A multifunctional sanding machine

Abstract

The present invention relates to a multifunctional sanding machine, belonging to the technical field of electric tools. The multifunctional sanding machine comprises a housing for accommodating a motor, the vertical output shaft of the motor is equipped with an eccentric shaft, the eccentric shaft and the bearing ring on the grinding base plate form a hinged pair, the outer circle of the bearing ring has an insertion hole; the housing is installed with a constraint having a first position and a second position; when the constraint is in the first position, its inner end enters the insertion hole; when the constraint is in the second position, its inner end escapes from the insertion hole. After adopting the present invention, there is no need to replace the base plate, and the conversion between ROS and OS grinding can be conveniently realized by regulating the constraint to meet different usage requirements.

Description

Technical Field

[0001] The invention relates to a sanding machine, in particular to a multifunctional sanding machine, belonging to the technical field of electric tools. Background Art

[0002] A handheld sander is a common electric grinding tool used for sanding the surface of a workpiece. Its basic structure is that a motor with a vertical output shaft is placed at the front end of a shell, and the output shaft is connected to the grinding base plate through an eccentric mechanism. According to the constrained motion state of the grinding base plate, there are two main categories: ROS and OS. The grinding base plate of the former (Random Orbital Sander) is only constrained by the hinge of the eccentric mechanism, and has one more degree of freedom of motion. Therefore, the motion trajectory during grinding is affected by the grinding damping and is random. It takes into account both grinding efficiency and grinding accuracy, and is suitable for rough grinding. Its typical structure can be found in the Chinese patent document with application number 200590000061.2; the grinding base plate of the latter (Orbital Sander) is not only constrained by the eccentric transmission, but also by the flexible part and the rigid part, eliminating the redundant degrees of freedom. Therefore, the grinding trajectory is determined. Although the grinding efficiency is relatively low, the grinding accuracy is high, and it is suitable for fine grinding. Its typical structure can be found in the Chinese patent document with application number 201920108832.3.

[0003] model Grinding amount Surface quality ROS #timg# With spiral corrugation, suitable for coarse grinding OS #timg# No spiral corrugation, suitable for fine grinding

[0004] In the above calculation formula

[0005] D——sand disc diameter, unit: mm;

[0006] P——grit number of sandpaper, unit: pieces / square inch;

[0007] E——Eccentric radius of sanding machine, unit: mm;

[0008] B——effective grinding width of sand grains, unit: mm;

[0009] H——effective grinding height of sand grains, unit: mm;

[0010] W motor ——Motor speed, unit: r / min

[0011] W pad ——Base plate speed, unit: r / min.

[0012] In order to meet the demand for switching between rough grinding and fine grinding, the Chinese patent document with application number 200920179834.8 discloses a tool for moving abrasives, including a tool body; a drive system contained in the tool body and including an output member; a retaining member disposed on the tool body; a first platen having a first attached hub and a first rotatable member; a second platen having a second attached hub and a second rotatable member; and a mode selector disposed on the tool body. By replacing the grinding base plate, the conversion between OS orbital motion and ROS random orbital motion can be achieved with the same motion drive mechanism (see paragraph

[0050] ), without the need to equip two types of sanding machines. However, this technical solution requires the provision of multiple grinding base plates, so it is still not convenient to replace or carry and manage. Summary of the invention

[0013] The purpose of the present invention is to address the shortcomings of the above-mentioned prior art and to propose a multifunctional sanding machine that can switch between ROS and OS with simple adjustment through structural improvement, so that one machine can be used for multiple purposes.

[0014] In order to achieve the above purpose, the basic technical scheme of the multifunctional sanding machine of the present invention is as follows: comprising a housing for accommodating a motor, wherein the vertical output shaft of the motor is provided with an eccentric wheel shaft, wherein the eccentric wheel shaft and the bearing ring on the grinding bottom plate form an articulated pair, and the outer circle of the bearing ring has an insertion hole;

[0015] The housing is provided with a restraining member having a first position and a second position; when the restraining member is in the first position, the inner end thereof enters the insertion hole; when the restraining member is in the second position, the inner end thereof escapes from the insertion hole.

[0016] During the use of the sanding machine of the present invention, when the inner end of the constraint member is out of the insertion hole, the motor drives the grinding base plate through the eccentric mechanism. Since the grinding base plate is only constrained by the hinge of the eccentric mechanism, one more degree of freedom of movement is obtained, so ROS grinding can be achieved; and when the inner end of the constraint member enters the insertion hole, the grinding base plate is constrained by the constraint member in addition to the eccentric transmission, eliminating the extra degree of freedom, so OS grinding can be achieved. It can be seen that after adopting the present invention, there is no need to replace the base plate. The conversion between ROS and OS grinding can be easily achieved through the regulation and operation of the constraint member to meet different usage requirements.

[0017] The present invention is further improved by:

[0018] The shell is installed with a pin as a constraint through a radial hole with a threaded section, and the radial hole has an enlarged diameter hole for limiting the position; the outer section of the pin has an external thread matching the threaded section of the radial hole, and the middle part has an enlarged diameter section corresponding to the enlarged diameter hole.

[0019] The shell is installed with a pin as a restraining member through a radial hole. The radial hole has an enlarged diameter hole for limiting the position, and the outer section has a circumferential groove; the outer section of the pin has a limiting pin matching the circumferential groove, and the middle section has an enlarged diameter section corresponding to the enlarged diameter hole.

[0020] The expanded diameter section abuts against a return spring positioned in the radial hole.

[0021] The diameter of the insertion hole is equal to the sum of the inner end diameter of the pin and twice the eccentricity of the eccentric wheel.

[0022] The insertion hole is waist-shaped, and its length is greater than the sum of the inner end diameter of the pin and twice the eccentricity of the eccentric wheel.

[0023] One end of the insertion hole is embedded in an adjustment block with an adjustment groove.

[0024] The inner diameter of the insertion hole matches the inner diameter of the pin, and the pin has a flexible inner end.

[0025] The vertical output shaft of the motor is equipped with a balancing fan blade with an eccentric wheel shaft at the lower end through a tightening screw. The eccentric wheel shaft is equipped with a bearing ring through a bearing. A grinding base plate is installed below the bearing ring through a fastener, so that the eccentric wheel shaft and the bearing ring on the grinding base plate form a relatively rotatable hinged pair. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described below in conjunction with the accompanying drawings.

[0027] Figure 1 It is a structural schematic diagram of a restraining member in an inserted state in an embodiment of the present invention.

[0028] Figure 2 It is a structural schematic diagram of a restraining member in a disengaged state according to an embodiment of the present invention.

[0029] Figure 3 It is a structural schematic diagram of the second embodiment of the present invention, in the state of the restraining member being inserted.

[0030] Figure 4 It is a structural schematic diagram of the second embodiment of the present invention when the restraining member is in the disengaged state.

[0031] Figure 5 It is a schematic diagram of a partial three-dimensional decomposition structure of the first embodiment of the present invention.

[0032] Figure 6 It is a schematic diagram of the partial three-dimensional decomposition structure of the second embodiment of the present invention.

[0033] Figure 7 It is a partial enlarged structural schematic diagram of the third embodiment of the present invention. DETAILED DESCRIPTION

[0034] Embodiment 1

[0035] The multifunctional sanding machine of this embodiment is as follows Figure 1 and Figure 2 As shown, a motor 2 is placed in the front end of the matching structure housing 1 with a handle 1-1 extending from the rear end. The vertical output shaft 2-1 of the motor 2 is equipped with a balancing fan blade 3 with an eccentric wheel shaft 3-1 at the lower end through a tightening screw 2-2. The eccentric wheel shaft 3-1 is equipped with a bearing ring 4 through a bearing 3-2. A grinding base plate 5 is installed below the bearing ring 4 through a connecting screw 5-1, so that the eccentric wheel shaft 3-1 and the bearing ring 4 on the grinding base plate 5 form a relatively rotatable hinge pair. A sanding layer 5-2 is attached to the lower surface of the grinding base plate 5 as required. The outer circle of the bearing ring 4 has a radial insertion hole 4-1. The housing 1 is equipped with a pin 6 with a first position and a second position as a constraint through a radial hole 1-2 with a threaded section.

[0036] The radial hole 1-2 has an enlarged hole 1-4 that serves as a limit. The outer section of the pin 6 has an external thread 6-3 that matches the threaded section of the radial hole and an outer end knob 6-1. The middle part has an enlarged section 6-2 that corresponds to the enlarged hole 1-4. The enlarged section 6-2 abuts against a return spring 7 positioned in the radial hole 1-2. When the pin 6 is screwed to the first position, its inner end enters the insertion hole 4-1. Since the diameter of the insertion hole 4-1 is equal to the sum of the inner end diameter of the pin and the eccentricity of twice the eccentric wheel, the grinding base plate 5 is constrained by the pin in addition to the eccentric transmission. It has no extra degrees of freedom and can be used for OS grinding after the sander is started. When the pin 6 is screwed to the second position, its inner end slips out of the insertion hole 4-1. At this time, as shown in FIG. Figure 2 As shown, since the grinding base plate 5 is only constrained by the eccentric mechanism hinge, it has one more degree of freedom of movement, so it is used to achieve ROS grinding. As a result, there is no need to replace the base plate. By simply adjusting the pins, the conversion between ROS and OS grinding can be easily achieved to meet different usage requirements.

[0037] In fact, since the insertion hole 4-1 only needs to be constrained in the horizontal direction, it can be Figure 5 As shown in the figure, the waist-shaped hole is made. At this time, as long as its horizontal length is equal to the sum of the inner diameter of the pin and the eccentricity of the two eccentric wheels, it will be sufficient. This not only makes the sanding machine more compact in height, but also the dynamic fit between the height dimension of the waist-shaped hole and the pin diameter is more conducive to maintaining the stability of the bottom plate movement. Of course, the inner diameter of the insertion hole can also match the inner diameter of the pin. In this case, as long as the inner end of the pin is flexible and can adapt to the displacement of the two eccentric distances, it will be sufficient.

[0038] Embodiment 2

[0039] The multifunctional sanding machine of this embodiment is as follows Figure 3 and Figure 4As shown, its basic structure is the same as that of the first embodiment, except that Figure 6 As shown, the outer section of the radial hole 1-2 has a circumferential groove 1-5, and the outer section of the pin 6 has a matching stop pin 6-4, and both are without threads. When switching the grinding mode, the pin 6 is pressed to overcome the force of the return spring 7, and its inner end will abut against the outer circle of the bearing ring 4. When the ring rotates to a certain position, it can be inserted into the insertion hole 4-1, and then the pin is screwed to make the stop pin 6-4 snap into the circumferential groove 1-5 for positioning, without the need to align the inner end of the pin with the insertion hole before screwing it as in the first embodiment.

[0040] Embodiment 3

[0041] The basic structure of the multifunctional sanding machine of this embodiment is the same as that of the second embodiment, except that the length of the insertion hole 4-1 is as follows: Figure 7 As shown, the diameter of the inner end of the pin is larger than the sum of the eccentricity of the two eccentric wheels, and one end of the pin is embedded in the adjustment block 4-2 with the adjustment slot 4-3. Therefore, the length of the insertion hole 4-1 is adjusted by means of the fastener 4-4 so that its action length L is equal to or greater than the sum of the diameter of the inner end of the pin and the eccentricity of the two eccentric wheels. When the pin is inserted and the action length L is adjusted to be equal to the sum of the diameter of the inner end of the pin and the eccentricity of the two eccentric wheels, OS grinding is achieved; when the pin is inserted and the action length L is adjusted to be larger than the sum of the diameter of the inner end of the pin and the eccentricity of the two eccentric wheels, a unique ROS and OS mixed grinding can be achieved. That is, when the pin is in the range of the action length L equal to the sum of the diameter of the inner end of the pin and the eccentricity of the two eccentric wheels, the sander performs OS grinding, and when it exceeds this range, it will perform ROS grinding; and the ROS and OS action ratio in a grinding cycle can be adjusted within a certain range by means of the adjustment block 4-2. Experiments have shown that this unprecedented and unique mixed grinding can produce a grinding effect that cannot be achieved by ROS and OS grinding. It is particularly suitable for efficient grinding of special materials with denser textures, thus making the sander more adaptable.

[0042] In addition to the above embodiments, the present invention may also have other implementation modes. Any technical solution formed by equivalent replacement or equivalent transformation falls within the protection scope required by the present invention.

Claims

1. A multifunctional sanding machine, comprising a housing for accommodating a motor, wherein the vertical output shaft of the motor is provided with an eccentric shaft, wherein the eccentric shaft and the bearing ring on the grinding base plate form an articulated pair, characterized in that: The outer circle of the bearing ring has an insertion hole; The housing is provided with a restraining member having a first position and a second position; when the restraining member is in the first position, its inner end enters the insertion hole; when the restraining member is in the second position, its inner end escapes from the insertion hole; The housing is provided with a pin as a restraining member through a radial hole with a threaded section, the insertion hole is waist-shaped, and its length is greater than the sum of the inner end diameter of the pin and twice the eccentricity of the eccentric wheel; One end of the insertion hole is embedded in an adjustment block having an adjustment groove.

2. The multifunctional sanding machine according to claim 1, characterized in that: The radial hole has an enlarged diameter hole for limiting the position; the outer section of the pin has an external thread matching the threaded section of the radial hole, and the middle part has an enlarged diameter section corresponding to the enlarged diameter hole.

3. The multifunctional sanding machine according to claim 1, characterized in that: The shell is installed with a pin as a restraining member through a radial hole. The radial hole has an enlarged diameter hole for limiting the position, and the outer section has a circumferential groove; the outer section of the pin has a limiting pin matching the circumferential groove, and the middle section has an enlarged diameter section corresponding to the enlarged diameter hole.

4. The multifunctional sanding machine according to claim 2 or 3, characterized in that: The expanded diameter section abuts against a return spring positioned in the radial hole.

5. The multifunctional sanding machine according to claim 2 or 3, characterized in that: The inner diameter of the insertion hole matches the inner diameter of the pin, and the pin has a flexible inner end.

6. The multifunctional sanding machine according to claim 1, 2 or 3, characterized in that: The vertical output shaft of the motor is equipped with a balancing fan blade with an eccentric wheel shaft at the lower end through a tightening screw. The eccentric wheel shaft is equipped with a bearing ring through a bearing. A grinding base plate is installed below the bearing ring through a fastener, so that the eccentric wheel shaft and the bearing ring on the grinding base plate form a relatively rotatable hinged pair.

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