Patent application title:

TRIM TOOL

Publication number:

US20260168264A1

Publication date:
Application number:

19/424,946

Filed date:

2025-12-18

Smart Summary: A trim tool helps to measure and mark pieces of trim for windows or doors. It has three main parts: a sturdy base and two sliding pieces that can move along the base. There are also angular parts that can slide on the two moving pieces to adjust for different sizes. By sliding these parts, users can align the tool to match the size of the frame. This tool makes it easier to mark where to cut the trim so it fits perfectly. 🚀 TL;DR

Abstract:

A trim tool is described. One aspect includes a first rigid member, a second rigid member slidably attached to the first rigid member, and a third rigid member slidably attached to the first rigid member. The trim tool may include a first angular protrusion structure slidably attached to the second rigid member, and a second angular protrusion structure slidably attached to the third rigid member. The second rigid member and/or the third rigid member may be slid over the first rigid member to substantially align the trim tool to a size of a portion of a frame associated with a window or a door. At least one offset is configured via sliding the first angular protrusion structure and/or the second angular protrusion structure. The trim tool may be used to mark a trim piece to be cut to fit the portion of the frame.

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Classification:

E04F21/003 »  CPC main

Implements for finishing work on buildings for marking doors, windows or frames

E04F21/26 »  CPC further

Implements for finishing work on buildings for mounting staircases, e.g. tools for marking steps

E04F21/00 IPC

Implements for finishing work on buildings

Description

BACKGROUND

This application claims the priority benefit of provisional Ser. No. 63/735,489 titled “The Trim Stick” filed on Dec. 18, 2024, the disclosure of which is incorporated by reference herein in its entirety.

TECHNICAL FIELD

The present disclosure relates to trim tools for configuring trims for frames associated with doors, windows, or stair covers for stairways.

BACKGROUND ART

When windows and doors are installed, a trim covers the outside of the door or window frame. When custom trim parts are made there is a need to cut the trim parts precisely equal on the top and bottom and left and right sides. This is sometimes a challenge because the size of the trim is determined by measuring the window or door opening and then adding an offset from the edge of the frame to the inner edge of the trim. The offset varies in different applications from a positive offset to a negative offset where the trim extends inside the frame for a negative offset and outside the frame for a positive offset.

SUMMARY

Aspects of the invention are directed to a trim tool configured to provide measurements that can be used to cut a trim for a frame associated with a door or a window, or a stair cover for a stairway. In an aspect, the trim tool includes a first rigid member, a second rigid member slidably attached to the first rigid member, and a third rigid member slidably attached to the first rigid member. The trim tool may also include a first angular protrusion structure slidably attached to the second rigid member to configure a first offset, and a second angular protrusion structure slidably attached to the third rigid member to configure a second offset.

In an aspect, any combination of the second rigid member and the third rigid member is slid over the first rigid member to substantially align the trim tool to a size of a portion of a frame associated with a window or a door, or to a width of a stairway. At least one offset of the first offset and the second offset may be set via sliding any combination of the first angular protrusion structure and the second angular protrusion structure over the second rigid member and the third rigid member, respectively. The trim tool configured with the at least one offset can be used to mark a trim piece or a stair cover to be cut to fit the portion of the frame or the width of the stairway, respectively.

In an aspect, the second rigid member is configured to slide with respect to at least a portion of a first longitudinal half of the first rigid member, and the third rigid member is configured to slide with respect to at least a portion of a second longitudinal half of the first rigid member.

In one embodiment, each of the first offset and the second offset is set to be between −0.75 inch and 0.5 inch.

In an embodiment, each of the first offset and the second offset is configured in ⅛-inch increments.

In one aspect, each of the first angular protrusion structure and the second angular protrusion structure includes an angle of 45°.

In an embodiment, each of the first angular protrusion structure and the second angular protrusion structure includes an angle that is any of 30° and 60°.

Each of the first angular protrusion structure and the second angular protrusion structure may include an angle that is configurable to be at a value within a range of 0° to 90°. This angle may be configurable in increments of 5°.

In an aspect, sliding any combination of the second rigid member and the third rigid member to substantially align the trim tool to the size of the portion of the frame or the width of the stairway results in an adjustment of a length of the trim tool. The length of the trim tool can be adjusted to be between 21 inches and 41 inches and with additional members can be extended to 150 inches.

The trim tool may further include a distinct locking knob for each of the second rigid member, the third rigid member, the first angular protrusion structure, and the second angular protrusion structure. Each of the locking knobs may be configured to prevent a sliding motion of the second rigid member, the third rigid member, the first angular protrusion structure, and the second angular protrusion structure respectively, when the respective locking knob is tightened.

Other embodiments include methods that use the trim tool to perform measurements for a trim piece associated with a window frame or a door frame, or for a stair cover for a stairway.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the present disclosure are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various figures unless otherwise specified.

FIG. 1 is a schematic drawing illustrating a window frame and a window trim.

FIG. 2A is a front view of a trim tool.

FIG. 2B is a top view of a trim tool.

FIG. 2C is a rear view of a trim tool.

FIG. 2D is a view of a portion of a trim tool used to configure an offset.

FIG. 3 is a view depicting a trim tool being used to measure a portion of a window frame.

FIG. 4 is a view depicting a trim tool being used to mark a window trim piece.

FIG. 5 is a schematic diagram depicting three different views of a trim tool.

FIG. 6 is a view depicting a portion of a trim tool used to configure an offset.

FIG. 7 is a view of a portion of a trim tool depicting an angular protrusion structure.

FIG. 8 is a view of a portion of a trim tool depicting an angular protrusion structure.

FIG. 9 is a schematic drawing illustrating a use of a trim tool.

FIG. 10 is a schematic drawing illustrating a use of a trim tool to acquire a measurement for a stair cover.

FIG. 11 is a schematic drawing illustrating a use of a trim tool to mark a stair cover.

DETAILED DESCRIPTION

In the following description, reference is made to the accompanying drawings that form a part thereof, and in which is shown by way of illustration specific exemplary embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the concepts disclosed herein, and it is to be understood that modifications to the various disclosed embodiments may be made, and other embodiments may be utilized, without departing from the scope of the present disclosure. The following detailed description is, therefore, not to be taken in a limiting sense.

Reference throughout this specification to “one embodiment,” “an embodiment,” “one example,” or “an example” means that a particular feature, structure, or characteristic described in connection with the embodiment or example is included in at least one embodiment of the present disclosure. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” “one example,” or “an example” in various places throughout this specification are not necessarily all referring to the same embodiment or example. Furthermore, the particular features, structures, databases, or characteristics may be combined in any suitable combinations and/or sub-combinations in one or more embodiments or examples. In addition, it should be appreciated that the figures provided herewith are for explanation purposes to persons ordinarily skilled in the art and that the drawings are not necessarily drawn to scale.

Embodiments in accordance with the present disclosure may be embodied as an apparatus, method, or computer program product. Accordingly, the present disclosure may take the form of an entirely hardware-comprised embodiment, an entirely software-comprised embodiment (including firmware, resident software, micro-code, etc.), or an embodiment combining software and hardware aspects that may all generally be referred to herein as a “circuit,” “module,” or “system.” Furthermore, embodiments of the present disclosure may take the form of a computer program product embodied in any tangible medium of expression having computer-usable program code embodied in the medium.

Any combination of one or more computer-usable or computer-readable media may be utilized. For example, a computer-readable medium may include one or more of a portable computer diskette, a hard disk, a random-access memory (RAM) device, a read-only memory (ROM) device, an erasable programmable read-only memory (EPROM or Flash memory) device, a portable compact disc read-only memory (CDROM), an optical storage device, a magnetic storage device, and any other storage medium now known or hereafter discovered. Computer program code for carrying out operations of the present disclosure may be written in any combination of one or more programming languages. Such code may be compiled from source code to computer-readable assembly language or machine code suitable for the device or computer on which the code can be executed.

Embodiments may also be implemented in cloud computing environments. In this description and the following claims, “cloud computing” may be defined as a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned via virtualization and released with minimal management effort or service provider interaction and then scaled accordingly. A cloud model can be composed of various characteristics (e.g., on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured service), service models (e.g., Software as a Service (“SaaS”), Platform as a Service (“PaaS”), and Infrastructure as a Service (“IaaS”)), and deployment models (e.g., private cloud, community cloud, public cloud, and hybrid cloud).

The flow diagrams and block diagrams in the attached figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flow diagrams or block diagrams may represent a module, segment, or portion of code, which includes one or more executable instructions for implementing the specified logical function(s). It is also noted that each block of the block diagrams and/or flow diagrams, and combinations of blocks in the block diagrams and/or flow diagrams, may be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions. These computer program instructions may also be stored in a computer-readable medium that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable medium produce an article of manufacture including instruction means which implement the function/act specified in the flow diagram and/or block diagram block or blocks.

The trim tool described herein enables easy, accurate and consistent measuring and marking of trim parts to be affixed on window frames or door frames.

FIG. 1 is a schematic drawing 100 illustrating a window frame 102 and a window trim 106, as a portion of a window. In contemporary construction, a precise measurement of an offset 104 is needed in order to appropriately configure/cut trim 106 to the dimensions of window frame 102. This offset may be a positive offset or a negative offset. The associated measurement workflow applies to construction processes for doors as well. The trim tool described herein enables a precise configuration of a desired offset based on measurements of a portion (e.g., top, bottom, left or right portion) of a frame associated with a window. This offset can then be used to mark and cut a trim piece to fit with that portion of the frame. Generally, a trim includes four trim pieces for a rectangular-shaped window frame and three pieces for a door frame.

FIG. 2A is a front view of a trim tool 200. As depicted, trim tool 200 includes a rigid member 218, a rigid member 214, a rigid member 216, an angular protrusion structure 210, an angular protrusion structure 212, a locking knob 202, a locking knob 206, a locking knob 208, and a locking knob 204.

In an aspect, rigid member 214 is slidably connected to rigid member 218, on at least a portion of a first longitudinal half of rigid member 218. As depicted in front view 200, rigid member 214 can slide to the left or to the right with respect to at least a portion of a left half of rigid member 218. Rigid member 214 can be secured to rigid member 218 using locking knob 206. Tightening locking knob 206 prevents rigid member 214 from sliding with respect to rigid member 218. Conversely, loosening locking knob 206 enables rigid member 214 to slide with respect to rigid member 218.

In an aspect, rigid member 216 is slidably connected to rigid member 218, on at least a portion of a second longitudinal half of rigid member 218. As depicted in front view 200, rigid member 216 can slide to the left or to the right with respect to at least a portion of a right half of rigid member 218. Rigid member 216 can be secured to rigid member 218 using locking knob 208. Tightening locking knob 208 prevents rigid member 216 from sliding with respect to rigid member 218. Conversely, loosening locking knob 208 enables rigid member 216 to slide with respect to rigid member 218.

In an aspect, angular protrusion structure 210 is slidably connected to rigid member 214. As depicted in front view 200, angular protrusion structure 210 is connected to a left-hand side of rigid member 214, and can slide to the left or to the right with respect to rigid member 214. Angular protrusion structure 210 can be secured to rigid member 214 using locking knob 202. Tightening locking knob 202 prevents angular protrusion structure 210 from sliding with respect to rigid member 214. Conversely, loosening locking knob 202 enables angular protrusion structure 210 to slide with respect to rigid member 214.

In an aspect, angular protrusion structure 212 is slidably connected to rigid member 216. As depicted in front view 200, angular protrusion structure 212 is connected to a right-hand side of rigid member 216, and can slide to the left or to the right with respect to rigid member 216. Angular protrusion structure 212 can be secured to rigid member 216 using locking knob 204. Tightening locking knob 204 prevents angular protrusion structure 212 from sliding with respect to rigid member 216. Conversely, loosening locking knob 204 enables angular protrusion structure 212 to slide with respect to rigid member 216.

FIG. 2B is a top view of trim tool 200. This view shows angular protrusion structures 210 and 212, locking knobs 202 and 204, and rigid members 214, 216, and 218.

FIG. 2C is a rear view of trim tool 200. This view shows angular protrusion structures 210 and 212, locking knobs 206 and 208, and rigid members 214, 216, and 218.

FIG. 2D is a view of a portion of trim tool 200 used to configure an offset 220. To configured offset 220, a user may loosen locking knob 202 and slide angular protrusion structure 210 to the left or to the right, relative to rigid member 214, to configure a width of offset 220.

FIG. 3 is a view 300 depicting trim tool 200 being used to measure a portion of a window frame 302. To perform this measurement, initially locking knobs 202 and 204 are tightened to prevent any motion of angular protrusion structures 210 and 212 with respect to rigid members 214 and 216, respectively. Then, trim tool 200 is positioned to be substantially parallel to and adjacent to a selected edge of window frame 302. For example, trim tool 200 may be positioned to be parallel to and adjacent to a top edge, a bottom edge, a left edge, or a right edge of window frame 302 (FIG. 3 depicts trim tool 200 being positioned parallel to and adjacent to a top edge of the window frame 302). Then, any combination of locking knobs 206 and 208 is loosened (if they are previously tightened), and any respective combination of rigid members 214 and 216 is slid with respect to rigid member 218, such that a length of trim tool 200 (from a left edge of angular protrusion structure 210 to a right edge of angular protrusion structure 212 as viewed from front) is substantially equal to a length of the selected edge of window frame 302. Any of locking knobs 206 and 208 that are loosened are then tightened.

Next, any combination of locking knobs 202 and 204 is loosened and a respective combination of angular protrusion structures 210 and 212 is slid relative to rigid members 214 and 216, respectively, to configure respective offsets associated with angular protrusion structures 210 and 212. Any of locking knobs 202 and 204 that are loosened are then tightened. Trim tool 200 is now configured with a measurement of the selected edge of window frame 302, along with a desired offset that is a combination of the offsets associated with angular protrusion structures 210 and 212.

FIG. 4 is a view 400 depicting trim tool 200 being used to mark a window trim piece 402. The trim tool 200 configured as shown in FIG. 3 can then be placed on a window trim piece 402 to be substantially parallel to and adjacent to window trim piece 402. as shown in view 400. The window trim 402 can be marked and then cut (or directly cut) in accordance with the angular structure associated with angular protrusion structures 210 and 212, as depicted in view 400. The trim tool can similarly be used to prepare trim pieces for doors.

In an aspect, an angle associated with each of angular protrusion structures 210 and 212 is 45°. This enables adjacent trim pieces from perpendicular edges of a door or window frame to be properly joined together at a right angle (based on the geometrical topology). In an aspect, offset 220 can be set on trim tool 200 in a range of −0.75 inch to +0.5 inch. In an aspect, offset 220 can be set in ⅛ inch increments. In an aspect, locking knobs 206 and 208 can be used to change a length of trim tool 200 in a range of 21 inches to 40 inches, allowing trim tool 200 to be used to configure trim pieces for doors or windows in the range of 21 inches to 40 inches.

In other embodiments of trim tool 200, an extension adapter can be added to trim tool 200, to enable trim tool 200 to be used with window frames or door frames of longer lengths. For example, an adapter may be of a length of 24 inches or 36 inches. This extends the upper range of measurement to 64 inches, or 76 inches, respectively. In another embodiment, an extension adapter can enable a maximum extension length of 150 inches for trim tool 200.

In the embodiment of trim tool 200 depicted in FIGS. 2A through 2C, angular protrusion structures 210 and 212 are associated with an angle of 45°. In other embodiments, angular protrusion structures 210 and 212 may be replaceable parts of trim tool 200, being replaceable with angular protrusion structures having other angular measurements, such as 30° or 60°. For example, angular protrusion structure 210 may be replaced by an angular protrusion structure associated with an angle of 30°, while angular protrusion structure 212 may be replaced by an angular protrusion structure associated with an angle of 60°. Then, when a trim piece is cut, one end is cut at an angle of 30°, and the other end is cut at an angle of 60°. When assembling the trim around the frame, the 30° end of the trim piece mates with the 60° end of an adjacent trim piece, while the 60° end of the trim mates with the 30° end of another adjacent trim piece, thereby preserving orthogonality of all adjacent trim pieces.

In another embodiment, any or both of angular protrusion structures 210 and 212 is can be configured with an angle in range 0° to 90°. In this case, the angle may be configurable in increments of 5°.

In an aspect, different (configurable/adjustable) angles for angular protrusion structures 210 and 212 can be used in the following cases:

    • If different width trim material is used,
    • If the window is not square. For example if the window is a hexagon shape the angle for the trim should be 60 degrees, if the window is triangular the cutting angle should be 30 degrees and if the window is an octagon the angle should be 67.5 degrees. An example of an angular protrusion structure with a configurable/adjustable angle is depicted in FIG. 7.

FIG. 5 is a schematic diagram 500 depicting three different views of a trim tool—a front view, a rear view and a three-quarter view (as viewed from top to bottom in FIG. 5). The trim tool depicted in FIG. 5 is an alternate embodiment of trim tool 200. The trim tool depicted in FIG. 5 differs from trim tool 200 in at least the following ways:

    • The angular protrusion structures 210 and 212 are enlarged,
    • Each triangular protrusion structure of the trim tool depicted in FIG. 5 includes a triangular cutout for weight reduction.

FIG. 6 is a view 600 depicting a portion of a trim tool from FIG. 5, used to configure an offset. This trim tool includes locking knobs 604 and 606, equivalent in function to locking knobs 202 and 206, respectively. The offset 602 can be accurately measured and set via a calibrated scale as shown in view 600.

FIG. 7 is a view 700 of a portion of a trim tool depicting an angular protrusion structure 702. As depicted, an angle associated with angular protrusion structure can be adjusted via knob 704, to configure/adjust the angle associated with the angular protrusion structure (as described earlier).

FIG. 8 is a view 800 of a portion of a trim tool depicting an angular protrusion structure 802. Angular protrusion structure 802 has a triangular cutout 804 for weight reduction, as described earlier.

FIG. 9 is a schematic drawing 900 illustrating a use of a trim tool 904. As shown, a user uses trim tool 904 to measure a portion of a door frame 902, using the workflow described earlier.

FIG. 10 is a schematic drawing 1000 illustrating a use of a trim tool 1002 to acquire a measurement for a stair cover. In addition to measuring portions of door frames or window frames, a trim tool as described herein (e.g., trim tool 1002) can be used to measure a width of a stairway, as shown in FIG. 10. Then, an appropriate offset can be set on trim tool 1002, using a workflow similar to that used to set an offset on a trim tool for marking a door frame or a window frame.

FIG. 11 is a schematic drawing 1100 illustrating a use of trim tool 1002 to mark a stair cover. Once the offset associated with the stairway is set on trim tool 1002 (as described above), trim tool 1002 can be used to mark a width of a stair cover for cutting, as depicted in FIG. 11. In this case, instead of the angular portion of the angular protrusion structure to perform the marking, the straight vertical edge of each angular protrusion structure is used to mark the stair cover.

Although the present disclosure is described in terms of certain example embodiments, other embodiments will be apparent to those of ordinary skill in the art, given the benefit of this disclosure, including embodiments that do not provide all of the benefits and features set forth herein, which are also within the scope of this disclosure. It is to be understood that other embodiments may be utilized, without departing from the scope of the present disclosure.

Claims

What is claimed is:

1. A trim tool comprising:

a first rigid member;

a second rigid member slidably attached to the first rigid member;

a third rigid member slidably attached to the first rigid member;

a first angular protrusion structure slidably attached to the second rigid member to configure a first offset; and

a second angular protrusion structure slidably attached to the third rigid member to configure a second offset, wherein:

any combination of the second rigid member and the third rigid member is slid over the first rigid member to substantially align the trim tool to a size of a portion of a frame associated with a window or a door, or to a width of a stairway;

at least one offset of the first offset and the second offset is configured via sliding any combination of the first angular protrusion structure and the second angular protrusion structure over the second rigid member and the third rigid member, respectively; and

the trim tool configured with the at least one offset is used to mark a trim piece or a stair cover to be cut to fit the portion of the frame or the width of the stairway, respectively.

2. The trim tool of claim 1, wherein:

the second rigid member is configured to slide with respect to at least a portion of a first longitudinal half of the first rigid member; and

the third rigid member is configured to slide with respect to at least a portion of a second longitudinal half of the first rigid member.

3. The trim tool of claim 1, wherein each of the first offset and the second offset is set to be between −0.75 inch and 0.5 inch.

4. The trim tool of claim 1, wherein each of the first offset and the second offset is configured in ⅛-inch increments.

5. The trim tool of clam 1, wherein each of the first angular protrusion structure and the second angular protrusion structure includes an angle of 45°.

6. The trim tool of claim 1, wherein each of the first angular protrusion structure and the second angular protrusion structure includes an angle that is any of 30° and 60°.

7. The trim tool of claim 1, wherein each of the first angular protrusion structure and the second angular protrusion structure includes an angle that is configurable to be at a value within a range of 0° to 90°.

8. The trim tool of claim 7, wherein the angle is configurable in increments of 5°.

9. The trim tool of claim 1, wherein sliding any combination of the second rigid member and the third rigid member to substantially align the trim tool to the size of the portion of the frame or the width of the stairway results in an adjustment of a length of the trim tool.

10. The trim tool of claim 9, wherein the length of the trim tool can be adjusted to be between 21 inches and 41 inches.

11. The trim tool of claim 10, further comprising one or more extension adapters that enable a maximum length of the trim tool to be 64 inches, 76 inches, or 150 inches.

12. The trim tool of claim 1, further comprising a distinct locking knob for each of the second rigid member, the third rigid member, the first angular protrusion structure, and the second angular protrusion structure, wherein each of the locking knobs is configured to prevent a sliding motion of the second rigid member, the third rigid member, the first angular protrusion structure, and the second angular protrusion structure respectively, when the respective locking knob is tightened.

13. A method comprising:

providing a trim tool comprising:

a first rigid member;

a second rigid member slidably attached to the first rigid member;

a third rigid member slidably attached to the first rigid member;

a first angular protrusion structure slidably attached to the second rigid member to configure a first offset; and

a second angular protrusion structure slidably attached to the third rigid member to configure a second offset;

sliding any combination of the second rigid member and the third rigid member over the first rigid member to substantially align the trim tool to a size of a portion of a frame associated with a window or a door, or to a width of a stairway;

sliding any combination of the first angular protrusion structure and the second angular protrusion structure over the second rigid member and the third rigid member, respectively to configure at least one offset of the first offset and the second offset; and

marking a trim piece or a stair cover to be cut to fit the portion of the frame or the width of the stairway, respectively, using the trim tool configured with the at least one offset.

14. The method of claim 13, wherein:

the second rigid member is configured to slide with respect to at least a portion of a first longitudinal half of the first rigid member; and

the third rigid member is configured to slide with respect to at least a portion of a second longitudinal half of the first rigid member.

15. The method of claim 13, wherein each of the first offset and the second offset is set to be between −0.75 inch and 0.5 inch.

16. The method of claim 13, wherein each of the first offset and the second offset is configured in ⅛-inch increments.

17. The method of clam 13, wherein each of the first angular protrusion structure and the second angular protrusion structure includes an angle of 45°.

18. The method of claim 13, wherein each of the first angular protrusion structure and the second angular protrusion structure includes an angle that is any of 30° and 60°.

19. The method of claim 13, wherein each of the first angular protrusion structure and the second angular protrusion structure includes an angle that is configurable to be at a value within a range of 0° to 90°.

20. The method of claim 19, wherein the angle is configurable in increments of 5°.

21. The method of claim 13, wherein sliding any combination of the second rigid member and the third rigid member to substantially align the trim tool to the size of the portion of the frame or the width of the stairway results in an adjustment of a length of the trim tool.

22. The method of claim 21, wherein the length of the trim tool can be adjusted to be between 21 inches and 41 inches.

23. The method of claim 22, further comprising one or more extension adapters that enable a maximum length of the trim tool to be 64 inches or 76 inches.

24. The method of claim 13, further comprising a distinct locking knob for each of the second rigid member, the third rigid member, the first angular protrusion structure, and the second angular protrusion structure, wherein each of the locking knobs is configured to prevent a sliding motion of the second rigid member, the third rigid member, the first angular protrusion structure, and the second angular protrusion structure respectively, when the respective locking knob is tightened.