This description relates to a tool attachment for raking mortar joints. Raking mortar joints is a typical step in repointing structures and can be useful for increasing the lifetime and structural integrity of brick buildings, stone walls, and other masonry constructed structures.
In masonry, structures are generally built from individual units held together by hardened mortar. For example, a brick building is a masonry constructed structure in which the bricks (the individual units) are held together by a mixture of water, sand, and cement (the mortar). The space between the individual units that is filled or intended to be filled with mortar is called a mortar joint. With the passage of time, mortar can deteriorate, weaken, become damaged, etc.
The apparatus, systems, and techniques described herein can aid individuals such as masons, construction workers, homeowners etc. with joint raking. An attachment for a power tool, such as a powered rotary hammer drill, may increase control of the power tool by stabilizing and guiding the tool during a joint raking operation. By providing users better control of the power tool, the attachment enables users to remove mortar with reduced fatigue, fine dust particles, and damage to individual units of a masonry constructed structure compared to conventional apparatuses, systems, and techniques for repointing.
In one aspect, an apparatus configured to be mounted to a power tool includes a hollow shaft configured to surround an operating element of the power tool; a substantially flat sled, in which a bottom surface of the sled is configured to interface with a working surface; and a guidance fin protruding from the bottom surface of the sled, wherein the guidance fin is configured to guide the apparatus along an operating path.
Implementations may include one or more of the following features. The guidance fin may protrude substantially perpendicularly from the bottom surface of the sled, may be configured to fit into a mortar joint, and/or may have a width that is less than a width of the operating element of the power tool. The power tool can be a rotary hammer drill. The hollow shaft can be oriented at an acute or an obtuse angle relative to the sled. At least one edge of the substantially flat sled may be configured to curve away from the working surface. The apparatus can be configured to rotate relative to the power tool about a longitudinal axis of the hollow shaft. A dimension of at least one of the hollow shaft, the sled, and the guidance fin can be adjustable. A front aspect of a distal end of the hollow shaft may have a cutout. A front aspect of the sled may be bifurcated. The apparatus may include at least one vacuum port attachment, which can be mounted to a top surface of the sled and/or may be built into a support member of the apparatus. The apparatus may include a clamp configured to mount the apparatus to the power tool. The clamp, which can be a split collar clamp, may be configured to interface with a chuck of the power tool and may have a cam-operated tightening mechanism. The apparatus can be configured to rotate relative to the power tool about a longitudinal axis of the hollow shaft only when the clamp is in an unlocked configuration. The clamp can include at least one locator feature for locating at least one predetermined position of the apparatus, and the least one locator feature may be a ball detent.
In another aspect, a system includes a power tool with an operating element; a hollow shaft configured to surround the operating element; a substantially flat sled, wherein a bottom surface of the sled is configured to interface with a working surface; and a guidance fin protruding perpendicularly from the bottom surface of the sled, wherein the guidance fin is configured to guide the apparatus along an operating path.
Implementations may include one or more of the following features. The hollow shaft and/or the sled may be irremovable from the power tool. The guidance fin may protrude substantially perpendicularly from the bottom surface of the sled, may be configured to fit into a mortar joint, and/or may have a width that is less than a width of the operating element of the power tool. The power tool can be a rotary hammer drill. The hollow shaft can be oriented at an acute or an obtuse angle relative to the sled. At least one edge of the substantially flat sled may be configured to curve away from the working surface. The sled can be configured to rotate relative to the power tool about a longitudinal axis of the hollow shaft. A dimension of at least one of the hollow shaft, the sled, and the guidance fin can be adjustable. A front aspect of a distal end of the hollow shaft may have a cutout. A front aspect of the sled may be bifurcated. The system may include at least one vacuum port attachment, which can be mounted to a top surface of the sled and/or may be built into a support member of the system.
In another aspect, an apparatus that is configured to be rotatably mounted to a power tool includes a hollow shaft, a substantially flat sled, a guidance fin, at least one vacuum port attachment, and a split collar clamp. The hollow shaft is configured to surround an operating element of the power tool, and a front aspect of a distal end of the hollow shaft has a cutout. The sled is oriented at an acute angle relative to the hollow shaft. A front aspect of the sled is bifurcated and a bottom surface of the sled is configured to interface with a working surface. The guidance fin protrudes substantially perpendicularly from the bottom surface of the sled and has a width that is less than a width of the operating element of the power tool. The guidance fin is configured to fit inside a mortar joint and guide the apparatus along an operating path. The at least one vacuum port attachment is built into a support member of the apparatus. The split collar clamp is configured to interface with a chuck of the power tool. The clamp has a cam-operated tightening mechanism and at least one locator feature for locating at least one predetermined position of the apparatus. The apparatus is configured to rotate relative to the power tool about a longitudinal axis of the hollow shaft.
These and other aspects, features, and various combinations may be expressed as apparatuses, systems, methods, means for performing functions, etc.
Other features and advantages will be apparent from the description and the claims.
In masonry, mortar is used for the spacing of individual units, adhering the individual units, and maintaining the structural integrity of the masonry constructed structure. Over time, the mortar in a masonry constructed structure can deteriorate at a rate dependent on factors including pollution, moisture, material selection, and workmanship quality. In some cases, to increase the lifetime and structural integrity of masonry constructed structures, damaged mortar is removed from mortar joints and replaced with fresh mortar through a process called repointing. The removal of the mortar from the mortar joints is commonly referred to as joint raking.
Conventional tools used for joint raking include hand tools powered solely by manual labor such as masonry mash hammers and chisels. The use of these hand tools may be tiring, may limit the rate at which joint raking can be completed, and may generate unsafe or undesired quantities of fine dust as the mortar is removed. The use of power tools such as power saws and grinders can reduce user fatigue and increase the rate of mortar removal compared to the use of hand tools powered solely by manual labor. However, conventional power tools used for joint raking may cause damage to the individual units due to lack of control, may provide cuts of non-uniform depth, and may generate large quantities of unsafe or undesired fine dust as the mortar is removed. Consequently, there is a need for tools and tool attachments that enable rapid and well-controlled joint raking with minimal damage to the individual units and reduced generation of fine dust particles.
Here, we describe, among other things, a tool attachment that can be used in combination with power tools (e.g. a rotary hammer drill) to assist users in performing tasks such as joint raking. Users may include, but are not limited to, masons, construction workers, homeowners, and any other persons responsible for maintaining a masonry constructed structure.
We use the term “power tool” broadly to include, for example, any combination of hardware or software components or both that is used to carry out a particular function and has a power source other than pure manual labor. Examples of power tools include, but are not limited to, rotary hammer drills, hammer drills, electric grinders, power saws, and power sanders.
We use the term “joint raking” broadly to include, for example, any removal of mortar or other material from a mortar joint. In some cases, mortar may be removed from the mortar joint because it has been damaged or deteriorated due to factors such as pollution, moisture, material selection, and workmanship quality.
We use the term “mortar joint” broadly to include, for example, any space between individual units in a constructed structure such as a masonry constructed structure. In some cases, the individual units may comprise bricks, stones, concrete blocks, cast stone, glass block, adobe, or any combination of them. In some cases, the mortar may comprise a mixture of water, sand, polymers, lime, pozzolana, or any combination of them, among other things.
The joint raking tool attachment 102 comprises a hollow shaft 112 that substantially surrounds the operating bit 120 of the rotary hammer drill 104 and is mounted, at a proximal end, to the rotary hammer drill 104 via a split collar clamp 114 (e.g., mounted to a chuck of the rotary hammer). At a front aspect of a distal end of the hollow shaft 112 a cutout 118 partially exposes a tip of the operating bit 120 of the rotary hammer drill 104. The joint raking tool attachment 102 further includes a sled 116 that, during a joint raking operation, interfaces with the working surface. The joint raking tool attachment 102 and the split collar clamp 114 are later described in relation to
While a rotary hammer drill is depicted in
Referring to
When the joint raking tool attachment 102 is mounted to the rotary hammer drill 104, the hollow shaft 112 is configured to extend longitudinally along the axis of the operating bit 120 and substantially surround the operating bit 120. At the distal end of the hollow shaft, the cutout 118 is configured to expose a distal tip of the operating bit 120, enabling the operating bit 120 to interface with a working surface such as a brick wall. The hollow shaft 112 provides protection to the user, for example, by limiting unintentional user contact with the operating bit 120. In addition, the hollow shaft 112 partially defines an operating depth (e.g. a cutting depth) of the operating bit 120 by limiting the exposed length of the operating bit 120.
The joint raking tool attachment 102 further includes a sled 116, attached to the hollow shaft 112, and configured to interface with the working surface. During a joint raking operation, a substantially flat bottom surface of the sled 116 is configured to lay flush against the working surface, partially defining the operating depth of the operating bit 120. While the bottom surface of the sled 116 is substantially flat, in some cases, the edges of the sled 116 may be configured to curve away from the working surface to smoothly guide the joint raking system 100 along the working surface and reduce wear of the sled 116. In some cases, the bottom surface of the sled 116 may be textured (e.g. with patterns or designs carved in) to provide better traction with the working surface and prevent debris from getting trapped underneath the sled 116. In some cases, a front aspect of the sled 116 may be bifurcated (e.g. into bifurcated halves 204A, 204B) to expose an operating path of the operating bit 120. This exposure may provide visual feedback to a user to assist in guiding the joint raking system 100 and may prevent debris from getting trapped underneath the sled 116.
In some cases, the sled 116 forms an acute angle with the hollow shaft 112. The acute angle may contribute to reduced user fatigue, since as the user pushes the joint raking system 100 against the working surface, a component force substantially parallel to the working surface assists in guiding the joint raking system 100 along an intended operating path. In some cases, a support member 202 may be included between the sled 116 and the hollow shaft 112 so that their relative positions do not substantially change when a user pushes the joint raking system 100 against the working surface. While the sled 116 and the hollow shaft 112 form an acute angle in
As previously described, the operating depth (e.g. the cutting depth) of the operating bit is partially defined by the hollow shaft 112 and the sled 116. For joint raking implementations, a desired operating depth may be approximately 2.5 times a width of the mortar joint. In some cases, the operating depth of a joint raking system (e.g. joint raking system 100) can be adjusted by replacing the joint raking tool attachment 102 with another joint raking tool attachment having a hollow shaft of a different length. In some cases, the hollow shaft 112 of the joint raking tool attachment 102 may have an adjustable length, enabling a single joint raking tool attachment 102 to allow for various operating depths. In some cases, the operating depth can be adjusted by repositioning the sled 116 at different points along the length of the hollow shaft 112.
Referring to
In some implementations, dimensions of the hollow shaft 112, the sled 116, the guidance fin 206, or any combination of them may be adjustable. For example, in some cases, the hollow shaft 112 can telescope to a different length. In some cases, the sled 116 can be lengthened or shortened to adjust an area that interfaces with the working surface. In some cases, the guidance fin 206 may have an adjustable length, or depth, or both.
The sled 116, the guidance fin 206, or both can be made of metals such as steel so that they are durable against wear. In some cases, the sled 116, the guidance fin 206, or both can be made of plastic, a combination of materials, etc. and may be replaced (e.g., to address wear and tear, to interface with different types of work surfaces, etc.) In some cases, the sled 116, the guidance fin 206, or both can be coated with wear-resistant materials such as chromes, carbides, ceramics, epoxies, teflons, diamond, etc.
Referring to
Referring to
In this implementation, the split collar clamp 114 is a dual clamp that attaches the joint raking tool attachment 102 to the rotary hammer drill 104. A power tool half 402 of the split collar clamp 114 mounts to the rotary hammer drill 104 (e.g. to the chuck of the rotary hammer drill) with a threaded fastener threading across a split axis 406 to tighten the clamp. A tool attachment half 404 of the split collar clamp 114 mounts to the proximal end of the hollow shaft 112 of the joint raking tool attachment 102 with a threaded fastener threading across the split axis 406 to tighten the clamp. The tool attachment half 404 of the split collar clamp 114 further tightens via the use of a cam handle 408. In some cases, the cam handle 408 can be considered a cam-operated tightening mechanism.
Referring to
Referring to
While a tool attachment is described, in some cases, a dedicated power tool may also be used, comprising similar features to the tool attachment, but in an irremovable configuration. For example, the hollow shaft 112 may be permanently fixed to the operating element of the power tool or could be a continuous piece of material. In such an embodiment, a connecting feature such as the split collar clamp 114 would not be required.
A number of embodiments have been described. Nevertheless, it will be understood that various modifications can be made without departing from the spirit and scope of the apparatus, systems, and techniques described herein. In addition, other components can be added to, or removed from, the described apparatus and systems. Accordingly, other embodiments are within the scope of the following claims.
This application is a continuation of U.S. patent application Ser. No. 16/108,954, filed on Aug. 22, 2018, which claims the benefit of priority under 35 U.S.C. Section 119(e) to U.S. Provisional Patent Application No. 62/708,336, filed on Dec. 4, 2017, the entire contents of which are incorporated herewith by reference.
Number | Date | Country | |
---|---|---|---|
62708336 | Dec 2017 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 16108954 | Aug 2018 | US |
Child | 16773491 | US |