Power control circuit for powered surgical stapler
An apparatus includes a body, a shaft, a stapling assembly, and a sequential logic device. The body includes a safety switch, a firing actuator, and a motor. The stapling assembly is disposed at a distal end of the shaft, wherein the stapling assembly is configured to selectively move from an open position to a closed position to clamp tissue. The sequential logic device is operatively coupled with the motor and configured to detect an actuation of the safety switch and of the firing actuator. The sequential logic device is further operable to detect an order in which the safety switch and the firing actuator are actuated, compare the detected order to a predetermined order, and in response to determining that the detected order is equivalent to the predetermined order, transmit a motor activation signal to the motor.
1 . An apparatus, comprising:
(a) a handle assembly including:
(i) a body configured to be gripped by a user,
(ii) a motor housed within the body,
(iii) a closure trigger movably coupled to the body, and
(iv) a firing trigger movably coupled to the body, wherein each of the closure trigger and the firing trigger is manually actuatable by a user;
(b) a shaft extending distally from the body;
(c) an end effector operatively coupled with the shaft, wherein the end effector is configured to selectively move from an open position to a closed position to clamp tissue in response to actuation of the closure trigger by the user, wherein the end effector in the closed position is actuatable by the motor to drive a plurality of staples into the clamped tissue; and
(d) a safety switch configured to be mechanically actuated by a portion of the apparatus when the end effector assumes the closed position; and
(e) a sequential logic device operatively coupled with the motor and configured to inhibit activation of the motor unless the safety switch is actuated before the firing trigger, the sequential logic device comprising a plurality of pins including one or more input pins and one or more output pins, each of the one or more input pins configured to receive one of a low input voltage or a high input voltage, each of the one or more output pins configured to transmit one of a low output voltage or a high output voltage,
wherein a select output pin of the plurality of pins is operatively coupled to the motor and is configured to transmit the low output voltage, and
wherein the motor is configured to, when the select output pin transmits the low output voltage, activate and thereby actuate the end effector to drive the plurality of staples into the clamped tissue.
2 . The apparatus of claim 1 , wherein the plurality of pins comprises:
(a) a first input pin configured to receive the high input voltage based on an actuation of the safety switch;
(b) a first set of input pins configured to receive the high input voltage;
(c) a first output pin configured to transmit the high output voltage in response to the first input pin receiving the high input voltage and each of the first set of input pins receiving the high input voltage;
(d) a second input pin configured to receive the high input voltage based on the high output voltage from the first output pin;
(e) a second set of input pins configured to receive the high input voltage;
(f) a third input pin configured to receive the high input voltage based on an actuation of the firing trigger; and
(g) a second output pin configured to transmit the low output voltage in response to the third input pin receiving the high input voltage,
wherein the select output pin is the second output pin.
3 . The apparatus of claim 1 , wherein the sequential logic device includes an analog integrated circuit.
4 . The apparatus of claim 3 , wherein the analog integrated circuit includes one or more latches.
5 . The apparatus of claim 4 , wherein the one or more latches are configured for an edge-triggered mode of operation.
6 . The apparatus of claim 3 , wherein the analog integrated circuit includes a first latch and a second latch, and wherein each pin of the plurality of pins is associated with one of the first latch or the second latch.
7 . The apparatus of claim 6 , wherein an input of the first latch is operatively coupled to the safety switch, and wherein an input of the second latch is operatively coupled to the firing trigger.
8 . The apparatus of claim 3 , wherein the analog integrated circuit includes a first latch and a second latch, wherein an input to the second latch is configured to receive a clocked output signal from the first latch.
9 . The apparatus of claim 1 , wherein the sequential logic device includes a programmable digital processor.
10 . The apparatus of claim 1 , wherein the motor is configured to assume a non- activatable state prior to the select output pin transmitting the low output voltage, and wherein the motor is configured to assume an activatable state subsequent to receiving the low output voltage.
11 . The apparatus of claim 1 , further including a transistor having an input and an output, wherein the safety switch is operatively coupled to the input of the transistor and the sequential logic device is operatively coupled to the output of the transistor.
12 . The apparatus of claim 1 , wherein the end effector includes a stapling assembly and an anvil movable relative to the stapling assembly to transition the end effector from the open position to the closed position, wherein the safety switch is configured to assume an actuated state automatically in response to the anvil advancing toward the stapling assembly to the closed position.
13 . The apparatus of claim 1 , wherein the body includes a chassis having a guidance track configured to receive a protrusion of a safety trigger, wherein the guidance track includes:
(a) a first detent configured to receive the protrusion of the safety trigger in an engaged position,
(b) a second detent configured to receive the protrusion of the safety trigger in a disengaged position,
(c) a channel disposed between the first and second detents that is configured to receive the protrusion when the safety trigger is moved between the engaged and disengaged positions, and
(d) a raised portion protruding from the channel that is configured to force the safety trigger to either the engaged position or the disengaged position.
14 . The apparatus of claim 1 , wherein the safety switch comprises a momentary switch that is configured to be directly contacted and thereby mechanically actuated by a portion of the end effector.
15 . A method for operating a powered surgical stapler comprising an end effector, a motor operably coupled to the end effector, a sequential logic device, a safety switch, and a firing trigger, the sequential logic device comprising a plurality of inputs and one or more outputs, the method comprising sequentially:
(a) receiving, at a first input of the plurality of inputs, a first signal based on an actuation of the safety switch;
(b) receiving, at a second input of the plurality of inputs, a second signal based on an actuation of the firing trigger; and
(c) transmitting, at a select output of the one or more outputs, a third signal in response to:
(i) the first input receiving the first signal, and
(ii) the second input receiving the second signal,
wherein the select output is operatively coupled with the motor, and
wherein the motor is configured to, based on the third signal, activate and thereby actuate the end effector to drive a plurality of staples into clamped tissue.
16 . The method of claim 15 , wherein the sequential logic device comprises one or more latches, the one or more latches comprising the plurality of inputs and the one or more outputs.
17 . The method of claim 16 , wherein the one or more latches are configured for an edge-triggered mode of operation.
18 . The method of claim 16 , wherein:
(a) a first latch of the one or more latches comprises the first input; and
(b) a second latch of the one or more latches comprises the second input.
19 . The method of claim 15 , wherein the end effector includes a stapling assembly and an anvil, the method further comprising advancing the anvil toward the stapling assembly to transition the end effector from an open position to a closed position.
20 . An apparatus, comprising:
(a) a body including a motor and a firing actuator;
(b) a shaft extending distally from the body;
(c) an end effector operatively coupled with the shaft, wherein the end effector is actuatable from an open position to a closed position to clamp tissue, wherein the end effector in the closed position is operable to drive a plurality of staples into the clamped tissue in response to activation of the motor;
(d) a safety switch configured to be directly contacted and thereby mechanically actuated by a portion of the end effector when the end effector transitions from the open position to the closed position; and
(e) a sequential logic device operatively coupled with the motor and comprising an analog integrated circuit having at least one latched switch configured for an edge-triggered mode of operation, the at least one latched switch comprising a plurality of inputs and one or more outputs, wherein the sequential logic device is configured to detect an actuation of the safety switch and an actuation of the firing actuator, wherein the sequential logic device is operable to sequentially:
(i) receive, at a first input of the plurality of inputs, a first signal based on an actuation of the safety switch;
receive, at a second input of the plurality of inputs, a second signal based on an actuation of the firing actuator; and
iii) transmit, at a select output of the one or more outputs, a third signal to the motor in response to:
(A) the first input receiving the first signal, and
(B) the second input receiving the second signal,
wherein the motor is configured to, based on the third signal, activate and thereby actuate the end effector to drive the plurality of staples into the clamped tissue.