POWER TOOL WITH TRAYS

Abstract

A power tool can include a housing. A power tool can include an electric motor. A power tool can include a printed circuit board assembly configured to supply electrical current to the electric motor. A power tool can include an output unit functionally coupled to the electric motor. A power tool can include a tool terminal block held by the housing and comprising a tool terminal configured to be electrically coupled to the battery. A power tool can include a busbar extending between the tool terminal and the printed circuit board assembly, electrically connecting them, with a section of the busbar defining the tool terminal.

Description

Cross-reference to related registrations

[0001] The present application claims priority over preliminary US patent application No. 63 / 728,374, filed on December 5, 2024, the entire contents of which are incorporated herein by reference. Area

[0002] The present disclosure relates to power tools, in particular a portable, battery-operated power tool. background

[0003] Power tools, especially those operating at high power levels, rely on efficient electrical connections to ensure optimal performance. Conventional connections, such as B+ and B- wires and phase leads to the electric motor, typically consist of conductive metal wires of varying gauges, usually encased in insulation. These wires have limitations regarding contact resistance at the solder joints, heat dissipation due to the wire insulation, and the complexity of installation due to the soldering required during assembly. Overview

[0004] In some aspects, the techniques described here relate to a power tool configured to be selectively and detachably coupled to a battery, the power tool comprising: a housing; an electric motor; a printed circuit board assembly configured to supply electrical current to the electric motor; an output unit functionally coupled to the electric motor; a tool terminal block held by the housing, comprising a tool terminal configured to be electrically connected to the battery; and a busbar extending between the tool terminal and the printed circuit board assembly, electrically connecting them; wherein at least one section of the busbar defines the tool terminal.

[0005] In some aspects, the techniques described here refer to a power tool in which the housing comprises a resin material and in which the busbar is at least partially embedded in the resin material.

[0006] In some aspects, the techniques described here refer to a power tool where the busbar is injection molded with the housing.

[0007] In some aspects, the techniques described here refer to a power tool where the busbar is rigid and comprises a multitude of straight segments connected by a multitude of nonlinear sections.

[0008] In some aspects, the techniques described here refer to a power tool where the multitude of straight segments includes a first segment, a second segment, a third segment, and a fourth segment that are not aligned parallel to each other and are connected at the non-linear sections.

[0009] In some aspects, the techniques described here relate to a power tool in which the busbar comprises a first end and a second end, with the tool connection located at the first end and the second end defining an opening configured to accommodate a screw that secures the second end to the printed circuit board assembly.

[0010] In some aspects, the techniques described here refer to a power tool in which the busbar is a first busbar and the tool terminal is a first tool terminal, with the power tool also comprising a second tool terminal and a second busbar extending between the second tool terminal and the printed circuit board assembly, electrically connecting them.

[0011] In some aspects, the techniques described here relate to a power tool in which the busbar comprises a single monolithic conductive element formed from a conductive metal selected from copper, zinc, aluminum, or an alloy thereof.

[0012] In some aspects, the techniques described here relate to a power tool in which at least one section of the busbar inside the housing is exposed to an airflow generated by a fan of the power tool in order to dissipate heat.

[0013] In some aspects, the techniques described here refer to a power tool in which the exposed section of the busbar is thermally coupled to a heat sink located inside the housing.

[0014] In some aspects, the techniques described here refer to a power tool in which the busbar comprises a first end and a second end, with the tool connection located at the first end and the second end being electrically attached to the printed circuit board assembly by a soldered connection.

[0015] In some aspects, the techniques described here refer to a power tool, whereby the power tool also includes a multitude of phase busbars that electrically connect the printed circuit board assembly to the respective phase windings of the electric motor.

[0016] In some aspects, the techniques described here refer to a power tool in which one end of each phase busbar is secured to a stator insulator of the electric motor.

[0017] In some aspects, the techniques described here relate to a power tool in which each phase busbar comprises a single monolithic conductive element formed from a conductive metal and coupled to the housing by injection molding.

[0018] In some aspects, the techniques described here refer to a power tool where the tool connection is a plug connection designed to be received by a corresponding socket connection of the battery.

[0019] In some aspects, the techniques described here relate to a busbar for a portable, battery-powered power tool, wherein the busbar comprises: a single monolithic conductive element with: a first end defining a tool terminal configured to mate with a battery terminal, a second end configured to be electrically attached to a printed circuit board assembly, and a plurality of straight segments connected by nonlinear sections between the first end and the second end; wherein the busbar is rigid and constructed of a conductive metal.

[0020] In some aspects, the techniques described here relate to a busbar where the second end defines a mounting opening designed to accommodate a threaded fastener to couple the busbar to the printed circuit board assembly.

[0021] In some aspects, the techniques described here relate to a busbar, the busbar being designed so that it can be injection molded into a housing of the portable, battery-operated power tool.

[0022] In some aspects, the techniques described herein relate to a method for assembling a portable, battery-powered power tool, wherein the method comprises: injection molding a busbar into a housing of the portable, battery-powered power tool, the busbar comprising a first end and a second end; and electrically attaching the second end of the busbar to a printed circuit board assembly of the portable, battery-powered power tool; wherein the first end of the busbar defines a tool terminal configured to mate with a battery terminal of a battery.

[0023] In some aspects, the techniques described here refer to a process that also includes inserting a screw through an opening in the second end of the busbar and attaching the second end to the printed circuit board assembly by means of the screw, wherein the busbar is rigid and made of copper, zinc, aluminum or an alloy thereof. Brief description of the drawings Fig. Figure 1 is a side view of a prior art power tool in which a section of the housing has been removed. Fig. Figure 2 is a partial perspective view of a connection block of the power tool according to the state of the art. Fig. 1. Fig. Figure 3 is a perspective view of a battery. Fig. Figure 4 is a side view of a power tool according to an embodiment of the present disclosure, wherein a section of a housing has been removed. Fig. Figure 5 is a partial perspective view of a terminal block of the power tool. Fig. 4. Fig. Figure 6 is a perspective view of the busbars of the power tool. Fig. 4. Fig. 7A is a partial perspective view of the busbar from Fig. 6, which are attached to a printed circuit board assembly (PCBA) of the power tool made of Fig. 4 is attached. Fig. 7B is a partial perspective view of the busbar from Fig. 6, which are attached to a printed circuit board assembly (PCBA) of the power tool made of Fig. 4 is attached, according to a further embodiment of the disclosure. Fig. Figure 8 is a partial side view of a housing of the power tool made of Fig. 4 and the busbar Fig. 6. Fig. Figure 9 is a schematic view showing sections of the power tool. Fig. 4 includes a variety of phase busbars. Detailed description

[0024] Before individual embodiments of the disclosure are explained in detail, it should be noted that the application of the disclosure is not limited to the design details and component arrangements set forth in the following description or illustrated in the following drawings. The disclosure may also include other independent embodiments and may be practiced or implemented in various ways.

[0025] The use of the terms "including" and "comprehensive" and their variations in this description shall encompass the elements listed thereafter and their equivalents, as well as any additional elements. The use of the term "consisting of" and its variations in this description shall encompass only the elements listed thereafter and their equivalents.

[0026] Relative terms such as "approximately," "about," "essentially," etc., used in connection with a quantity or condition, should be understood by persons skilled in the art to include the stated value and to have the meaning given by the context (for example, the term includes at least the degree of error associated with the accuracy of the measurement, the tolerances associated with the stated value [e.g., manufacturing, installation, use, etc.], etc.). Such terminology should also be regarded as a disclosure of the range defined by the absolute values ​​of the two endpoints. For example, the expression "from about 2 to about 4" also indicates the range "from 2 to 4." Relative terminology may refer to plus or minus a percentage (e.g., 1%, 5%, 10%) of a stated value.

[0027] Furthermore, the functionality described here, which is performed by one component, can be performed by multiple components in a distributed manner. Likewise, the functionality performed by multiple components can be consolidated and performed by a single component. Similarly, a component described as performing a particular functionality can also perform additional functionalities not described here. For example, a device or structure that is "set up" in a certain way is at least set up in that way, but may also be set up in ways not listed.

[0028] Fig. 1 and Fig. Figure 2 shows the entirety or sections of a power tool 10 (for example, a miter saw) according to the prior art. The power tool 10 comprises a housing 14, a battery holder 18, an electric motor 22, a printed circuit board assembly (PCBA) 26, and an output unit 30. The electric motor 22 is functionally coupled to the output unit 30 to supply torque to the output unit 30. The PCBA supplies the electric motor 22 with electrical current to electronically commutate the electric motor 22. The battery holder 18 is selectively coupled to a removable battery 34. The battery holder 18 includes a tool terminal block 38 ( Fig. 2) with a variety of tool connections 42 (for example, plug connections, such as flat connectors). The battery 34 ( Fig. 3) comprises a corresponding battery terminal block 46 with a plurality of battery terminals 50 (for example, socket terminals, such as spring clamp terminals) that accommodate the tool terminals 42 when the battery 34 is coupled to the power tool 10.

[0029] Fig. Figure 2 shows the tool connection block 38 of the power tool 10 according to the prior art. The tool connections 42 are connected to power cables 54 (for example, by soldering), which extend from the tool connections 42 to the PCBA 26 (on Fig. 1) extend. The power cables 54 electrically connect the tool terminals 42 to the PCBA 26 and enable the flow of current from the battery 34 to the PCBA 26. The ends of the power cables 54 are usually attached to the PCBA 26 and to the tool terminals 42 via soldered connections.

[0030] Fig. Figures 4-8 show a power tool 100 according to an embodiment of the present disclosure. Like the power tool 10, the power tool 100 comprises a housing 114, a battery holder 118, an electric motor 122, a printed circuit board assembly (PCBA) 126, and an output unit 130. The electric motor 122 is functionally coupled to the output unit 130 to supply torque to the output unit 130. The PCBA 126 supplies the electric motor 122 with electrical current to electronically commutate the electric motor 122. The battery holder 118 is selectively connected to the removable battery 34 ( Fig. 3) coupled. The battery holder 118 includes a tool connection block 138 ( Fig. 5) with a variety of tool connections 142 (for example, plug connections, such as flat plugs). The battery terminals 50 of the battery 34 accept the tool connections 142 when the battery 34 is connected to the power tool 100.

[0031] The power tool 100 does not include power cables connecting the tool terminals 142 to the PCBA 126. Instead, the power tool 100 includes busbars 154 that electrically connect the PCBA 126 to the battery 34. The busbars 154 are made of a conductive metal (for example, copper, zinc, aluminum, alloys thereof, or other metals). Each busbar 154 can consist of a single monolithic part and, unlike the prior art power cables 54, can be relatively rigid, i.e., inflexible.

[0032] With reference to Fig. 4, Fig. 5 to Fig. 6 Each busbar 154 in the illustrated embodiment comprises a first end 158 and a second end 162 opposite the first end. The first end 158 of each busbar 154 defines the tool connections 142. Therefore, the first end 158 does not need to be soldered or otherwise electrically connected to a separate tool connection component, resulting in lower impedance and resistance compared to the prior art. The second end 162 is configured to be electrically connected to the PCBA 126. In the illustrated embodiment, the second end 162 defines an opening 166 (for example, a mounting opening) that accommodates a screw 170 ( Fig. 7A) or another fastening element to establish a direct connection with the PCBA 126. In other embodiments, the opening 166 can be omitted and the busbar 154 can be connected by other means, such as a soldered connection ( Fig. 7B), a clamp connection, a weld connection or the like, electrically attached to the PCBA 126.

[0033] With reference to Fig. Each busbar 154 comprises a plurality of sections or straight segments 172, including a first segment 172a, a second segment 172b, a third segment 172c, and a fourth segment 172d. Each of the straight segments 172 is not aligned parallel to the others and is connected to the others at non-linear sections 176. Since the busbars 154 are rigid, they can be pre-formed (for example, stamped, bent, etc.) to obtain a non-linear shape with multiple non-parallel straight segments 172 so that they can extend unimpeded through the housing 114 of the power tool 100.

[0034] With reference to Fig. 8. The entirety or sections of the busbar 154, or sections thereof, can be coupled to the housing 114 via a form-fit connection. For example, in some embodiments, the busbar 154 can be injection-molded with the housing 114. In such embodiments, the busbar 154 can be substantially embedded in the resin material forming the housing 114, or the busbar 154 can be partially embedded, leaving sections of the busbar 154 substantially exposed. Press-fitting the busbar 154 into the housing 114 can simplify and speed up the installation process of the power tool 100. Furthermore, exposed sections of the busbar 154 can improve heat dissipation from the power tool 100 by remaining exposed during operation to the cooling airflow passing through the power tool 100 (generated, for example, by a fan in the power tool 100).Exposed sections of the busbar 154 can also be selectively coupled to one or more heat sinks (not shown) inside the housing 114 to further improve cooling.

[0035] With reference to Fig.In some embodiments, the power tool 10 comprises busbars 180, such as phase busbars, which electrically connect the PCBA 126 to the electric motor 22. Like the busbars 154, the busbars 180 are also made of a conductive metal (for example, copper, zinc, aluminum, alloys thereof, or other metals). Each busbar 180 can consist of a single monolithic part and be relatively rigid, i.e., inflexible. The busbars 180 can also be coupled to the housing 114 by forming in a similar manner to that described here for the busbars 154. One end of the busbars 180 can be attached to the PCBA 126 by means of a threaded connection or by other devices, such as a soldered connection, a clamping connection, a welded connection, or the like.The other end of each busbar 180 can be secured to the electric motor 22, for example to a stator insulator (not shown), and connected to the respective phases of the motor windings (not shown) to supply the current for each winding phase.

[0036] Although the disclosure has been described in detail with reference to certain preferred embodiments, there are variations and modifications within the scope and concept of one or more independent aspects of the described disclosure. Various features and / or advantages of the disclosure are set forth in the following claims. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] US 63 / 728,374

[0001]

Claims

[1] Power tool designed to be selectively and detachably coupled to a battery, the power tool comprising: a case; an electric motor; a printed circuit board assembly designed to supply the electric motor with electrical current; a drive unit functionally coupled to the electric motor; a tool connection block held by the housing, which includes a tool connection designed to be electrically coupled to the battery; and a busbar that extends between the tool connection and the printed circuit board assembly and connects them electrically; where at least one section of the busbar defines the tool connection. [2] Power tool according to claim 1, wherein the housing comprises a resin material and the busbar is at least partially embedded in the resin material. [3] Power tool according to claim 2, wherein the busbar is injection molded with the housing. [4] Power tool according to claim 1, wherein the busbar is rigid and comprises a plurality of straight segments connected by a plurality of nonlinear sections. [5] Power tool according to claim 4, wherein the plurality of straight segments comprises a first segment, a second segment, a third segment and a fourth segment which are not aligned parallel to each other and are connected to each other at the non-linear sections. [6] Power tool according to claim 1, wherein the busbar comprises a first end and a second end, wherein the tool connection is located at the first end and the second end defines an opening which is configured to receive a screw which fastens the second end to the printed circuit board assembly. [7] Power tool according to claim 1, wherein the busbar is a first busbar and the tool connection is a first tool connection and the power tool further comprises a second tool connection and a second busbar extending between the second tool connection and the printed circuit board assembly and electrically connecting them. [8] Power tool according to claim 1, wherein the busbar comprises a single monolithic conductive element formed from a conductive metal selected from copper, zinc, aluminium or an alloy thereof. [9] Power tool according to claim 8, wherein at least one section of the busbar inside the housing is exposed to an airflow generated by a fan of the power tool in order to dissipate heat. [10] Power tool according to claim 9, wherein the exposed section of the busbar is thermally coupled to a heat sink arranged inside the housing. [11] Power tool according to claim 1, wherein the busbar comprises a first end and a second end, wherein the tool connection is located at the first end and the second end is electrically attached to the printed circuit board assembly by means of a soldered connection. [12] Power tool according to claim 1, wherein the power tool further comprises a plurality of phase busbars which electrically connect the printed circuit board assembly to the respective phase windings of the electric motor. [13] Power tool according to claim 12, wherein one end of each phase busbar is secured to a stator insulator of the electric motor. [14] Power tool according to claim 12, wherein each phase busbar comprises a single monolithic conductive element formed from a conductive metal and coupled to the housing by molding. [15] Power tool according to claim 1, wherein the tool connection is a plug connection designed to be received by a corresponding socket connection of the battery. [16] Busbar for a portable, battery-operated power tool, the busbar comprising: a single monolithic conductive element with: a first end that defines a tool connection which is set up to fit with a battery connection, a second end that is configured to allow electrical attachment to a printed circuit board assembly, and a multitude of straight segments connected by nonlinear sections between the first end and the second end; the busbar is rigid and made of a conductive metal. [17] Busbar according to claim 16, wherein the second end defines a mounting opening which is configured to accommodate a threaded fastening element for coupling the busbar to the printed circuit board assembly. [18] Busbar according to claim 16, wherein the busbar is arranged so that it can be injection molded into a housing of the portable, battery-operated power tool. [19] Method for assembling a portable, battery-operated power tool, the method comprising: Injection molding a busbar into a housing of the portable, battery-operated power tool, wherein the busbar comprises a first end and a second end; and Electrically attaching the second end of the busbar to a printed circuit board assembly of the portable, battery-operated power tool; wherein the first end of the busbar defines a tool connection which is set up to fit a battery connection of a battery. [20] Method according to claim 19, further comprising inserting a screw through an opening in the second end of the busbar and fastening the second end to the printed circuit board assembly by means of the screw, wherein the busbar is rigid and is made of copper, zinc, aluminium or an alloy thereof.

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