CN217453826U - Tool for improving safety and work efficiency of edge-facing hole opening operation - Google Patents

Tool for improving safety and work efficiency of edge-facing hole opening operation Download PDF

Info

Publication number
CN217453826U
CN217453826U CN202221055659.3U CN202221055659U CN217453826U CN 217453826 U CN217453826 U CN 217453826U CN 202221055659 U CN202221055659 U CN 202221055659U CN 217453826 U CN217453826 U CN 217453826U
Authority
CN
China
Prior art keywords
tool
support member
safety
improving
pressing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202221055659.3U
Other languages
Chinese (zh)
Inventor
洪颜昊
马超晨
王永强
陈斌
范延松
周扬
刘健飞
郭皓
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Electric Engineering Co Ltd of China Railway 19th Bureau Group Co Ltd
Original Assignee
Electric Engineering Co Ltd of China Railway 19th Bureau Group Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Electric Engineering Co Ltd of China Railway 19th Bureau Group Co Ltd filed Critical Electric Engineering Co Ltd of China Railway 19th Bureau Group Co Ltd
Priority to CN202221055659.3U priority Critical patent/CN217453826U/en
Application granted granted Critical
Publication of CN217453826U publication Critical patent/CN217453826U/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Drilling And Boring (AREA)

Abstract

The utility model relates to a construction technical field especially relates to a tool of edge trompil operation security and work efficiency is faced in improvement. The tool comprises a workbench, wherein a clamping assembly is arranged at one end of the workbench, a tool seat is arranged on the workbench, the tool seat is in sliding fit with the workbench, and a pushing rod extending to the ground is arranged on one side, away from a clamping component, of the tool seat. The utility model provides an instrument is connected this device and the lower extreme of the roof beam body of eminence operation position department through the centre gripping subassembly, is connected operation instrument and tool holder, and the operation personnel can pass through the pushing ram on ground and impel the tool holder to being close to the position of waiting to be under construction, realizes treating the operation at the position of being under construction, has effectively avoided the operation personnel to cause the uncomfortable and tired in the long-time same angle operation of eminence, has improved the security of eminence operation. Moreover, the device has small volume, so that the problem that space limitation is caused to personnel for operation inconvenience during high-altitude operation is solved, and the difficulty of high-altitude operation is reduced.

Description

Tool for improving safety and work efficiency of edge-facing hole opening operation
Technical Field
The utility model relates to a construction technical field especially relates to a tool of edge trompil operation security and work efficiency is faced in improvement.
Background
The subway electromechanical and shield door installation and construction process involves more high-altitude drilling projects such as electric hammers and electric drills, and the high-altitude side facing operation process is sometimes inconvenient to operate by space-limited personnel, or causes discomfort to personnel due to long-time operation at the same angle, and safety accidents are easily caused due to fatigue in the construction process.
SUMMERY OF THE UTILITY MODEL
In order to solve the technical problem, the present disclosure provides a tool for improving safety and work efficiency of the edge drilling operation.
The utility model provides an improve and face instrument of limit trompil operation security and work efficiency, include: the one end of workstation is provided with the centre gripping subassembly that is used for the centre gripping roof beam body, be provided with the instrument seat that is used for fixed operation instrument on the workstation, the instrument seat with workstation sliding fit, the instrument seat is kept away from one side of hold assembly is provided with the impulse lever that extends to ground.
Optionally, the clamping assembly includes a frame body, a pressing plate and an adjusting assembly, the frame body includes a first side plate, the pressing plate is disposed in the frame body and opposite to the first side plate, a beam clamping space is formed between the first side plate and the pressing plate, and the adjusting assembly is used for adjusting the position of the pressing plate to adjust the size of the beam clamping space.
Optionally, the frame body includes the second curb plate, adjusting part includes threaded rod and adjustment handle, the threaded rod with second curb plate screw-thread fit, and one end pass the second curb plate with the clamp plate is connected, the other end with adjustment handle connects.
Optionally, a slide rail is arranged on the workbench, and the tool holder is slidably connected with the slide rail.
Optionally, the tool holder comprises a first support member for supporting a front end of the work tool and a second support member for supporting a rear end of the work tool, the first support member and the second support member being detachably connected.
Optionally, the first supporting part comprises a supporting platform far away from one end of the workbench, and the supporting platform extends towards the direction far away from the second supporting part along the direction parallel to the workbench.
Optionally, the supporting platform is provided with a first opening for being in plug-in fit with a front end handle of the working tool.
Optionally, a pressing member for pressing a switch of the work tool is provided on a side of the second support member facing the first support member.
Optionally, the push rod is hinged to the second support member.
Optionally, the pressing member includes a connecting portion and a pressing portion, the connecting portion is disposed coaxially with the push rod and passes through the second support member to be connected with the push rod, and the pressing portion is bent with respect to the connecting portion to press the switch of the working tool.
The technical scheme provided by the disclosure has the following advantages:
in the tool for improving the safety and the work efficiency of the edge-facing hole opening operation, the tool is fixedly clamped with the beam body through the clamping assembly so as to be connected with the beam body; placing a working tool on the tool seat, and fixing and limiting the working tool through the tool seat so as to connect the working tool with the device; the tool holder slides and sets up on the workstation, and the workstation has played the supporting role to tool holder and operation instrument, through tool holder and workstation sliding connection, adjustable operation instrument's position. Need when the eminence operation, be connected this device with the lower extreme of the roof beam body of eminence operation position department through the centre gripping subassembly, be connected working tool and instrument seat, and treat the construction position with working tool's operation end and roof beam body top and aim at, the operation personnel can pass through the pushing ram on ground with the instrument seat to being close to and treat the propulsion of construction position, the operation at the construction position is treated in the realization, effectively avoided the operation of operation personnel to cause the health discomfort and fatigue at the long-time same angle operation of eminence, and can satisfy the operation personnel and treat the construction position and carry out the operation keeping away from the position that faces the limit, the security of eminence operation has been improved. Moreover, the device has small volume, solves the problem that the operation of high-altitude operation is inconvenient for space-limited personnel, reduces the difficulty of the high-altitude operation, and simultaneously improves the efficiency of the high-altitude operation.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and together with the description, serve to explain the principles of the disclosure.
In order to more clearly illustrate the embodiments or technical solutions in the prior art of the present disclosure, the drawings used in the description of the embodiments or prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive exercise.
FIG. 1 is a schematic view of one configuration of a tool for improving the safety and ergonomics of a near edge hole opening operation according to an embodiment of the present disclosure;
FIG. 2 is a schematic view of another configuration of a tool for improving the safety and ergonomics of a near-edge hole opening operation according to an embodiment of the present disclosure.
Wherein, 1, clamping the assembly; 11. a frame body; 12. pressing a plate; 13. a threaded rod; 14. an adjusting handle; 2. a work table; 3. a tool holder; 31. a first support member; 32. a second support member; 33. a support platform; 34. a first opening; 35. a pressing member; 36. a connecting rod; 37. a nut; 4. a slide rail; 5. a push rod; 6. a mounting base; 7. a screw; 10. a work tool.
Detailed Description
In order that the above objects, features and advantages of the present disclosure may be more clearly understood, aspects of the present disclosure will be further described below. It should be noted that the embodiments and features of the embodiments of the present disclosure may be combined with each other without conflict.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure, but the present disclosure may be practiced in other ways than those described herein; it is to be understood that the embodiments disclosed in the specification are only a few embodiments of the present disclosure, and not all embodiments.
As shown in fig. 1 to 2, the present disclosure provides a tool for improving safety and efficiency of an edge drilling operation, including: workstation 2, the one end of workstation 2 is provided with the centre gripping subassembly 1 that is used for the centre gripping roof beam body, is provided with the instrument seat 3 that is used for fixed operation instrument 10 on the workstation 2, instrument seat 3 and workstation 2 sliding fit, and one side that the clamping part was kept away from to instrument seat 3 is provided with the propulsion pole 5 that extends to ground.
In the tool for improving the safety and the work efficiency of the edge-facing hole opening operation, the clamping component 1 is clamped and fixed with the beam body so as to connect the tool with the beam body; placing the working tool 10 on the tool seat 3, and fixing and limiting the working tool 10 through the tool seat 3 so as to connect the working tool 10 with the device; the tool base 3 is arranged on the workbench 2 in a sliding mode, the workbench 2 supports the tool base 3 and the working tool 10, and the position of the working tool 10 can be adjusted through the sliding connection of the tool base 3 and the workbench 2. Need when the eminence operation, be connected this device with the lower extreme of the roof beam body of eminence operation position department through centre gripping subassembly 1, be connected operation instrument 10 and tool holder 3, and treat the construction position with operation instrument 10's operation end and roof beam body top and aim at, the operation personnel can pass through push rod 5 on ground and impel tool holder 3 to being close to the position of treating the construction, the operation at the position of treating the construction position is realized treating, effectively avoided the operation personnel to cause the health discomfort and fatigue at the long-time same angle operation of eminence, and can satisfy the operation personnel and treat the construction position and carry out the operation keeping away from the position of facing the limit, the security of eminence operation has been improved. Moreover, the device has small volume, solves the problem that the operation of high-altitude operation is inconvenient for space-limited personnel, reduces the difficulty of the high-altitude operation, and simultaneously improves the efficiency of the high-altitude operation.
The work tool 10 may be an electric drill, an electric pick, or an electric hammer. Taking the working tool 10 as an example of an electric drill, the electric drill is fixed at a high-altitude working position through the device, an operator pushes the tool base 3 to move to a part to be constructed through the push rod 5 on the ground, and after the operation is finished, the push rod 5 applies force in a direction away from a beam body, so that the working tool 10 is separated from the working position above the beam body.
Specifically, a slide rail 4 is arranged on the workbench 2, and the tool holder 3 is slidably connected with the slide rail 4. The slide rail 4 is arranged on the workbench 2, so that the movement track of the tool base 3 is limited, and in the process of pushing the tool base 3 to perform operation on the part to be constructed, the slide rail 4 can effectively ensure that the operation tool 10 operates according to the preset operation track, and the operation accuracy is improved.
In some embodiments, the tool holder 3 includes a first support member 31 for supporting the work tool 10 and a second support member 32 for supporting the work tool 10, and the first support member 31 and the second support member 32 are detachably connected.
That is, the tool rest 3 includes the first supporting part 31 and the second supporting part 32 which are sequentially arranged along the direction of the slide rail 4, the first supporting part 31 and the second supporting part 32 are detachably connected, that is, the distance between the first supporting part 31 and the second supporting part 32 is adjustable, so that the tool rest 3 can be adapted to a variety of work tools 10, and the first supporting part 31 and the second supporting part 32 are connected and fixed after the work tool 10 is placed on the tool rest 3, so that the work tool 10 can be clamped between the first supporting part 31 and the second supporting part 32, and the stability of the fit between the work tool 10 and the tool rest 3 is improved.
Specifically, the bottom of the first support part 31 is provided with a connecting rod 36, the free end of the connecting rod 36 is provided with a threaded section, the bottom of the second support part 32 is provided with a through hole, and when the first support part 31 and the second support part 32 are connected, the part of the connecting rod 36 provided with the threaded section passes through the through hole and is screwed by a nut 37.
In particular, the first support part 31 comprises a support platform 33 arranged at an end remote from the table 2, the support platform 33 extending in a direction away from the second support part in a direction parallel to the table 2.
That is, the support platform 33 is provided on the first support member 31 to support the front end of the work tool 10, thereby improving the stability of the engagement between the work tool 10 and the tool rest 3.
Specifically, the supporting platform 33 is provided with a first opening 34 for inserting and matching with a front end handle of the working tool 10.
The working tool 10 is provided with a front end handle, a middle handle and a rear end handle, for example, the working tool 10 is an electric drill, an electric pick or an electric hammer, and the three working tools 10 are provided with a front end handle, a middle handle and a rear end handle. When the work tool 10 is fixed by the tool rest 3, the front end handle of the work tool 10 is inserted into the first opening 34, the middle handle and the rear end handle are located between the first support member 31 and the second support member 32, and the rear end handle is abutted against one side of the second support member 32 by adjusting the distance between the first support member 31 and the second support member 32, so that the matching limit of the work tool 10 and the tool rest 3 is realized.
In some embodiments, each of the first support member 31 and the second support member 32 may include a telescopic structure and a locking structure to adjust a height dimension of each of the first support member 31 and the second support member 32, thereby adjusting a distance between the work tool 10 and the work table 2 to perform operations on various portions to be constructed.
Specifically, as shown in fig. 2, the first support member 31 may include a first sleeve and a second sleeve, at least a portion of the second sleeve being disposed within the first sleeve, and the second support member 32 includes a third sleeve and a fourth sleeve, at least a portion of the fourth sleeve being disposed within the third sleeve. The first sleeve and the third sleeve are respectively provided with two positioning holes, and the two positioning holes are oppositely arranged relative to the axis; two sets of positioning holes are formed in the second sleeve and the fourth sleeve, the two sets of positioning holes are arranged relative to the axis, each set of positioning holes comprises a plurality of positioning holes, and the plurality of positioning holes are evenly arranged along the axis at intervals. When adjusting the height of first supporting part 31, adjust the relative position of first sleeve and second sleeve, then pass first telescopic locating hole and second telescopic locating hole through the screw to lock through the nut, realize first telescopic and second telescopic spacing. When the height of the first supporting member 31 is adjusted, the height of the first supporting member 31 can be adjusted by adjusting the matching of the positioning hole of the first sleeve and the different positioning holes of the second sleeve. Similarly, when the height of the second supporting member 32 is adjusted, the relative positions of the third sleeve and the fourth sleeve are adjusted, then the screws penetrate through the positioning holes of the third sleeve and the positioning holes of the fourth sleeve, and the third sleeve and the fourth sleeve are locked by the nuts, so that the third sleeve and the fourth sleeve are limited. When the height of the second supporting part 32 is adjusted, the height of the second supporting part 32 can be adjusted by adjusting the matching of the positioning hole of the third sleeve and the different positioning holes of the fourth sleeve.
Or, when the first sleeve and the second sleeve, and the third sleeve and the fourth sleeve are adjusted to preset positions, the screw 7 penetrates through the four sleeves and is locked, so that the height of the first supporting part 31 and the height of the second supporting part 32 are adjusted and locked.
In some embodiments, a side of the second support member 32 facing the first support member 31 is provided with a pressing member 35 for pressing a switch of the work tool 10.
Since the switch of the power tool 10 needs to be continuously pressed during the operation, in order to ensure the continuous operation of the power tool 10, the pressing member 35 is provided on the second support member 32, and the switch of the power tool 10 can be continuously pressed after the power tool 10 is mounted on the tool holder 3, so that the power tool 10 can be continuously operated.
In some embodiments, the push rod 5 is hinged to the second support member 32, and the pressing member 35 includes a connecting portion disposed coaxially with the push rod 5 and connected to the push rod 5 through the second support member 32, and a pressing portion bent with respect to the connecting portion for pressing a switch of the work tool 10.
That is, the connecting portion of the pressing member 35 is coaxially connected to the push rod 5 and is hinged to the second support member 32, and the pressing portion is located at the end of the connecting portion and can move along with the rotation of the push rod 5. When the push rod 5 rotates away from the ground, the pressing part rotates towards the direction close to the workbench 2 and is separated from the switch of the working tool 10; when the push lever 5 is rotated in a direction to approach the ground, the pressing portion is rotated in a direction to move away from the table 2, so that the switch of the power tool 10 is pressed, thereby controlling the operation of the power tool 10.
Specifically, since the length of the propelling rod 5 is relatively large during the propelling process of the work tool 10, the propelling rod 5 may be a telescopic rod structure for easy installation and transportation, or the propelling rod 5 is hinged to the second support member 32 through the mounting seat 6, and the propelling rod 5 is detachable from the mounting seat 6. When the push lever 5 is connected to the mount 6 to effect the hinge connection of the push lever 5 to the second support member 32, the connection portion of the pressing member 35 is connected to the mount 6.
In some embodiments, the clamping assembly 1 includes a frame 11, a pressing plate 12, and an adjusting assembly, where the frame 11 includes a first side plate, the pressing plate 12 is disposed in the frame 11 and opposite to the first side plate, a beam clamping space is formed between the first side plate and the pressing plate 12, and the adjusting assembly is configured to adjust a position of the pressing plate 12 to adjust a size of the beam clamping space.
When clamping assembly 1 and roof beam body lower extreme centre gripping cooperation, at first with framework 11 cladding at roof beam body lower extreme department to with first curb plate and roof beam body butt, then operation adjusting part changes the position of clamp plate 12, make the opposite side butt of clamp plate 12 and roof beam body, thereby realize the centre gripping cooperation of clamping assembly 1 and roof beam body.
In order to increase the friction force between the clamping assembly 1 and the beam, a non-slip pad may be disposed between the clamping assembly 1 and the beam, or a rough surface may be disposed on the surface of the first side plate and the pressing plate 12 to increase the friction force between the clamping assembly 1 and the beam.
Specifically, frame 11 includes the second curb plate, and adjusting part includes threaded rod 13 and adjustment handle 14, and threaded rod 13 and second curb plate screw-thread fit, and one end passes the second curb plate and is connected with clamp plate 12, and the other end is connected with adjustment handle 14.
In this embodiment, the threaded rod 13 of the adjusting assembly is in threaded connection with the second side plate, and the relative position of the threaded rod 13 and the second side plate can be adjusted by rotating the adjusting handle 14, so that the position of the pressing plate 12 is adjusted to ensure that the pressing plate 12 abuts against the beam body. The adjusting assembly is simple in structure and convenient to operate.
It is noted that, in this document, relational terms such as "first" and "second," and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The foregoing are merely exemplary embodiments of the present disclosure, which enable those skilled in the art to understand or practice the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. The utility model provides an improve and face instrument of limit trompil operation security and work efficiency which characterized in that includes: workstation (2), the one end of workstation (2) is provided with centre gripping subassembly (1) that is used for the centre gripping roof beam body, be provided with tool holder (3) that are used for fixed working tool (10) on workstation (2), tool holder (3) with workstation (2) sliding fit, tool holder (3) are kept away from one side of centre gripping subassembly (1) is provided with push rod (5) to ground extension.
2. The tool for improving the safety and the work efficiency of the limb hole opening operation according to claim 1, wherein the clamping assembly (1) comprises a frame body (11), a pressing plate (12) and an adjusting assembly, the frame body (11) comprises a first side plate, the pressing plate (12) is arranged in the frame body (11) and is opposite to the first side plate, a beam body clamping space is formed between the first side plate and the pressing plate (12), and the adjusting assembly is used for adjusting the position of the pressing plate (12) so as to adjust the size of the beam body clamping space.
3. The tool for improving the safety and the ergonomics of the rimming operation of claim 2, wherein the frame body (11) comprises a second side plate, and the adjusting assembly comprises a threaded rod (13) and an adjusting handle (14), the threaded rod (13) is in threaded fit with the second side plate, one end of the threaded rod penetrates through the second side plate to be connected with the pressing plate (12), and the other end of the threaded rod is connected with the adjusting handle (14).
4. A tool for improving the safety and the work efficiency of edge-facing hole opening operation according to claim 1, wherein a slide rail (4) is arranged on the workbench (2), and the tool seat (3) is connected with the slide rail (4) in a sliding manner.
5. A tool for improving safety and ergonomics of a limb-drilling operation according to claim 1, wherein the tool holder (3) comprises a first support member (31) for supporting the front end of the operation tool (10) and a second support member (32) for supporting the rear end of the operation tool (10), the first support member (31) and the second support member (32) being detachably connected.
6. A tool for improving the safety and ergonomics of a limb aperturing operation according to claim 5 wherein the first support member (31) includes a support platform (33) disposed away from one end of the table (2), the support platform (33) extending away from the second support in a direction parallel to the table (2).
7. A tool for improving the safety and efficiency of a limb drilling operation according to claim 6, wherein the support platform (33) is provided with a first opening (34) for mating with a front end handle of the operation tool (10).
8. A tool for improving the safety and ergonomics of a limb-drilling operation according to claim 5, wherein the second support member (32) is provided with a pressing member (35) for pressing the switch of the operation tool (10) on the side facing the first support member (31).
9. A tool for improving the safety and ergonomics of a rimming operation according to claim 8 wherein the push rod (5) is hinged to the second support member (32).
10. A tool for improving safety and ergonomics of a limb-piercing operation according to claim 9 wherein the pressing member (35) comprises a connecting portion disposed coaxially with the push rod (5) and connected to the push rod (5) through the second support member (32), and a pressing portion bent with respect to the connecting portion for pressing the switch of the operation tool (10).
CN202221055659.3U 2022-05-05 2022-05-05 Tool for improving safety and work efficiency of edge-facing hole opening operation Active CN217453826U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202221055659.3U CN217453826U (en) 2022-05-05 2022-05-05 Tool for improving safety and work efficiency of edge-facing hole opening operation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202221055659.3U CN217453826U (en) 2022-05-05 2022-05-05 Tool for improving safety and work efficiency of edge-facing hole opening operation

Publications (1)

Publication Number Publication Date
CN217453826U true CN217453826U (en) 2022-09-20

Family

ID=83273820

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202221055659.3U Active CN217453826U (en) 2022-05-05 2022-05-05 Tool for improving safety and work efficiency of edge-facing hole opening operation

Country Status (1)

Country Link
CN (1) CN217453826U (en)

Similar Documents

Publication Publication Date Title
US5885036A (en) Hand held drill press and method of use
US5791835A (en) Holding fixture used in woodworking for preparing pocket joints
US7226252B2 (en) Hand-held drill leverage unit
US20190001521A1 (en) Wood splitting device and wood splitting method
CN217453826U (en) Tool for improving safety and work efficiency of edge-facing hole opening operation
CN212885906U (en) Metal material welding equipment for oil recovery machine production and assembly
US7631674B2 (en) Working machine having distance adjustment function
US20050152756A1 (en) Universal pressure drill and srew runner
CN215204228U (en) Drawing device for environmental art design
CN213257694U (en) Laser marking machine
CN212469943U (en) Workpiece clamping device for double housing planer
CN210335061U (en) Pincers handle sheath pusher
GB2286144A (en) Portable work bench
CN108453685B (en) Tool box capable of changing bench clamp block into bench saw backer
CN220313117U (en) Aluminum-based honeycomb fixing seat
KR101499529B1 (en) The jig for hole cutting machine and hole cutting method using the same
CN211565172U (en) Multi-angular position parallel clamping tool for machining bench drill or bench saw
CN215432577U (en) Punching workbench for building decoration
CN219133709U (en) Adjustable wood component engraving fixture
CN2391703Y (en) Machine for processing aluminium shaped materials
CN219874841U (en) Special frock of cable head preparation
CN210413242U (en) Quick positioner of welding frock
CN216632852U (en) Pipe surface slotting equipment
CN215357632U (en) Novel side cut polish-grinding equipment
CN216731139U (en) Angle grinder workbench

Legal Events

Date Code Title Description
GR01 Patent grant
GR01 Patent grant