JPH0637888Y2 - Work clamp device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a work clamp device for clamping a workpiece without pressing it, for example, during honing.

[Conventional technology]

The cylinder wall of the cylinder block of an automobile engine is
Honing is applied to improve the contact with the piston. During this honing process, as shown in FIG. 6, the cylinder block (A) is positioned at the processing position (honing position) using a positioning pin (not shown) that fits into the hole provided on the bottom surface, and then the honing is performed. A cylinder-shaped horn guide (1) having a guide hole (2) matching the cylinder diameter on the outer peripheral surface of the upper opening of the cylinder (B) and being vertically movable by a bracket (3).
Is pressed against the left and right of the hydraulic cylinder (4) to clamp the cylinder block (A) at the processing position and hold the cylinder block (A) in position. Then, after that, a grindstone is inserted into the cylinder (B) from the guide hole (2) of the horn guide (1), and the grindstone is pressed against the cylinder wall (B ') to perform honing processing.

During honing, the horn guide (1) clamps the cylinder block (A) and guides the grindstone.
As a conventional example, there is a honing guide jig disclosed in Japanese Utility Model Laid-Open No. 63-110369.

[Problems to be solved by the device]

As mentioned above, the cylinder block (A) is provided by the horn guide (1) having the guide hole (2) matching the cylinder diameter.
When clamping the horn guide (1), the horn guide (1) is usually supported by a hydraulic cylinder (4) so as to move up and down, and the horn guide (1) is moved to the cylinder block (A) by the pressing force of the hydraulic cylinder (4). I try to press it. However, when the cylinder block (A) is clamped by bringing the horn guide (1) into pressure contact with the cylinder block (A) by the hydraulic cylinder (4), the cylinder block (A) is moved by the horn guide (1). While being clamped, the hydraulic pressure applied to the hydraulic cylinder (4) is constantly applied to the cylinder, so that the cylinder block (A) is distorted by the applied pressure. In this state, the cylinder wall (B ') will be subjected to honing,
There has been a problem that it is very difficult to finish the cylinder wall (B ') into a desired state.

[Means for Solving the Problems]

According to the present invention, a work clamp device is provided with a guide hole for inserting a tool in the center, a lower end surface of which is supported by a horn guide that contacts a workpiece, and a tip end portion of which is swingably supported.
A screw provided on the outer periphery of the central portion of the swing arm engaged with the outer periphery of the horn guide, and an opening provided at the tip of the swing arm is fitted to a spherical portion projecting at the rear end of the swing arm. A part, a guide rod screwed with a screw part provided on the fixing member,
A rotary actuator for vertically moving the horn guide through a swing arm by rotating the guide rod forward and backward and moving the guide rod back and forth.

[Action]

As described above, the guide rod is moved back and forth by the screw fitting between the guide rod and the fixing member, and this movement is converted into the vertical movement by the swing arm, and the horn guide is moved up and down to add the cylinder block. It is clamped by the horn guide without pressing.

〔Example〕

1 to 4 show a horn guide (10) according to the present invention.
Is shown. In the figure, (11) is a pedestal and (1
2) is a pillar standing on the pedestal (11), (13) is a pillar (12)
A support base (14) supported by the main frame is installed on the support base (13). An opening (14a) for rotatably accommodating a rear end of a swing arm (15), which will be described later, is provided at substantially the center of the main frame (14).
And a through hole (14) for guiding a horn guide (16) described later in a vertically movable manner.
b) is provided, and further, in the rear portion of the main frame (14), a through hole (14c) for incorporating a screw mechanism for rotating the swing arm (15) is provided. (15) supports the rear end of the main frame (1) by supporting it through the pin (15a) in the opening (14a) of the main frame (14).
The swing arm (15) is rotatably supported with respect to 4), and the swing arm (15) has a U-shaped bifurcated front portion (15b). The outer circumference of the guide (16) is supported. (16) has a guide hole (16a) in the center that corresponds to the cylinder block diameter.
It is a cylindrical horn guide having. This horn guide (16) has its upper outer peripheral surface inserted through the bush (17) into the through hole (14b) of the main frame (14) so as to be vertically movable, and has a pair of concave portions provided on the lower outer peripheral surface. Groove (16b)
Further, as shown in FIGS. 2 and 3, the roller (18) attached to the tip of the U-shaped front part (15b) of the swing arm (15).
The horn guide (16) is vertically moved while being guided by the through hole (14b) when the swing arm (15) is rotated. (19) is
A guide tube that serves as a fixed member that is inserted and fixed in a through hole (14c) provided in the rear portion of the main frame (14), and (20) is screwed with a screw part (19a) provided in the guide tube (19). Screw part (2
0a) is a guide rod having an outer periphery in the central portion. This guide rod (20) has an opening (20b)
The spherical portion (15c) protruding from the rear end of the swing arm (15) is fitted to connect with the swing arm (15). Then, when the guide rod (20) is rotated by the rotary actuator (21) described later, the screw portion (20a) of the guide rod (20) is screwed with the screw portion (19a) of the guide cylinder (19). Therefore, the guide rod (20) moves back and forth due to the screw fitting between the two.
The swing arm (15) rotates about the pin (15a),
As a result, the horn guide (16) moves up and down. Reference numeral (21) is a rotary actuator attached to the rear end of the main frame (14) for rotating the guide rod (20), and (22) is a rotary actuator (21).
It is a cylindrical drive cam that is fixed to the outer periphery of the shaft (21a) of the rotary actuator (21) in order to transmit the rotational force of the to the guide rod (20). This drive cam (22)
Is rotatably arranged in the through hole (14c) of the main frame (14), and its end face has a guide rod (20).
The driven cam (22) is integrally formed at the rear end of the rear end so as to face the driven cam (22). As shown in FIG. 5, (24) is a circular arc-shaped first projection that is provided on the end surface of the drive cam (22).
Reference numeral (25) is a circular arc-shaped second projection provided on the end surface of the driven cam (23). When the rotary actuator (21) is normally rotated, the end surface (24a) of the first projection (24) is formed. Is the second
Abutting on the end face (25a) of the projection (25) of the
0) is moving forward while rotating forward. When the rotary actuator (21) is rotated in the reverse direction, the end surface (24b) of the first protrusion (24) becomes the end surface (25b) of the second protrusion (25).
The guide rod (20) moves backward while rotating in reverse. (26) is a sensing plate attached to the rear end of the shaft protruding from the rear end of the rotary actuator (21), and (27) and (28) are two proximity switches arranged on the rotation locus of the sensing plate (26). When the sensing plate (26) is positioned immediately before the proximity switches (27) (28), the drive of the rotary actuator (21) is stopped so that the rotation angle of the rotary actuator (21) falls within a predetermined range. It is specified in the.

In the above configuration, in order to clamp the honing-processed cylinder block (A) by the work clamping device (10) according to the present invention, first, the rotary actuator (21) is reversed to guide the guide rod ( 20) is moved backward and the horn guide (16) is raised via the swing arm (15). In this state, the cylinder block (A) is arranged below the horn guide (16), and the cylinder block (A) is fitted by a positioning pin (not shown) fitted into a hole provided on the bottom surface of the cylinder block (A). ) Is positioned with respect to the horn guide (16), and the axis of the cylinder (B) of the cylinder block (A) is aligned with the axis of the horn guide (16). Next, the rotary actuator (21) is normally rotated to move the guide rod (20) forward, and the swing arm (15) is rotated counterclockwise in FIG. 1 about the pin (15a). Lower the horn guide (16) to remove the horn guide (1
The bottom surface of 6) is brought into light contact with the top surface of the cylinder block (A), and in this state, the normal rotation of the rotary actuator (21) is stopped. Then, the guide rod (20) is screw-fitted to the guide tube (19), and the screw portion (20a) of both is engaged.
The position when the rotation of the rotary actuator (21) is stopped is maintained by the self-locking action that occurs between (19a).
Therefore, the horn guide (16) connected to the guide rod (20) via the swing arm (15) also holds the position of the rotary actuator (21) when the rotation is stopped. Therefore, the cylinder block (A) is prevented from moving upward by the horn guide (16) without receiving a strong pressing force from the horn guide (16), and is positioned and held below the horn guide (16). . Thereafter, in this state, a grindstone is inserted into the cylinder (B) through the guide hole (16a) of the horn guide (16), and the cylinder wall (B ') is subjected to honing. When the honing process is completed in this way, the rotary actuator (21) is reversed and
By moving the guide rod (20) backward, the horn guide (16) is raised via the swing arm (15) and the clamp of the cylinder block (A) by the horn guide (16) may be released.

In addition, the rotary actuator (2
Since the guide rod (20) is screw-fitted to the guide tube (19) during normal rotation and reverse rotation by 1), it is necessary to apply a large torque at the start of rotation, but this torque is generated by the drive cam (22). The first protrusion (24) of the driven cam is the second protrusion (2) of the driven cam.
It is not necessary to drive the rotary actuator (21) with a large torque because it is covered by the impact force when it comes into contact with 5).

[Effect of device]

As described above, according to the present invention, the guide rod is moved forward and backward by the screw fitting between the guide rod and the guide cylinder, and this movement is converted into the vertical movement by the swing arm, so that the horn guide is moved up and down. By stopping the forward and backward movement of the guide rod and stopping the vertical movement of the horn guide,
The horn guide retains its position without external pressure. Therefore, if the cylinder block is clamped by the horn guide, it can be clamped without applying a pressing force to the cylinder block, and it is possible to prevent distortion in the cylinder block during clamping. Therefore, it becomes possible to perform honing processing on the cylinder wall of the cylinder block in which no distortion has occurred, and the cylinder wall can be finished in a desired state.

[Brief description of drawings]

1 is a side sectional view of a work clamp device according to the present invention, FIG. 2 is a side view showing an engagement relationship between a horn guide and a swing arm, FIG. 3 is a sectional view taken along line II of FIG. 2, and FIG. Is a rear view of the work clamp device, FIG. 5 is an enlarged sectional view showing a drive cam and a driven cam, and FIG. 6 is a schematic view showing a conventional example of a horn guide. (10) …… Work clamp device, (15) …… Swing arm, (15b) …… Front part of swing arm, (16) …… Horn guide, (16a) …… Guide hole, (19)… … Guide tube, (19a) …… screw part, (20) …… guide rod, (20a) …… screw part, (21) …… rotary actuator.

Claims (1)

[Scope of utility model registration request] 1. A horn guide having a guide hole for inserting a tool in the center thereof, a lower end surface of which is in contact with a workpiece, and a horn guide which is swingably supported through a pin, and a tip portion of which is the outer periphery of the horn guide. The engaging swing arm and the opening provided at the tip are fitted to the spherical portion projecting at the rear end of the swing arm, and
A screw portion provided on the outer periphery of the central portion is screwed with a screw portion provided on the fixing member, and the guide rod is rotated forward and backward, and the guide rod is moved back and forth. A work clamp device comprising a rotary actuator for vertically moving a horn guide.