JP4140604B2 - Rebar binding machine - Google Patents

Description

  The present invention relates to a reinforcing bar binding machine, and more particularly, to a reinforcing bar binding machine provided with means for suppressing temperature rise in a housing.

  A bundling wire feed mechanism that feeds the bundling wire while bending it in a loop and hangs it around the reinforcing bar, and a bundling wire twisting mechanism that twists and binds the bundling wire wound around the reinforcing bar. 2. Description of the Related Art A motor-driven rebar binding machine that performs a wire twisting operation continuously to perform a one-cycle binding operation is known (for example, Patent Literature 1 and Patent Literature 2). These rebar binding machines have one motor configuration that drives the binding wire feed mechanism and the binding wire twist mechanism with a single motor, and 2 drives the binding wire feed mechanism and the binding wire twist mechanism with different motors, respectively. There is a motor configuration, but in any case, the operation of twisting the binding wire takes a considerable load, and the motor in charge of the twisting operation generates a large amount of heat.

  As a means for dissipating the heat generated by the motor in the electric power tool, a method of cooling the inside of the housing including the motor by wind sent by the fan during rotation of the motor by attaching a fan to the motor shaft (for example, Patent Document 3). However, in rebar binding machines, the motor operation pattern is different from that of electric drills and electric drivers, and even if a fan that rotates with the motor is provided, a sufficient motor cooling effect cannot be obtained. No cooling means is provided.

That is, the operation pattern of the rebar binding machine is a short high-speed operation in which one cycle consisting of the operation of the binding wire feeding mechanism and the binding wire twisting mechanism is 1 second or less, and more specifically the operation of the twisting mechanism. Closes the tip of the torsion mechanism and grips the binding wire, twists to rotate the torsion mechanism, and reverses the motor to release the binding wire and return the torsion mechanism to the initial position. It consists of operation, and the motor switches between forward rotation and reverse rotation in a short time. Therefore, even if a fan is attached to the shaft of the motor, a satisfactory cooling effect cannot be expected because the rotation time of the motor in one cycle is short, the rotation of the fan is reversed in a short time, and the number of rotations is small. Therefore, a protection circuit using a temperature detection element is provided in place of the cooling device, and when the temperature in the housing reaches the set upper limit temperature, the power supply circuit is shut off to prevent the motor, the circuit element, and the housing from burning out. It is configured as follows.
Japanese Utility Model Publication No. 5-003494 JP2003-064876 Japanese Utility Model Publication No. 7-7805

  Since the conventional reinforcing bar binding machine is not provided with any cooling means, the internal temperature gradually rises when the bundling operation is carried out continuously for a long time. Finally, the protection circuit is activated and the power supply is shut off. It becomes unusable until the temperature drops to the safety standard value. At relatively small construction sites, the amount of binding work is small, so the rebar binding machine is rarely disabled due to temperature rise, but at large construction sites such as bridge construction and road construction all day long. The operation becomes unusable due to the temperature rise, and the work must be interrupted, which may cause a delay in the process.

  In order to eliminate such an inconvenience, some cooling means is required. For example, if an electric fan linked to a power switch is simply provided to the reinforcing bar binding machine, the electric fan that rotates constantly consumes a large amount of power. Since it consumes, the inconvenience that the duration of the storage battery of the reinforcing bar binding machine is shortened occurs. Also, in an extremely low temperature environment where the temperature is below 0 ° C, the viscosity of the lubricating oil applied to the rotating mechanism part of the reinforcing bar binding machine decreases, the operating resistance increases, and the capacity of the storage battery also decreases. Therefore, the original performance cannot be demonstrated unless it is warmed up to some extent, but the constant rotation type electric fan blows even in a low temperature environment, so the inside of the rebar binding machine is cooled to below the proper operating temperature and the performance deteriorates The problem of causing

  Therefore, there arises a technical problem to be solved in order to control the temperature of the rebar binding machine within an appropriate range to enable continuous operation for a long time and to suppress power consumption due to cooling as much as possible. Therefore, an object of the present invention is to solve the above problems.

The present invention is proposed to achieve the above object, and the invention according to claim 1 is characterized in that a binding wire feeding mechanism that sends out a binding wire and hangs it around the reinforcing bar, and a binding wire that hangs around the reinforcing bar. a tie wire twisting mechanism for binding the reinforcing bars by rotating gripping the loop, a reinforcing bar binding machine comprising an electric motor to the tool housing for driving at least the tie wire twisting mechanism,
Based on the result of comparison between the cooling fan for cooling the inside of the tool housing, the cooling fan driving means for driving the cooling fan, the internal temperature of the tool housing and the reference temperature Fan drive control means for controlling the cooling fan, and the fan drive control means is provided as a board member having at least a thermal element for detecting the internal temperature, and the board member is provided in the vicinity of the electric motor. in reinforcing bar binding machine which is arranged to,
The board member includes a power circuit board and a control circuit board, and the thermal element provides a reinforcing bar binding machine provided on each of the power circuit board and the control circuit board .

According to a second aspect of the present invention, the power supply circuit board is disposed closer to the electric motor than the control circuit board, and the cooling fan is located on the back side of the electric motor and the electric motor. The reinforcing bar binding machine according to claim 1, which is disposed on or near the axis .

  Since the reinforcing bar binding machine of the present invention cools the inside of the reinforcing bar binding machine with a cooling fan, the temperature rises and is not damaged during continuous work, or the protection circuit is not activated and forcibly stopped, Stability is improved.

  In addition, by disposing a substrate with a thermal element as a temperature detection element to control the on / off of the fan in the vicinity of the electric motor, the internal temperature near the electric motor, which is the largest heat source, can be accurately determined. By detecting, the electric motor can be cooled appropriately.

  In addition, the board member is composed of a power supply circuit board having a relatively large amount of heat generation and a control circuit board having a relatively small amount of heat generation, and a thermal element is disposed on each of the power supply circuit board and the control circuit board. As a result, the temperature control accuracy is improved.

  In addition, the electric motor and the power circuit board with a relatively large amount of heat generation are arranged at a short distance, and the cooling fan is arranged on the back side of the electric motor and on or near the axis of the electric motor, so that the electric motor and the power circuit board are arranged. Both can be efficiently cooled.

  A binding wire feed mechanism that feeds the binding wire and hangs it around the reinforcing bar, a binding wire twist mechanism that binds the reinforcing bar by gripping and rotating the binding wire loop wound around the reinforcing bar, and at least the binding wire twist In a reinforcing bar binding machine provided with an electric motor for driving a mechanism in a tool housing, a cooling fan for cooling the inside of the tool housing, a cooling fan driving means for driving the cooling fan, and an interior of the tool housing Fan drive control means for controlling on / off of the cooling fan based on a result of detecting the temperature and comparing the internal temperature with a reference temperature, and the fan drive control means detects the internal temperature. By providing it as a board member having at least a thermal element and arranging the board member in the vicinity of the electric motor, the temperature of the reinforcing bar binding machine is controlled within an appropriate range for a long time. Enabling operation was achieved the intended purpose of suppressing as much as possible the power consumption by and cooling.

  FIG. 1 shows a reinforcing bar binding machine 1, which includes a binding wire twisting mechanism 3 and a binding wire feeding mechanism 4 in a housing 2, and a magazine 6 disposed in front of the grip portion 5 of the housing 2. A binding wire reel (not shown) is loaded. A storage battery 7 is attached to the end of the grip portion 5, and power is supplied to the torsion motor 9 of the binding wire twist mechanism 3 and the feed motor 10 of the binding wire feed mechanism 4 through the power circuit board (including the control circuit) 8. Supply.

  The binding wire feed mechanism 4 is driven by the feed motor 10 with one V-grooved gear of the two V-grooved gears 11 arranged in the front and back direction of FIG. 1 and meshing with each other. The configuration is such that the binding wire is fed by the gear 11, and the binding wire wound around the binding wire reel is sent upward by the binding wire feed mechanism 4. The sent-out binding wire is shaped into an arc along the inner peripheral guide groove of the upper nose 12 and goes around the reinforcing bar, and the tip goes to the binding wire twisting mechanism 3 along the lower guide plate 13. It is sent.

  The binding wire twisting mechanism 3 is composed of a twisting shaft 14 and three clamp plates 15 (lined up in the direction of the paper surface in the figure) attached to the tip of the twisting shaft 14 and arranged on both sides of the central clamp plate. The two clamp plates thus opened and closed by the cam mechanism. The binding wire is fed through between the central clamp plate and one outer clamp plate, goes around the reinforcing bar and enters between the other outer clamp plate and the central clamp plate, this outer clamp plate closes and the binding wire Clamp the tip of. After clamping the tip of the binding wire, the binding wire feed mechanism 4 is driven in reverse to pull back the binding wire, and the one outer clamp plate described above is closed with the binding wire wrapped around the reinforcing bar, and this clamp plate and Clamp the back end of the binding loop with the central clamp plate.

  Then, the cutter device (not shown) cuts the rear end of the binding wire loop, the torsion shaft 14 rotates with both ends of the binding wire loop clamped, and the ends of the binding wire loop are twisted together. Reinforcing the reinforcing bars. Each operation process of one cycle of binding wire feed, binding wire loop tip clamp, binding wire pullback, binding wire loop rear end clamp, binding wire cut, binding wire twisting and initial position return is performed on the control circuit board 16. The processing is sequentially executed under the control of a mounted microprocessor (not shown).

  In this reinforcing bar binding machine 1, a cooling fan 17 is disposed at the rear end (right in FIG. 1) of the casing 2 as a cooling means inside the casing 2, and the temperature control circuit on the control circuit board 16 It is configured to control the operation. The cooling fan 17 is a unit in which a motor (not shown) and a fan 18 are housed in a fan case 19 as shown in FIG. 3, and the axis of the cooling fan 17 is twisted as shown in FIGS. It is arranged so that it is almost equal to the 9 axis. Therefore, when the fan 18 rotates, air is sucked from the vent hole 20 on the front surface of the torsion motor 9 shown in FIG. 2, and the hole 21a on the rear side surface and the hole 21b on the rear end surface shown in FIG. Then, the hot air is discharged to the outside from the exhaust slit 22 on the rear end face through the cooling fan 17, and the torsion motor 9, which is the largest heat source, can be efficiently cooled. The temperature control circuit controls on / off of the cooling fan 17 by means of a heat sensitive element (thermistor) 23 mounted on the power circuit board 8 and the control circuit board 16 and a comparison control means using a microprocessor or a detection circuit.

  FIG. 4 shows the control routine of the temperature control circuit. When the main switch (not shown) of the reinforcing bar binding machine 1 is turned on and the power is turned on (step 101), the internal temperature information of the reinforcing bar binding machine is compared through the thermal element 23. Sequentially input to the control means. Then, the internal temperature is compared with the reference temperature (a temperature close to the upper limit of the range that does not damage the device, for example, 80 ° C. to 90 ° C.) (step 102). If the internal temperature is lower than the reference temperature, a cooling fan Is maintained in a stopped state (step 103). Then, the cooling fan 17 is started when the internal temperature of the reinforcing bar binding machine exceeds the reference temperature in accordance with the binding work (step 104), and the cooling fan 17 is stopped when the internal temperature falls below the reference temperature (step 104). Step 102 → 103).

  Therefore, the cooling fan 17 does not operate until the internal temperature of the reinforcing bar binding machine 1 exceeds the reference temperature, and the cooling fan 17 blows air only at a high temperature. When the internal temperature falls below the reference temperature, the cooling fan 17 Therefore, useless power consumption can be prevented, and the protection circuit of the reinforcing bar binding machine is not activated, and the reinforcing bar binding machine can be operated continuously for a long time.

  FIG. 5 shows an example of performing finer control than the first embodiment. When the main switch of the reinforcing bar binding machine 1 is turned on and the power is turned on (step 201), the internal temperature information of the reinforcing bar binding machine is input to the sequential comparison control means through the thermal element. When the ON signal is input by operating the trigger switch of the reinforcing bar binding machine (step 202), the internal temperature at that time is compared with the reference temperature (here, 0 ° C. as an example) (step 203), If the temperature is equal to or lower than the reference temperature, the bundling operation is performed without starting the cooling fan 17 (step 204), and the process returns to step 202 after one cycle of bundling operation.

  When the internal temperature exceeds 0 ° C., the cooling fan 17 is activated simultaneously with the execution of the bundling operation (step 205), and counting of a preset fan motor ON duration (for example, 60 seconds) is started (step 206). . If the trigger switch is turned on during the timer count (step 207), the timer count is stopped and cleared (step 208), the process returns to step 203, and the bundling operation (step 204) or the bundling operation and the cooling fan 17 according to the internal temperature. (Step 205).

  If the trigger switch is not operated within 60 seconds from the end of binding, the fan motor is stopped simultaneously with the count-up of 60 seconds (step 210), and the process returns to step 202 to enter the standby state of the trigger switch.

  Therefore, when the inside of the reinforcing bar binding machine 1 is cold in a cold environment, the cooling fan 17 does not operate.When the inside of the reinforcing bar binding machine 1 is above the reference temperature, the cooling fan 17 is driven when the binding mechanism is started. Because the cooling fan 17 is stopped after a certain period of time after the end of binding, the internal temperature rise is suppressed as much as possible, enabling continuous operation of the rebar binding machine for a long time and minimizing power consumption of the cooling fan It can be suppressed to the limit.

  The present invention is not limited to the above-described embodiment, and various modifications are possible within the technical scope of the present invention, and it is natural that the present invention extends to those modifications.

The side view which shows one form of the reinforcing bar binding machine of this invention. FIG. 2 is a view taken along line AA in FIG. FIG. 2 is a view taken along line B-B in FIG. 1. The temperature control flowchart of a reinforcing bar binding machine. The flowchart of the other Example of temperature control.

Explanation of symbols

1 Rebar tying machine
2 Enclosure
3 Binding wire twisting mechanism
4 Bundling wire feed mechanism
7 Storage battery
8 Power circuit board
9 Torsion motor
10 Feed motor
16 Control circuit board
17 Cooling fan
22 Exhaust slit
23 Thermal element

Claims (2)

A binding wire feed mechanism that feeds the binding wire and hangs it around the reinforcing bar, a binding wire twist mechanism that binds the reinforcing bar by gripping and rotating the binding wire loop wound around the reinforcing bar, and at least the binding wire twist an electric motor for driving the mechanism a reinforcing bar binding machine having a tool housing,
Based on the result of comparison between the cooling fan for cooling the inside of the tool housing, the cooling fan driving means for driving the cooling fan, the internal temperature of the tool housing and the reference temperature Fan drive control means for controlling the cooling fan, and the fan drive control means is provided as a board member having at least a thermal element for detecting the internal temperature, and the board member is provided in the vicinity of the electric motor. in reinforcing bar binding machine which is arranged to,
The said board | substrate member consists of a power supply circuit board and a control circuit board, and the said thermal element is provided in each of the said power supply circuit board and a control circuit board, The reinforcing bar binding machine characterized by the above-mentioned. The power circuit board is disposed closer to the electric motor than the control circuit board, and the cooling fan is disposed on the back side of the electric motor and on or near the axis of the electric motor. The reinforcing bar binding machine according to claim 1, wherein:

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