JPH0457614A - Pipe cutter - Google Patents

Abstract

PURPOSE:To enable a gap to be formed between a pipe support roller and a cutting edge with one-touch operation, and allow the easy insertion of a pipe through the gap by fitting a spring pressure releasing lever to a spring mechanism for elastically supporting the cutting edge toward the center of the pipe. CONSTITUTION:The spring pressure of a spring mechanism 4 for elastically supporting a cutting edge 3 toward pipe center is released with the operation of a releasing lever 5. As a result, a pipe can be easily inserted between the cutting edge 3 and pipe support roller.

Description

[Detailed description of the invention]

[Industrial Application Field 1] The present invention mainly relates to a pipe cutter for cutting metal pipes. [Prior Art] A pipe cutter that can cut a pipe at an arbitrary position has a basic structure in which a pipe support roller and a cutting blade located opposite the pipe cut the outer circumference of the pipe while rotating. It's starting to go. The rotary base that holds the pipe support roller and cutting blade has an opening from the outer periphery toward the center that allows the pipe to be cut to be inserted to the center position, and in some cases, the opening is closed at the outer periphery. In order to make the 0-rotation base rotatable, the outer or inner periphery has a gear structure, and if the opening is left open all the way to one outer periphery, there is a ratchet pawl that engages with the gear. Two pieces are provided on the circumference. As an example of the above structure, for example, in Utility Model Publication No. 61-3538, there is a structure in which the annular base that holds the pipe support roller and the cutting blade is divided so that it can be opened when inserting the pipe, and when it is made into an annular shape. The structure is such that the cutting blade is pressed against the pipe by mounting a spring on the connecting bolt. Japanese Patent Publication No. 59-23927 (2) shows a structure in which the annular base is of a split type in the same manner as described above, and on the contrary, internal teeth are provided. In the above two examples, the pipe is cut by manually turning the annular base by operating a handle, but an electric type is also available, for example, in Japanese Patent Publication No. 33963/1983.

[Problems to be Solved by the Invention] There are many points that should be improved in these conventional pipe cutters. For example, when inserting a pipe to be cut between the pipe support roller and the cutting blade, it may be difficult to spread out the cutting blade, which is biased by a spring, or there may be a delay between the insertion of the pipe and the cutting operation. 6. It also has problems such as the time it takes. They are structurally complex and difficult to manufacture, leading to high costs in many cases. The present invention attempts to solve these difficulties by improving the conventional pipe cutter.

[Means to solve the problem]

As a result of considering the various issues mentioned above, we developed a pipe cutter with the structure shown below. That is, in a pipe cutter in which a pipe support roller (2) and a cutting blade (3) are provided at opposite positions sandwiching the pipe in the pipe insertion opening (1), the cutting blade (3) is elastically supported toward the center of the pipe. A pipe cutter, characterized in that a spring pressure release lever (5) is provided to a spring mechanism (4) that releases the spring pressure. ■ A pipe cutter characterized in that the gear that meshes with the ratchet pawl (6) that supports the rotation of the pipe support roller (2) and the cutting blade (3) is an open/close type full-circumference external tooth feeding gear (7); , ■The gear that supports the rotation of the pipe support roller (2) and the cutting blade (3) is an irregularly shaped gear with missing teeth (9), and the feed plate (20) of the gear has a pipe insertion opening (1) and a gear pitch. Rotating pins (8), folded protrusions (26) or large and small teeth (29) (30
) has been developed. In the above structure, the opening/closing type full-circumference external tooth feed gear (7) is a structure in which a part of the annular gear is opened at a hinge portion and feed teeth are provided on the outer periphery. In addition, the irregularly shaped intermittent tooth gear (9) has gear teeth intermittently on the circumference, and a one-rotation pin (8) and a folded protrusion (26).
Either the gear has a structure in which there are about 10 or less relatively large-sized gears that engage with the pipe, or even if it is a regular gear, there are canine teeth (29) in the pipe insertion opening (1) and in other parts. Small teeth (30) are provided, and the canine teeth (29) are structured to protrude from the tooth diameter so as to be fed in contact with both inner surfaces of the opening (1).

[Effect]

In the pipe cutter having the structure shown in (■) above, a spring mechanism (
The spring pressure in step 4) can be released by operating the release lever (5). Therefore, the pipe can be easily inserted. Since the feed gear (7) shown in (2) has an open/close type all-around outer tooth structure, one side of the gear can be opened when inserting the pipe. When cutting, when it is closed to form an annular shape, it has a better balance than one with one end open, and rotates smoothly and eliminates vibration. Furthermore, it is not necessary to provide a plurality of ratchet pawls (6) on the circumference, and rotation is possible by simply providing one ratchet pawl (6). ■Rotating pins (8) and folding protrusions (2G) provided circularly at predetermined intervals on the odd-shaped gear with missing teeth (9) and the feeder (20)
Alternatively, if the large and small teeth (29) and (30) are made rotatable, a complicated mechanism can be simplified. Therefore, it is possible to reduce the number of parts by one part. The feature of this gear is that it can be designed no matter how large the missing tooth part is, so it can be designed with a large diameter, for example 10
It can also be used for cutting PVC pipes of 0 or more sizes.

【Example】

Embodiments of the present invention will be described in detail below with reference to the drawings. 1 to 3 show a first embodiment, in which FIG. 1 is a front view, FIG. 2 is a rear view, and FIG. 3 is a sectional view taken along line AA in FIG. This pipe cutter has a handle (11) provided downward and a ring-shaped rotating base (12) extending inward toward the center of a horseshoe-shaped body (10) with an opening (1a) provided from the center to the outer periphery. is rotatably provided. The rotating base (12) has a pipe support roller (2) and a cutting blade (
3) is maintained. The rotating base (12) is provided with an opening (1b) extending from the outer periphery toward the center, into which a pipe to be cut can be inserted up to the center. A pipe support roller (2) and a cutting blade (3) are provided at opposing positions sandwiching the pipe in the pipe insertion opening (1b).
One pipe support roller (2) has two rollers (2a)
A box-shaped bracket (2b) holding a box is provided so as to be movable toward the center.
3) are always in contact with each other, and can be adjusted according to the pipe diameter using an adjusting screw (13) screwed into the rotary base (12) side. Ratchet claws (6) (6) are provided at two locations on the pipe cutter main body (10) located on the outer periphery of the rotating base (12), and a spring (28) is provided on the back of the ratchet claws (6), so that the ratchet claws (6) are always The outer gear (12) of the rotating base (12)
It meshes with a). The cutting blade (3) is always elastically supported toward the center of the pipe by a spring mechanism (4). That is, the rotating blade (3)
is disk-shaped and rotatably held on the bracket (3a), which is connected to the rotating base (12).
) is provided so that it can freely move forward and backward toward the center. The bracket (3a) has a pressing rod (1
5) is supported by a shaft (16), and the other end of the pressing rod (15) serves as a spring mechanism (4).
7) always urges the cutting blade (3) toward the center. This spring mechanism (4) can be released by a release lever (5). The release lever (5) is an arcuate member that can be rotated on a fulcrum (18) at a distance from the end of the pressing rod (15) opposite to the part in which the biasing spring (17) abuts. be. The arc-shaped handle portion (5a) of the release lever (5) is held by the cutter body (10) by a tension spring (19).
) side so that it always fits within the outer periphery of the circular cutter body. The opposite side of the release lever (5) should protrude a little so that the release part (5) of the spring mechanism (4)
b) Because of this structure, when the handle (5a) of the release lever (5) is pulled as shown by the two-dot chain line in Fig. 1 against the tension spring (19), the release lever ( The release part (5b) of 5) presses the end of the cutting tooth pressing rod (15) against the biasing spring (17). Concomitantly, the press rod (15) rotates based on the fulcrum (14) and retreats the cutting blade (3) attached to its tip via a bracket, thereby preventing the insertion of the pipe. It makes it easier. FIG. 4 shows an example in which the gear that meshes with the ratchet pawl (6) that supports the rotation of the pipe support roller (2) and the cutting blade (3) is an open/close type full-circumference external tooth feeding gear (7). This opening/closing type full-circumference external tooth feed gear (7) has a part of the annular gear that can be opened at a hinge portion (7a), and a feed tooth (7b) is provided on the outer periphery. When inserting the pipe, open a part of the annular gear and insert it. Next, when cutting, if it is closed to form an annular shape, the balance during rotation is better than when one end is open, and one rotation is smooth and there is no perturbation. Furthermore, it is not necessary to provide a plurality of ratchet pawls (6) on the circumference, and even if only one ratchet pawl (6) is provided as shown in the figure, the ratchet pawl (6) always acts on the feed dog (7b) and feeding becomes possible. Figures 5 to 11 show the pipe support roller (2) and cutting blade (3)
An example is shown in which the rotation is performed by a irregularly shaped toothless gear (9). The example shown in Figure 5 differs from the previous examples in which the ratchet pawl (6) meshes with the gear of the rotating base (12), but the pipe support roller (2) and cutting blade (3) are connected to each other. It was attached to a rotating base (12) having an irregularly shaped toothless gear (9). In order to simplify the explanation, unnecessary members are omitted here. A feeder (20) is pivotally supported adjacent to the irregularly shaped toothless gear (9). In this example, as shown in FIG. 6, five pins (8) are installed on the circumference at equal intervals. The irregularly shaped toothless gear (9) is provided with irregularly shaped feed teeth at intervals corresponding to the five pins (8). A part of the irregularly shaped toothless gear (9) is in an open state, and a pipe can be inserted therein. The implanted pin (8
) has a larger pitch.A ratchet (21) is installed adjacent to the feed plate (20), and a handle (22) that can freely rotate independently of the ratchet (21) is attached coaxially to the feed plate (20). A claw (23) is provided. When the handle (22) is reciprocated, the feed plate (20) rotates, and the rotation pin (8) rotates the irregularly shaped toothless gear (9).
Along with this, a pipe support roller (2) and a cutting blade (3) are attached.
) rotates and cuts the pipe. No. 7 @ shows an example in which cutting can be performed not by manual cutting but by motor drive. Feed plate (20) of the above embodiment
A bevel gear (24a) is provided, and this bevel gear (24a)
A bevel gear (
24b) are engaged. The rotation of the odd-shaped gear with missing teeth (9) was made using a pin (8), but in addition to the pin, for example, as shown in Figs. A similar feeding effect can be obtained even if the structure is provided intermittently. FIG. 10 is an example in which the number of teeth of the irregularly shaped gear with missing teeth (9) is increased. In this example, the upper part of the main body (10) is cut out so that a portion of the feed plate (20) is exposed through the cutout. This requires work to match the opening of the main body with the toothless part after cutting the pipe, but a one-way clutch (27) is installed on the back of the bevel gear (24a) so that there is no load in the direction of the arrow. Quickly align teeth. We're doing it safely. In other words, the tooth alignment after cutting the pipe is done using a feed plate (20
) by hand in the direction opposite to the arrow to align the teeth. In this way, by providing about seven teeth and correspondingly about seven pins (8) or protrusions of the feed plate (20), rotation becomes smooth and the effect of quiet rotation can be obtained. Figure 11 shows an irregularly shaped gear with missing teeth (
9) and a feeder (20), the pipe insertion opening (1) is provided with canine teeth (29), the other parts are provided with small teeth (30), and the large teeth (29) are provided with the opening. It has a structure in which it protrudes from the tooth diameter of the feeder (20) so that it is fed in contact with the cylindrical inner surface of the portion (1). By devising the shape of the canine tooth (29), it is possible to eliminate backlash at the missing tooth portion, and smooth rotation can be guaranteed.

【Effect of the invention】

Since the pipe cutter of the present invention has the above-described structure, it is possible to open the space between the pipe support roller and the cutting blade with a single touch, making it easy to insert the pipe. Furthermore, the time required from inserting the pipe to cutting the pipe can be shortened. Adopting an open/close type all-round external tooth structure reduces the number of ratchets,
It prevents vibration during motor drive and can support higher speeds. The irregularly shaped toothless gear is useful for simplifying the mechanism, reducing weight and cost, and it is possible to provide a multifunctional pipe cutter by appropriately combining these improved mechanisms depending on the purpose.

[Brief explanation of the drawing]

1 to 3 show a first embodiment, in which FIG. 1 is a front view, FIG. 2 is a rear view, and FIG. 3 is a sectional view taken along line AA in FIG. FIG. 4 is a front view of the second embodiment. Fifth
, 7 , 8. Figures 10 and 11 are front views showing examples of irregularly shaped toothless gears. Figures 6 and 9 are perspective views of the feeder. (1) Pipe insertion opening (2) Pipe support roller (3
) Cutting blade (4) Spring mechanism (5) Release lever (6) Ratchet pawl (7) Opening/closing type full-circumference external tooth feeding gear (8) Rotating pin (9) Irregular missing tooth gear
(10) Pipe cutter body (14) Fulcrum
(15) Pressing rod (17) Biasing spring (2o) Feeding plate (26) Folding protrusion (29) Canine teeth (30) Small teeth and above Applicant Sodo Matsumoto Super Tool Co., Ltd.

Claims (1)

[Scope of Claims] 1. A pipe cutter in which a pipe support roller (2) and a cutting blade (3) are provided at opposing positions sandwiching the pipe in a pipe insertion opening (1), with the cutting blade (3) being positioned at the center of the pipe. A pipe cutter characterized in that a spring pressure release lever (5) is provided on a spring mechanism (4) elastically supported in the direction. 2. In a pipe cutter in which a pipe support roller (2) and a cutting blade (3) are provided at opposing positions sandwiching the pipe in the pipe insertion opening (1), the rotation of the pipe support roller (2) and the cutting blade (3) A pipe cutter characterized in that the gear that meshes with the ratchet pawl (6) that supports the is an open/close type full-circumference external tooth feeding gear (7). 3. In a pipe cutter in which a pipe support roller (2) and a cutting blade (3) are provided at opposing positions sandwiching the pipe in the pipe insertion opening (1), the rotation of the pipe support roller (2) and the cutting blade (3) The gear that supports the is an irregularly shaped gear with missing teeth (9
), and the feed plate (20) of the gear has a pipe insertion opening (1) and rotating pins (8), folded protrusions (26), or large and small teeth (29) ( 30) A pipe cutter characterized by being provided with.