Hand tool head assembly and housing device

Abstract

A handheld tool, such as an electric cordless ratchet wrench, is configured to have a reduced number of parts and a reduced assembly process. The handheld tool includes a clamshell housing that can be secured to a drive member, such as a ratchet head assembly, without requiring additional fasteners, such as a large clamping nut or an additional set of screws. One or more protrusions extending inwardly from the clamshell housing mate with similarly shaped voids in the ratchet head assembly. When the clamshell housing portions are secured together, the protrusions tightly mate with the ratchet head housing.

Description

Technical Field

[0001] The present invention relates to a powered hand tool for applying torque to a workpiece. More particularly, the present invention relates to a clamshell housing connected to a head assembly of a powered hand tool. Background Art

[0002] Powered hand tools, such as electric ratchets and drivers, are commonly used in automotive, industrial, and household applications to install and remove threaded fasteners and to apply torque and / or angular displacement to a workpiece, such as a threaded fastener. Powered hand tools, such as cordless electric ratchets and drivers, typically include a motor that is housed in a clamshell housing along with other components, such as a switch, a light emitting diode (LED), and a battery. The clamshell housing typically includes two or more housing portions that are secured together by fasteners, such as screws or rivets.

[0003] The process of mounting a clamshell housing to a drive member, such as a ratchet head contained in a power hand tool, typically involves, in addition to the fasteners, one or more large retaining nuts or a set of screws for connecting the portions of the clamshell housing together. The additional large retaining nuts and / or screws can create an unsightly appearance and increase the bulk of that portion of the tool, thereby hindering the use of the tool in small spaces. The large retaining nuts can also become loose over time, causing the ratchet head to loosen from the clamshell housing. Summary of the invention

[0004] According to an embodiment of the present invention, an electric hand tool, such as a cordless ratchet wrench, includes a clamshell housing that can be secured to a drive member, such as a ratchet head assembly, without the need for additional fasteners, such as a large clamping nut or an additional screw set. One or more protrusions extending inward from the clamshell housing cooperate with similarly shaped gaps within the ratchet head assembly. The protrusions may include radial flanges, T-shaped protrusions, and / or one or more screw bosses. When the clamshell housing portions are secured together, the protrusions are tightly contained within the ratchet head housing. The rigid connection established between the clamshell housing and the ratchet head housing absorbs torque and helps prevent the tool from falling apart when the tool is dropped or otherwise impacted.

[0005] According to other aspects of the present invention, the cost of the electric hand tool can be reduced by reducing the number of parts and eliminating the operating steps involved in installing the fastening nuts or screws used to secure the ratchet head assembly to the clamshell housing. The hand tool of the present invention is more aesthetically pleasing and has fewer external fasteners that may loosen and / or affect the comfort of use of the tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] In order to facilitate the understanding of the subject matter to be protected, embodiments of the present invention are shown in the accompanying drawings. With reference to the following description, the subject matter to be protected, its structure and operation, and the multiple advantages of the present invention can be understood.

[0007] Figure 1A A side view of an exemplary tool, such as a cordless ratchet tool including a ratchet head assembly coupled to a motor assembly, is shown in accordance with an embodiment of the present invention.

[0008] Figure 1B A top view of an exemplary tool, such as a cordless ratchet tool including a ratchet head assembly coupled to a motor assembly, is shown in accordance with an embodiment of the present invention.

[0009] Figure 2 An exploded view of an example tool of an embodiment of the present invention is shown having a ratchet head, a motor and a clamshell housing assembly of a cordless ratchet tool.

[0010] Figure 3 An exploded view of an example tool of an embodiment of the present invention is shown having a ratchet head, a motor, a switch and a clamshell housing assembly of a cordless ratchet tool.

[0011] Figure 4A An example tool of an embodiment of the present invention is shown having a ratchet head and a motor assembly.

[0012] Figure 4B A ratchet head housing of a cordless ratchet tool according to an embodiment of the present invention is shown.

[0013] Figure 4C A cross-sectional view of a ratchet head housing of a cordless ratchet tool according to an embodiment of the present invention is shown.

[0014] Figure 4D A motor end plate of a cordless ratchet tool according to an embodiment of the present invention is shown.

[0015] Figure 5 A clamshell housing portion of an embodiment of the present invention is shown.

[0016] Figure 6 A flow chart showing a method of assembling a cordless ratchet tool according to an embodiment of the present invention is shown.

[0017] It should be understood that the opinions contained in the comments, as well as the materials, dimensions and tolerances discussed herein are simply suggestions and that variations may be made by those skilled in the art within the scope of the present invention. DETAILED DESCRIPTION

[0018] While the present invention may be embodied in many forms, which embodiments are shown in the drawings and will be described in detail herein, it should be understood that the preferred embodiments of the invention are exemplifications of the principles of the invention and are not intended to limit the scope of the invention.

[0019] Embodiments of the present invention may be implemented as a handheld tool, such as Figure 1A The cordless ratchet tool 100 includes a handle portion 102 connected to a drive portion 104. The drive portion 104 may include a ratchet head assembly 106, which includes a ratchet housing 112, a ratchet head 110, and a selection button 108. The handle portion 102 may include a main housing 114 that houses a motor, a switch assembly, and one or more status indicator lights, such as light emitting diodes (LEDs). Figure 1B A top view of the cordless ratchet tool is shown. Figure 1B The main housing 114 may be comprised of two or more flip-top housing portions 116 , 118 that are fixedly assembled together and reliably connected to the ratchet head assembly 106 .

[0020] Figure 2 The ratchet head assembly 206 of the cordless ratchet tool assembly 200 according to one embodiment of the present invention is shown connected to the motor assembly 220. The first clamshell housing portion 216 and the second clamshell housing portion 218 of the cordless ratchet tool assembly 200 are configured to be installed around the motor assembly 220.

[0021] Figure 3 The ratchet head assembly 306 of the cordless ratchet tool assembly 300 according to another embodiment of the present invention is shown connected to the motor assembly 320 and the switch assembly 322. The first flip cover housing portion 316 and the second flip cover housing portion 318 of the cordless ratchet tool assembly 300 are configured to be installed around the motor assembly 320.

[0022] refer to Figures 4A-4D , describes a ratchet head and motor assembly 400 according to one embodiment of the present invention. Figure 4A The ratchet head and motor assembly 400 shown includes a motor assembly 420 connected to the ratchet head assembly 406. The motor assembly 420 includes a motor 420 that is connected to a motor end plate, such as Figure 4D Engine end plate 424 is shown.

[0023] The engine end plate 426 can be secured to the engine 424 by fasteners, such as rivets or screws, through fastener holes 430. According to one embodiment of the present invention, the engine end plate 426 includes one or more outwardly protruding semi-annular flanges 428. The flanges 428 are configured to fit within a semi-annular groove 432 formed by a bottom notch below a lip 434 that surrounds the periphery of the ratchet head housing 412. One or more notches on the lip 434 create one or more gaps 436, the gap size being designed to fit and accommodate each of the one or more flanges 428 of the engine end plate 426 during the process of installing and removing the engine end plate 426 from the ratchet head housing 412. The engine end plate 426 may also include one or more pawl structures (not shown) that are designed to provide a tactile indication of appropriate rotational displacement during assembly.

[0024] According to an embodiment of the present invention, the engine assembly 420 is connected to the ratchet head housing 412 by pushing the flange 428 of the engine end plate 426 through the gap 436 on the lip 434 of the ratchet head housing 412, and then rotating the engine assembly 420 relative to the ratchet head housing 412 until the flange 428 of the engine end plate 426 is fixed in the semi-annular groove 432 of the ratchet head housing 412. In one embodiment, the flange 428 and the gap 436 are sized so that the engine assembly 420 can be rotated 90 degrees in any direction to mate with the semi-annular groove 432 of the ratchet head housing 412 during installation, or so that the engine assembly 420 can be rotated 90 degrees in any direction to disengage from the semi-annular groove 432 of the ratchet head housing 412 during removal. A compressible member such as a steel wave washer or an O-ring (not shown) made of a compressible material such as rubber or other elastomer may be installed between the motor assembly 420 and the ratchet head housing 412 to eliminate dimensional tolerances. When the motor assembly 420 is installed on the ratchet head housing 412, the compressible member is compressed and provides pressure between the flange 428 and the lip 434, such as to facilitate the sealing fit and alignment of the transmission gear.

[0025] In an embodiment of the present invention, when the clamshell housing is mounted to the ratchet head and motor assembly 400, the ribs protruding inwardly from one or more clamshell housing portions are shaped to substantially fill the one or more gaps 436. Figure 5The one or more semi-annular ribs 536 in the first clamshell housing portion 516 are shaped to substantially fill the one or more gaps 436. The semi-annular ribs 536 prevent the motor end plate 426 from rotating out of the slot 432 in the ratchet head housing 412.

[0026] According to another embodiment of the present invention, one or more of the flip-top housing portions include one or more protrusions extending inwardly from the flip-top housing. The one or more protrusions mate closely with similarly shaped voids in the ratchet head assembly. Figure 5 The protrusion may include a radial flange 538, a T-shaped protrusion 540, and / or one or more screw bosses 542. The protrusion mates closely with the ratchet head housing when the clamshell housing portions are secured together. Figures 4A-4C The ratchet head housing 412 may include a radial flange groove 438, a T-shaped hole 440, and / or one or more concave channels 442, configured to tightly accommodate the radial flange 538, T-shaped protrusion 540, and / or one or more screw bosses 542, respectively.

[0027] refer to Figure 2 , the first flip-top housing portion 216 can be fixed to the second flip-top housing portion 218 around the ratchet head assembly 206 using fasteners such as screws or rivets. Figure 1A and 1B As shown, the inward projection on the flip-top housing prevents the ratchet head assembly from axially rotating or moving relative to the flip-top housing. Figure 1A and 1B The cordless ratchet tool 100 shown may include a radial flange 538, a T-shaped protrusion 540, and / or one or more screw bosses 542 that cooperate with the radial flange groove 438. The T-shaped hole 440 and / or one or more concave channels 442 described above are intended to reduce the number of parts and eliminate the installation step of the fastening nut or screw used to secure the ratchet head assembly to the clamshell housing. The disclosed cordless ratchet tool 100 can be constructed without outwardly protruding fastening nuts or screws that may become loose and / or affect the comfort of use of the tool.

[0028] Figure 6A flow chart of a method 600 for assembling a hand tool according to an embodiment of the present invention is shown. As shown, the method 600 begins and proceeds to step 602, which includes aligning one or more protrusions of a first clamshell housing portion with one or more similarly shaped gaps in a ratchet head assembly. In step 604, the method includes installing the one or more protrusions into the one or more similarly shaped gaps. In step 606, the method includes aligning a second clamshell housing portion with the first clamshell housing portion. In step 608, the method includes installing fasteners to connect the first clamshell housing portion to the second clamshell housing portion. According to an embodiment of the present invention, the one or more protrusions may include radial flanges, T-shaped protrusions, and / or screw bosses extending inwardly from the first clamshell housing portion.

[0029] As described above, the embodiments of the present invention describe a cordless ratchet tool 100 as shown in the accompanying drawings. However, it should be understood that aspects of the present invention may be embodied as other hand-held tools or embodiments. For example, but not limited to, the hand-held tool may be a ratchet wrench, an open-end wrench, a screwdriver, a nut runner, or any tool capable of applying torque to a workpiece.

[0030] As used herein, the term "connected" or "communicably coupled" may refer to any physical, electrical, magnetic or other connection, direct or indirect, between two components. The term "connected" is not limited to a fixed, direct connection between two entities.

[0031] The subject matter listed in the above description and drawings is for illustrative purposes only and is not intended to limit the present invention. Although specific embodiments are shown and described, it is apparent to those skilled in the art that changes and modifications may be made without departing from the scope of the present invention. The scope of the present invention is defined by the following claims.

Claims

1. An electric handheld tool, comprising: a head assembly operably connected to an engine assembly, wherein the head assembly includes a semi-annular groove formed by a notch of a lip disposed around the periphery of the head assembly, the semi-annular groove being adapted to cooperatively receive an outwardly protruding semi-annular flange of the engine assembly to connect the engine assembly to the head assembly, wherein the head assembly includes a head housing having a shaped hole and a concave channel formed on an outer periphery of the head housing, wherein the concave channel extends in a direction perpendicular to a longitudinal axis of the head housing; and A flip-top housing, which includes a first and a second flip-top housing part, and the first and second flip-top housing parts are suitable for being arranged around the engine assembly to cooperatively define a flip-top cavity, which accommodates at least a portion of the head assembly, and the portion of the head assembly includes the shaped hole and the concave channel, the first flip-top housing part includes an inwardly protruding protrusion located on its inner wall and an inwardly extending screw boss, wherein the inwardly protruding protrusion cooperatively engages and fills the shaped hole, and the screw boss cooperatively engages the concave channel, and the engagement of the inwardly protruding protrusion with the shaped hole, and the engagement of the screw boss with the concave channel hinder the rotation and axial movement of the head housing relative to the flip-top housing.

2. The electric hand tool according to claim 1, characterized in that: The shaping hole and the inwardly protruding protrusion are both T-shaped.

3. The electric hand tool according to claim 1, characterized in that: Further included is a compressible member disposed between the engine assembly and the head housing.

4. The electric hand tool according to claim 1, characterized in that: Also included is a fastener received within the screw boss to couple the first clamshell housing portion to the second clamshell housing portion to cooperatively define the clamshell cavity.

5. The electric hand tool according to claim 1, characterized in that: The head housing includes a radial flange groove arranged on the outer periphery thereof, and the flip-top housing includes a radial flange cooperatively engaged with the radial flange groove to prevent the head housing from axially moving relative to the flip-top housing.

6. The electric hand tool according to claim 1, characterized in that: The concave channel includes a first concave channel and the head assembly includes a second concave channel circumferentially spaced from the first concave channel.

7. The electric hand tool according to any one of claims 1 to 6, characterized in that: The electric handheld tool is an electric cordless ratchet wrench, wherein the head assembly is a ratchet head assembly and the head housing is a ratchet head housing.

8. A method for assembling an electric hand tool, comprising: connecting the head assembly to the engine assembly by placing an outwardly projecting semi-annular flange of the engine assembly into a mating semi-annular groove formed by a notch in a lip disposed around the periphery of the head assembly; aligning an inwardly protruding screw boss disposed on an inner wall of the first clamshell housing portion with a concave channel formed on an outer periphery of the head housing of the head assembly; aligning an inwardly protruding protrusion provided on an inner wall of the first clamshell housing portion with a shaped hole formed on an outer periphery of a head housing of the head assembly; inserting the screw boss into the concave channel, wherein the concave channel extends in a direction perpendicular to the longitudinal axis of the head housing, and wherein the screw boss is cooperatively engaged with the concave channel; inserting the inwardly protruding protrusion into the shaped hole, wherein the inwardly protruding protrusion cooperatively engages with the shaped hole; aligning a second clamshell housing portion with the first clamshell housing portion such that at least a portion of the head housing is received within a cavity formed by the first and second clamshell housing portions; and The first and second clamshell housing portions are connected together by fasteners disposed within the screw bosses to cooperatively define the cavity.

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