Patent Application
20210283802
The present disclosure relates to tool adapters and retention systems used to attach tools such as cutting bits to rotary tools such as cutting drums used in milling machines, e.g. a cold planer, and the like. Specifically, the present disclosure relates to a hammerless cutting bit retention system, which may ease disassembly of the cutting bit from the cutting drum, or ease assembly of the cutting bit to the cutting drum.
Rotary tools such as cutting drums are routinely employed by milling machines such as cold planers and the like for ripping up a work surface such as soil, loose rock, asphalt, pavement, concrete, etc. As can be imagined, these rotary tools may use cutting bits adapted to perform the necessary work. These cutting bits are subject to wear. Therefore, it is often necessary to replace these cutting bits once worn. Alternatively, it may be desirable to change out one type of cutting bit for another type of cutting bit depending on the work material. For example, one cutting bit may be well adapted for ripping up concrete while another may be better suited for ripping up asphalt.
For these reasons, tool adapters (also referred to as tool holders) have been developed so that cutting bits may be changed without needing to replace the entire cutting drum. Often, the cutting bits are pressed in the tool holders, then retained with a press fit and/or a threaded fastener. Once the parts are worn out, they need to be replaced by hammering them out, or using a pneumatic or hydraulic tool.
For example, U.S. Pat. No. 5,067,775 discloses a retainer for rotatably retaining a mining tool or a wear resistant sleeve in a support block. It includes a removable collar consisting of at least two semi-annular members each having a flange extending from its inside diameter and a groove disposed about its outside diameter. The removable collar is circumferentially mountable about a rearward portion of either the mining tool or the wear resistant sleeve extending from the support block when mounted therein. The extending rearward portion has a groove circumferentially disposed therein. When the semi-annular members are mated thereabout, the flange of each member cooperates with the groove in the rearward portion of either the mining tool or the wear resistant sleeve. The groove about each semi-annular member defines in combination a substantially continuous groove about the collar. A snap ring is removably mounted in the substantially continuous groove about the removable collar.
However this known retention system as well as other known retention systems may not be as robust and easily assembled/disassembled as desired. Therefore, further improvement in these retention systems are needed.
A retention system according to an embodiment of the present disclosure may comprise a base and a tool adapter. The base may include a retention portion that defines a first locking mechanism receiving cavity, a tool adapter receiving cavity, and a first retention nub receiving groove that is in communication with the first locking mechanism receiving cavity, and the tool adapter receiving cavity. The base may also include a mounting portion comprising a bottom attachment surface that is spaced away from the first locking mechanism receiving cavity and the tool adapter receiving cavity. The tool adapter may include a surface of revolution, and a first retention nub extending from the surface of revolution that is configured to slide within the first retention nub receiving groove of the base.
A cutting bit according to an embodiment of the present disclosure may include a rear adapter portion having a body of revolution, an outer circumferential surface, and a first retention nub extending from the outer circumferential surface. The cutting bit may also include a forward portion, and an intermediate collar portion that is disposed between the rear adapter portion, and the forward portion.
A base according to an embodiment of the present disclosure may comprise a retention portion that defines a first locking mechanism receiving cavity, an adapter portion receiving cavity, and a first retention nub receiving groove that is in communication with the first locking mechanism receiving cavity, and the adapter portion receiving cavity. So, the retention portion may be hollow. The base may also include a mounting portion comprising a bottom attachment surface that is spaced away from the first locking mechanism receiving cavity and the adapter portion receiving cavity. The mounting portion may be solid.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments of the disclosure and together with the description, serve to explain the principles of the disclosure. In the drawings:
Reference will now be made in detail to embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. In some cases, a reference number will be indicated in this specification and the drawings will show the reference number followed by a letter for example, 100a, 100b or by a prime for example, 100′, 100″ etc. It is to be understood that the use of letters or primes immediately after a reference number indicates that these features are similarly shaped and have similar function as is often the case when geometry is mirrored about a plane of symmetry. For ease of explanation in this specification, letters and primes will often not be included herein but may be shown in the drawings to indicate duplications of features, having similar or identical function or geometry, discussed within this written specification.
Various embodiments of an apparatus and a method will be described herein regarding a cutting tool assembly (may also be referred to as a retention system), a base or holder, and a cutting tool for attachment to a rotary cutting drum assembly or the like.
In some embodiments, the retention system may allow for easier replacement of cutting tools without needing a hammer. In some embodiments, a ¾ ratchet may be employed.
Power source 102 may drive the undercarriage assembly(s) 104 of machine 100 at a range of output speeds and torques. Power source 102 may be an engine such as, for example, a diesel engine, a gasoline engine, a gaseous fuel-powered engine, or any other suitable engine. Power source 102 may also be a non-combustion source of power such as, for example, a fuel cell, a power storage device, or any other source of power known in the art.
Undercarriage assembly(s) 104 may include crawler tracks 106. The undercarriage assemblies 104 may be attached to the machine 100 via hydraulic cylinders 108 that may be raised or lowered or rotated to position the machine 100 both vertically or horizontally at a desired position relative to a work surface. Other types of undercarriages may be employed such as those employing wheels, walking mechanisms, etc.
An implement assembly 110, which includes a rotary cutting drum assembly 112 (best seen in
As shown in
A cab 120 is also shown that houses a seat 122 and controls 124 for the operator to use to control the various functions of the machine 100. The configuration of this machine as well as the implement assembly 110 may be varied as needed or desired. The machine of
Looking now at
Starting with
The cutting tool assembly 200 may comprise a base 202 that includes a retention portion 210 (so called since this portion retains a cutting bit and/or tool adapter, etc.) that defines a first locking mechanism receiving cavity 212, a tool adapter receiving cavity 214, and a first retention nub receiving groove 216 that is in communication with the first locking mechanism receiving cavity 212, and the tool adapter receiving cavity 214.
The base 202 may also include a mounting portion 218 (so called since this portion is used to mount the base to the hub, etc.) that comprises a bottom attachment surface 219 that is spaced away from the first locking mechanism receiving cavity 212 and the tool adapter receiving cavity 214 (or the retention portion 210 as a whole).
As best seen in
Referring now to
In
Looking now at
In
Focusing on
Moreover, the retention portion 210 of the base 202 may further comprise a first annular ear portion 234 that defines a first orthogonal longitudinal axis 236 that perpendicularly intersects the first longitudinal axis of the first annular portion 232. This first annular ear portion 234 may also define the first locking mechanism receiving cavity 212 mentioned previously herein.
Likewise, the retention portion 210 of the base 202 may further comprise a second annular ear portion 234′ that defines a second orthogonal longitudinal axis 236′ that is collinear with the first orthogonal longitudinal axis 236. The second annular ear portion 234′ may define a second locking mechanism receiving cavity 212′, and a second retention nub receiving groove 216′ that is in communication with the second locking mechanism receiving cavity 212′, and the tool adapter receiving cavity 214.
These various features may be identical when rotated 180 degrees about the first longitudinal axis 232 but not necessarily so. In some embodiments, the retention portion 210, and the mounting portion 218 of the base 202 may form a “T” shape or a “t” shape with respect to each other when viewed along the first longitudinal axis 232 due to the ear portions.
Furthermore,
Either of the retainer sleeves may be made from a resilient material such as polyurethane and includes a partially annular configuration (e.g. extending circumferentially approximately 180 degrees) including an outer peripheral surface 238 with at least one detent rib 240 extending from the outer peripheral surface 238. Also, either lock retainer may be made from a rigid material such as steel, iron, grey-cast iron, cast iron, etc. and may include a tool engaging portion 242 (may have a socket for receiving a tool) including a stop portion 244 (may also be referred to as a tab), and a locking portion 244 including a nub receiving slot 246 and a catch surface 248. The lock retainer may also have detent groove(s) for mating with the detent rib of the retaining sleeve to hold the lock retainer in a locked or unlocked condition. The first locking mechanism receiving cavity 212 may be delimited by a first abutment surface 250, and a second abutment surface 252 that are spaced 180 degrees from each other about the first orthogonal longitudinal axis 236.
In the assembled condition in
A cutting bit 300 that may be provided as a replacement part according to an embodiment of the present disclosure will now be discussed starting with reference to
The cutting bit 300 may comprise a rear adapter portion 302 including a body of revolution 304 (i.e. a body formed by rotating geometry about an axis, e.g. a cylindrical body, a conical body, etc.) with an outer circumferential surface 306, and a first retention nub 224 that extends from the outer circumferential surface 306. Also, the cutting bit 300 may a forward working portion 308 (so called since this portion has a working edge or working feature such as a point that performs work on a work material, etc.), and an intermediate collar portion 310 that is disposed between the rear adapter portion 302, and the forward working portion 308.
In some embodiments, the outer circumferential surface 306 is a cylindrical surface (e.g. see
As alluded to herein, the forward working portion, the intermediate collar portion, and the rear adapter portion may be joined together as a unitary piece of material (see
In
In addition, the rear adapter portion 302 may further a second retention nub 224′ (see
Next, a base 202 according to an embodiment of the present disclosure that may be provided as a replacement part will now be discussed starting with
The base 202 may comprise a retention portion 210 that defines a first locking mechanism receiving cavity 212, an adapter portion receiving cavity 214′, and a first retention nub receiving groove 216 that is in communication with the first locking mechanism receiving cavity 212, and the adapter portion receiving cavity 214′. Hence, the retention portion 210 may be characterized as being hollow due to the presence of these voids.
On the other hand, the mounting portion 218 comprising a bottom attachment surface 219 (may be arcuate to match the drum) that is spaced away from the first locking mechanism receiving cavity 212, and the adapter portion receiving cavity 214′. Hence, the mounting portion 218 may be characterized as being solid to provide strength and rigidity.
In some embodiments, the adapter portion receiving cavity 214′ extends completely through the retention portion 210. This may not be the case for other embodiments of the present disclosure.
Also, the retention portion 210 may define a second retention nub receiving groove 216′ that is aligned with the first retention nub receiving groove 216 and is also in communication with the adapter portion receiving cavity 214′, forming a “Φ” shape (on its side) with the first retention nub receiving groove 216 and the adapter portion receiving cavity 214′ when viewed along the first longitudinal axis 232.
The first and the second retention nub receiving grooves 214, 214′ may be identically configured being bounded by a side surface 258, and a pair of angled surfaces 260 that form obtuse angles with the side surface 258. Thus, these grooves may be similarly shaped to a retention nub that includes a conical surface 262 and end face 264. Similarly, the adapter portion receiving cavity 214′ may be bounded by an upper cylindrical surface 266, and a lower cylindrical surface 268. So, these surfaces may match the cylindrical profile of the outer circumferential surface 306 of the rear adapter portion 302.
As also alluded to earlier herein, the retention portion 210 may include a first ear portion (e.g. 234) defining the first locking mechanism receiving cavity 212, and a second ear portion (e.g. 234′) defining a second locking mechanism receiving cavity 212′. The first and the second ear portions may be configured such that the retention portion 210 forms a “T” shape or “t” shape with the mounting portion 218 when viewed along the first longitudinal axis 232.
It should be noted that the particulars of the cutting bit, adapter, and base as well as their construction, configuration, method of assembly, etc. are provided by way of an example only and it is contemplated that other embodiments of the present disclosure are possible.
The arrangement, function, and dimensions of the various features of any embodiment of a cutting bit, adapter, and base as discussed herein may be altered as needed or desired to be different than what has been specifically mentioned herein.
In practice, a tool adapter, a cutting tool assembly, a rotary cutting tool assembly, an implement assembly, a cutting bit, a locking mechanism, a base, or a machine using any of these components according to any embodiment described herein may be sold, bought, manufactured or otherwise obtained in an OEM (original equipment manufacturer) or after-market context.
Any portion of the tool adapter, cutting bit, and base may be manufactured from a rigid material such as steel, iron, grey-cast iron, cast iron, etc.
The retention system may be assembled and used as follows for attaching a cutting bit or adapter to a base. First, the base is attached to the drum as previously described herein (e.g. welded). Second, the locking mechanism(s) are assembled into the base by first compressing the resilient retaining sleeve (see arrow 404 in
Fourth, the lock retainer is rotated into an unlocked configuration if it isn't already (see arrow 402 in
If a tool bit wears down or it becomes desirable to change the tool bit for any reason, the user may rotate the lock retainer with a tool such as a ratchet as previously described herein into the unlocked configuration. Then, the tool bit may be removed with a tool such as a pry bar as previously described herein. This may provide for an easier and more robust method of assembly and disassembly than previous known methods and retention systems.
It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the apparatus and methods of assembly as discussed herein without departing from the scope or spirit of the invention(s). Other embodiments of this disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the various embodiments disclosed herein. For example, some of the equipment may be constructed and function differently than what has been described herein and certain steps of any method may be omitted, performed in an order that is different than what has been specifically mentioned or in some cases performed simultaneously or in sub-steps. Furthermore, variations or modifications to certain aspects or features of various embodiments may be made to create further embodiments and features and aspects of various embodiments may be added to or substituted for other features or aspects of other embodiments in order to provide still further embodiments.
Accordingly, it is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention(s) being indicated by the following claims and their equivalents.
