includes first flange, first slide, first rotating handle, first linkage piece and first installation piece, and first flange is installed in the slider, and first flange and first slide sliding connection, first linkage piece are connected with first flange, and first installation piece is connected with first slide, and the middle part and the first linkage piece spiro union of first rotating handle, and the one end and the first installation piece of first rotating handle are connected.

Further, the second slip table includes second turning handle, second connecting block, second installation piece and second slide, second slide and first slide sliding connection, and the second connecting block is connected with first slide, and second installation piece is connected with the second slide, and the middle part and the second connecting block spiro union of second turning handle, and the one end and the second installation piece of second turning handle are connected.

Further, the third slip table includes third rotating handle, third mount pad and third lifter plate, and third mount pad is connected with the second slide, and the third mount pad is equipped with recess and through-hole, and the through-hole communicates with the recess, is equipped with L type piece in the recess, and L type piece rotates with the recess inner wall to be connected, and the third rotating handle passes through the through-hole to be connected with L type piece one end, and the L type piece other end is connected with the third lifter plate.

Further, the universal dip angle platform comprises a push rod, a dip angle seat, a connecting plate, a connecting rod and balls, wherein a placement channel is formed in the dip angle seat, one end of the connecting rod is in butt joint with the connecting plate, the other end of the connecting rod is located in the placement channel, the push rod is connected with the connecting rod through the placement channel, the balls are located between the dip angle seat and the connecting plate, the dip angle seat is mounted on the upper surface of the third lifting plate, and the connecting plate is connected with the rotary sliding table.

Further, the base is provided with a chute, and the container is in sliding connection with the chute.

Further, the displacement sensor is provided with an extension rod for connection to the sample surface.

Further, the detection mechanism further comprises a lifting frame, the displacement sensor is arranged on the lifting frame, and meanwhile the lifting frame is connected with the adjusting mechanism.

Drawings

The utility model will be further understood from the following description taken in conjunction with the accompanying drawings. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the embodiments. Like reference numerals designate corresponding parts throughout the different views.

FIG. 1 is a schematic diagram of a piezoelectric ceramic deformation measuring apparatus according to an embodiment of the present utility model;

FIG. 2 is a schematic diagram of a structure of an adjusting table of a piezoelectric ceramic deformation measuring device according to an embodiment of the present utility model;

FIG. 3 is a schematic diagram of a first sliding table of a piezoelectric ceramic deformation measuring device according to an embodiment of the present utility model;

FIG. 4 is a schematic diagram illustrating an internal structure of a third sliding table of the piezoelectric ceramic deformation measuring apparatus according to an embodiment of the present utility model;

FIG. 5 is a schematic L-shaped block structure of a piezoelectric ceramic deformation measuring device according to an embodiment of the present utility model;

FIG. 6 is a schematic view of a structure of a gimbal table of a piezoelectric ceramic deformation measuring apparatus according to an embodiment of the present utility model;

FIG. 7 is a schematic view showing an internal structure of a gimbal table of a piezoelectric ceramic deformation measuring apparatus according to an embodiment of the present utility model;

FIG. 8 is a schematic diagram of a connecting rod of a piezoelectric ceramic deformation measuring device according to an embodiment of the present utility model;

FIG. 9 is a schematic diagram of a rotating sliding table of a piezoelectric ceramic deformation measuring device according to an embodiment of the present utility model;

FIG. 10 is a schematic structural view of an adjusting mechanism of a piezoelectric ceramic deformation measuring device according to an embodiment of the present utility model;

FIG. 11 is a schematic view of an extension rod of a piezoelectric ceramic deformation measuring apparatus according to an embodiment of the present utility model.

Reference numerals illustrate:

1. a mounting frame; 2. a photographing mechanism; 3. an adjustment table; 31. a first sliding table; 311. a first convex plate; 312. a first slide plate; 313. a first swivel handle; 314. a first connection block; 315. a first mounting block; 32. a second sliding table; 321. a second swivel handle; 322. a second connection block; 323. a second mounting block; 324. a second slide plate; 33. a third sliding table; 331. a third rotating handle; 332. a third mount; 333. an L-shaped block; 334. a groove; 335. a through hole; 336. a third lifting plate; 34. a universal dip angle table; 341. a push rod; 342. an inclination angle seat; 3421. placing a channel; 343. a connecting plate; 344. a connecting rod; 345. a ball; 35. rotating the sliding table; 4. an adjusting seat; 41. a hand wheel; 42. a slide block; 5. a screw; 6. a base; 61. a chute; 7. a detection mechanism; 71. a container; 72. a displacement sensor; 721. an extension rod; 73. a lifting frame; 8. an adjusting mechanism; 81. a rotating wheel; 82. a lifting seat; 83. lifting rod.

Detailed Description

The present utility model will be described in further detail with reference to the following examples thereof in order to make the objects, technical solutions and advantages of the present utility model more apparent. It should be understood that the detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the utility model.

It will be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

The terms "first" and "second" in this specification do not denote a particular quantity or order, but rather are used to distinguish one element from another.

As shown in fig. 1, the piezoelectric ceramic deformation measuring device in an embodiment of the utility model comprises a mounting frame 1, and further comprises an adjusting seat 4 mounted on the mounting frame 1, wherein one end of the adjusting seat 4 is provided with a base 6, the other end of the adjusting seat 4 is provided with a hand wheel 41, the base 6 is mounted on the mounting frame 1, the adjusting seat 4 is provided with a screw 5 and an adjusting table 3 screwed with the screw 5, the hand wheel 41 is connected with the screw 5, the adjusting table 3 is provided with a shooting mechanism 2, the adjusting table 3 is used for adjusting the spatial position of the shooting mechanism 2, the adjusting seat 4 is used for adjusting the position of the adjusting table 3, the base 6 is provided with a detecting mechanism 7 and an adjusting mechanism 8, the detecting mechanism 7 comprises a container 71 and a displacement sensor 72, the container 71 is mounted on the base 6, the displacement sensor 72 is connected with the adjusting mechanism 8, the adjusting mechanism 8 is mounted on the base 6, and the visual range of the shooting mechanism 2 covers the container 71.

According to the piezoelectric ceramic deformation measuring device, the adjusting seat 4, the base 6, the adjusting table 3 and the shooting mechanism 2 are arranged on the adjusting table 3, so that the position of the adjusting table 3 can be adjusted by rotating the hand wheel 41, the position of the shooting mechanism 2 can be moved along with the position movement of the adjusting table 3, and meanwhile, the adjusting table 3 can finely adjust the spatial position of the shooting mechanism 2, so that the shooting mechanism 2 can perform a focusing process more conveniently; in addition, the position of the displacement sensor 72 can be adjusted through the adjusting mechanism 8, so that the displacement sensor 72 can better measure the sample in the container 71; the container 71 is covered by the visual range of the photographing mechanism 2, so that the photographing mechanism 2 can also perform a measurement procedure on the sample in the container 71, and further solve the problem that the data source of the sample measurement is single, so that the measurement personnel can verify the measurement data of the displacement sensor 72 and the measurement data of the photographing mechanism 2.

Preferably, the screw 5 is laid in the direction along the X-axis.

As shown in fig. 1, in one embodiment, the adjusting seat 4 includes a slider 42, the slider 42 is connected with the screw 5, and the adjusting table 3 is mounted on the slider 42, so that the adjusting table 3 can be connected with the screw 5 through the slider 42, and further, when a measuring person rotates the hand wheel 41, the hand wheel 41 is connected with the screw 5, so that the screw 5 can rotate, and meanwhile, the screw 5 can drive the slider 42 to move, and the moving direction of the slider 42 is to and fro along the laying direction of the screw 5.

As shown in fig. 1-2, in one embodiment, the adjusting table 3 includes a first sliding table 31, a second sliding table 32, a third sliding table 33, a universal inclination table 34 and a rotating sliding table 35 sequentially arranged from bottom to top, the first sliding table 31 is mounted on a sliding block 42, and the shooting mechanism 2 is mounted on an upper surface of the rotating sliding table 35, so that when the screw 5 drives the sliding block 42 to move, the first sliding table 31, the second sliding table 32, the third sliding table 33, the universal inclination table 34, the rotating sliding table 35 and the shooting mechanism 2 all reciprocate along the laying direction of the screw 5 under the driving of the sliding block 42.

As shown in fig. 3 to 4, in one embodiment, the first sliding table 31 includes a first convex plate 311, a first sliding plate 312, a first rotating handle 313, a first connecting block 314, and a first mounting block 315, the first convex plate 311 is mounted on the sliding block 42, the first convex plate 311 is slidably connected with the first sliding plate 312, the first connecting block 314 is connected with the first convex plate 311, the first mounting block 315 is connected with the first sliding plate 312, the middle part of the first rotating handle 313 is screwed with the first connecting block 314, one end of the first rotating handle 313 is connected with the first mounting block 315, the second sliding table 32 includes a second rotating handle 321, a second connecting block 322, a second mounting block 323, and a second sliding plate 324, the second sliding plate 324 is slidably connected with the first sliding plate 312, the second connecting block 322 is connected with the first sliding plate 312, one end of the second rotating handle 321 is connected with the second mounting block 323, the second rotating handle 321 is vertically arranged with the first rotating handle 313, such that the first rotating handle 313 can move along the direction of the first sliding table 2, and the second sliding table 3 can move relative to the first sliding plate 312; the second sliding plate 324 and the first sliding plate 312 can slide relatively through the second rotating handle 321, and the adjusting table 3 can adjust the space position of the shooting mechanism 2, so that the shooting mechanism 2 can move along the X-axis direction.

As shown in fig. 3-5, in one embodiment, the third sliding table 33 includes a third rotating handle 331, a third mounting seat 332 and a third lifting plate 336, the third mounting seat 332 is connected with the second sliding plate 324, the third mounting seat 332 is provided with a groove 334 and a through hole 335, the through hole 335 is communicated with the groove 334, an L-shaped block 333 is provided in the groove 334, the L-shaped block 333 is rotatably connected with an inner wall of the groove 334, the third rotating handle 331 is connected with one end of the L-shaped block 333 through the through hole 335, the other end of the L-shaped block 333 is connected with the third lifting plate 336, so that by pushing the third rotating handle 331, the through hole 335 can guide the third rotating handle 331, and further, the third rotating handle 331 can push one end of the L-shaped block 333, and the third lifting plate 336 are rotatably connected through the other end of the L-shaped block 333, and when the third rotating handle 331 pushes one end of the L-shaped block 333, the other end of the L-shaped block 333 is abutted against the third lifting plate 336, and further the third lifting plate 336 can perform lifting movement, namely, the adjusting mechanism 3 can adjust the spatial position of the photographing mechanism 2 along the direction of the photographing axis.

As shown in fig. 6-8, in one embodiment, the universal tilt table 34 includes a push rod 341, a tilt seat 342, a connection plate 343, a connection rod 344 and balls 345, a placement channel 3421 is disposed in the tilt seat 342, one end of the connection rod 344 is abutted to the connection plate 343, the other end of the connection rod 344 is located in the placement channel 3421, the push rod 341 is connected with the connection rod 344 through the placement channel 3421, the balls 345 are located between the tilt seat 342 and the connection plate 343, the tilt seat 342 is mounted on the upper surface of the third lifting plate 336, the connection plate 343 is connected with the rotary sliding table 35, so, when a measurer pushes the push rod 341, the placement channel 3421 in the tilt seat 342 can guide the push rod 341, and meanwhile, one end of the connection rod 344 is abutted to the connection plate 343 through the placement channel 3421, so that when the push rod 341 is pushed, the connection rod 344 can be connected with the connection plate 343 through the placement channel 3421, and then the connection plate 343 is tilted, and meanwhile the rotary sliding table 35 is tilted along with the connection plate, namely, the spatial position of the adjusting table 3 can be adjusted along with the rotation of the photographing mechanism 2, and the photographing mechanism 2 is mounted on the rotary sliding table 35 along with the photographing mechanism 35.

In one embodiment, as shown in fig. 11, the base 6 is provided with a sliding groove 61, and the container 71 is slidably connected with the sliding groove 61, so that the position of the container 71 can be conveniently adjusted, and the photographing mechanism 2 can photograph.

Preferably, the container 71 is an oil bath, a glass window for observing the internal condition of the container 71 is arranged on one side of the container 71 close to the shooting mechanism 2, and an opening is arranged at the top end of the container 71.

In one embodiment, as shown in FIG. 11, the displacement sensor 72 is provided with an extension stem 721, the extension stem 721 being adapted to be coupled to the surface of the sample such that the displacement sensor 72 can measure the deformation of the sample via the extension stem 721.

As shown in fig. 10-11, in one embodiment, the detection mechanism 7 further includes a lifting frame 73, and the displacement sensor 72 is mounted on the lifting frame 73, while the lifting frame 73 is connected to the adjusting mechanism 8, so that the position of the detection mechanism 7 can be conveniently adjusted by the lifting frame 73, and the subsequent replacement of the sample in the container 71 is facilitated.

Preferably, adjustment mechanism 8 includes runner 81, lifting seat 82 and lifter 83, and crane 73 is connected with lifting seat 82, and runner 81 is connected with lifter 83, and lifter 83 and lifting seat 82 spiro union, so, when the measurement personnel rotated runner 81, runner 81 can drive lifter 83 rotation, and then lifter 83 can drive lifting seat 82 and go up and down, is connected with lifting seat 82 through crane 73, realizes that lifting seat 82 can drive detection mechanism 7 and go up and down.

The working principle of the utility model is as follows: the height position of the container 71 needs to be matched with the position of the lens of the photographing mechanism 2. Firstly, placing a lens of a shooting mechanism 2 on an adjusting table 3, then sliding the lens with a sliding groove 61 through a container 71, adjusting the height of the container 71 to correspond to the height of the lens of the shooting mechanism 2 placed on the adjusting table 3, and adjusting the position of a detection mechanism 7 through a lifting frame 73 after placing a sample in the container 71, so that the position of a displacement sensor 72 is positioned right above the sample; filling silicone oil into the container 71, rotating the hand wheel 41, and lightly pressing the extension rod 721 of the displacement sensor 72 to the surface of the sample to be measured; after the photographing mechanism 2 is opened and the hand wheel 41 is rotated to adjust the lens of the photographing mechanism 2 to the vicinity of the working position, focusing is performed by the combined adjustment of the first sliding table 31, the second sliding table 32, the third sliding table 33, the universal inclination table 34 and the rotary sliding table 35, the angle is leveled, and after the adjustment of the rotation angle, the photographing mechanism 2 can clearly photograph the sample condition in the container 71, and the measurement process is started.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the utility model, which are described in detail and are not to be construed as limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model. Accordingly, the scope of protection of the present utility model is to be determined by the appended claims.

Claims

1. The piezoelectric ceramic deformation measuring device comprises a mounting frame and is characterized by further comprising an adjusting seat mounted on the mounting frame, wherein one end of the adjusting seat is provided with a base, the other end of the adjusting seat is provided with a hand wheel, the base is mounted on the mounting frame, the adjusting seat is provided with a screw and an adjusting table screwed with the screw, the hand wheel is connected with the screw, the adjusting table is provided with a shooting mechanism, the adjusting table is used for adjusting the space position of the shooting mechanism, the adjusting seat is used for adjusting the position of the adjusting table, the base is provided with a detecting mechanism and an adjusting mechanism, the detecting mechanism comprises a container and a displacement sensor, the container is mounted on the base, the displacement sensor is connected with the adjusting mechanism, the adjusting mechanism is mounted on the base, and the visual range of the shooting mechanism covers the container.

2. The piezoelectric ceramic deformation measurement device according to claim 1, wherein the adjustment base includes a slider connected to a screw, and the adjustment table is mounted to the slider.

3. The piezoelectric ceramic deformation measurement device according to claim 1, wherein the adjustment table comprises a first sliding table, a second sliding table, a third sliding table, a universal inclination table and a rotary sliding table which are sequentially arranged from bottom to top, the first sliding table is mounted on the sliding block, and the shooting mechanism is mounted on the upper surface of the rotary sliding table.

4. The piezoelectric ceramic deformation measurement device according to claim 3, wherein the first sliding table comprises a first convex plate, a first sliding plate, a first rotating handle, a first connecting block and a first mounting block, the first convex plate is mounted on the sliding block, the first convex plate is slidably connected with the first sliding plate, the first connecting block is connected with the first convex plate, the first mounting block is connected with the first sliding plate, the middle part of the first rotating handle is in threaded connection with the first connecting block, and one end of the first rotating handle is connected with the first mounting block.

5. The piezoelectric ceramic deformation measurement device according to claim 4, wherein the second sliding table comprises a second rotating handle, a second connecting block, a second mounting block and a second sliding plate, the second sliding plate is in sliding connection with the first sliding plate, the second connecting block is connected with the first sliding plate, the second mounting block is connected with the second sliding plate, the middle part of the second rotating handle is in threaded connection with the second connecting block, one end of the second rotating handle is connected with the second mounting block, and the second rotating handle is perpendicular to the first rotating handle.

6. The piezoelectric ceramic deformation measurement device according to claim 4, wherein the third sliding table comprises a third rotating handle, a third mounting seat and a third lifting plate, the third mounting seat is connected with the second sliding plate, the third mounting seat is provided with a groove and a through hole, the through hole is communicated with the groove, an L-shaped block is arranged in the groove and is rotationally connected with the inner wall of the groove, the third rotating handle is connected with one end of the L-shaped block through the through hole, and the other end of the L-shaped block is connected with the third lifting plate.

7. The piezoelectric ceramic deformation measurement device according to claim 6, wherein the universal tilt table comprises a push rod, a tilt seat, a connecting plate, a connecting rod and balls, a placement channel is arranged in the tilt seat, one end of the connecting rod is in butt joint with the connecting plate, the other end of the connecting rod is located in the placement channel, the push rod is connected with the connecting rod through the placement channel, the balls are located between the tilt seat and the connecting plate, the tilt seat is mounted on the upper surface of the third lifting plate, and the connecting plate is connected with the rotary sliding table.

8. The piezoelectric ceramic deformation measurement device according to claim 1, wherein the base is provided with a chute, and the container is slidably connected to the chute.

9. The piezoelectric ceramic deformation measurement device according to claim 1, wherein the displacement sensor is provided with an extension rod for connection with a sample surface.

10. The piezoelectric ceramic deformation measurement device according to claim 9, wherein the detection mechanism further comprises a lifter, the displacement sensor is mounted to the lifter, and the lifter is connected to the adjustment mechanism.