Floating Z-axis device

Abstract

The floating Z-axis device comprises an R-axis mechanism and a Z-axis, a shaft cavity corresponding to the Z-axis is formed in the R-axis mechanism, the upper end of the Z-axis is located in the shaft cavity, an adsorption air channel is formed in the Z-axis, an air floating air outlet hole and an adsorption air inlet hole are formed in the inner wall of the shaft cavity, a negative pressure air outlet hole corresponding to the adsorption air inlet hole is formed in the Z-axis, and a positive pressure air channel and a negative pressure air channel are formed in the R-axis mechanism; the other end of the adsorption air channel is used for being connected with an air nozzle; one end of the positive-pressure air passage is connected with an external positive-pressure air source, and the other end is communicated with the air-floating air outlet; one end of the negative-pressure air passage is connected with an external negative-pressure air source, and the other end is communicated with the adsorption air inlet. According to the invention, up-down floating buffering when materials are picked downwards and stressed is realized, meanwhile, the floating small Z shaft is prevented from rotating automatically, and the floating small Z shaft can rotate along with the rotating motor.

Description

Technical Field

[0001] The invention relates to the field of manipulators, and in particular to a floating Z-axis device. Background Art

[0002] Most of the existing Z-axis downward picking-up materials (such as small chips, etc.) devices use a "large Z-axis + R-axis" picking-up structure. The Z-axis is fixed on the guide rail, and the R-axis is fixed on the Z-axis. The Z-axis drives the structure downward to pick up the product through a power source. This method belongs to hard contact material picking up, and there is no floating buffer functional device, which can easily cause damage to the material when picking up the material.

[0003] The existing pickup structure is prone to overshoot and crushing the product, or when the chip is being bonded, the solder paste temperature changes and expands instantly, causing the product to exert an instantaneous upward thrust on the upper structure (such as the nozzle). Because the current pickup structure uses hard connections, although some pickup structures are equipped with pressure sensors for real-time monitoring of force control to adjust the output of the motor force, the chip bonding process is quite fast, and the sensor has not yet had time to transmit the signal to the motor controller. The instantaneous high pressure has disappeared, but the force has already exerted excessive pressure on the product and damaged the product. Summary of the invention

[0004] The technical problem to be solved by the embodiments of the present invention is to provide a floating Z-axis device to achieve up and down floating buffering when picking up materials downwards.

[0005] In order to solve the above technical problems, an embodiment of the present invention proposes a floating Z-axis device, including an R-axis mechanism and a Z-axis. The R-axis mechanism is provided with an axial cavity corresponding to the Z-axis, the upper end of the Z-axis is located in the axial cavity, the Z-axis is provided with an adsorption air duct, the inner wall of the axial cavity is provided with an air flotation outlet hole and an adsorption air inlet hole, the Z-axis is provided with a negative pressure outlet hole corresponding to the adsorption air inlet hole, and the R-axis mechanism is provided with a positive pressure air duct and a negative pressure air duct; one end of the adsorption air duct is connected to the negative pressure outlet hole, and the other end is used to connect the air nozzle; one end of the positive pressure air duct is used to connect to an external positive pressure air source, and the other end is connected to the air flotation outlet hole; one end of the negative pressure air duct is used to connect to an external negative pressure air source, and the other end is connected to the adsorption air inlet hole.

[0006] Furthermore, an air floating block is provided below the R-axis mechanism, an air floating axis plane is provided on the Z-axis, and a plurality of throttle holes are provided on one side of the air floating block corresponding to the air floating axis plane, and the throttle holes are connected to the positive pressure airway.

[0007] Furthermore, there are two groups of air floating blocks, which are symmetrically arranged relative to the Z axis, and two groups of air floating axis planes are correspondingly arranged on the Z axis.

[0008] Furthermore, the outer diameter of the upper end of the Z-axis is greater than the outer diameter of the lower end, the air-floating axis plane is concavely arranged on the lower end, and the up and down movement of the Z-axis is limited by the air-floating block.

[0009] Furthermore, there are a plurality of air flotation outlet holes, and the plurality of air flotation outlet holes are evenly distributed around the inner wall of the shaft cavity.

[0010] Furthermore, the plurality of air flotation outlet holes are divided into a plurality of rows up and down, and the air flotation outlet holes are evenly distributed around the inner wall of the axial cavity.

[0011] Furthermore, a displacement sensor for detecting Z-axis displacement is provided on the R-axis mechanism.

[0012] The beneficial effects of the present invention are as follows: the present invention realizes the up and down floating buffer when the material is picked up downward and subjected to force, and at the same time prevents the floating Z-axis from self-rotating, but can also follow the rotating motor (R-axis motor) to make a rotating motion; the present invention can be directly applied to the R-axis end of the conventional ZR-axis, ensuring that the Z-axis does not rotate arbitrarily while also floating up and down, and does not have friction with the air flotation block, ensuring that only the low friction resistance of the parts and the air film exists at the end, thereby ensuring that during the chip mounting and solid crystal process, when the product is heated and expanded, it can follow the up and down floating, ensuring that the product is not subjected to excessive pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a three-dimensional structural diagram of the floating Z-axis device according to an embodiment of the present invention.

[0014] Figure 2 is a partial exploded view of a floating Z-axis device according to an embodiment of the present invention.

[0015] Figure 3 yes Figure 2 Enlarged view of point F in the middle.

[0016] Figure 4 It is a three-dimensional structural diagram of the air flotation block according to an embodiment of the present invention.

[0017] Figure 5 2 is a bottom view of the floating Z-axis device according to an embodiment of the present invention.

[0018] Figure 6 yes Figure 5 Cross-sectional view at CC.

[0019] Figure 7 It is a bottom view of the floating Z-axis device according to the embodiment of the present invention with the air floating block hidden.

[0020] Figure 8 yes Figure 7 Cross-sectional view at DD in the middle.

[0021] Fig. 9 yes Figure 7 Cross-sectional view at HH in the figure.

[0022] Description of Figure Numbers R-axis mechanism 1, Z-axis 2, adsorption air channel 3, air floatation outlet hole 4, adsorption air inlet hole 5, negative pressure outlet hole 6, positive pressure air channel 7, negative pressure air channel 8, air floatation block 9, throttle hole 10, air floatation axis plane 11, exhaust chamber 12, exhaust hole 13. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present invention is further described in detail below in conjunction with the drawings and specific embodiments.

[0024] In the embodiments of the present invention, if there are directional indications (such as up, down, left, right, front, back, etc.), they are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0025] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0026] Please refer to Figures 1 to 9 The floating Z-axis device of the embodiment of the present invention comprises an R-axis mechanism and a Z-axis. The R-axis mechanism is composed of a rotating R-axis and a shunt seat.

[0027] The R-axis mechanism is provided with an axis cavity corresponding to the Z-axis, and the axis cavity is cylindrical. The upper end of the Z-axis is located in the axis cavity, and an adsorption air channel is provided in the Z-axis. The inner wall of the axis cavity is provided with an air flotation outlet hole and an adsorption air inlet hole. A gap is left between the Z-axis and the axis cavity, and the gas blown out of the air flotation outlet hole diffuses up and down to form an air film. An exhaust cavity can be provided on the inner wall of the axis cavity, and an exhaust hole connected to the exhaust cavity is provided on the R-axis mechanism, and exhaust is exhausted through the exhaust hole. Gas is blown out of the air flotation outlet hole to form an air film between the Z-axis and the inner wall of the axis cavity, thereby reducing the friction force when the Z-axis moves up and down. A negative pressure outlet hole corresponding to the adsorption air inlet hole is provided on the Z-axis, and a positive pressure air channel and a negative pressure air channel are provided in the R-axis mechanism. One end of the adsorption air channel is connected to the negative pressure outlet hole, and the other end is used to connect the air nozzle. A joint is provided at one end of the positive pressure air channel for connecting to an external positive pressure air source, and the other end is connected to the air flotation outlet hole. A joint is provided at one end of the negative pressure air channel for connecting to an external negative pressure air source, and the other end is connected to the adsorption air inlet hole. The external negative pressure air source is connected to the suction nozzle through the negative pressure air channel and the adsorption air channel, and the suction nozzle adsorbs and grabs the material.

[0028] As an implementation method, an air floating block is provided below the R-axis mechanism, an air floating axis plane is provided on the Z-axis, 2n throttle holes are provided on one side of the air floating block corresponding to the air floating axis plane (preferably, there are 2 throttle holes on one air floating block), the throttle holes are connected to the positive pressure airway, and the 2n throttle holes are symmetrically distributed on the left and right sides of the Z-axis, where n is a positive integer. In specific implementation, a number of tiny throttle holes can also be provided on one side of the air floating block corresponding to the air floating axis plane, and the airflow blown out from the several tiny throttle holes forms an entire airflow blowing toward the air floating axis plane, applying pressure to the entire surface of the air floating axis plane (i.e., the airflow pressure applied to both sides of the air floating axis plane along the axis is equal), to prevent the Z-axis from deflecting.

[0029] Preferably, there are two groups of air floating blocks, which are symmetrically arranged relative to the Z axis, and two groups of air floating axis planes are correspondingly arranged on the Z axis. The positive pressure airway between the air floating blocks and the R axis mechanism is sealed by a sealing ring.

[0030] The Z-axis of the present invention can make vertical linear motion and rotational motion in the shaft cavity. The embodiment of the present invention only needs vertical linear motion, so in order to prevent the Z-axis from moving in the rotational direction, air floating blocks are installed on the left and right sides of the bottom of the R-axis mechanism. An air floating film is formed by two small throttle holes on the left and right air floating blocks and the air floating axis plane on the Z-axis, which prevents the Z-axis from rotating and can also make the Z-axis float upward when subjected to axial force.

[0031] As an implementation method, the outer diameter of the upper end of the Z axis is larger than the outer diameter of the lower end, and the air-floating axis plane is concavely arranged on the lower end. The up and down movement of the Z axis is limited by the air-floating block, that is, the distance between the two air-floating blocks matches the distance between the two air-floating axis planes on the Z axis. When the Z axis moves downward, the upper end of the Z axis is limited by the air-floating block; when the Z axis moves upward, the lower end of the Z axis (at the bottom of the air-floating axis plane) is limited by the air-floating block.

[0032] As an embodiment, there are multiple air flotation outlet holes, and the multiple air flotation outlet holes are evenly distributed around the inner wall of the shaft cavity. Preferably, the multiple air flotation outlet holes are divided into multiple rows up and down, and the exhaust flotation outlet holes are evenly distributed around the inner wall of the shaft cavity.

[0033] As an implementation method, a displacement sensor for detecting Z-axis displacement is provided on the R-axis mechanism. After the Z-axis contacts the product, there is an upward displacement fluctuation. By detecting the displacement change, the change signal is transmitted to the controller of the large Z-axis to execute the next step, thereby avoiding the floating Z-axis due to the different thickness of the product, resulting in the suction nozzle not being able to contact the thin product or the low-position product when the large Z-axis moves down to the same height, resulting in abnormal vacuum alarm when sucking the product.

[0034] The present invention can be directly applied to the end of the existing rotating R-axis picking structure. The rotating R-axis is fixed on the large Z-axis and moves up and down with the large Z-axis. The present invention is fixed at the end of the picking structure and moves with the rotating R-axis. Because the present invention adopts an air-floating bearing, the outer circle of the Z-axis of the present invention and the shaft cavity of the R-axis mechanism do not contact each other, but are separated by an air film. In this way, the Z-axis of the present invention is in a floating state. When it is subjected to an upward pressure exceeding the rated value, it will automatically float upward, and will not apply an extrusion force to the material below due to size changes, squeezing the product and causing product damage.

[0035] The present invention adopts a round rod with a round hole structure, so the air-floating shaft can not only float freely up and down, but also rotate 360° at any position when subjected to radial force. Because the Z-axis of the present invention is to follow the rotation of the R-axis motor to adjust the angular position of the picked-up material, if the Z-axis of the present invention is not equipped with a device to prevent rotation, then the rotation accuracy adjustment of the product other than the pick-up buffer cannot be achieved, so it is necessary to provide an anti-rotation structure for the Z-axis of the present invention, and this mechanism cannot affect the free up and down floating of the Z-axis of the present invention, that is, there must be no external force to affect the friction resistance of the free up and down floating of the Z-axis of the present invention, if there is, it will reduce the force control accuracy. Therefore, a non-contact method is required to prevent the Z-axis from rotating. The present invention adopts a principle similar to that of an air-floating bearing, and two planes (i.e., the planes of the air-floating shaft) are provided on both sides of the Z-axis, and then two air-floating blocks are provided on both sides of the two planes, and the small hole throttling on the air-floating block is respectively facing the plane of the small Z-axis, and the air source of the air-floating block is connected to the external positive pressure air source from the positive pressure airway of the R-axis mechanism. The distance between the two air float blocks and the Z-axis air float axis plane is adjusted to a gap of 0.005~0.01mm, and then the high-pressure gas blown out through the small holes of the two air float blocks is throttled to make the two planes of the Z-axis and the two air float blocks have a mutual balancing force to ensure that the Z-axis will not rotate. At the same time, the Z-axis air float axis plane has a preset length up and down (the preset length is consistent with the up and down movement stroke of the Z-axis) to meet the axial up and down floating.

[0036] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A floating Z-axis device, comprising an R-axis mechanism and a Z-axis, characterized in that: An axial cavity corresponding to the Z axis is provided in the R-axis mechanism, the upper end of the Z axis is located in the axial cavity, an adsorption air channel is provided in the Z axis, the inner wall of the axial cavity is provided with an air flotation outlet hole and an adsorption air inlet hole, a negative pressure air outlet hole corresponding to the adsorption air inlet hole is provided on the Z axis, and a positive pressure air channel and a negative pressure air channel are provided in the R-axis mechanism; one end of the adsorption air channel is connected to the negative pressure outlet hole, and the other end is used to connect the air nozzle; one end of the positive pressure air channel is used to connect to an external positive pressure air source, and the other end is connected to the air flotation outlet hole; one end of the negative pressure air channel is used to connect to an external negative pressure air source, and the other end is connected to the adsorption air inlet hole.

2. The floating Z-axis device according to claim 1, characterized in that: An air floating block is provided below the R-axis mechanism, an air floating axis plane is provided on the Z-axis, and a plurality of throttle holes are provided on one side of the air floating block corresponding to the air floating axis plane, and the throttle holes are connected to the positive pressure airway.

3. The floating Z-axis device according to claim 2, characterized in that: There are two groups of air floating blocks, which are symmetrically arranged relative to the Z axis, and two groups of air floating axis planes are correspondingly arranged on the Z axis.

4. The floating Z-axis device according to claim 2, characterized in that: The outer diameter of the upper end of the Z axis is greater than that of the lower end, the plane of the air-floating axis is concavely arranged on the lower end, and the up and down movement of the Z axis is limited by the air-floating block.

5. The floating Z-axis device according to claim 1, characterized in that: There are a plurality of air flotation outlet holes, and the plurality of air flotation outlet holes are evenly distributed around the inner wall of the shaft cavity.

6. The floating Z-axis device according to claim 5, characterized in that: The plurality of air flotation outlet holes are divided into a plurality of rows up and down, and the air flotation outlet holes are evenly distributed around the inner wall of the axial cavity.

7. The floating Z-axis device according to claim 1, characterized in that: The R-axis mechanism is provided with a displacement sensor for detecting Z-axis displacement.

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